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OBJECTIVE To empirically derive dietary patterns and examine their association with incident type 2 diabetes. RESEARCH DESIGN AND METHODS We used data from the Singapore Chinese Health Study, including 43,176 Chinese men and women (aged 45–74 years), free of diabetes, cardiovascular disease, and cancer at baseline (1993–1998) and followed up through 2004. Two major dietary patterns were identified using principal components analysis: a vegetable, fruit, and soy-rich pattern (VFS) and a dim sum and meat-rich pattern (DSM). Pattern scores for each participant were calculated and examined with type 2 diabetes risk using Cox regression. RESULTS The associations of the two dietary patterns with diabetes risk were modified by smoking status. Neither pattern was associated with risk of diabetes in ever smokers. In never smokers, the VFS dietary pattern was inversely associated with risk of type 2 diabetes. Compared with the lowest quintile of the VFS dietary pattern score, the hazard ratios (HRs) for quintiles 2–5 were 0.91, 0.82, 0.73, and 0.75 (P = 0.0005 for trend). The DSM dietary pattern was positively associated with risk of type 2 diabetes in never smokers, with HRs for quintiles 2–5 of 1.07, 1.25, 1.18, and 1.47 (P < 0.0001 for trend). CONCLUSIONS A dietary pattern with higher intake of vegetables, fruits, and soy foods was inversely associated with risk of incident type 2 diabetes, and a pattern with higher intake of dim sum, meat and processed meat, sweetened foods and beverages, and fried foods was associated with a significantly increased risk of type 2 diabetes in Chinese men and women in Singapore.

OBJECTIVE Glycated hemoglobin (HbA1c) is a robust biomarker of the preceding 2 to 3 months average blood glucose level. The aim of this study was to examine the association between HbA1c and mortality in a cohort of Southeast Asians. RESEARCH DESIGN AND METHODS Analysis of 7,388 men and women, mean age 62 years, from the Singapore Chinese Health Study who provided a blood sample at the follow-up I visit (1999–2004) and reported no history of diabetes, previous adverse cardiovascular events, or cancer. A total of 888 deaths were identified through 31 December 2011 via registry linkage. Participants represented a random study sample of potential control subjects for a nested case-control genome-wide association study of type 2 diabetes in the population. Hazard ratios (HRs) for all-cause and cause-specific mortality by six categories of HbA1c were estimated with Cox regression models. RESULTS Relative to participants with an HbA1c of 5.4–5.6% (36–38 mmol/mol), participants with HbA1c ≥6.5% (≥48 mmol/mol) had an increased risk of all-cause, cardiovascular, and cancer mortality during an average of 10.1 years of follow-up; HRs (95% CIs) were 1.96 (1.56–2.46), 2.63 (1.77–3.90), and 1.51 (1.04–2.18), respectively. No level of HbA1c was associated with increased risk of respiratory mortality. Levels CONCLUSIONS HbA1c levels consistent with undiagnosed type 2 diabetes (≥6.5%) are associated with an increased risk of all-cause and cause-specific mortality in Chinese men and women.

OBJECTIVE Increased BMI is a robust risk factor for type 2 diabetes. Paradoxically, South Asians have relatively low BMIs despite their high prevalence of type 2 diabetes. We examined the association between BMI and incident type 2 diabetes because detailed prospective cohort data on this topic in Asians are scarce. RESEARCH DESIGN AND METHODS This study was a prospective analysis of 37,091 men and women aged 45–74 years in the Singapore Chinese Health Study, using Cox regression analysis. RESULTS Risk of incident type 2 diabetes significantly increased beginning with BMIs 18.5–23.0 kg/m2(relative risk 2.47 [95% CI 1.75–3.48]) and continued in a monotonic fashion across the spectrum of BMI. Results were stronger for younger than for older adults. CONCLUSIONS BMIs considered lean and normal in Singaporean Chinese are strongly associated with increased risk of incident type 2 diabetes. This association weakened with advanced age but remained significant.

OBJECTIVE The objective of this study was to determine potential added value of novel risk factors in predicting the development of type 2 diabetes beyond that provided by standard clinical risk factors. RESEARCH DESIGN AND METHODS The Atherosclerosis Risk in Communities (ARIC) Study is a population-based prospective cohort study in four U.S. communities. Novel risk factors were either measured in the full cohort or in a case-control sample nested within the cohort. We started with a basic prediction model, previously validated in ARIC, and evaluated 35 novel risk factors by adding them independently to the basic model. The area under the curve (AUC), net reclassification index (NRI), and integrated discrimination index (IDI) were calculated to determine if each of the novel risk factors improved risk prediction. RESULTS There were 1,457 incident cases of diabetes with a mean of >7.6 years of follow-up among 12,277 participants at risk. None of the novel risk factors significantly improved the AUC. Forced expiratory volume in 1 s was the only novel risk factor that resulted in a significant NRI (0.54%; 95% CI: 0.33–0.86%). Adiponectin, leptin, γ-glutamyl transferase, ferritin, intercellular adhesion molecule 1, complement C3, white blood cell count, albumin, activated partial thromboplastin time, factor VIII, magnesium, hip circumference, heart rate, and a genetic risk score each significantly improved the IDI, but net changes were small. CONCLUSIONS Evaluation of a large panel of novel risk factors for type 2 diabetes indicated only small improvements in risk prediction, which are unlikely to meaningfully alter clinical risk reclassification or discrimination strategies.

OBJECTIVE—Physical activity and insulin sensitivity are related in epidemiological studies, but the consistency of this finding among populations that greatly differ in body size is uncertain. The present multiethnic epidemiological study examined whether physical activity was related to insulin concentrations in two populations at high risk for diabetes that greatly differ by location, ethnic group, and BMI. RESEARCH DESIGN AND METHODS—The study populations consisted of 2,321 nondiabetic Pima Indian men and women aged 15–59 years from Arizona and 2,716 nondiabetic men and women aged 35–54 years from Mauritius. Insulin sensitivity was estimated by mean insulin concentration (average of the fasting and postload insulin), and total (i.e., leisure and occupational) physical activity was assessed by questionnaire. RESULTS—Pima men and women who were more active had significantly (P < 0.05) lower mean insulin concentrations than those less active (BMI and age-adjusted means were 179 vs. 200 and 237 vs. 268 pmol/l). Similar findings were noted in Mauritian men and women (94 vs. 122 and 127 vs. 148 pmol/l). In both populations, activity remained significantly associated with mean insulin concentration controlled for age, BMI, waist-to-thigh or waist-to-hip ratio, and mean glucose concentrations. CONCLUSIONS—Physical activity was negatively associated with insulin concentrations both in the Pima Indians, who tend to be overweight, and in Mauritians, who are leaner. These findings suggest a beneficial role of activity on insulin sensitivity that is separate from any influence of activity on body composition.