OBJECTIVE:To investigate the association between circulating C-reactive protein (CRP) concentrations and indices of body fat distribution and the insulin resistance syndrome in South Asians and Europeans. DESIGN: Cross-sectional study. SUBJECTS: A total of 113 healthy South Asian and European men and women in West London (age 40 -55 y, body mass index (BMI) 17 -34 kg=m 2 ). MEASUREMENTS: Fatness and fat distribution parameters (by anthropometry, dual-energy X-ray absorptiometry and abdominal CT scan); oral glucose tolerance test with insulin response; modified fat tolerance test; and CRP concentration by sensitive ELISA. RESULTS: Median CRP level in South Asian women was nearly double that in European women (1.35 vs 0.70 mg=1, P ¼ 0.05). Measures of obesity and CRP concentration were significantly associated in both ethnic groups. The correlation to CRP was especially strong among South Asians (P<0.01) for measures of central obesity (waist girth and visceral fat area), whereas BMI and percentage fat were more significantly associated with CRP in Europeans (P<0.05). In South Asians the associations of CRP with visceral fat area and waist girth persisted after adjustment for either BMI or percent fat (all, P<0.05). In age-, sex-and smoking-adjusted regression analyses CRP concentrations were significantly associated with fasting and 2 h insulin and lipid levels in both ethnic groups (P<0.05). When further statistical adjustment was made for visceral fat area these associations were abolished (P >0.15). CONCLUSION: We suggest that adiposity and in particular visceral adipose tissue is a key promoter of low-grade chronic inflammation. This observation may in part account for the association of CRP with markers of the metabolic syndrome. Future studies should confirm whether CRP concentrations are elevated in South Asians and whether losing weight by exercise or diet, or reduction in visceral fat mass, is associated with reduction in plasma CRP concentrations.

Resistance to insulin-mediated glucose uptake has been implicated in the pathogenesis of Type II (non±insulin-dependent) diabetes mellitus, hypertension and coronary heart disease [1]. Insulin resistance is present in several non-European ethnic groups in which prevalence of' Type II diabetes is higher than in Europeans matched with them for weight, for instance in people of South Asian (Indian, Pakistani, Bangladeshi and Sri Lankan) descent [2]. Insulin resistance is strongly associated with obesity, especially central obesity, but the mechanism of this association is poorly understood. One possibility is that non-esterified fatty acids (NEFA) produced by lipolysis of triglyceride stores in muscle cells block glucose uptake either through substrate competition, as proposed over 30 years ago [3], or through direct inhibition of glucose transport [4].The relation of insulin sensitivity to intramyocellular lipid (IMCL) has been examined in muscle biopsy Diabetologia (1999) AbstractAims/hypothesis. To compare the relation between intramyocellular lipid content, central obesity and insulin sensitivity in Europeans and South Asians. Methods. Cross-sectional study of 40 South Asian and European non-diabetic men matched for age and body mass index. We measured intramyocellular lipid by proton magnetic resonance spectroscopy of soleus muscle, insulin sensitivity by the short insulin tolerance test, per cent body fat by dual-energy x-ray absorptiometry and visceral fat by single-slice computed tomography of the abdomen. Results. South Asians compared with Europeans had a higher mean per cent body fat (26.8 % vs 22.5 %, p = 0.05) and lower insulin sensitivity (mean ± SEM 2.4 ± 0.2 vs 3.4 %/min ± 0.3, p = 0.013). Mean ( ± SEM) intramyocellular lipid content was higher in South Asians than in Europeans (72.1 ± 7.5 vs 53.6 ± 4.9 mmol/kg dry weight, p = 0.046). In Europeans intramyocellular lipid was correlated with per cent body fat (r = 0.50, p = 0.028), waist:hip ratio (r = 0.74, p < 0.001), visceral fat (r = 0.62, p = 0.004) and insulin sensitivity (r = ±0.53, p = 0.016). In South Asians intramyocellular lipid was not significantly related to insulin sensitivity or obesity, and the strongest associations of insulin sensitivity were with fasting plasma triglyceride and waist:hip ratio. Conclusion/interpretation. The association of intramyocellular lipid with insulin sensitivity and obesity in Europeans is consistent with the hypothesis that muscle triglyceride mediates the effect of obesity on insulin sensitivity. The absence of a similar relation of insulin sensitivity to intramyocellular lipid in South Asians suggests that other mechanisms underlie the high insulin resistance observed in this group. [Diabetologia (1999) 42: 932±935]

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OBJECTIVE: To investigate correlates of body mass index (BMI) and other anthropometric measurements in South Asian, Afro-Caribbean and European women in the UK. SUBJECTS: 291 South Asian, 303 Afro-Caribbean, and 559 European women aged 40 ± 69 y in West London, UK. DESIGN: Cross-sectional survey. MAIN OUTCOME MEASURES: BMI, waist-to-height ratio (WHt), and skinfold thicknesses. RESULTS: Compared with European women, South Asian and Afro-Caribbean women were more like to be obese (odds ratios (OR) 1.83 and 3.01, respectively), but less likely to rate themselves as overweight (BMI-adjusted OR 0.19 and 0.34, respectively). The proportion of women who walked at least 2.5 kmad, excluding activity at work, was lower in South Asians (22%) than in Europeans (44%) or Afro-Caribbeans (40%). Among employed women, the proportion who were active at work was higher in South Asians (63%) and Afro-Caribbeans (70%) than in Europeans (49%). In Europeans, obesity was inversely associated with social class, education, smoking, alcohol intake, and distance walked, and positively associated with time spent watching television. Adjustment for alcohol intake, smoking, education and transport, physical activity explained over 80% of the difference in BMI between South Asians and Europeans, but not the difference between Afro-Caribbeans and Europeans. CONCLUSION: The factor that may be most amenable to intervention in South Asian women is low physical activity outside the workplace. The high prevalence of obesity in Afro-Caribbean women, however, is not accounted for by any behavioural factors measured in this study, and the reasons for high rates of obesity in this group remain to be established.

The prevalence of hypertension is particularly high in people of black African descent throughout the world, and the consequences of hypertension, such as hypertensive heart and renal disease and stroke, are also more common. But there is little consensus on whether hypertensive retinopathy follows a similar pattern. We determined the prevalence of hypertensive retinopathy and its relationships with resting and ambulatory blood pressure in a population study of Afro-Caribbeans and Europeans aged 40 to 64 years in London, UK. Retinal photographs of 651 participants were graded for hypertensive retinopathy. Age- and sex-standardized prevalence of retinopathy was 11% (95% confidence interval, 8% to 14%) in Europeans and 21% (95% confidence interval, 16% to 26%) in Afro-Caribbeans (P < .001), respectively. This ethnic difference in prevalence was greatest in normotensive women (8% in Europeans versus 20% in Afro-Caribbeans, P < .001). Resting systolic pressure was 8 mm Hg higher in normotensive Afro-Carribean compared with European women, but this could not fully account for the ethnic difference in the prevalence of retinopathy. Examination of the different relationships of age and resting and ambulatory blood pressures with hypertensive retinopathy showed that these relationships were strongest in European women and weakest in Afro-Caribbean women. We conclude that hypertensive retinopathy is more common in Afro-Caribbeans, particularly women, and that ethnic differences in resting blood pressure cannot fully account for this. The relatively weak relationship between resting and ambulatory blood pressures and retinopathy in Afro-Caribbeans suggests that factors other than blood pressure determine the high rates of hypertensive retinopathy in this group.