Non-insulin-dependent Diabetes and 11-Year Mortality in Asian Indian and Melanesian Fijians

Abstract

This study reports 11‐year all‐cause and cause‐specific mortality rates according to baseline glucose tolerance for a population‐based sample of adult Melanesian and Indian Fijians (n = 2638), first surveyed in 1980. Risk factors for all‐cause and cardiovascular disease (CVD) mortality in subjects with non‐insulin‐dependent diabetes (NIDDM) are also described. The baseline survey included 75 g oral glucose tolerance tests, measurements of blood pressure, body mass index, and triceps skinfold, assays of plasma cholesterol and triglycerides, electrocardiograms, and details of smoking habits and physical activity. Mortality status was ascertained for 2546 subjects through surveillance of death certificates, medical records and interview of subjects (or relatives). Mortality rates were increased in diabetic men and women of both ethnic groups: relative risks compared to subjects without diabetes at baseline were 1.7 (CI:0.9–3.1) and 2.0 (1.1–3.7) in Melanesian and 4.2 (2.7–6.5), 3.2 (1.9–5.7) in Indian men and women, respectively. A large proportion of mortality among diabetic subjects was attributed to CVD (62 %, 66 % in Melanesian and 54 %, 58 % in Indian men and women, respectively). Mortality rates tended to be higher in Melanesians than Indians, except for diabetic men where Indians had higher total and cardiovascular disease rates. In contrast to non‐diabetic Fijians, diabetic women of both ethnic groups lost their relative protection from coronary heart disease (CHD). Cox regressions for diabetic subjects showed age and fasting plasma glucose to be independent predictors of all‐cause mortality in men, and age, body mass index (inversely) and systolic blood pressure in women, but lipid concentrations, and cigarette smoking were not related. After accounting for conventional CVD risk factors, diabetes conferred significantly increased risk of total, CVD, and CHD mortality. The mortality experience of Melanesian and Indian Fijians with NIDDM is similar to that documented in developed populations, with excess mortality due to cardiovascular causes.

Diabetes as risk factor for incident coronary heart disease in women compared with men: a systematic review and meta-analysis of 64 cohorts including 858,507 individuals and 28,203 coronary events

“…Dubbo study [42] EPESE [43] Adventist Health Study [39] Reykjavik study [47] Collins et al − Melanesians [41] Kuopio higher in women than in men [37]. Similarly, data from the UK Prospective Diabetes Study indicated that men with newly diagnosed diabetes were significantly less obese compared with newly diagnosed women [35].…”

Ischemic Stroke in South Asians

“…Hypertension, 6 diabetes mellitus, 52,53 dyslipidemia, 54,55 and atrial fibrillation are the most common known risk factors in stroke etiology. The prevalence of these risk factors is known to differ among various ethnic groups 56 and is also associated with manifestations of different stroke subtypes.…”

“…75 However, a direct comparison of Indian migrants to rural contemporaries in villages of origin in India showed no differences in the rates of glucose intolerance. 76 Moreover, despite varied lifestyle approaches, cross-sectional studies from Fiji 6 and Tanzania 8 also question whether urbanization has a role to explain the high prevalence of diabetes among Indian populations. Hence, not only is diabetes more common among South Asians compared with other ethnic groups, 77 but it is likely that this is a hereditable risk factor in this population.…”

“…Cultural and socioeconomic factors may account for part of this excess. Rates of cardiovascular disease (CVD) in Fiji, 6 Singapore, 7 and South Africa 8 are highest among migrant Indians but are largely explained by the excess of coronary heart disease. In the United Kingdom, CVD among South Asian migrants is due to both heart disease and stroke, suggesting that an environmental basis may, in part, underlie the increased risk of stroke in this population.…”

Sex differentials in predictors of mortality for patients with adult-onset diabetes: a population-based follow-up study in Beer-Sheva, Israel.

“…T he increased risk of mortality in diabetic patients compared with that of nondiabetic individuals has been reported in different populations (1)(2)(3)(4)(5)(6)(7)(8). Although some of these studies described sex differences in specific cardiovascular risk factors that may account for differences in cardiovascular mortality (4,6), little attention has been given to the possibility that factors predicting overall mortality could vary between diabetic men and women.…”