Nishi Chaturvedi

Resting and ambulatory blood pressure differences in Afro-Caribbeans and Europeans.

To investigate why mortality from stroke in people of Afro-Caribbean origin is twice the average for England and Wales, we examined 1166 European and Afro-Caribbean people in London. Age-standardized median systolic blood pressure was 6 mm Hg higher (128 versus 122 mm Hg) in Afro-Caribbean than European men and 17 mm Hg higher (135 versus 118 mm Hg) in Afro-Caribbean than European women. Migrants from West Africa and the Caribbean had similar blood pressures. Body mass index was higher in Afro-Caribbean than European women, accounting for 4 mm Hg of the systolic difference. Diabetes prevalence was 16% in Afro-Caribbeans and 5% in Europeans (P < .001), accounting for 1 mm Hg of the difference in systolic pressure in men and 2 mm Hg in women. In participants not taking antihypertensive medication, mean fall in ambulatory systolic pressure between daytime and nighttime, adjusted for resting blood pressures, was 24 mm Hg in Europeans and 18 mm Hg in Afro-Caribbeans (P = .05), and percent day-night fall in systolic blood pressure adjusted for resting systolic pressure was 17% in Europeans and 12% in Afro-Caribbeans (P < .05). This difference persisted when men and women and normotensive and hypertensive individuals were examined separately. We estimate that the differences in blood pressure between Afro-Caribbeans and Europeans may be enough to account for ethnic differences in stroke mortality in women but not men. The reasons for the high prevalence of hypertension and related morbidity in this and other populations of African descent remain to be established.

Mortality and morbidity from diabetes in South Asians and Europeans : 11-year follow-up of the southall diabetes survey, London, UK

Over 20 % of middle aged and elderly South Asian people throughout the world have diabetes. The associated mortality and morbidity risks are unclear. We compared mortality and morbidity in a cohort of South Asian and European people with diabetes in London, UK, in an 11‐year follow‐up of a population‐based sample of 730 South Asians (mean age 55 in 1984) and 304 Europeans (mean age 67 in 1984) with diabetes aged 30 years and above in 1984. By 1995, 242 (33 %) of South Asians, and 172 (57 %) of Europeans had died. The all‐cause mortality rate ratio (South Asian versus European) was 1.50 (95 % CI 0.72–3.12) for those aged 30–54 years at baseline. Ethnic differences in mortality rates were abolished or reversed in people aged 65 years and above at baseline. The mortality rate ratio for circulatory deaths was 1.80 (95 % CI 1.03–3.16, p < 0.05) and for heart disease was 2.02 (95 % CI 1.04–3.92, p < 0.05) in those aged 30–64 years at baseline. Seventy‐seven per cent of South Asian deaths were caused by circulatory disease, compared with 46 % of European deaths. South Asian survivors were 3.8 times (95 % CI 1.8–8.0, p = 0.001) more likely to report a history of myocardial infarction than Europeans. South Asian adults with diabetes show a markedly increased predisposition to cardiovascular disease compared with Europeans, especially in younger people. This emphasizes the urgent need to reduce cardiovascular risk in this vulnerable group.

The Relationship Between Smoking and Microvascular Complications in the EURODIAB IDDM Complications Study

OBJECTIVE To examine the relationship between smoking and both glycemic control and microvascular complications in patients with insulin-dependent diabetes mellitus (IDDM). RESEARCH DESIGN AND METHODS This was a prevalence survey of 3,250 men and women aged 15–60 years with IDDM from 31 diabetes centers in 16 European countries. Participants completed a questionnaire, had retinal photographs taken, and performed a 24-h urine collection. HbA1c, frequency of hypoglycemic and ketoacidotic episodes, urinary albumin excretion rates, and retinopathy were compared by smoking category. RESULTS The prevalence of smoking was 35% in men and 29% in women. Current smokers had poorer glycemic control and, among men, were more likely to have had a ketoacidotic episode than were those who never smoked. Ex-smokers had equivalent glycemic control and marginally more hypoglycemic episodes did than those who never smoked. Current smokers had a higher prevalence of microalbuminuria and total retinopathy than did those who never smoked. Ex-smokers had a higher prevalence of macroalbuminuria and proliferative retinopathy than did those who never smoked, but both had a similar prevalence of microalbuminuria. Adjustment for either current or long-term glycemic control could not fully account for these differences. CONCLUSIONS Smoking is associated with poorer glycemic control and an increased prevalence of microvascular complications compared with not smoking. Ex-smokers can achieve glycemic control equivalent to and have a prevalence of early complications similar to that of those who never smoked. We suggest that poorer glycemic control can account for some of the increased risk of complications in smokers, and that quitting smoking would be effective in reducing the incidence of complications. Urgent action is required to reduce the high smoking rates in people with IDDM.

Risk factors, ethnic differences and mortality associated with lower-extremity gangrene and amputation in diabetes. The WHO Multinational Study of Vascular Disease in Diabetes.

Abstract.Aims/hypothesis: We aimed to examine geographic differences, risk factors and mortality associated with amputation. Methods: Data from 10 of the original 14 centres of the WHO Multinational Study of Vascular Disease in Diabetes were used. This included 3443 men and women aged 35 to 55 years at baseline. Results: Incidences of amputation, adjusted for sex and duration in Type I (insulin-dependent) diabetes mellitus, were 31.0, 8.2, 3.5 and 1.0 per 1000 person years in the American Indian, Cuban, European and East Asian centres respectively. In Type II (non-insulin-dependent) diabetes mellitus, incidences of amputation were 9.7, 2.0, 2.5 and 0.7 per 1000 person years in the American Indian, Cuban, European and East Asian centres respectively. Key risk factors for amputation included glucose, triglyceride, and retinopathy, and were similar for American Indians and Europeans. The age, duration and sex adjusted relative risk for amputation in American Indians compared with Europeans was 11.48 (95 % CI 3.56, 36.98) in Type I diabetes and 3.86 (95 % CI 2.36, 6.32) in Type II diabetes. Adjusting for heart disease, retinopathy, proteinuria, glucose, blood pressure and triglyceride attenuated these relative risks to 10.83 (95 % CI 3.20, 36.65) and 3.15 (1.91, 5.20) in Type I and Type II diabetes respectively. Amputation doubled mortality rates in all groups. Conclusion/interpretation: Vascular complications and their risk factors are themselves risk factors for amputation in both Type I and Type II diabetes and are common to several geographical regions worldwide. However, reasons for differences between geographical regions and the degree to which different health care systems could be responsible is not clear. [Diabetologia (2001) 44 [Suppl 2]: S 65–S 71]

Comparison of prevalence and risk factors for microalbuminuria in South Asians and Europeans with Type 2 diabetes mellitus

Although Type 2 (non‐insulin‐dependent) diabetes mellitus (Type 2 DM) is more common in South Asians than in Europeans in the UK, very little is known about complications and their risk factors in South Asians. We sought microalbuminuria in a cross‐sectional study of 583 European and 889 South Asian Type 2 DM clinic attenders to Ealing Hospital, London, over 1 year. Albumin/creatinine ratios were measured in early morning urines. Prevalence of microalbuminuria was greater in South Asians compared to Europeans (40 % versus 33 % in men, p = 0.003, and 33 % versus 19 % in women, p < 0.0001). Glycaemic control was worse and prevalence of hypertension, retinopathy and heart disease was higher in South Asians. Key risk factors for microalbuminuria in both ethnic groups were glycaemic control, diabetes duration, blood pressure, triglyceride and retinopathy, but none accounted for the higher microalbuminuria prevalence in South Asians. Age and sex adjusted odds ratio for microalbuminuria was 1.78 (95 % CI 1.02, 2.82, p = 0.02) in South Asians versus Europeans. After adjustment for confounders, this became 2.07, 95 % CI 1.13, 3.79, p = 0.02. We conclude that microalbuminuria is more common in South Asians with Type 2 DM than in Europeans and, although risk factor relationships appeared similar in both groups, and some risk factors were more prominent in South Asians, this cannot account for the high prevalence of microalbuminuria observed in South Asians.

The Relationship Between Socioeconomic Status and Diabetes Control and Complications in the EURODIAB IDDM Complications Study

OBJECTIVE To determine whether there are socioeconomic differences in diabetes control and complications in people with IDDM. RESEARCH DESIGN AND METHODS We conducted a prevalence survey of 1,217 men and 1,170 women with IDDM age 25–60 years from European clinics. Age at completion of education defined socioeconomic status: ≤ 14 years defined those with primary education; 15–18 years, as secondary education; and > 19 years, as college education. Glycemic control, lipids, diet, retinopathy, neuropathy, and heart disease were assessed centrally. RESULTS People with a primary education were older and had diabetes for longer than those with a college education. The mean percentage of HbA1c was worst in the primary-educated men (6.6 vs. 6.1%, P = 0.0007 for trend) and women (6.5 vs. 6.0%, P = 0.0007). Total cholesterol level was higher in primary-educated than in college-educated men (5.6 vs 5.3 mmol/l, P = 0.002), as was triglyceride level (1.23 vs. 1.02 mmol/l, P = 0.0001). College-educated people were the least likely to be current smokers (P < 0.0001), and were most likely to partake in vigorous exercise (P < 0.001). Surprisingly, There was little difference in the prevalence of heart disease by educational status in men, while it was highest in the least educated women, but proliferative retinopathy was more common in primary- than in college-educated men (16 vs 10%, P = 0.04) as was macroalbuminuria (15 vs 9%, P = 0.03). Glycemic control could not fully account for these differences. CONCLUSIONS Healthy lifestyles are more prevalent in better educated men and women with IDDM, but these are not reflected in heart disease prevalence in men. The lower prevalence of severe microvascular complications in better educated men, unaccounted for by better glycemic control, requires further investigation.

Autonomic neuropathy is associated with increased cardiovascular risk factors: the EURODIAB IDDM Complications Study.

Aims To assess the prevalence of and risk factors for autonomic neuropathy in the EURODIAB IDDM Complications Study.

Methods for epidemiological surveys of ethnic minority groups.

OBJECTIVE--Research into the health of minority ethnic groups is often restricted by methodological difficulties. These include the lack of accurate population denominators, the choice of an appropriate sampling frame, correctly assigning ethnic group, and biases in techniques used for sampling and investigation. This article reviews the available sources or mortality and morbidity data, and assesses their uses and limitations for research involving ethnic minority groups. Suitable sampling frames and review methods used to assign ethnicity are discussed. Sources of bias are high-lighted and methods used to overcome these biases are presented. CRITERIA FOR INCLUSION OF ARTICLES--Articles have been chosen which best illustrate the problems encountered and show how these problems can be addressed. CONCLUSIONS--The increased documentation of ethnic origin on routine data sources is welcomed, but attention must be paid to ensuring that congruent definitions in data collection are used. The worrying consequences of the Commission of European Communities directive, which describes the need for explicit consent to be obtained from subjects before data is used for anything other than its original purpose, are discussed.

ECHOCARDIOGRAPHIC MEASURES OF LEFT-VENTRICULAR STRUCTURE AND THEIR RELATION WITH REST AND AMBULATORY BLOOD-PRESSURE IN BLACKS AND WHITES IN THE UNITED-KINGDOM

OBJECTIVES This study attempted to determine whether people of black African descent have more left ventricular hypertrophy than those of white European descent and whether this can be explained by rest or ambulatory blood pressure. BACKGROUND Mortality associated with hypertension is higher in black populations than among whites, but differences in morbidity and their associations with blood pressure are inconsistent. METHODS We examined 1,166 black and white men and women 40 to 64 years old in a community survey in London, United Kingdom. Echocardiograms were obtained for all subjects and ambulatory blood pressure recordings for 319. RESULTS Adjusted for body size, ventricular septal thickness was greater in blacks than whites (p < 0.05), and cavity dimension was smaller (p < 0.05). In men, ventricular septal thickness was > 10 mm for 32% of whites and 53% of blacks; for women these figures were 14% and 38%, respectively. Relative wall thickness was greater in blacks (p < 0.01 for men and women), but left ventricular mass index was similar in the two ethnic groups. In men, hypertension resulted in an increase in wall thickness in both ethnic groups, but cavity dimension decreased in blacks and increased in whites. Wall thickness was higher in blacks than in whites for equivalent levels of either rest (p = 0.05) or ambulatory (p = 0.007) blood pressure. CONCLUSIONS Left ventricular mass index may not be valid for comparison between ethnic groups because this derived measure does not take into account ethnic differences in ventricular structural response to hypertension. Interventricular wall thickness may be more valid. Using this measure, we demonstrate greater ventricular hypertrophy in blacks than in whites, unexplained by differences in either rest or ambulatory blood pressure. The pattern of ventricular hypertrophy observed in blacks is associated with an increased mortality risk. Conventional blood pressure thresholds for instituting antihypertensive treatment may be too conservative for people of black African descent.

Risk factors for non-fatal myocardial infarction in young South Asian adults

Objective: To determine the risk factors for premature myocardial infarction among young South Asians. Design and setting: Case–control study in a hospital admitting unselected patients with non-fatal acute myocardial infarction. Methods and subjects: Risk factor assessment was done in 193 subjects aged 15–45 years with a first acute myocardial infarct, and in 193 age, sex, and neighbourhood matched population based controls. Results: The mean (SD) age of the subjects was 39 (4.9) years and 326 (84.5%) were male. Current smoking (odds ratio (OR) 3.82, 95% confidence interval (CI) 1.47 to 9.94), use of ghee (hydrogenated vegetable oil) in cooking (OR 3.91, 95% CI 1.52 to 10.03), raised fasting blood glucose (OR 3.32, 95% CI 1.21 to 8.62), raised serum cholesterol (OR 1.67, 95% CI 1.14 to 2.45 for each 1.0 mmol/l increase), low income (OR 5.05, 95% CI 1.71 to 14.96), paternal history of cardiovascular disease (OR 4.84, 95% CI 1.42 to 16.53), and parental consanguinity (OR 3.80, 95% CI 1.13 to 1.75) were all independent risk factors for acute myocardial infarction in young adults. Formal education versus no education had an independently protective effect on acute myocardial infarction (OR 0.04, 95% CI 0.01 to 0.35). Conclusions: Tobacco use, ghee intake, raised fasting glucose, high cholesterol, paternal history of cardiovascular disease, low income, and low level of education are associated with premature acute myocardial infarction in South Asians. The association of parental consanguinity with acute myocardial infarction is reported for the first time and deserves further study.