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OBJECTIVES: To determine the extent to which preoperative performance on tests of executive function and memory was associated with delirium after coronary artery bypass graft (CABG) surgery. DESIGN: Prospective observational cohort study. SETTING: Two academic medical centers and one Department of Veterans Affairs medical center in Massachusetts. PARTICIPANTS: Eighty subjects without preoperative delirium undergoing CABG or CABG-valve surgery completed baseline neuropsychological assessments with validated measures of memory and executive function. MEASUREMENTS: Beginning on postoperative Day 2, a battery to diagnose delirium was administered daily. Confirmatory factor analysis (CFA) was used to define two cognitive domain composites (memory and executive function). The loading pattern of neuropsychological measures onto the latent cognitive domains was determined a priori. Poisson regression was used to model the association between neuropsychological performance and cognitive domain composite scores and risk of postoperative delirium. The association was expressed as the difference between impaired (0.5 standard deviations (SDs) below mean) and nonimpaired (0.5 SDs above mean) performers. RESULTS: Forty subjects (50%) developed delirium. Measures of memory function were not significantly related to delirium. Of the executive function measures, verbal fluency, category fluency, Hopkins Verbal Learning Test learning, and backward recounting of days and months were significantly related to delirium. Preoperative mental status was a strong predictor of postoperative delirium. After controlling for age, sex, education, medical comorbidity, mental status, and the other cognitive domain, CFA cognitive domain composites suggest that risk for delirium is specific for executive functioning impairment (relative risk (RR) = 2.77, 95% confidence interval (CI) = 1.12–6.87) but not for memory impairment (RR = 0.49, 95% CI = 0.19–1.25). CONCLUSION: Worse preoperative performance in executive function was independently associated with greater risk of developing delirium after CABG. [ABSTRACT FROM AUTHOR]

Efforts to conceptualize risk factors for postoperative delirium in older adults have focused on the time proximate to the episode, but how early-life exposures influence delirium risk is poorly understood. An observational cohort of 547 patients aged 70+undergoing major non-cardiac surgery at two academic medical centers in Boston. Demographic characteristics, cognition, parental education, health, and participation in cognitively stimulating activities were assessed prior to surgery. Delirium incidence and severity were measured daily during hospitalization. Higher paternal education was associated with significantly lower incidence of delirium (X2(1, N =547)=8.35, p <.001; odds ratio OR=.93, 95% CI,.87 to.98) and inversely associated with delirium severity (r(545)=−.13, p <.001). Higher maternal education was associated with lower delirium incidence but did not reach statistical significance. The effect of paternal education on delirium incidence was independent of the patient's education, estimated premorbid intelligence, medical comorbidities, neighborhood disadvantage, and participation in cognitively stimulating activities (X2(2, N =547)=31.22, p <.001). Examining early-life exposures may yield unique insights into the risks and pathogenesis of delirium. Evaluating long-term factors that increase vulnerability to delirium may improve our ability to calculate risk. It may guide clinical decision-making and inform pre- and post-operative recommendations. [ABSTRACT FROM AUTHOR]

There is a need for validated measures of attention for use in longitudinal studies of older populations. We studied 249 participants aged 80 to 101 years using the population-based MOBILIZE Boston Study. Four subscales of the Test of Everyday Attention (TEA) were included, measuring attention switching, selective, sustained and divided attention and a neuropsychological battery including validated measures of multiple cognitive domains measuring attention, executive function and memory. The TEA previously has not been validated in persons aged 80 and older. Among participants who completed the TEA, scores on other attentional measures strongly with TEA domains (R=.60-.70). Proportions of participants with incomplete TEA subscales ranged from 8% (selective attention) to 19% (attentional switching). Reasons for not completing TEA tests included failure to comprehend test instructions despite repetition and practice. These results demonstrate the challenges and potential value of the Test of Everyday Attention in studies of very old populations. [ABSTRACT FROM AUTHOR]

OBJECTIVES: To establish Montreal Cognitive Assessment (MoCA) scores that correspond to well-established cut-points on the Mini-Mental State Examination (MMSE). DESIGN: Cross-sectional observational study. SETTING: General medical service of a large teaching hospital. PARTICIPANTS: Individuals aged 75 and older (N = 199; mean age 84, 63% female). MEASUREMENTS: The MoCA (range 0-30) and the MMSE (range 0-30) were administered within 2 hours of each other. The Abbreviated MoCA (A-MoCA; range 0-22) was calculated from the full MoCA. Scores from the three tests were analyzed using equipercentile equating, a statistical method for determining comparable scores on different tests of a similar construct by estimating per-centile equivalents. RESULTS: MoCA scores were lower (mean 19.3 ± 5.8) than MMSE scores (mean 24.1 ± 6.6). Traditional MMSE cut-points of 27 for mild cognitive impairment and 23 for dementia corresponded to MoCA scores of 23 and 17, respectively. CONCLUSION: Scores on the full and abbreviated versions of the MoCA can be linked directly to the MMSE. The MoCA may be more sensitive to changes in cognitive performance at higher levels of functioning. [ABSTRACT FROM AUTHOR]

Objectives To examine baseline (preoperative) neuropsychological test performance in a cohort of elderly individuals undergoing elective surgery and the association between specific neuropsychological domains and postoperative delirium. Design Ongoing prospective cohort study. Setting Successful Aging after Elective Surgery Study. Participants Elderly adults (N = 300) scheduled for elective (noncardiac) surgery. Measurements Neuropsychological testing, including standardized assessments of memory, divided and sustained attention, speed of mental processing, verbal fluency, working memory, language, and an overall measure of premorbid cognitive functioning, was performed 2 to 4 weeks before surgery. The relationship between the individual neuropsychological tests and delirium status was examined using linear regression, adjusting for age, sex, and education. Results Study participants were generally highly educated (mean years of education 15.0 ± 2.9), with minimal or no cognitive impairment (mean Modified Mini-Mental State Examination score 93.2 out of 100). After adjustment, participants who developed postoperative delirium had performed significantly lower preoperatively on measures of speed of mental processing and divided attention (Trail-Making Test Part B, mean difference 17.55, P = .02), category fluency (animal naming, mean difference −1.94, P = .01), sustained visual attention (Visual Search and Attention, mean difference −3.19, P < .001), and working memory with new learning and recall (Hopkins Verbal Learning Test-Revised Total mean difference −0.53 to −0.79, P < .01). Conclusion Individuals who later develop delirium have lower scores on tests evaluating the areas of complex attention, executive functioning, and rapid access to verbal knowledge or semantic networks at baseline. Future studies to better understand how the cognitive profiles identified may predispose individuals to developing delirium may help pave the way to greater understanding of the mechanisms of delirium. [ABSTRACT FROM AUTHOR]