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Background and ObjectivesStudies of hypertensive disorders of pregnancy (HDP), including gestational or chronic hypertension (GH/CH) and preeclampsia/eclampsia (PE/E), suggest associations with early-life and mid-life cognition but have been limited by self-report or use of diagnostic codes, exclusion of nulliparous women, and lack of measurement of cognition in later life. We examined the effects of any HDP, GH/CH, PE/E, and nulliparity on cognition in later life.MethodsParticipants included 2,239 women (median age 73) enrolled in the Mayo Clinic Study of Aging with medical record–abstracted pregnancy information. A cognitive battery of 9 tests was conducted every 15 months. Global cognitive and domain-specific z scores (memory, executive/attention, visuospatial, and language) were outcomes. Linear mixed-effect models evaluated associations between pregnancy history (all normotensive, any HPD, HPD subtype [GH/CH, PE/E], or nulliparous) and cognitive decline, adjusting for age and education. Additional models adjusted for APOE, smoking, hypertension, dyslipidemia, body mass index (BMI), diabetes, stroke, and heart disease. Interactions between pregnancy history and age or education on cognitive performance were examined.ResultsOf the 2,239 women, 1,854 (82.8%) had at least 1 pregnancy (1,607 all normotensive, 100 GH/CH, and 147 PE/E); 385 (17.2%) were nulliparous. Cognitive performance did not cross-sectionally differ for women with a history of any HDP, GH/CH, or PE/E vs women with a history of all normotensive pregnancies; women who were nulliparous had lower global and domain-specific cognition (allp< 0.05) in age- and education-adjusted models. There was an interaction (p= 0.015) between nulliparity and education such that the lower cognitive performance was most pronounced among nulliparous women with ≤12 years of education (beta = −0.42,p< 0.001) vs 12 + years (b = −0.11,p= 0.049). Longitudinally, women with any HDP had greater declines in global cognition and attention/executive z scores compared with women with all normotensive pregnancies. When stratified by HDP type, only women with PE/E had greater declines in global cognition (beta = −0.04,p< 0.001), language (beta = −0.03,p= 0.001), and attention (beta = −0.04,p< 0.001) z scores. Adjustment for vascular risk factors, BMI, smoking, andAPOEdid not attenuate results.DiscussionWomen with a history of HDP, especially PE/E, are at greater risk of cognitive decline in later life.

Background and ObjectivesThe prevalence of midlife cardiovascular conditions and risk factors is higher in men than women. Associations between midlife cardiovascular conditions or risk factors and midlife cognitive decline have been reported, but few studies have assessed sex differences in these associations.MethodsWe included 1,857 participants enrolled in the population-based Mayo Clinic Study of Aging who were 50 to 69 years of age at baseline. Participants were evaluated every 15 months by a coordinator, including neurologic evaluation and neuropsychological testing. The neuropsychological testing used 9 tests to calculate global cognitive and domain-specific (memory, language, executive function, and visuospatial skills) z scores. Nurse abstractors reviewed participant medical records to determine the presence of cardiovascular conditions (coronary heart disease, arrhythmias, congestive heart failure) and risk factors (hypertension, diabetes, dyslipidemia, obesity, ever smoking). Linear mixed-effect models evaluated the association between baseline cardiovascular conditions or risk factors and global and domain-specific cognitive decline. Multivariable models adjusted for demographics, APOE genotype, depression, and other medical conditions. Interactions between sex and each cardiovascular condition or risk factor were examined, and results were stratified by sex.ResultsOverall, 1,465 (78.9%) participants had at least 1 cardiovascular condition or risk factor; the proportion of men was higher than women (767 [83.4%] vs 698 [74.5%], p < 0.0001). Cross-sectionally, coronary heart disease and ever smoking were associated with a lower visuospatial z score in multivariable models. Longitudinally, several cardiovascular conditions and risk factors were associated with declines in global and domain-specific z scores but not visuospatial z scores. Most cardiovascular conditions were more strongly associated with cognition among women: coronary heart disease and other cardiovascular conditions were associated with global cognitive decline only in women (all p < 0.05). In addition, diabetes, dyslipidemia, and coronary heart disease were associated with language z score decline only in women (all p < 0.05). However, congestive heart failure was associated with language z score decline only in men (all p < 0.05).DiscussionMidlife cardiovascular conditions and risk factors are associated with midlife cognitive decline. Moreover, specific cardiovascular conditions and risk factors have stronger associations with cognitive decline in midlife for women than men despite the higher prevalence of those conditions in men.

Introduction: Associations of nonalcoholic fatty liver disease (NAFLD) with dementia are controversial. The full spectrum of NAFLD from simple steatosis to fibrosis has been less investigated. Hypothesis: The severity of NAFLD, especially with the stage of liver fibrosis, is associated with dementia. Methods: The associations between midlife (1990-92, N=9283, mean age 57, female 55%) and late-life (2011-13, N=5138, mean age 75, female 58%) NAFLD and all cause dementia were quantified by Cox regression. NAFLD was characterized using the fatty liver index and liver fibrosis assessment model (FIB-4). Dementia was adjudicated and ascertained through Dec. 31, 2019 from neuropsychological assessments, annual participant or informant contact, and medical record surveillance. We used Cox models with adjustment for demographics, APOE ε4, alcohol, and kidney function. Additional adjustments were made for metabolic factors to explore the independent contribution of NAFLD to dementia. Results: During a median follow-up of 24.5 years after midlife NAFLD assessment, 1854 participants developed dementia. During a median of 6.3 years in late-life, there were 893 dementia cases. A graded increase in dementia risk across the spectrum of NAFLD was observed at midlife (p-trend Figure ). In fact, NAFLD in late-life tended to be protective against dementia. After adjusting for the metabolic factors, the associations remained statistically significant in some categories. Conclusions: Remodeling of hepatic architecture and dysregulation in hepatocellular function in NAFLD at midlife plausibly induce peripheral promoters of neurodegeneration and may expose a large segment of the population to increased risk of dementia. The inverse association of NAFLD with dementia at late-life requires further investigation, possibly reflecting the depletion of susceptibles, the reversibility of NAFLD due to weight loss, and the lack of accuracy in identifying NAFLD using clinical prediction models at older age.

Background and ObjectivesTo determine the contribution of cerebral amyloid angiopathy (CAA) to Pittsburgh compound B (PiB)–PET tracer retention.MethodsParticipants from the Mayo Clinic Study of Aging and Mayo Clinic Alzheimer's Disease Research Center with antemortem PiB-PET imaging for β-amyloid (Aβ) who later underwent autopsy were included in this study. Pathologic regional leptomeningeal, parenchymal, capillary CAA, and Aβ plaque burden were calculated from one hemisphere. Regional lobar amyloid standardized uptake value ratio (SUVR) on PET was calculated from the same hemisphere sampled at autopsy. Single- and multiple-predictor linear regression models were used to evaluate the relative contributions of pathologically determined regional CAA and Aβ plaques to antemortem PiB-PET SUVR.ResultsForty-one participants (30 male, 11 female) with a mean (SD) age at death of 75.7 (10.6) years were included. Twenty-seven (66%) had high PiB signal with a mean (SD) of 2.3 (1.2) years from time of PET scan to death; 24 (59%) had a pathologic diagnosis of Alzheimer disease. On multivariate analysis, CAA was not associated with PiB-PET SUVR, while plaques remained associated with PiB-PET SUVR in all regions (all p < 0.05). In patients without frequent amyloid plaques, CAA was not associated with PiB-PET in any region.DiscussionWe did not find evidence that pathologically confirmed regional CAA burden contributes significantly to proximal antemortem regional PiB-PET signal, suggesting that amyloid PET imaging for measurement of cortical amyloid burden is unconfounded by CAA on a lobar level. Whether CAA burden contributes to PiB-PET signal in patients with severe CAA phenotypes, such as lobar hemorrhage, requires further investigation.

Background and ObjectivesTo evaluate the association between midlife plasma amyloid-β (Aβ1-42, Aβ1-40, Aβ42:Aβ40) and risk of mild cognitive impairment (MCI) and dementia.MethodsPlasma Aβ42 and Aβ40 were retrospectively measured with a fluorometric bead-based immunoassay in a subsample of the Atherosclerosis Risk in Communities cohort study. We investigated the relationship of plasma Aβ42, Aβ40, and Aβ42:Aβ40 ratio measured in midlife and late life and the change from midlife to late life to risk of MCI, dementia, and combined MCI/dementia outcomes in late life (from 2011–2019). We used multinomial logistic regressions estimating relative risk ratios (RRRs) of these cognitive outcomes vs cognitively normal adjusted for age, sex, education, site-race, APOE, hypertension, diabetes, and body mass index.ResultsA total of 2,284 participants were included (midlife mean age 59.2 ± 5.2, 57% female, 22% Black). Each doubling of midlife Aβ42:Aβ40 was associated with 37% lower risk of MCI/dementia (RRR 0.63, 95% confidence interval [CI] 0.46–0.87), but only up to approximately the median (spline model threshold 0.20). Every 1-SD increase in plasma Aβ42 (10 pg/mL) was associated with 13% lower risk of MCI/dementia (RRR 0.87, 95% CI 0.77–0.98), whereas every 1-SD increase in plasma Aβ40 (67 pg/mL) was associated with 15% higher risk of MCI/dementia (RRR 1.15, 95% CI 1.01–1.29). Associations were comparable but slightly weaker statistically when models were repeated using late-life plasma Aβ predictors. Aβ42 and Aβ40 increased from midlife to late life, but changes were not associated with cognitive outcomes.DiscussionMidlife measurement of plasma Aβ may have utility as a blood-based biomarker indicative of risk for future cognitive impairment.

Background and Purpose: Cerebral microbleeds (CMBs) are represented by small areas of hemosiderin deposition, detected on brain magnetic resonance imaging (MRI), and found in ≈23% of the cognitively normal population over age of 60 years. CMBs predict risk of hemorrhagic and ischemic stroke. They correlate with increased cardiovascular mortality. In this article, we sought to determine in a population-based study whether antithrombotic medications correlate with CMBs and, if present, whether the association was direct or mediated by another variable. Methods: The study consisted of 1253 participants from the population-based Mayo Clinic Study of Aging who underwent T2* gradient-recalled echo magnetic resonance imaging. We tested the relationship between antithrombotic medications and CMB presence and location, using multivariable logistic-regression models. Ordinal logistic models tested the relationship between antithrombotics and CMB frequency. Using structural equation models, we assessed the effect of antithrombotic medications on presence/absence of CMBs and count of CMBs in the CMB-positive group, after considering the effects of age, sex, vascular risk factors, amyloid load by positron emission tomography, and apoE. Results: Two hundred ninety-five participants (26.3%) had CMBs. Among 678 participants taking only antiplatelet medications, 185 (27.3%) had CMBs. Among 95 participants taking only an anticoagulant, 43 (45.3%) had CMBs. Among 44 participants taking an anticoagulant and antiplatelet therapy, 21 (48.8%) had CMBs. Anticoagulants correlated with the presence and frequency of CMBs, whereas antiplatelet agents were not. Structural equation models showed that predictors for presence/absence of CMBs included older age at magnetic resonance imaging, male sex, and anticoagulant use. Predictors of CMB count in the CMB-positive group were male sex and amyloid load. Conclusions: Anticoagulant use correlated with presence of CMBs in the general population. Amyloid positron emission tomography correlated with the count of CMBs in the CMB-positive group.

ObjectivesTo determine the prevalence and natural history of sporadic inclusion body myositis (sIBM) and to test the hypothesis that patients with sIBM have higher cancer or mortality rates than the general population.MethodsWe sought patients with sIBM defined by the 2011 European Neuromuscular Centre (ENMC) diagnostic criteria among Olmsted County, Minnesota, residents in 40-year time period.ResultsWe identified 20 patients (10 clinicopathologically defined, 9 clinically defined, and 1 probable) according to the ENMC criteria and 1 patient with all features of clinicopathologically defined sIBM except for symptom onset at p = 0.24). Two-thirds of patients developed dysphagia, and half required a feeding tube. Nine patients required a wheelchair. The median time from symptom onset to wheelchair dependence was 10.5 (range 1–29) years. Overall life expectancy was shorter in the sIBM group compared to the general population (84.1 [95% CI 78–88.4] vs 87.5 [95% CI 85.2–89.5] years, p = 0.03). Thirteen patients died; 9 deaths were sIBM related (7 respiratory and 2 unspecified sIBM complications). Female sex (p = 0.03) and dysphagia (p = 0.05) were independent predictors of death.ConclusionOlmsted County has the highest prevalence of sIBM reported to date. Patients with sIBM have similar risk of cancer, but slightly shorter life expectancy compared to matched patients without sIBM.Classification of EvidenceThis study provides Class II evidence that patients with sIBM have similar risks of cancers and slightly shorter life expectancy compared to controls.

Objective: High plasma ceramide levels and ratios are associated with poor outcomes in individuals with cardiovascular disease; less is known about their relation to cerebral small vessel disease. We examined whether high plasma ceramide levels or ratios were associated with cerebral microbleeds (CMBs) and lacunes and whether associations differ by sex. Approach and Results: We included 548 participants enrolled in the MCSA (Mayo Clinic Study of Aging) with concurrent plasma ceramide assays and magnetic resonance imaging. CMBs were quantified on T2* magnetic resonance imaging and lacunes on T2 fluid-attenuated inversion recovery magnetic resonance imaging. Fasting plasma ceramides were assayed using liquid chromatography-electrospray ionization tandem mass spectrometry. We used logistic regression models adjusting for age, sex, hypertension, and diabetes mellitus to examine the relationship between ceramides and presence of a lacune; hurdle models were used for presence and number of CMBs. Each SD increase in the log ceramide C16:0/24:0 ratio was associated with greater odds of a CMB (odds ratio, 1.28 [95% CI, 1.01–1.64]). There was an interaction between sex and the ceramide C16:0/24:0 ratio ( P =0.049). The association between this ratio and presence of a CMB was stronger for women (odds ratio, 1.87 [95% CI, 1.20–3.00]) than men (odds ratio, 1.09 [95% CI, 0.80–1.46]). Several ceramides and all ceramide ratios were associated with number of CMBs. We did not find associations between plasma ceramides and lacunes. Conclusions: In a population-based sample, the plasma ceramide C16:0/24:0 ratio was associated with CMBs and was stronger for women. Plasma ceramides are differentially associated with cerebral small vessel pathologies.

INTRODUCTION: We examined the association between androgen deprivation therapy (ADT) use and risk of mild cognitive impairment (MCI) among prostate cancer patients. METHODS: We included 241 cognitively unimpaired men, aged 70-90, with a history of prostate cancer prior to enrollment in the population-based Mayo Clinic Study of Aging. Using the Rochester Epidemiology Project medical records-linkage system, ADT use and length of exposure were abstracted. Follow-up visits occurred every 15 months and MCI diagnoses were made based on clinical consensus. Cox proportional hazards models, with age as the time scale, were used to examine the association between ADT use (yes/no) and length of exposure with the risk of MCI adjusting for education, APOE, depression, and the Charlson Index score. RESULTS: There was no association between any ADT use (27.8% of participants) and risk of MCI in the multivariable model [hazard ratio (HR), 1.25; 95% confidence interval (CI), 0.75-2.10]. Although not significant, there was an ADT dose-response relationship for risk of MCI

ObjectiveTo assess whether informant-reported apneas during sleep (witnessed apneas) in cognitively unimpaired (CU) elderly persons are associated with higher levels of brain tau.MethodsFrom the population-based Mayo Clinic Study of Aging, we identified 292 CU elderly ≥65 years of age with both AV-1451 tau-PET and Pittsburgh compound B (PiB)-PET scans and whose bed partners and close relatives had completed a questionnaire that assessed whether participants had witnessed apneas during sleep. For this cross-sectional analysis, we selected the entorhinal and inferior temporal cortices as our regions of interest (ROIs) because they are highly susceptible to tau accumulation. PET signal was scaled to the cerebellum crus to calculate standardized uptake value ratio (SUVR). We fit linear models to assess the association between regional tau and witnessed apneas while controlling for age, sex, years of education, body mass index, hypertension, hyperlipidemia, diabetes, reduced sleep, excessive daytime sleepiness, and global PiB.ResultsForty-three participants (14.7%) were found to have witnessed apneas during sleep. The report of witnessed apneas was associated with higher tau-PET SUVR elevation in our ROIs: 0.049 SUVR (95% confidence interval [CI] 0.010–0.087, p = 0.015) in the entorhinal cortex and 0.037 SUVR (95% CI 0.006–0.067, p = 0.019) in the inferior temporal cortex after controlling for confounders.ConclusionWe identified a significant association between witnessed apneas in CU elderly and elevated tau-PET signal in tau-susceptible brain regions. These results suggest a plausible mechanism that could contribute to cognitive impairment and the development of Alzheimer disease. Longitudinal observations are necessary to determine direction of causality.

ObjectiveTo determine whether quantitative polysomnographic REM sleep without atonia (RSWA) distinguishes between cognitive impairment phenotypes.BackgroundNeurodegenerative cognitive impairment in older adults predominantly correlates with tauopathy or synucleinopathy. Accurate antemortem phenotypic diagnosis has important prognostic and treatment implications; additional clinical tools might distinguish between dementia syndromes.MethodsWe quantitatively analyzed RSWA in 61 older adults who underwent polysomnography including 46 with cognitive impairment (20 probable synucleinopathy), 26 probable non-synucleinopathy (15 probable Alzheimer disease, 11 frontotemporal lobar dementia), and 15 age- and sex-matched controls. Submentalis and anterior tibialis RSWA metrics and automated REM atonia index were calculated. Group statistical comparisons and regression were performed, and receiver operating characteristic curves determined diagnostic RSWA thresholds that best distinguished synucleinopathy phenotype.ResultsSubmentalis—but not anterior tibialis RSWA—was greater in synucleinopathy than nonsynucleinopathy; several RSWA diagnostic thresholds distinguished synucleinopathy with excellent specificity including submentalis tonic, 5.6% (area under the curve [AUC] 0.791); submentalis any, 15.0% (AUC 0.871); submentalis phasic, 10.8% (AUC 0.863); and anterior tibialis phasic, 31.4% (AUC 0.694). In the subset of patients without dream enactment behaviors, submentalis RSWA was also greater in patients with synucleinopathy than in those without synucleinopathy. RSWA was detected more frequently by quantitative than qualitative methods (p = 0.0001).ConclusionElevated submentalis RSWA distinguishes probable synucleinopathy from probable nonsynucleinopathy in cognitively impaired older adults, even in the absence of clinical dream enactment symptoms.Classification of evidenceThis study provides Class III evidence that quantitative RSWA analysis is useful for distinguishing cognitive impairment phenotypes. Further studies with pathologic confirmation of dementia diagnoses are needed to confirm the diagnostic utility of RSWA in dementia.

Introduction The association of prostate cancer and androgen deprivation therapy (ADT) use with the odds of developing mild cognitive impairment (MCI) was determined in men from the population-based Mayo Clinic Study of Aging (MCSA). Methods The study included 2513 men (mean age of 73.1 y) enrolled in the MCSA. A history of prostate cancer, ADT use, and length of ADT exposure before their first MCSA visit was abstracted using the Rochester Epidemiology Project medical records-linkage system. MCI was diagnosed at the baseline visit. Logistic regression was used to determine whether prostate cancer and ADT use was associated with odds of MCI. Results Of the 2513 participants, 349 (13.9%) had a history of prostate cancer; among whom 99 (28.3%) were treated with ADT before MCSA enrollment. There were 382 (15.2%) with a diagnosis of MCI. In the univariate logistic regression models, prostate cancer (odds ratio, 1.50; 95% confidence interval, 1.12-2.00), and ADT exposure (odds ratio, 1.57; 95% confidence interval, 0.96-2.58) were associated with higher odds of MCI. These associations were greatly attenuated and not significant in multivariable models. Conclusions Neither a diagnosis of prostate cancer nor ADT use was associated with odds of MCI in this cross-sectional population-based study.

ObjectiveTo determine the frequency of high-convexity tight sulci (HCTS) in a population-based sample and whether the presence of HCTS and related features influenced participants' cognitive status and classification within the new Alzheimer-biomarker framework.MethodsWe analyzed 684 participants ≥50 years of age who were enrolled in the prospective population-based Mayo Clinic Study of Aging and underwent structural MRI, amyloid PET imaging, and tau PET imaging. A fully automated machine-learning algorithm that had been developed previously in house was used to detect neuroimaging features of HCTS. On the basis of PET and MRI measures, participants were classified as having normal (A−) or abnormal (A+) amyloid, normal (T−) or abnormal (T+) tau, and normal (N−) or abnormal (N+) neurodegeneration. The neuropsychological battery assessed domain-specific and global cognitive scores. Gait speed also was assessed. Analyses were adjusted for age and sex.ResultsOf 684 participants, 45 (6.6%) were classified with HCTS according to the automated algorithm. Patients with HCTS were older than patients without HCTS (mean [SD] 78.0 [8.3] vs 71.9 [10.8] years; p < 0.001). More were cognitively impaired after age and sex adjustment (27% vs 9%; p = 0.005). Amyloid PET status was similar with and without HCTS, but tau PET standard uptake value ratio (SUVR) was lower for those with HCTS after age and sex adjustment (p < 0.001). Despite a lower tau SUVR, patients with HCTS had lower Alzheimer disease (AD) signature cortical thickness. With the amyloid-tau-neurodegeneration framework, HCTS was overrepresented in the T−(N)+ group, regardless of amyloid status.ConclusionThe HCTS pattern represents a definable subgroup of non-AD pathophysiology (i.e., T−[N]+) that is associated with cognitive impairment. HCTS may confound clinical and biomarker interpretation in AD clinical trials.

ObjectiveTo examine whether the use of sex-specific norms and cut scores to identify memory impairment improves diagnostic accuracy of amnestic mild cognitive impairment (aMCI) compared to non–sex-specific (typical) norms/cut scores given the female advantage in verbal memory.MethodsWe calculated sex-specific and typical norms/cut scores (age and education specific) for impairment on the Rey Auditory Verbal Learning Test in the Mayo Clinic Study of Aging. Norms/cut scores were applied to 453 women and 532 men from the Alzheimer's Disease Neuroimaging Initiative. We compared sex differences in rates of aMCI (Jak/Bondi criteria) for sex-specific vs typical norms/cut scores. Using sex-specific cut scores as the true condition and typical cut scores as the predicted condition, we categorized participants as true positives (TPs), false positives (FPs), true negative (TNs), or false negative (FNs). In cross-sectional analyses within sex, we compared positivity rates of CSF hyperphosphorylated tau/β-amyloid (Aβ) and cortical Aβ deposition ([18F]AV45 PET) and APOE ε4 frequency among diagnostic comparison groups.ResultsThe frequency of aMCI was higher in men when using typical norms/cut scores. Using sex-adjusted norms/cut scores led to the identification of 10% FNs (missed aMCI cases) among women and 10% FPs among men. Biomarker analyses supported the hypothesis that sex-specific diagnostic criteria improves diagnostic accuracy. Biomarkers rates were higher in FNs vs TNs and similar in FNs and TPs. Biomarker rates were lower in FPs vs TPs and similar between FPs and TNs.ConclusionResults suggest that non–sex-specific aMCI diagnostic criteria led to a 20% diagnostic error rate. Accounting for sex differences in verbal memory performance may improve aMCI classification.

ObjectiveTo investigate the frequency of levodopa-induced dyskinesia in dementia with Lewy bodies (DLBs) and Parkinson disease with dementia (PDD) and compare these frequencies with patients with incident Parkinson disease (PD) through a population-based cohort study.MethodsWe identified all patients with DLB, PDD, and PD without dementia in a 1991–2010 population-based parkinsonism-incident cohort, in Olmsted County, Minnesota. We abstracted information about levodopa-induced dyskinesia. We compared patients with DLB and PDD with dyskinesia with patients with PD from the same cohort.ResultsLevodopa use and dyskinesia data were available for 141/143 (98.6%) patients with a diagnosis of either DLB or PDD; 87 (61.7%), treated with levodopa. Dyskinesia was documented in 12.6% (8 DLB and 3 PDD) of levodopa-treated patients. Among these patients, median parkinsonism diagnosis age was 74 years (range: 64–80 years); 63.6%, male. The median interval from levodopa initiation to dyskinesia onset was 2 years (range: 3 months–4 years); the median daily levodopa dosage was 600 mg (range: 50–1,600 mg). Dyskinesia severity led to levodopa adjustments in 5 patients, and all improved. Patients with dyskinesia were diagnosed with parkinsonism at a significantly younger age compared with patients without dyskinesia (p < 0.001). Levodopa dosage was unrelated to increased risk of dyskinesias among DLB and PDD. In contrast, 30.1% of levodopa-treated patients with PD developed dyskinesia. In age-, sex-, and levodopa dosage–adjusted models, Patients with DLB and PDD each had lower odds of developing dyskinesia than patients with PD (odds ratio = 0.42, 95% CI 0.21–0.88; p = 0.02).ConclusionsThe dyskinesia risk for levodopa-treated patients with DLB or PDD was substantially less than for levodopa-treated patients with PD.

OBJECTIVES Patients requiring admission to an ICU may subsequently experience cognitive decline. Our objective was to investigate longitudinal cognitive trajectories in older adults hospitalized in ICUs. We hypothesized that individuals hospitalized for critical illness develop greater cognitive decline compared with those who do not require ICU admission. DESIGN A retrospective cohort study using prospectively collected cognitive scores of participants enrolled in the Mayo Clinic Study of Aging and ICU admissions retrospectively ascertained from electronic medical records. A covariate-adjusted linear mixed effects model with random intercepts and slopes assessed the relationship between ICU admissions and the slope of global cognitive z scores and domains scores (memory, attention/executive, visuospatial, and language). SETTING ICU admissions and cognitive scores in the Mayo Clinic Study of Aging from October 1, 2004, to September 11, 2017. PATIENTS Nondemented participants age 50 through 91 at enrollment in the Mayo Clinic Study of Aging with an initial cognitive assessment and at least one follow-up visit. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Of 3,673 participants, 372 had at least one ICU admission with median (25-75th percentile) follow-up after first ICU admission of 2.5 years (1.2-4.4 yr). For global cognitive z score, admission to an ICU was associated with greater decline in scores over time compared with participants not requiring ICU admission (difference in annual slope = -0.028; 95% CI, -0.044 to -0.012; p < 0.001). ICU admission was associated with greater declines in memory (-0.029; 95% CI, -0.047 to -0.011; p = 0.002), attention/executive (-0.020; 95% CI, -0.037 to -0.004; p = 0.016), and visuospatial (-0.013; 95% CI, -0.026 to -0.001; p = 0.041) domains. ICU admissions with delirium were associated with greater declines in memory (interaction p = 0.006) and language (interaction p = 0.002) domains than ICU admissions without delirium. CONCLUSIONS In older adults, ICU admission was associated with greater long-term cognitive decline compared with patients without ICU admission. These findings were more pronounced in those who develop delirium while in the ICU.

ObjectiveTo investigate whether timing, number, and frequency of mentally stimulating activities in midlife and late life are associated with the risk of incident mild cognitive impairment (MCI).MethodsWe conducted a prospective cohort study in the setting of the population-based Mayo Clinic Study of Aging in Olmsted County, Minnesota, including 2,000 individuals aged ≥70 years who were cognitively unimpaired at baseline and were followed for a median of 5.0 years. Participants completed a self-reported survey on timing, number, and frequency of engagement in 5 mentally stimulating activities (reading books, computer use, social activities, playing games, craft activities) at baseline.ResultsThe risk of incident MCI was significantly reduced for participants who engaged in social activities (hazard ratio [95% confidence interval] 0.80 [0.64–0.99]) and playing games (0.80 [0.66–0.98]) in both late life and midlife combined. Using a computer was associated with a decreased risk regardless of timing (not late life but midlife: 0.52 [0.31–0.88]; late life but not midlife: 0.70 [0.56–0.88]; late life and midlife: 0.63 [0.51–0.79]). Craft activities were associated with a reduced risk of incident MCI only when carried out in late life but not midlife (0.58 [0.34–0.97]). Furthermore, engaging in a higher number of activities in late life was associated with a significantly reduced risk of incident MCI (any 2 activities: 0.72 [0.53–0.99], any 3: 0.55 [0.40–0.77], any 4: 0.44 [0.30–0.65], all 5: 0.57 [0.34–0.96]).ConclusionEngaging in a higher number of mentally stimulating activities, particularly in late life, is associated with a decreased risk of MCI among community-dwelling older persons.

ObjectiveTo describe the prevalence of cerebral microbleeds (CMBs) and determine the association between CMBs and β-amyloid burden on PET.MethodsFrom the population-based Mayo Clinic Study of Aging, 1,215 participants (53% male) underwent 3-tesla MRI scans with T2* gradient recalled echo sequences from October 2011 to February 2017. A total of 1,123 participants (92%) underwent 11C-Pittsburgh compound B (PiB)-PET scans. The prevalence of CMBs was derived by adjusting for nonparticipation and standardizing to the Olmsted County, MN, population. The relationship between β-amyloid burden and CMB presence and location was tested using logistic regression models. Ordinal logistic models tested the relationship between CMB frequency and β-amyloid burden.ResultsTwo hundred seventy-four participants (22.6%) had at least one CMB. CMB frequency increased with age by decade (11% aged 60–69 years, 22% 70–79 years, and 39% 80 years and older). After adjusting for age, sex, and hypertension, PiB standardized uptake value ratio (SUVR) was associated with increased odds of a CMB. The association between PiB SUVR and CMBs was location-specific; PiB SUVR was associated with lobar CMBs but not deep CMBs. Age, hypertension, and PiB SUVR were associated with increasing CMB count. CMB density was greatest in parietal and occipital regions; β-amyloid burden correlated with concentration of CMBs in all lobar regions. Among participants with multiple CMBs, greater PiB uptake occurred in the pre- and postcentral gyri superiorly, the superior parietal lobe and precuneus, the angular gyrus, inferior temporal gyrus, and temporal poles.ConclusionsThe prevalence of CMBs increases with age. In this population-based sample, β-amyloid load was associated with lobar but not with deep CMBs.

Background: Prevention strategies for Alzheimer’s disease and Alzheimer’s disease related dementias (AD/ADRDs) are urgently needed for reducing incidence. Intra-patient variability in lipid levels is a potentially modifiable risk factor for incident AD/ADRD. Although regular lipid measurements are a part of common clinical practice and longitudinal data routinely available in electronic health records (EHR), research examining this association between AD/ADRD and lipid variability across multiple lipid types remains scarce. Methods: All residents living in Olmsted County, MN on 1/1/2006 age ≥60 years without an AD/ADRD diagnosis were identified using Centers for Medicare & Medicaid Services diagnostic codes. Persons with ≥3 lipid measurements (total cholesterol or triglycerides) in the 5 years prior to index date were retained. Lipid variability was quantified using variability independent of the mean (VIM). Models were adjusted for traditional risk factors. Associations between lipid variability quintiles and incident AD/ADRD were assessed using Cox proportional hazards regression. Multiple imputation was used for missing covariates. Participants were followed through 2018 for incident AD/ADRD. Results: The final analysis included data on 11,551 participants with total cholesterol and 11,502 participants with triglycerides. Participants had a mean age of 71 (range 60-99) years, and were primarily white (96%). Females (54%) were also slightly more frequent than males. Median follow up was 12.9 years (range: 0-13). Participants in the highest quintile of variability for total cholesterol and triglycerides had a 20% increased risk of incident AD/ADRD. Similar results were found in the subset with complete covariate data. Conclusion: In a large EHR derived cohort, persons in the highest quintile of lipid variation had an increased risk of incident AD/ADRD. Further studies to identify the mechanisms behind this risk factor and replication of these results across a more diverse population are needed.

Background: Atrial fibrillation (AF) is an established risk factor for ischemic stroke, but it can be paroxysmal and may go undiagnosed. An artificial intelligence (AI)-enabled ECG acquired during normal sinus rhythm was recently shown to detect silent AF. The objective of this study was to determine if AI-ECG AF score is associated with presence of cerebral infarcts. Methods: Participants from a population-based study ages 30 to 95 years with T2 fluid attenuation inversion recovery (FLAIR) MRI obtained between October 10, 2011, and November 2, 2017 were considered for inclusion. Participants without ECG were excluded. AI-ECG score was calculated using most recent ECG with normal sinus rhythm at the time of MRI. Presence of infarcts was determined on FLAIR MRI scans. Logistic regression was run to evaluate the relationship between AI-ECG AF score and presence of cerebral infarcts. Similar analyses were performed using history of AF rather than AI-ECG AF score as predictor. Age and sex were included as covariates. We also examined whether a high-threshold AI-ECG score was associated with infarcts. In a prior study, an AI-ECG AF score > 0.5 was associated with a cumulative incidence of AF of 21.5% at 2 years and 52.2% at 10 years. Results: This study included 1,373 individuals. Average age was 69.6 years and 53% of participants were male. There were 136 (10%) individuals with ECG-confirmed AF; 1237 (90%) participants had no AF history. Of participants with AF, 23% (n=31) were on anticoagulation, 47% (n=64) were on antiplatelet and 18% (n=24) were on dual therapy. Only 1.3% (n=16) of patients without AF were on anticoagulation and 47% (n=578) were on antiplatelet therapy. Ischemic infarcts were detected in 214 (15.6%) patients. As a continuous measure AI-ECG was associated with infarcts but not after adjusting for age and sex (p=0.46). AI-ECG AF score > 0.5 was associated with infarcts ( p < 0.001); even after adjusting for age and sex ( p = 0.03). History of AF was also associated with infarcts after adjusting for age and sex ( p = 0.018). Conclusion: AI-ECG AF score and history of AF were associated with presence of cerebral infarcts after adjusting for age and sex. This tool could be useful in select patients with cryptogenic stroke but further investigation would be required.

Introduction: An artificial intelligence (AI) algorithm applied to electrocardiography (ECG) during normal sinus rhythm (NSR) has been shown to predict concomitant atrial fibrillation (AF). We sought to characterize the value of AI-ECG as a predictor of future AF and assess its performance compared to other clinical prediction scores in a population-based sample. Methods: We calculated the AI-ECG probability during NSR in patients who enrolled in the population-based Mayo Clinic Study of Aging with at least one ECG in NSR within two years prior and no history of AF at the time of the baseline study visit. The cumulative incidence of AF was estimated for strata defined by AI-ECG probability and CHARGE-AF score. Cox proportional hazards were fit to assess the independent prognostic value and interaction of AI-ECG probability and CHARGE-AF score. Concordance (c) statistics were calculated for AI-ECG probability, CHARGE-AF score and combined AI-ECG and CHARGE-AF score. Results: A total of 1,936 patients with a median age 75.8 (quartile range [QR] 70.4, 81.8) years, median CHARGE-AF score 14.0 (QR 13.2, 14.7) and median CHADS2VASC score 3 (QR 2, 4) were included in the analysis. The cumulative incidence of AF increased in a stepwise fashion across quartiles of AI-ECG probability and CHARGE-AF score (Figure 1). When compared in the same model, both AI-ECG probability (hazard ratio [HR] 1.76, 95% confidence interval [CI] 1.51-2.04) and CHARGE-AF score (HR 1.90, 95% CI 1.58-2.28) independently predicted AF without significant interaction (p=0.54). C statistics were 0.69 (95% CI 0.66-0.72) for AI-ECG probability, 0.69 (95% CI 0.66-0.71) for CHARGE-AF and 0.72 (95% CI 0.69-0.75) for combined AI-ECG and CHARGE-AF score. Conclusions: In the Mayo Clinic Study of Aging, both the AI-ECG probability and CHARGE-AF score independently predicted time to AF. The AI-ECG may offer a means to assess risk with a single test without requiring manual or automated clinical data abstraction.

ObjectiveTo assess dyskinesia frequency in a population-based cohort of patients with Parkinson disease (PD). Dyskinesia complicates levodopa treatment and affects quality of life.MethodsUtilizing the 1991–2010 population-based, parkinsonism-incident cohort of Olmsted County, MN (n = 669), accessed via the Rochester Epidemiology Project, we identified patients with PD and abstracted levodopa-related dyskinesia information.ResultsOf 309 patients with PD (46.2% with parkinsonisms), 279 (90.3%) received levodopa. Most (230/279; 82.4%) had been treated by a Mayo Clinic neurologist. Median age of the 309 patients with PD at the time of diagnosis was 74.1 years (range 33.1–97.8 years). Median-age levodopa initiation in this cohort was 75 years (range 37–98 years), and median-duration levodopa treatment was 6 years (range 2 months to 19.8 years). Dyskinesia was documented in 84 of 279 patients (30.1%). Median time from levodopa initiation to dyskinesia onset was 4 years (range 2 months to 20 years); those with dyskinesia (65.5%; 55/84) developed it within 5 years of levodopa initiation (9 within the first year). Dyskinesia was mild in 57/84 (67.9%), moderate in 16/84 (19.1%), and severe in 9/84 (10.7%); severity was not reported in 2 cases. Dyskinesia severity led to levodopa adjustments or amantadine initiation in 60.7% (51/84 of those with dyskinesia), with improvement in 23/51 (45.1%). Thirteen patients with dyskinesia underwent deep brain stimulation, reporting marked improvement. Postmortem examination confirmed Lewy body disease in 7 autopsied cases.ConclusionsLevodopa-induced dyskinesia affected 30% of the patients with PD in our cohort. Mayo neurologists favoring levodopa dosage optimization treated most patients. Dyskinesia was severe in 3.2% of all levodopa-treated patients with PD (10.7% of all patients with dyskinesia) with marked improvement among those treated with deep brain stimulation.

Objective Women with a history of preeclampsia are at an increased risk of hypertension and structural brain changes. However, the combined effect of both preeclampsia and late-life hypertension on brain structural changes is not known and was investigated in this study. Methods Participants were identified from the population-based Rochester Epidemiology Project cohort. Four groups of women were recruited and investigated in this study: first, women with a history of normotensive pregnancy who have late-life hypertension (n = 8, median age = 62), second, women with a history of normotensive pregnancy who do not have late-life hypertension (n = 32, median age = 59), third, women with a history of preeclampsia who have late-life hypertension (n = 24, median age = 60), and fourth, women with a history of preeclampsia who do not have late-life hypertension (n = 16, median age = 57). Cerebrovascular disease lesions on MRI, and total gray matter volumes were assessed. Results Total gray matter volumes were smaller in women with a history of preeclampsia and late-life hypertension compared with the other groups. Voxel-based morphometry demonstrated that the volume changes were localized to the posterior brain regions, particularly the occipital lobe gray matter in women with a history of preeclampsia and late-life hypertension. Conclusion Having late-life hypertension superimposed on a history of preeclampsia affects the brain structure differently than having either a history of preeclampsia alone or a history of normotensive pregnancy either with or without late-life hypertension.

Objective:To estimate the prevalence of elevated brain amyloid and reduced cortical thickness (as a marker for neurodegeneration) in a defined population.Methods:Mayo Clinic Study of Aging participants underwent MRI to assess a composite Alzheimer disease (AD) signature cortical thickness measure and PET to assess brain amyloid accumulation. Participants were characterized as having elevated amyloid (A+/A−), reduced cortical thickness (N+/N−), and A+N+, A+N−, A−N+, or A−N−. The prevalence of AD biomarkers was derived by adjusting for nonparticipation and standardizing to the Olmsted County, Minnesota, population.Results:Among 1,646 participants without dementia (mean age 70.8 years; 53.2% men), the prevalence (95% confidence interval) of amyloidosis was 21.1% (19.1%–23.2%): women, 24.3%; men, 17.5%. The prevalence of reduced cortical thickness was 28.9% (26.4%–31.5%): women, 27.9%; men, 30.2%. The prevalence estimates of biomarker categories were as follows: A−N−: 61.4%; A+N−: 9.7%; A−N+: 17.4%; and A+N+: 11.5%, and varied by sex and by APOE ε4 carrier status. In men, prevalence estimates were as follows: A−N−: 62.6%; A+N−: 7.3%; A−N+: 19.9%; and A+N+: 10.2%. In women, prevalence estimates were as follows: A−N−: 60.4%; A+N−: 11.7%; A−N+: 15.3%; and A+N+: 12.6%. In ε4 carriers, prevalence estimates were as follows: A−N−: 54.6%; A+N−: 16.6%; A−N+: 12.4%; and A+N+: 16.4%. In non-ε4 carriers, prevalence estimates were as follows: A−N−: 63.3%; A+N−: 6.9%; A−N+: 19.9%; and A+N+: 10.0%.Conclusions:These prevalence estimates are important for understanding age-related trends in amyloid positivity and AD signature cortical thickness in the population, and for potentially projecting the future burden of biomarkers in elderly persons.

Objective:To assess whether noninvasive proton magnetic resonance spectroscopy (1H-MRS) tissue metabolite measurements at baseline can predict an increase in the rate of β-amyloid (Aβ) accumulation on serial PET in clinically normal (CN) older adults.Methods:Consecutive participants aged 60 years and older (n = 594) from the Mayo Clinic Study of Aging who were CN at baseline and who underwent 1H-MRS from the posterior cingulate voxel and longitudinal 11C-Pittsburgh compound B (PiB)–PET were included. The rate of Aβ accumulation by serial cortical PiB standardized uptake value ratios was estimated as a function of baseline 1H-MRS metabolite ratios and time using mixed-effect models adjusted for age, sex, and APOE ε4. Effect of APOE ε4 on the relationship between baseline MRS and an increased rate of Aβ accumulation was also assessed.Results:Among all participants, a higher myo-inositol (mI)/creatine (p = 0.011) and a lower N-acetylaspartate/mI (p = 0.006) at baseline were associated with an increased Aβ accumulation over time after adjusting for age, sex, and APOE ε4. APOE ε4 did not modify the association of baseline 1H-MRS metabolite ratios and rate of Aβ accumulation. However, APOE ε4 carriers accumulated Aβ faster than noncarriers regardless of the baseline Aβ load (p = 0.001).Conclusion:Among CN older adults, early metabolic alterations on 1H-MRS and APOE ε4 status are independently associated with an increased rate of Aβ accumulation. Our findings could have important implications for early diagnosis and identification of individuals for secondary prevention trials, because an increased rate of Aβ accumulation in CN older adults may confer a higher risk for cognitive decline and mild cognitive impairment.

BACKGROUND The prevalence of HIV-associated neurocognitive disorders (HAND) has not changed considerably in the last two decades. Potent antiretroviral therapy has shifted the severity of HAND to milder phenotypes, but excess morbidity and mortality continue to be associated with HAND. Changes in numerous markers of immune function, inflammation, and cellular stress have been repeatedly associated with HAND, but the underlying systems that drive these changes have not been identified. METHOD In this study, we used systems informatics to interrogate the cerebrospinal fluid proteomic content of longitudinal samples obtained from HIV-infected adults with stably unimpaired, stably impaired, worsening, or improving neurocognitive performance. RESULTS AND CONCLUSION The patterns of change in cerebrospinal fluid protein content implicated the induction of acute phase and complement systems as important regulators of neurocognitive status. Worsening neurocognitive performance was preceded by induction of acute phase and complement systems, whereas improving neurocognitive performance was preceded by a downregulation of these systems.

Background: Although white matter hyperintensities (WMH) have been viewed as a marker of vascular disease, pathology studies have found an association of WMH with Alzheimer’s disease (AD) pathologies. Our objective was to investigate the topographic patterns of WMH associated with AD biomarkers. Methods: From the population-based Mayo Clinic Study of aging, 434 non-demented participants with FLAIR-MRI, tau-PET and PiB-PET scans were identified. A subset had microbleeds on T2* GRE scans. We ran SPM12 based voxel-wise multiple regression analyses to detect WMH regions associated with AD biomarkers (global amyloid from PiB-PET and meta-ROI tau uptake from tau-PET) adjusting for age, sex, and hypertension. For amyloid associations, we additionally adjusted for tau and vice versa. Results: Topographic patterns of WMH associated with amyloid after both voxel and cluster level corrections primarily included periventricular WMH (frontal and parietal lobes). Masks with lenient threshold (greater detection sensitivity) and strict thresholds (greater detection specificity) are shown in the figure. (A) and (B) show the areas of positive associations between PIB ratio and WMHs adjusted by age, sex, education, hypertension and Tau meta ROI. The sensitive mask (A) was thresholded at FDR p Conclusion: Amyloid but not tau load on PET was associated with WMH topographically. The WMH regions associated with amyloid were associated with CMBs suggesting that cerebral amyloid angiopathy may be contributing to the relationship between amyloid and WMH.

Background: Non-traumatic convexal subarachnoid hemorrhages (cSAH) in the elderly can be a manifestation of cerebral amyloid angiopathy (CAA) and predict future intracerebral hemorrhage risk. The frequency of cSAH in the elderly population is unknown. Our objective was to determine the frequency of convexal subarachnoid hemorrhage in a population-based study among individuals who underwent amyloid PET imaging. Methods: Between 11/29/2004 and 3/11/2017 there were 1,687 participants ages 50-years and older in the population-based Mayo Clinic Study of Aging (MCSA) with Pittsburgh compound B (PiB) PET imaging. All intracerebral hemorrhages among participants were identified utilizing the Rochester Epidemiology Project’s records linkage system, and records and images were reviewed to identify those with both symptomatic and asymptomatic convexal subarachnoid hemorrhage. Neuroimaging characteristics, demographics, medications, and ApoE genotype were recorded. Results: Four (0.23%) cSAHs were identified among the individuals who underwent PiB PET imaging. Three were women and median age was 73 (range: 67-84). cSAH occurred in the following locations: right frontal (3), and right parieto-occipital (1). Two went on to develop a lobar intracerebral hemorrhage at a median of 4.75 years after cSAH. Coexisting cerebral microbleeds were identified in one case. The APOE allele combinations of the four participants were: 3/3, 3/3, 2/2, and 2/3. On PiB PET imaging, the median SUVR was 1.81 (range: 1.38-2.34). Conclusion: cSAH is a relatively rare manifestation of CAA occurring in less than 1% of the general population, but may represent a subset with a high risk of future intracerebral hemorrhage. Half of the participants with cSAH had an APOE e2 allele.

Objective: To determine risk and protective factors for mild cognitive impairment (MCI) among persons 85 years and older. Methods: Participants in the population-based prospective Mayo Clinic Study of Aging were comprehensively evaluated at baseline and at 15 monthly intervals to determine incident MCI. At baseline, lifestyle factors in midlife and late life were assessed by self-reported questionnaire; vascular and comorbid conditions were abstracted from participants9 medical records. Results: Of 256 participants who were cognitively normal at enrollment (median age 87.3 years, 62% women), 121 developed MCI at a median 4.1 years of follow-up. Predictors of MCI were APOE e4 allele (hazard ratio [HR] 1.89; p = 0.008), current depressive symptoms (HR 1.78; p = 0.02), midlife onset of hypertension (HR 2.43; p = 0.005), increasing number of vascular diseases (HR 1.13; p = 0.02), and chronic conditions from the Charlson Comorbidity Index (HR 1.08; p = 0.006). Models were adjusted for sex and education, with age as the time variable. The risk of MCI was reduced for participants who reported engagement in artistic (HR 0.27; p = 0.03), craft (HR 0.55; p = 0.02), and social (HR 0.45; p = 0.005) activities in both midlife and late life, and in the use of a computer in late life (HR 0.47; p = 0.008). Conclusions: Chronic disease burden increases risk of MCI, whereas certain lifestyle factors reduce risk in persons 85 years and older. This implies that preventive strategies for MCI may need to begin in midlife and should persist throughout late life.

Objectives To identify prognostic surrogate markers for change in cognitive states of HIV-infected patients. Design Longitudinal cerebrospinal fluid (CSF) samples were collected from 98 HIV-infected patients identified by temporal change in cognitive states classified as normal, stably impaired, improving and worsening. Methods The metabolic composition of CSF was analysed using H nuclear magnetic resonance (H NMR) spectroscopy that focused on energy metabolites. Metabolic biomarkers for cognitive states were identified using multivariate partial least squares regression modelling of the acquired spectra, combined with nonparametric analyses of metabolites with clinical features. Results Multivariate modelling and cross-validated recursive partitioning identified several energy metabolites that, when combined with clinical variables, classified patients based on change in neurocognitive states. Prognostic identification for worsening was achieved with four features that included no change in a detectable plasma viral load, elevated citrate and acetate; decreased creatine, to produce a model with a predictive accuracy of 92%, sensitivity of 88% and 96% specificity. Prognosis for improvement contained seven features that included first visit age less than 47 years, new or continued use of antiretrovirals, elevated glutamine and glucose; decreased myo-inositol, β-glucose and creatinine to generate a model with a predictive accuracy of 92%, sensitivity of 100% and specificity of 84%. Conclusion These CSF metabolic results suggest that worsening cognitive status in HIV-infected patients is associated with increased aerobic glycolysis, and improvements in cognitive status are associated with a shift to anaerobic glycolysis. Dietary, lifestyle and pharmacologic interventions that promote anaerobic glycolysis could protect the brain in setting of HIV infection with combined antiretroviral therapy.

Introduction: Cortical superficial siderosis (cSS) refers to deposition of blood breakdown products along the cerebral cortex, causing characteristic staining patterns seen with iron-sensitive MRI techniques. Cortical superficial siderosis is a relatively rare disorder, but has been linked to cerebral amyloid angiopathy and Alzheimer’s disease. The objective of this study was to determine the frequency and natural history of cSS in the general elderly population. Methods: MRI scans from the Mayo Clinic Study of Aging (MCSA), an ongoing population-based study of elderly residents in Olmsted County, Minnesota, were reviewed by neuroradiologists. Participants with cSS were identified based on linear pattern of hypointensity on gradient recalled echo imaging consistent with cSS. Exclusion criteria were: 1) MRI findings not consistent with cSS or 2) alternative explanation for MRI findings (such as aneurysmal subarachnoid hemorrhage, intracranial surgery, or trauma). Additional data abstracted included extent of cSS, presence of cerebral microbleeds, and clinical outcome. Results: Eleven out of 1,441 participants had MRI scans showing cSS (0.8%). When stratified by age, the frequency was 0.4% in those 50 to 70 years old and 1.1% in those over 70 years old. Six participants had only focal involvement of cSS (restricted to three or fewer sulci) and five had disseminated involvement (affecting more than three sulci). Microbleeds were seen in four of five (80%) participants with disseminated cSS, but none with focal cSS. Five participants (2 focal, 3 disseminated cSS) had follow up MRI scans, with an average follow up of 25 months. There was no further hemorrhage in those with focal cSS. However, all three participants with disseminated cSS experienced additional hemorrhage: one with new microbleeds, one with new microbleeds and lobar hemorrhage, and one with sulcal subarachnoid hemorrhage and lobar hemorrhage. Conclusion: Although rare, cSS may be encountered in the general elderly population. Extent of involvement of cSS and concomitant microbleeds may be important risk factors for progression of disease and intracerebral hemorrhage. The clinical significance of focal cSS occurring in the absence of microbleeds requires further investigation.

Objective: To test the hypotheses predicted in a hypothetical model of Alzheimer disease (AD) biomarkers that rates of β-amyloid (Aβ) accumulation on PET imaging are not related to hippocampal neurodegeneration whereas rates of neurodegenerative brain atrophy depend on the presence of both amyloid and neurodegeneration in a population-based sample. Methods: A total of 252 cognitively normal (CN) participants from the Mayo Clinic Study of Aging had 2 or more serial visits with both amyloid PET and MRI. Subjects were classified into 4 groups based on baseline positive/negative amyloid PET (A+ or A−) and baseline hippocampal volume (N+ or N−). We compared rates of amyloid accumulation and rates of brain atrophy among the 4 groups. Results: At baseline, 148 (59%) were amyloid negative and neurodegeneration negative (A−N−), 29 (12%) amyloid negative and neurodegeneration positive (A−N+), 56 (22%) amyloid positive and neurodegeneration negative (A+N−), and 19 (8%) amyloid positive and neurodegeneration positive (A+N+). High rates of Aβ accumulation were found in those with abnormal amyloid at baseline and were not influenced by hippocampal neurodegeneration at baseline. In contrast, rates of brain atrophy were greatest in A+N+. Conclusions: We describe a 2-feature biomarker approach to classifying elderly CN subjects that is complementary to the National Institute on Aging–Alzheimer9s Association preclinical staging criteria. Our results support 2 key concepts in a model of the temporal evolution of AD biomarkers. First, the rate of Aβ accumulation is not influenced by neurodegeneration and thus may be a biologically independent process. Second, Aβ pathophysiology increases or catalyzes neurodegeneration.

Objectives: We determined whether head trauma was associated with amyloid deposition and neurodegeneration among individuals who were cognitively normal (CN) or had mild cognitive impairment (MCI). Methods: Participants included 448 CN individuals and 141 individuals with MCI from the Mayo Clinic Study of Aging who underwent Pittsburgh compound B (PiB)-PET, fluorodeoxyglucose-PET, and MRI. Head trauma was defined as a self-reported brain injury with at least momentary loss of consciousness or memory. Regression models examined whether head trauma was associated with each neuroimaging variable (assessed as continuous and dichotomous measures) in both CN and MCI participants, controlling for age and sex. Results: Among 448 CN individuals, 74 (17%) self-reported a head trauma. There was no difference in any neuroimaging measure between CN subjects with and without head trauma. Of 141 participants with MCI, 25 (18%) self-reported a head trauma. MCI participants with a head trauma had higher amyloid levels (by an average 0.36 standardized uptake value ratio units, p = 0.002). Conclusions: Among individuals with MCI, but not CN individuals, self-reported head trauma with at least momentary loss of consciousness or memory was associated with greater amyloid deposition, suggesting that head trauma may be associated with Alzheimer disease–related neuropathology. Differences between CN individuals and individuals with MCI raise questions about the relevance of head injury–PET abnormality findings in those with MCI.

To estimate rates of progression from mild cognitive impairment (MCI) to dementia and of reversion from MCI to being cognitively normal (CN) in a population-based cohort.Participants (n = 534, aged 70 years and older) enrolled in the prospective Mayo Clinic Study of Aging were evaluated at baseline and every 15 months to identify incident MCI or dementia.Over a median follow-up of 5.1 years, 153 of 534 participants (28.7%) with prevalent or incident MCI progressed to dementia (71.3 per 1,000 person-years). The cumulative incidence of dementia was 5.4% at 1 year, 16.1% at 2, 23.4% at 3, 31.1% at 4, and 42.5% at 5 years. The risk of dementia was elevated in MCI cases (hazard ratio [HR] 23.2, p0.001) compared with CN subjects. Thirty-eight percent (n = 201) of MCI participants reverted to CN (175.0/1,000 person-years), but 65% subsequently developed MCI or dementia; the HR was 6.6 (p0.001) compared with CN subjects. The risk of reversion was reduced in subjects with an APOE ε4 allele (HR 0.53, p0.001), higher Clinical Dementia Rating Scale-Sum of Boxes (HR 0.56, p0.001), and poorer cognitive function (HR 0.56, p0.001). The risk was also reduced in subjects with amnestic MCI (HR 0.70, p = 0.02) and multidomain MCI (HR 0.61, p = 0.003).MCI cases, including those who revert to CN, have a high risk of progressing to dementia. This suggests that diagnosis of MCI at any time has prognostic value.

Objective: To estimate the incidence of and to characterize cognitive and imaging findings associated with incident amyloid PET positivity. Methods: Cognitively normal (CN) participants in the Mayo Clinic Study of Aging who had 2 or more serial imaging assessments, which included amyloid PET, FDG-PET, and MRI at each time point, were eligible for analysis (n = 207). Twelve subjects with Alzheimer disease dementia were included for comparison. Results: Of the 123 CN participants who were amyloid-negative at baseline, 26 met criteria for incident amyloid PET positivity. Compared to the 69 subjects who remained stable amyloid-negative, on average these 26 did not differ on any imaging, demographic, or cognitive variables except amyloid PET (by definition) and task-free functional connectivity, which at baseline was greater in the incident amyloid-positive group. Eleven of the 26 incident amyloid-positive subjects had abnormal hippocampal volume, FDG-PET, or both at baseline. Conclusions: The incidence of amyloid PET positivity is approximately 13% per year among CN participants over age 70 sampled from a population-based cohort. In 15/26 (58%), incident amyloid positivity occurred prior to abnormalities in FDG-PET and hippocampal volume. However, 11/26 (42%) incident amyloid-positive subjects had evidence of neurodegeneration prior to incident amyloid positivity. These 11 could be subjects with combinations of preexisting non-Alzheimer pathophysiologies and tau-mediated neurodegeneration who newly entered the amyloid pathway. Our findings suggest that both “amyloid-first” and “neurodegeneration-first” biomarker profile pathways to preclinical AD exist.

Objectives: Secondary prevention trials in subjects with preclinical Alzheimer disease may require documentation of brain amyloidosis. The identification of inexpensive and noninvasive screening variables that can identify individuals who have significant amyloid accumulation would reduce screening costs. Methods: A total of 483 cognitively normal (CN) individuals, aged 70–92 years, from the population-based Mayo Clinic Study of Aging, underwent Pittsburgh compound B (PiB)–PET imaging. Logistic regression determined whether age, sex, APOE genotype, family history, or cognitive performance was associated with odds of a PiB retention ratio >1.4 and >1.5. Area under the receiver operating characteristic curve (AUROC) evaluated the discrimination between PiB-positive and -negative subjects. For each characteristic, we determined the number needed to screen in each age group (70–79 and 80–89) to identify 100 participants with PiB >1.4 or >1.5. Results: A total of 211 (44%) individuals had PiB >1.4 and 151 (31%) >1.5. In univariate and multivariate models, discrimination was modest (AUROC ∼0.6–0.7). Multivariately, age and APOE best predicted odds of PiB >1.4 and >1.5. Subjective memory complaints were similar to cognitive test performance in predicting PiB >1.5. Indicators of PiB positivity varied with age. Screening APOE e4 carriers alone reduced the number needed to screen to enroll 100 subjects with PIB >1.5 by 48% in persons aged 70–79 and 33% in those aged 80–89. Conclusions: Age and APOE genotype are useful predictors of the likelihood of significant amyloid accumulation, but discrimination is modest. Nonetheless, these results suggest that inexpensive and noninvasive measures could significantly reduce the number of CN individuals needed to screen to enroll a given number of amyloid-positive subjects.

Objective: To examine the longitudinal association between plasma total cholesterol and triglyceride levels and incident dementia. Methods: Neuropsychiatric, anthropometric, laboratory, and other assessments were conducted for 392 participants of a 1901 to 1902 birth cohort first examined at age 70. Follow-up examinations were at ages 75, 79, 81, 83, 85, and 88. Information on those lost to follow-up was collected from case records, hospital linkage system, and death certificates. Cox proportional hazards regression examined lipid levels at ages 70, 75, and 79 and incident dementia between ages 70 and 88. Results: Increasing cholesterol levels (per mmol/L) at ages 70 (hazard ratio [HR] 0.77, 95% CI: 0.61 to 0.96, p = 0.02), 75 (HR 0.70, CI: 0.52 to 0.93, p = 0.01), and 79 (HR 0.73, CI: 0.55 to 0.98, p = 0.04) were associated with a reduced risk of dementia between ages 79 and 88. Examination of cholesterol levels in quartiles showed that the risk reduction was apparent only among the highest quartile at ages 70 (8.03 to 11.44 mmol/L [311 to 442 mg/dL]; HR 0.31, CI: 0.11 to 0.85, p = 0.03), 75 (7.03 to 9.29 mmol/L [272 to 359 mg/dL]; HR 0.20, CI: 0.05 to 0.75, p = 0.02), and 79 (6.82 to 9.10 mmol/L [264 to 352 mg/dL]; HR 0.45, CI: 0.17 to 1.23, p = 0.12). Triglyceride levels were not associated with dementia. Conclusions: High cholesterol in late life was associated with decreased dementia risk, which is in contrast to previous studies suggesting high cholesterol in mid-life is a risk factor for later dementia. The conflicting results may be explained by the timing of the cholesterol measurements in relationship to age and the clinical onset of dementia.

Objective: To identify neuroanatomical underpinnings of cognitive (COG) and neuropsychiatric (NPS) changes in Alzheimer disease (AD). Background Cross-sectional analyses have revealed correlations between COG or NPS and local brain damage in AD. Less is known about the relationship between changes in these symptoms and changes in the AD brain over time. Design/Methods: Subjects were evaluated at 2 time points, one year apart - 22 with AD dementia and 6 with mild cognitive impairment who progressed to AD dementia within a mean of 21 months. Clinical measures of COG or NPS included: mini-mental state examination (MMSE), California verbal learning test (CVLT), and neuropsychiatric inventory (NPI). COG or NPS changes between two time points [Δcog or Δnps = (baseline scale) – (scale a year later)] were calculated. Diffusion tensor images (DTI) were acquired on a 3T-scanner with a voxel size of 2.23 mm3. Fractional anisotropy (FA) and mean diffusivity (MD) were measured using atlas-based image quantification in 148 brain structures at the same two time points.FA change [ΔFA = (baseline FA) – (FA after one year)] and MD change [ΔMD = (baseline MD) – (MD after one year)] were calculated in all regions generating a 148 (# of structures) x 28 (# of patients) matrix. Principal component analysis was performed on the matrix and the principal components that significantly correlated with Δcog or Δnps (p Results: Change in CVLT short-delay free-recall was associated with MD increases in the limited areas (frontal/limbic/basal ganglia), whereas change in MMSE reflected more widespread MD increases (frontal/temporal/parietal/deep gray matters). FA reduction in specific brain regions was correlated with increases in severity for individual NPS symptoms, including: : delusions→right frontal/bilateral caudate; agitation/irritability→right fronto-temporal/parietal; hallucinations→cingulum/corpus callosum/thalamus/midbrain. Conclusions: Worsening COG and NPS reflect progressive brain damage due to AD in specific neuroanatomical structures. Supported by: KO was funded by the NIH (R21AG033774) and the Johns Hopkins Alzheimer9s Disease Research Center (P50AG005146 from NIH). SM was funded by NIH (P41 RR015241and RO1AG20012). MM was funded by the NIH (R21NS060271). The images acquired from Alzheimer9s patients and mild cognitive impairment patients were supported by a methods development grant from Glaxo-Smith-Kline, awarded to MA and CGL. Disclosure: Dr. Oishi has nothing to disclose. Dr. Mielke has nothing to disclose. Dr. Albert has received personal compensation for activities with Eisai, Genentech, and Lilly as a consultant. Dr. Albert has received research support from GE. Dr. Lyketsos has received personal compensation for activities with Pfizer, Forest, Lilly, Takeda, and Elan as a consultant.Dr. Lyketsos has received research support from Forest Laboratories. Dr. Mori has nothing to disclose.