Risk Factors for Coronary Heart Disease in a Population with a High Prevalence of Obesity and Diabetes: A Case-Control Study of the Polynesian Population of Western Samoa

Abstract

Objective To evaluate anthropometric, haemodynamic and biochemical risk markers for coronary heart disease (CHD) in the Polynesian population of Western Samoa in a case-control study of 43 cases of CHD compared with 9 0 age-(mean 53 years) and sex-matched controls.Methods Cases were identified on the basis of a 1 2-lead electrocardiogram and clinical history. ResultsMore than 60% of the participants had a body mass index 230 kg/m2 and nearly 80% had central obesity. Both diabetes mellitus (1 7%) and impaired glucose tolerance (9%) were also common in this population. Nineteen per cent of the population were hypertensive and both antihypertensive therapy (21 versus 1%, P<O.OOl, risk 23.6) and hypertension (35 versus 11%, P<O.Ol, risk 4.3) were significantly more common among cases than they were among controls. In addition, the plasma high-density lipoprotein cholesterol level was lower (1.00f0.09 versus 1.24f0.05 mmol/l, P<0.05) and the plasma urate level was higher (0.42 k 0.02 versus 0.37 f 0.0 1 mmol/l, P<0.05) in the female cases than they were in their respective controls. Low-density lipoprotein (LDL) particle sizing did not reveal an excess of small LDL particles to be a feature of CHD cases, but more than 70% both of cases and of controls had multiple LDL species. The response of the triglyceride level to a fat-rich meal was the same for CHD cases and controls. ConclusionThe population studied had a high prevalence of several risk factors for CHD, including obesity and non-insulindependent diabetes mellitus; however, the most prominent factor relating to CHD within the community was the presence of hypertension. In trod uctionStudies in economically developed countries have consistently identified hypertension, cigarette smoking, diabetes mellitus, specifically non-insulin dependent diabetes mellitus and hypercholesterolaemia as independent major risk factors for coronary heart disease (CHD). Pacific island populations, such as the Polynesian population of Western Samoa, are known to have a high and rising prevalence of many of these risk factors as well as of obesity [l]. Obesity is less well established as an independent risk factor, but may be operative through associations with hyperinsulinaemia, fasting and post-prandial hypertriglyceridaemia, a low high-density-lipoprotein (HDL) cholesterol level and the presence of small, dense low-density lipoprotein (LDL) particles [2,3]. No information is available on the relative importance, within this population, of the classical risk factors as well as of those factors, such as the presence of small dense L D L particles and exaggerated post-prandial hypertriglyceridaemia, that are likely to affect an obese population with an increasing prevalence of noninsulin-dependent diabetes mellitus [4,5].We report here the findings of such a study, in which we determined the prevalences of several risk factors among cases with C H D and age-and sex-matched controls. In addition to possible differences in the prevalence of diabetes, hypertension and hypercholesterolaem...

Low-density lipoprotein particle number and risk for cardiovascular disease

“…To date, 17 cross-sectional epidemiologic [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27], eight prospective epidemiologic [28-33,34••,35], and six clinical intervention trials [36][37][38][39][40][41] have examined the relationship of LDL particle size and CHD risk. Of the 17 cross-sectional studies reviewed, 12 demonstrated a significant univariate relationship between small-sized LDL particles and CHD [12][13][14][15][16][17][18][24][25][26][27], whereas two trials [19,20] reported an association of large-sized LDL particles with CHD.…”

Low-Density Lipoprotein Size, Pravastatin Treatment, and Coronary Events

“…15,16 Predominance of small LDL in patients with coronary disease may simply reflect these other traits, and so its clinical utility has been questioned. 16,17 Indeed, in studies in which triglyceride concentrations were similar in cases and controls, small LDL was either unrelated 9,10,14 or inversely related 7,8 with risk of coronary disease. Because of such strong confounding, the true direct relationship, if any, between LDL size and coronary disease has been difficult to determine.…”

Self‐Reported Body Mass Index and Health‐Related Quality of Life: Findings from the Behavioral Risk Factor Surveillance System

“…Although more recent studies have resulted in renewed attention to the relationship between quality of life and being overweight (6, 7, 8, 9, 10, 11, 12, 13), this research has generally been limited to special populations or to studies conducted outside the United States. Because the prevalence of overweight and obesity varies widely across cultures (14, 15, 16) and because the impact of obesity may, in part, be culturally determined, we used data from the 1996 Behavioral Risk Factor Surveillance Survey (BRFSS) to examine the association between health‐related quality of life and self‐reported body mass index (BMI) in a large sample of U.S. adults. We explored this relationship across age groups, among men and women, and among different racial or ethnic groups in the United States.…”