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OBJECTIVE Autonomic nervous system dysfunction is associated with impaired glucose metabolism, but the temporality of this association remains unclear in individuals without diabetes. We investigated the association of autonomic function with 5-year changes in glucose metabolism in individuals without diabetes. RESEARCH DESIGN AND METHODS Analyses were based on 9,000 person-examinations for 3,631 participants without diabetes in the Whitehall II cohort. Measures of autonomic function included 5-min resting heart rate and six heart rate variability (HRV) indices. Associations between baseline autonomic function measures and 5-year changes in fasting and 2-h plasma glucose, serum insulin concentrations, insulin sensitivity (insulin sensitivity index [ISI0–120] and HOMA of insulin sensitivity), and β-cell function (HOMA of β-cell function) were estimated in models adjusting for age, sex, ethnicity, metabolic factors, and medication. RESULTS A 10-bpm higher resting heart rate was associated with 5-year changes in fasting and 2-h insulin and ISI0–120 of 3.3% change (95% CI 1.8; 4.8), P < 0.001; 3.3% change (1.3; 5.3), P = 0.001; and −1.4% change (−2.4; −0.3), P = 0.009, respectively. In models adjusted for age, sex, and ethnicity, higher baseline values of several HRV indices were associated with a 5-year decrease in fasting and 2-h insulin and ISI0–120. However, significance was lost by full adjustment. A majority of HRV indices exhibited a trend toward higher values being associated with lower insulin levels and higher insulin sensitivity. CONCLUSIONS Higher resting heart rate in individuals without diabetes is associated with future unfavorable changes in insulin levels and insulin sensitivity. Associations may be mediated via autonomic function; however, results are inconclusive. Resting heart rate may be a risk marker for future pathophysiological changes in glucose metabolism.

Objective Symptoms indicative of diabetic polyneuropathy (DPN) early in type 2 diabetes may act as a marker for cardiovascular disease (CVD) and death. Research Design and Methods We linked data from two Danish type 2 diabetes cohorts, ADDITION-Denmark and DD2, to national healthcare registers. The Michigan Neuropathy Screening Instrument questionnaire (MNSIq) was completed at diabetes diagnosis in ADDITION-Denmark and at a median of 4.6 years after diagnosis of diabetes in DD2. An MNSIq score ≥ 4 was considered as indicative of DPN. Using Poisson regressions, we computed incidence rate ratios of CVD and all-cause mortality comparing MNSIq scores ≥ 4 with scores < 4. Analyses were adjusted for a range of established CVD risk factors. Results In total, 1,445 (ADDITION-Denmark) and 5,028 (DD2) individuals were included in the study. Compared with MNSIq scores < 4, MNSIq scores ≥ 4 were associated with higher incidence rate of CVD, with incidence rate ratios (IRRs) of 1.79 [95% confidence interval (CI) 1.38-2.31] in ADDITION-Denmark, 1.57 (CI: 1.27-1.94) in the DD2, and a combined IRR of 1.65 (CI: 1.41-1.95) in a fixed-effect meta-analysis. MNSIq scores ≥ 4 did not associate with mortality; combined mortality rate ratio 1.11 (CI: 0.83-1.48). Conclusions The MNSIq may be a tool to identify a subgroup within individuals with newly diagnosed type 2 diabetes who has a high incidence rate of subsequent CVD. MNSIq scores ≥ 4, indicating DPN, were associated with a markedly higher incidence rate of CVD, beyond that conferred by established CVD risk factors.

OBJECTIVE Higher resting heart rate (rHR) and lower heart rate variability (HRV) are associated with increased risk of cardiovascular disease (CVD) and all-cause mortality in people with and without diabetes. It is unknown whether temporal changes in rHR and HRV may contribute to this risk. We investigated associations between 5-year changes in rHR and HRV and risk of future CVD and death, taking into account participants’ baseline glycemic state. RESEARCH DESIGN AND METHODS In this prospective, population-based cohort study we investigated 4,611 CVD-free civil servants (mean [SD] age, 60 [5.9] years; 70% men). We measured rHR and/or six indices of HRV. Associations of 5-year change in 5-min rHR and HRV with fatal and nonfatal CVD and all-cause mortality or the composite of the two were assessed, with adjustments made for relevant confounders. Effect modification by glycemic state was tested. RESULTS At baseline, 63% of participants were normoglycemic, 29% had prediabetes, and 8% had diabetes. During a median (interquartile range) follow-up of 11.9 (11.4; 12.3) years, 298 participants (6.5%) experienced a CVD event and 279 (6.1%) died of non–CVD-related causes. We found no association between 5-year changes in rHR and HRV and future events. Only baseline rHR was associated with all-cause mortality. A 10 bpm–higher baseline HR level was associated with an 11.4% higher rate of all-cause mortality (95% CI 1.0–22.9%; P = 0.032). Glycemic state did not modify associations. CONCLUSIONS Changes in rHR and HRV and possibly also baseline values of these measures are not associated with future CVD or death in people with or without dysglycemia.

OBJECTIVE To examine the course of cardiovascular autonomic neuropathy (CAN) and related cardiometabolic risk factors in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS CAN and cardiometabolic risk factors were assessed in the Danish arm of the Anglo-Danish-Dutch Study of Intensive Treatment in People With Screen-Detected Diabetes in Primary Care (ADDITION-Denmark) at 6-year (n = 777) and 13-year (n = 443) follow-up examinations. Cardiovascular autonomic reflex tests (CARTs)—that is, lying to standing, deep breathing, and the Valsalva maneuver—and 2-min resting heart rate variability (HRV) indices were obtained as the main measures of CAN. Risk factors related to CAN status, as determined by CARTs, were studied by using multivariate logistic regressions. The effects of risk factors on continuous CARTs and HRV indices, and their changes over time, were estimated in linear mixed models. RESULTS A progressive yet heterogeneous course of CAN occurred between the 6- and 13-year follow-ups. Higher HbA1c, weight, BMI, and triglycerides were associated with prevalent CAN. No significant effect of risk factors on CARTs was found when they were analyzed as continuous variables. CART indices decreased over time, and a trend of decreasing HRV indices was seen. Higher HbA1c and BMI were associated with lower HRV index values, but these differences diminished over time. CONCLUSIONS These data confirm that hyperglycemia, obesity, and hypertriglyceridemia are negatively related to indices of CAN, although these effects diminish over time. The observed heterogeneous course of CAN may challenge the present clinical approach of categorically classifying CARTs to diagnose CAN and the notion of CAN being irreversible.

Background: We assessed the effect of parental and sibling age at diabetes diagnosis on index individuals’ risk of developing diabetes. Methods: We carried out a register-based closed cohort analysis of 869,489 initially diabetes-free index individuals living in Denmark between 1995 and 2012. We assessed the effect of parents’ and full siblings’ age at diabetes diagnosis on the incidence of diabetes in the index individual, beyond the general effect of a positive family history. We calculated incidence rate ratios (IRR) in sex-stratified Poisson regression models. Results: A total of 58,339 index individuals developed diabetes during 14 million person-years of follow-up. Diabetes risk was highest when parents had a diabetes diagnosis at a younger age. Men and women with a mother diagnosed with diabetes at age 50 had an IRR of 3.62 (95% CI: 2.86 to 4.57) and 5.03 (95% CI: 3.90 to 6.49) respectively compared to people of the same age and sex without a mother with diabetes. At a maternal diagnosis age of 70, the IRRs were 1.56 (95% CI: 1.46 to 1.57) and 1.67 (95% CI: 1.53 to 1.82) for men and women respectively. Conclusions: Diabetes early detection strategies might consider that younger parental age at diabetes diagnosis may reflect more severe forms of diabetes, conferring a higher risk of developing the disease. Disclosure J. Silverman Retana: Other Relationship; Self; Danish Diabetes Academy, Steno Diabetes Center Aarhus. A. Hulman: None. J. NIelsen: None. B. Carstensen: Consultant; Self; Leo Pharma. Speaker's Bureau; Self; Novo Nordisk A/S. Stock/Shareholder; Self; Novo Nordisk Inc. R.K. Simmons: None. L. Bjerg: None. L. Johnston: None. D.R. Witte: None. Funding Danish Diabetes Academy (to J.O.S.R.); Novo Nordisk Foundation; Steno Diabetes Center Aarhus

Objective: To examine 18-year trends in early A1C and lipid control among patients initiating first-time glucose-lowering drug therapy (GLD) for type 2 diabetes. Materials and Methods: Population-based sequential cross-sectional study using healthcare databases covering Northern Denmark (∼1.8 million persons). For all 94,175 GLD initiators during 2000-2017, we examined likelihood of A1C and lipid testing, antilipid therapy, and 1-year glycemic and LDL cholesterol target achievement. Results: The proportion of patients with at least one A1C test increased from 53% in 2000 to 95% in 2017 (Figure, Panel A). Lipid testing increased from 82% to 98% and lipid lowering therapy initiation quintupled from 12% to 61%. Mean pre-treatment A1C declined substantially, from 9.2% (77 mmol/mol) to 7.3% (56 mmol/mol) in 2011, then rose to 7.9% (63 mmol/mol) in 2017 (Panel B). Post-treatment A1C decreased less; pre- and post-treatment LDL cholesterol declined similarly. The proportion of patients achieving glycemic and cholesterol targets increased substantially over time (Panel C). Conclusion: Monitoring and treatment of A1C and cholesterol in early type 2 diabetes have improved considerably over the past 18 years, while quality improvement was somewhat flat after the 2011 change in diagnostic criteria. Disclosure J.S. Knudsen: None. D.R. Witte: None. A. Hulman: None. P.F. Rønn: Research Support; Self; Amgen AB. Stock/Shareholder; Spouse/Partner; Novo Nordisk A/S. T. Lauritzen: Advisory Panel; Self; AstraZeneca. Board Member; Self; Novo Nordisk A/S. H.T. Sôrensen: None. R.W. Thomsen: None. Funding Aarhus University

Hyperinsulinemia is an adaptive mechanism that enables the maintenance of normoglycemia in the presence of insulin resistance. We assessed whether glucagon is also involved in the adaptation to insulin resistance. A total of 1,437 individuals underwent an oral glucose tolerance test with measurements of circulating glucose, insulin, and glucagon concentrations at 0, 30 and 120 min. Early glucagon suppression was defined as suppression in the period from 0 to 30 min, and late glucagon suppression as 30 to 120 min after glucose intake. Insulin sensitivity was estimated by the validated insulin sensitivity index. Individuals with screen-detected diabetes had 30% higher fasting glucagon levels and diminished early glucagon suppression, but greater late glucagon suppression when compared with individuals with normal glucose tolerance (P ≤ 0.014). Higher insulin resistance was associated with higher fasting glucagon levels, less early glucagon suppression, and greater late glucagon suppression (P < 0.001). The relationship between insulin sensitivity and fasting glucagon concentrations was nonlinear (P < 0.001). In conclusion, increased fasting glucagon levels and delayed glucagon suppression, together with increased circulating insulin levels, develop in parallel with insulin resistance. Therefore, glucose maintenance during insulin resistance may depend not only on hyperinsulinemia but also on the ability to suppress glucagon early after glucose intake.

The role of glucose-stimulated release of glucagon-like peptide-1 (GLP-1) in the development of obesity and type 2 diabetes is unclear. We assessed GLP-1 response to oral glucose in a large study population of lean and obese men and women with normal and impaired glucose regulation. Circulating concentrations of glucose, insulin and GLP-1 during an oral glucose tolerance test (OGTT) were analyzed in individuals with normal glucose tolerance (NGT, n=774), pre-diabetes (n=523) or screen-detected type 2 diabetes (n=163) who attended the Danish ADDITION-PRO study (n=1,462). Compared with individuals with NGT, women with pre-diabetes or type 2 diabetes had 25% lower GLP-1 response to an OGTT, and both men and women with pre-diabetes or type 2 diabetes had 16-21% lower 120-min GLP-1 concentrations independent of age and obesity. Obese and overweight individuals had 20% reduced GLP-1 response to oral glucose compared with normal weight individuals independent of glucose tolerance status. Higher GLP-1 responses were associated with better insulin sensitivity and beta cell function, higher age and lower degree of obesity. Our findings indicate that a reduction in GLP-1 response to oral glucose occurs prior to the development of type 2 diabetes and obesity, which can have consequences for early prevention strategies for diabetes.

OBJECTIVE Aortic stiffness is an important predictor of future morbidity and mortality. Diabetes is associated with increased aortic stiffness, but the importance of nondiabetic glucometabolic status for accelerated aortic stiffening is unclear. We tested the hypothesis that adverse glucometabolic status is associated with accelerated aortic stiffening in individuals without diabetes, independently of known risk factors for arterial stiffening. RESEARCH DESIGN AND METHODS Glucometabolic status and other cardiovascular risk factors were assessed at baseline in 2008–09, and carotid femoral pulse wave velocity (cfPWV) at baseline and follow-up in 2012–13, in 4,386 participants without diabetes of the Whitehall II Study. RESULTS The mean age of the cohort at cfPWV baseline was 60 years, and 74% were male. cfPWV increased from (mean ± SE) 8.30 ± 0.03 to 8.98 ± 0.04 m/s during 4 years of follow-up. At baseline, cfPWV was associated with fasting and 2-h postload glucose, HbA1c, and HOMA-insulin resistance (HOMA-IR). HbA1c and HOMA-IR were associated with progression of cfPWV after adjusting for physiological confounders and cardiovascular risk factors. A 1 SD higher HbA1c and HOMA-IR were associated with greater increases in cfPWV (0.11 m/s per 5 years [95% CI 0.04, 0.18], P = 0.003 and 0.09 m/s per 5 years [0.01, 0.17], P = 0.03, respectively). Additional adjustment for BMI weakened the association with HOMA-IR but not with HbA1c. CONCLUSIONS HbA1c is independently associated with accelerated progression of aortic stiffness in individuals without diabetes. These findings suggest that long-term glucometabolic status, even in individuals without diabetes, could be an important target for preventative strategies against vascular aging.

The pro-inflammatory cytokine interleukin (IL)-1β is implicated in the development of insulin resistance and beta-cell dysfunction, whereas higher circulating IL-1 receptor antagonist (IL-1RA - an endogenous inhibitor of IL-1β - has been suggested to improve glycemia and beta-cell function in patients with type 2 diabetes. In order to elucidate the protective role of IL-1RA, this study aimed to identify genetic determinants of circulating IL-1RA concentration and to investigate their associations with immunological and metabolic variables related to cardiometabolic risk. In the analysis of 7 discovery and 4 replication cohort studies, two single nucleotide polymorphisms (SNPs) were independently associated with circulating IL-1RA concentration (rs4251961 at the IL-1RN locus, n=13,955, P=2.76x10(-21); and rs6759676, closest gene locus IL1F10, n=13,994, P=1.73x10(-17)). The proportion of the variance in IL-1RA explained by both SNPs combined was 2.0%. IL-1RA-raising alleles of both SNPs were associated with lower circulating C-reactive protein concentration. The IL-1RA-raising allele of rs6759676 was also associated with lower fasting insulin and lower homeostasis model assessment insulin resistance (HOMA-IR). In conclusion, we show that circulating IL-1RA levels are predicted by two independent SNPs at the IL-1RN and IL-1F10 loci and that genetically raised IL-1RA may be protective against the development of insulin resistance.

OBJECTIVE Regular physical activity (PA) reduces the risk of developing type 2 diabetes, and different subtypes of dysglycemia have shown different associations with PA. To better understand the associations of PA and glucose homeostasis, we examined the association of objectively measured PA energy expenditure (PAEE) with detailed measures of glucose homeostasis. RESEARCH DESIGN AND METHODS In 1,531 men and women, with low to high risk of developing type 2 diabetes, we measured 7 days of PAEE using a combined accelerometry and heart rate monitor (ActiHeart). Measures and indices of glucose homeostasis were derived from a 3-point oral glucose tolerance test in addition to measures of long-term glycemia (glycated hemoglobin A1c and advanced glycation end products). Associations of PAEE with glucose homeostasis markers were examined using linear regression models. RESULTS Median age (IQR) was 66.6 years (62.1–71.6) (54% men) with a median ActiHeart wear time of 6.9 days (6.0–7.1) and PAEE level of 33.0 kJ/kg/day (23.5–46.1). In fully adjusted models, we found higher levels of PAEE to be positively associated with insulin sensitivity and negatively with insulin 2 h after glucose load (P < 0.05). CONCLUSIONS Even in an elderly population with low levels of PA, we found higher objectively measured PAEE levels to be associated with a more beneficial glucose metabolic profile. Although our findings are cross-sectional, they indicate that even without high-intensity exercise, increasing the overall level of PAEE slightly in an entire population at risk for developing type 2 diabetes may be a realistic and worthwhile goal to reach in order to achieve beneficial effect in terms of glucose metabolism.

OBJECTIVE The role of adiponectin in the natural history of diabetes is not well characterized. We set out to characterize prediagnosis trajectories of adiponectin in individuals who develop type 2 diabetes. RESEARCH DESIGN AND METHODS In a case-cohort study (335 incident diabetes case and 2,474 noncase subjects) nested in the Whitehall II study, serum adiponectin was measured up to three times per participant (1991–1993, 1997–1999, and 2003–2004). Multilevel models adjusted for age and ethnicity were fitted to assess 13-year trajectories of log-transformed adiponectin preceding diabetes diagnosis or a randomly selected time point during follow-up (year0) based on 755/5,095 (case/noncase) person-examinations. RESULTS Adiponectin levels were lower in diabetes case than in noncase subjects (median 7,141 [interquartile range 5,187–10,304] vs. 8,818 [6,535–12,369] ng/mL at baseline, P < 0.0001). Control subjects showed a modest decline in adiponectin throughout follow-up (0.3% per year, P < 0.0001) at higher levels in women than in men (difference at year0: 5,358 ng/mL, P < 0.0001). Female case and early-onset case (age at diagnosis CONCLUSIONS Lower adiponectin levels were observed already a decade before the diagnosis of diabetes. The marked sex difference in trajectories suggests that sex-specific mechanisms affect the association between adiponectin levels and diabetes development.

OBJECTIVE Diabetes is associated with increased brachial and central blood pressure and aortic stiffness. We examined the effect of intensive multifactorial treatment in general practice on indices of peripheral and central hemodynamics among patients with screen-detected diabetes. RESEARCH DESIGN AND METHODS As part of a population-based screening and intervention study in general practice, 1,533 Danes aged 40–69 years were clinically diagnosed with screen-detected diabetes. General practitioners were randomized to provide intensive multifactorial treatment or routine care. After a mean follow-up of 6.2 years, an unselected subsample of 456 patients underwent central hemodynamic assessments by applanation tonometry. Central pressure was derived from the radial pulse wave. Aortic stiffness was assessed as carotid-femoral pulse wave velocity (aPWV). The intervention effect on each index of central hemodynamics was analyzed by mixed-effects models adjusted for heart rate, cluster randomization, age, and sex. RESULTS At screening, median age was 59.2 years (interquartile range 55.2–64.6); 289 patients (63%) were in the intensive treatment group, and 278 patients (61%) were men. Patients in the intensive treatment group had a 0.51 m/s (95% CI −0.96 to −0.05, P = 0.03) lower aPWV compared with routine care. Respective differences for central augmentation index (−0.84% [−2.54 to 0.86]), pulse pressure (0.28 mmHg [−1.75 to 2.32]), and systolic (−1.42 mmHg [−4.47 to 1.64]) and diastolic (−1.79 mmHg [−3.72 to 0.14]) blood pressure were not statistically significant. CONCLUSIONS Intensive multifactorial treatment of screen-detected diabetes during 6 years in general practice has a significant impact on aortic stiffness, whereas the effects on other hemodynamic measures are smaller and not statistically significant.

OBJECTIVE Circulating levels of NH2-terminal probrain natriuretic peptide (NT-proBNP), a marker of acute heart failure, are associated with increased risk of cardiovascular disease (CVD) in the general population. However, there is little information on the potential role of NT-proBNP as a biomarker of vascular complications in type 1 diabetic patients. We investigated whether serum NT-proBNP levels were associated with micro- and macrovascular disease in type 1 diabetic subjects. RESEARCH DESIGN AND METHODS A cross-sectional nested case-control study from the EURODIAB Prospective Complications Study of 507 type 1 diabetic patients was performed. Case subjects (n = 345) were defined as those with one or more complications of diabetes; control subjects (n = 162) were those with no evidence of any complication. We measured NT-proBNP levels by a two-site sandwich electrochemiluminescence immunoassay and investigated their associations with complications. RESULTS Mean NT-proBNP levels were significantly higher in case than in control subjects. In logistic regression analyses, NT-proBNP values >26.46 pg/mL were independently associated with a 2.56-fold increased risk of all complications. Odds ratios of CVD (3.95 [95% CI 1.26–12.35]), nephropathy (4.38 [1.30–14.76]), and distal symmetrical polyneuropathy (4.32 [1.41–13.23]) were significantly increased in patients with NT-proBNP values in the highest quartile (>84.71 pg/mL), independently of renal function and known risk factors. These associations were no longer significant after inclusion of TNF-α into the model. CONCLUSIONS In this large cohort of type 1 diabetic subjects, we found an association between NT-proBNP and diabetic micro- and macrovascular complications. Our results suggest that the inflammatory cytokine TNF-α may be involved in this association.

OBJECTIVE There is limited evidence on how intensive multifactorial treatment (IT) improves outcomes of diabetes when initiated in the lead time between detection by screening and diagnosis in routine clinical practice. We examined the effects of early detection and IT of type 2 diabetes in primary care on the prevalence of diabetic peripheral neuropathy (DPN) and peripheral arterial disease (PAD) 6 years later in a pragmatic, cluster-randomized parallel group trial. RESEARCH DESIGN AND METHODS A stepwise screening program in 190 general practices in Denmark was used to identify 1,533 people with type 2 diabetes. General practices were randomized to deliver either IT or routine care (RC) as recommended through national guidelines. Participants were followed for 6 years and measures of DPN and PAD were applied. RESULTS We found no statistically significant effect of IT on the prevalence of DPN and PAD compared with RC. The prevalence of an ankle brachial index ≤0.9 was 9.1% (95% CI 6.0–12.2) in the RC arm and 7.3% (5.0–9.6) in the IT arm. In participants tested for vibration detection threshold and light touch sensation, the prevalence of a least one abnormal test was 34.8% (26.7–43.0) in the RC arm and 30.1% (24.1–36.1) in the IT arm. CONCLUSIONS In a population with screen-detected type 2 diabetes, we did not find that screening followed by IT led to a statistically significant difference in the prevalence of DPN and PAD 6 years after diagnosis. However, treatment levels were high in both groups.

OBJECTIVE In the general, nondiabetic population, fasting glucose increases only slightly over time, whereas 2-h postload glucose shows a much steeper age-related rise. The reasons underlying these different age trajectories are unknown. We investigated whether common genetic variants associated with fasting and 2-h glucose contribute to age-related changes of these traits. RESEARCH DESIGN AND METHODS We studied 5,196 nondiabetic participants of the Whitehall II cohort (aged 40–78 years) attending up to four 5-yearly oral glucose tolerance tests. A genetic score was calculated separately for fasting and 2-h glucose, including 16 and 5 single nucleotide polymorphisms, respectively. Longitudinal modeling with age centered at 55 years was used to study the effects of each genotype and genetic score on fasting and 2-h glucose and their interactions with age, adjusting for sex and time-varying BMI. RESULTS The fasting glucose genetic score was significantly associated with fasting glucose with a 0.029 mmol/L (95% CI 0.023–0.034) difference (P = 2.76 × 10−21) per genetic score point, an association that remained constant over time (age interaction P = 0.17). Two-hour glucose levels differed by 0.076 mmol/L (0.047–0.105) per genetic score point (P = 3.1 × 10−7); notably, this effect became stronger with increasing age by 0.006 mmol/L (0.003–0.009) per genetic score point per year (age interaction P = 3.0 × 10−5), resulting in diverging age trajectories by genetic score. CONCLUSIONS Common genetic variants contribute to the age-related rise of 2-h glucose levels, whereas associations of variants for fasting glucose are constant over time, in line with stable age trajectories of fasting glucose.

OBJECTIVE Slow nerve conduction velocity and reduction in response amplitude are objective hallmarks of diabetic sensorimotor polyneuropathy. Because subjective or clinical indicators of neuropathy do not always match well with the presence of abnormal nerve physiology tests, we evaluated associations to nerve conduction in patients with type 1 diabetes. RESEARCH DESIGN AND METHODS Nerve conduction studies were performed in the distal sural and ulnar sensory nerves and the peroneal motor nerve in 456 individuals with type 1 diabetes who participated in the follow-up visit of the EURODIAB Prospective Complications Study (EPCS). We used multivariate regression models to describe associations to decreased nerve conduction measures. RESULTS In addition to an effect of duration of diabetes and A1C, which were both associated with low nerve conduction velocity and response amplitude, we found that the presence of nephropathy, retinopathy, or a clinical diagnosis of neuropathy was associated with low nerve conduction velocity and amplitude. In the case of nonproliferative retinopathy, the odds ratio (OR) for being in lowest tertile was 2.30 (95% CI 1.13–4.67) for nerve conduction velocity. A similar OR was found for each 2% difference in A1C (2.39 [1.68–3.41]). CONCLUSIONS We show that the presence of other microvascular diabetes complications, together with diabetes duration and A1C, are associated with low nerve conduction velocity and amplitude response and that cardiovascular disease or risk factors do not seem to be associated with these measures.

OBJECTIVE To examine antidepressant use before and after the diagnosis of diabetes. RESEARCH DESIGN AND METHODS This study was a longitudinal analysis of diabetic and nondiabetic groups selected from a prospective cohort study of 151,618 men and women in Finland (the Finnish Public Sector Study, 1995–2005). We analyzed the use of antidepressants in those 493 individuals who developed type 2 diabetes and their 2,450 matched nondiabetic control subjects for each year during a period covering 4 years before and 4 years after the diagnosis. For comparison, we undertook a corresponding analysis on 748 individuals who developed cancer and their 3,730 matched control subjects. RESULTS In multilevel longitudinal models, the odds ratio for antidepressant use in those who developed diabetes was 2.00 (95% CI 1.57–2.55) times greater than that in nondiabetic subjects. The relative difference in antidepressant use between these groups was similar before and after the diabetes diagnosis except for a temporary peak in antidepressant use at the year of the diagnosis (OR 2.66 [95% CI 1.94–3.65]). In incident cancer case subjects, antidepressant use substantially increased after the cancer diagnosis, demonstrating that our analysis was sensitive for detecting long-term changes in antidepressant trajectories when they existed. CONCLUSIONS Awareness of the diagnosis of type 2 diabetes may temporarily increase the risk of depressive symptoms. Further research is needed to determine whether more prevalent use of antidepressants noted before the diagnosis of diabetes relates to effects of depression, side effects of antidepressant use, or a common causal pathway for depression and diabetes.

OBJECTIVE Various methods are used to quantify postprandial glycemia or glucose variability, but few have been compared and none are standardized. Our objective was to examine the relationship among common indexes of postprandial glycemia, overall hyperglycemia, glucose variability, and A1C using detailed glucose measures obtained during everyday life and to study which blood glucose values of the day provide the strongest prediction of A1C. RESEARCH DESIGN AND METHODS In the A1C-Derived Average Glucose (ADAG) study, glucose levels were monitored in 507 participants (268 type 1 diabetic, 159 type 2 diabetic, and 80 nondiabetic subjects) with continuous glucose monitoring (CGM) and frequent self-monitoring of blood glucose (SMBG) during 16 weeks. We calculated several indexes of glycemia and analyzed their intercorrelations. The association between glucose measurements at different times of the day (pre- and postprandial) and A1C was examined using multiple linear regression. RESULTS Indexes of glucose variability showed strong intercorrelation. Among postprandial indexes, the area under the glucose curve calculated from CGM 2 h after a meal correlated well with the 90-min SMBG postprandial measurements. Fasting blood glucose (FBG) levels were only moderately correlated with indexes of hyperglycemia and average or postprandial glucose levels. Indexes derived with SMBG strongly correlated with those from CGM. Some SMBG time points had a stronger association with A1C than others. Overall, preprandial glucose values had a stronger association with A1C than postprandial values for both diabetes types, particularly for type 2 diabetes. CONCLUSIONS Indexes of glucose variability and average and postprandial glycemia intercorrelate strongly within each category. Variability indexes are weakly correlated with the other categories, indicating that these measures convey different information. FBG is not a clear indicator of general glycemia. Preprandial glucose values have a larger impact on A1C levels than postprandial values.

OBJECTIVE Although interleukin-1 receptor antagonist (IL-1Ra) treatment is associated with improved β-cell function and glycemic control in patients with type 2 diabetes, its role in the development of type 2 diabetes remains unclear. We used repeated measurements to characterize IL-1Ra trajectories in individuals who developed type 2 diabetes. RESEARCH DESIGN AND METHODS This case-cohort study, nested within the Whitehall II cohort, was based on 335 incident type 2 diabetes cases and 2,475 noncases. We measured serum IL-1Ra levels at up to three time points per individual and estimated retrospective trajectories of IL-1Ra before diabetes diagnosis (case subjects) or end of follow-up (control subjects) using multilevel analysis. Models were adjusted for age, sex, and ethnicity. RESULTS IL-1Ra levels were already higher in the case than control subjects 13 years before diabetes diagnosis/end of follow-up (mean [95% CI] 302 [290–314] vs. 244 [238–249] pg/ml). In control subjects, IL-1Ra levels showed a modest linear increase throughout the study period. In case subjects, IL-1Ra trajectories were parallel to those in control subjects until 6 years (95% CI 7.5–4.5) before diagnosis and then rose steeply to 399 (379–420) pg/ml at the time of diagnosis (P < 0.0001 for slope difference). Adjustment for BMI and waist circumference as time-varying covariates had little impact on these trajectories. CONCLUSIONS We show elevated IL-1Ra levels for 13 years and an accelerated increase during the last 6 years before type 2 diabetes diagnosis, indicating the presence of an anti-inflammatory response that may act to counterbalance the metabolic and immunologic disturbances that precede type 2 diabetes.

OBJECTIVE To investigate the effect of psychosocial stress at work on risk of type 2 diabetes, adjusting for conventional risk factors, among a sample of British, white-collar, middle-aged men and women. RESEARCH DESIGN AND METHODS This was a prospective analysis (1991–2004) from the Whitehall II cohort study. The current sample consists of 5,895 Caucasian middle-aged civil servants free from diabetes at baseline. Type 2 diabetes was ascertained by an oral glucose tolerance test supplemented by self-reports at baseline and four consecutive waves of data collection including two screening phases. The job strain and iso-strain models were used to assess psychosocial work stress. RESULTS Iso-strain in the workplace was associated with a twofold higher risk of type 2 diabetes in age-adjusted analysis in women but not in men (hazard ratio 1.94 [95% CI 1.17–3.21). This effect remained robust to adjustment for socioeconomic position and outside work stressors and was only attenuated by 20% after adjustment for health behaviors, obesity, and other type 2 diabetes risk factors. CONCLUSIONS Psychosocial work stress was an independent predictor of type 2 diabetes among women after a 15-year follow-up. This association was not explained by potential confounding and mediating factors. More evidence from prospective studies using the same work stress models is needed to support the current findings and provide further information on sex differences.

OBJECTIVE—Heat shock protein 27 (HSP27) is a member of the small heat shock protein family of proteins. HSP27 expression is enhanced in target tissues of diabetic microvascular complications, and changes in circulating serum HSP27 levels (sHSP27) have been reported in patients with macrovascular disease. We investigated whether sHSP27 levels were associated with micro- and macrovascular complications in type 1 diabetic patients. RESEARCH DESIGN AND METHODS—A cross-sectional, nested, case-control study from the EURODIAB Prospective Complications Study of 531 type 1 diabetic patients was performed. Case subjects (n = 363) were defined as those with one or more complications of diabetes; control subjects (n = 168) were defined as those with no evidence of any complication. We measured sHSP27 levels and investigated their associations with diabetes complications. RESULTS—Mean sHSP27 levels were significantly higher in case subjects with distal symmetrical polyneuropathy (DSP) than in control subjects, even after adjustment for age and albumin excretion rate (AER) (785.9 vs. 574.7 pg/ml, P = 0.03). In logistic regression analysis, sHSP27 levels in the upper quartile were associated with a twofold increased odds ratio (OR) of DSP, independently of conventional risk factors, markers of inflammation, and AER (OR 2.41 [95% CI 1.11–5.24]). CONCLUSIONS—In this large cohort of type 1 diabetic subjects, we found an independent association between sHSP27 and DSP. This suggests that sHSP27 levels may be a novel marker for diabetic neuropathy.

OBJECTIVE—The pathogenesis of diabetic peripheral neuropathy (DPN) is poorly understood. We have recently reported a significant reduction in spinal cord cross-sectional area at the stage of clinically detectable DPN. In this study, we investigated whether spinal cord atrophy occurs in early (subclinical) DPN. RESEARCH DESIGN AND METHODS—Eighty-one male type 1 diabetic subjects, 24 nondiabetic control subjects, and 8 subjects with hereditary sensory motor neuropathy (HSMN) type 1A underwent detailed clinical and neurophysiological assessments. Diabetic subjects were subsequently divided into three groups based on neuropathy severity (19 with no DPN, 23 with subclinical DPN, and 39 with clinically detectable DPN). All subjects underwent magnetic resonance imaging of the cervical spine and cord area measurements at disc level C2/C3. RESULTS—Mean corrected spinal cord area index (SCAI) (corrected for age, height, and weight) was 67.5 mm [95% CI 64.1–70.9] in diabetic subjects without DPN. Those with subclinical (62.4 mm [59.5–65.3]) and clinically detectable DPN (57.2 mm [54.9–59.6]) had lower mean SCAIs compared with subjects with no DPN (P = 0.03 and P < 0.001, respectively). No significant difference was found between diabetic subjects without DPN and nondiabetic control subjects (69.2 mm [66.3–72.0], P = 0.47). Mean SCAIs in subjects with HSMN type 1A (71.07 mm [65.3–76.9]) were not significantly different from those for nondiabetic control subjects and diabetic subjects without DPN. Among diabetic subjects, SCAI was significantly related to sural sensory conduction velocities and the Neuropathy Composite and Symptom Scores. CONCLUSIONS—Spinal cord involvement occurs early in DPN. There is also a significant relation between reduction in SCAI and neurophysiological assessments of DPN.

OBJECTIVE—Glucose intolerance is a risk factor for coronary disease, but there is uncertainty about the shape of the dose-response relationship between glucose level and risk of coronary mortality. We examined the prospective relation of 2-h postload blood glucose (2hBG) with coronary and other major causes of mortality over 33 years. RESEARCH DESIGN AND METHODS—A 50-g oral glucose tolerance test (OGTT) was performed at baseline (1967–1969) in 17,869 male civil servants aged 40–64 years. RESULTS—There were 3,561 coronary deaths during 451,787 person-years of observation. All-cause, cardiovascular, and respiratory mortality were elevated among participants with glucose intolerance. The hazard of coronary mortality rose from 2hBG = 4.6 mmol/l (83 mg/dl [95% CI 4.2–5.3]). The dose-response relation was best fitted by a single slope above this level, with no evidence of nonlinearity, compared with Cox models using other threshold levels, and those containing log 2hBG terms. There was no evidence for a dose-response relationship below 2hBG = 4.6 mmol/l. Between this level and 11.1 mmol/l (200 mg/dl), the age-adjusted hazard ratio was 3.62 (95% CI 2.3–5.6). The graded relationship was attenuated by 45% after adjustment for baseline coronary heart disease (CHD), BMI, systolic blood pressure, blood cholesterol, smoking, physical activity, lung function, and employment grade. CONCLUSIONS—A threshold model with linear slope best described the dose-response relationship between postload blood glucose and CHD mortality risk.

OBJECTIVE To compare screen-detected diabetes prevalence and the degree of diagnostic agreement by ethnicity with the current oral glucose tolerance test (OGTT)-based and newly proposed A1C-based diagnostic criteria. RESEARCH DESIGN AND METHODS Six studies (1999–2009) from Denmark, the U.K., Australia, Greenland, Kenya, and India were tested for the probability of an A1C ≥6.5% among diabetic case subjects based on an OGTT. The difference in probability between centers was analyzed by logistic regression adjusting for relevant confounders. RESULTS Diabetes prevalence was lower with the A1C-based diagnostic criteria in four of six studies. The probability of an A1C ≥6.5% among OGTT-diagnosed case subjects ranged widely (17.0–78.0%) by study center. Differences in diagnostic agreement between ethnic subgroups in the U.K. study were of the same magnitude as between-country comparisons. CONCLUSIONS A shift to an A1C-based diagnosis for diabetes will have substantially different consequences for diabetes prevalence across ethnic groups and populations.

OBJECTIVE To examine the recent suggestion that impaired fasting glucose may protect against depression, whereas a diagnosis of diabetes might then result in depression. RESEARCH DESIGN AND METHODS Cross-sectional analysis of 4,228 adults (mean age 60.7 years, 73.0% men) who underwent oral glucose tolerance testing and completed the Center for Epidemiologic Studies Depression scale (CES-D). RESULTS After adjustment for demographic factors, health behaviors, and clinical measurements (BMI, waist circumference, lipid profile, and blood pressure), there was a U-shaped association between fasting glucose and depression (Pcurve = 0.001), with elevated CES-D at low and very high glucose levels. This finding was replicable with 2-h postload glucose (P = 0.11) and A1C (P = 0.007). CONCLUSIONS The U-shaped association between blood glucose and CES-D, with the lowest depression risk seen among those in the normoglycemic range of A1C, did not support the hypothesized protective effect of hyperglycemia.

OBJECTIVE—Interleukin-1 receptor antagonist (IL-1Ra), a natural inhibitor of interleukin-1β, has been shown to improve β-cell function and glycemic control in patients with type 2 diabetes. The aim of this study was to investigate whether baseline systemic levels of IL-1Ra are associated with incident type 2 diabetes during more than 10 years of follow-up. RESEARCH DESIGN AND METHODS—We measured serum IL-1Ra concentrations in a nested case-control study (181 case and 376 age-, sex-, and BMI-matched normoglycemic control subjects) within the Whitehall II cohort (U.K.). RESULTS—IL-1Ra concentrations were higher in case subjects (P = 0.0006) and associated with incident type 2 diabetes (odds ratio for a 1-SD increase of IL-1Ra 1.48 [95% CI 1.21–1.80]). This association remained significant after adjustment for multiple potential confounders but was attenuated by adjusting for 2-h glucose. CONCLUSIONS—Our findings indicate that individuals who will develop type 2 diabetes are characterized by a complex immune activation that also includes upregulation of the anti-inflammatory cytokine IL-1Ra.

OBJECTIVE To assess whether serum anti–heat shock protein 27 (HSP27) antibody levels are associated with micro- and macrovascular complications of type 1 diabetes. RESEARCH DESIGN AND METHODS Anti-HSP27 IgG antibody levels were measured in 531 type 1 diabetic subjects recruited as part of the cross-sectional analysis of the EURODIAB Prospective Complications Study. Case subjects (n = 363) were defined as individuals with one or more diabetes complications and control subjects (n = 168) as individuals with no evidence of any diabetes complication. RESULTS Anti-HSP27 levels were comparable in case and control subjects (19.6 arbitrary units/ml [11.3–32.7] vs. 20.4 arbitrary units/ml [11.7–35.3], geometric mean [interquartile range]), and there was no correlation between HSP27 and anti-HSP27 levels (r = 0.01, P = 0.81). In logistic regression analysis, anti-HSP27 was not associated with the presence of complications, even after adjustment for main risk factors. CONCLUSIONS Anti-HSP27 antibody levels are not a marker of vascular complications in type 1 diabetes.