S.P.B. Donnan

The prevalence of diabetes mellitus and impaired glucose tolerance among Hong Kong Chinese adults of working age

We studied 1513 employees (910 men and 603 women) from a public utility company and a regional hospital to document the prevalence of diabetes mellitus (DM) and impaired glucose tolerance (IGT) in the Chinese working population of Hong Kong using a 75-g oral glucose tolerance test and World Health Organisation (1985) criteria. The overall prevalence of DM was 4.5 (95% confidence interval: 3.5-5.7%) and that of IGT 7.3 (6.0-8.6%). The prevalence of DM was 5.1 (3.7-6.5%) in men and 3.6 (2.1-5.1%) in women, while that of IGT was 7.4 (5.7-6.5%) in men and 7.1 (5.1-9.1%) in women. The truncated age-adjusted rate of DM for age 30-64 is 7.7% which is comparable to the age-adjusted prevalence rates among Chinese living in Singapore and Mauritius but in marked contrast to the low prevalence rate in Chinese living in Mainland China. Among the diabetic subjects, 38.2% had been previously diagnosed and 32% gave a family history affecting at least one first degree relative. Using polychotomous logistic regression analysis, the independent predictive factors for the development of DM include age (t = 7.31, P < 0.001), family history (t = 5.1, P < 0.001), waist hip ratio (t = 4.05, P < 0.001) and body mass index (t = 4.62, P < 0.001). Our data further confirm that Hong Kong Chinese have a moderate to high susceptibility to non-insulin-dependent diabetes (NIDDM) when exposed to sufficient environmental and lifestyle factors. The high prevalence of IGT indicates a potential for the prevalence of DM to continue to rise unless effective preventive measures are implemented.

Epidemiology of coronary arterial disease in the Chinese

The occurrence of coronary arterial disease and, in particular, acute myocardial infarction in three Chinese communities, namely Hong Kong, Taiwan and China, was reviewed by using a multifaceted approach. Both the prevalence and death incidence of coronary arterial disease or acute myocardial infarction were much lower than those in most western countries: in these three places, the prevalence of coronary arterial disease, the incidence of mortality from coronary arterial disease, the incidence of acute myocardial infarction and the mortality from acute myocardial infarction were roughly one-eighth to one-quarter of the average western figures. While the prevalence and mortality figures have been declining in most affluent western countries, they have been increasing in these three large Chinese communities with 1200 million people. The implication of this increasing trend should certainly deserve more consideration in future planning in these regions. While aging is a contributing factor to such a trend, more work is required to delineate and assess the relative significance of the changes in the socioeconomic and coronary risk factors in the process of modernisation.

Risk factors for acute myocardial infarction in a Southern Chinese population

Although the mortality rate from coronary artery disease in Hong Kong is only one-fourth of that of northern Europe and the United States, the disease has been and remains the second major cause of death (after all cancers combined). Beginning in 1987, we have conducted a case-control study of acute myocardial infarction in four Hong Kong hospitals. This study, one of the biggest case-control studies conducted in the Chinese population of both men and women, confirms the importance of several risk factors--cigarette smoking, history of hypertension, history of diabetes, body fatness, and lack of physical activity--previously described in data collected in western populations. In addition, more adverse childhood experience was also found to be an important risk factor of acute myocardial infarction. Further research in appropriate intervention measures in education in the prevention and cessation of smoking, the control of blood pressure, diabetes, and overweight, and adequate exercise could significantly help reduce the risk of acute myocardial infarction in the Hong Kong Chinese population.

Serum lipid profile and its association with some cardiovascular risk factors in an urban chinese population

&NA; The lipid profile of a Chinese population, which has a lower prevalence of coronary heart disease compared with Caucasians, is studied to determine whether lipid‐modifying disease prevention programs are necessary. The study population consisted of 910 men (mean age 36.7 ± 9.2 yrs) and 603 women (mean age 38.6 ± 9.1 yrs), who were employees of a public utility company and non‐medical staff of a district hospital. Indices of obesity, fasting cholesterol (TC), and its various subfraction, triglycerides (TG), apolipoprotein A‐1 (Apo A‐1), and apolipoprotein B (Apo B) concentrations were measured. Glucose tolerance was also estimated by measuring fasting and 2 h glucose after a 75 g oral glucose load. The lipid profile was similar to that of the North American population, with an overall prevalence of low density lipoprotein cholesterol (LDL‐C) ≥ 4.1 mmol/L of 21% and 11% in men and women respectively. Similar variations with age, sex, smoking and glucose tolerance compared with Caucasian populations were observed. The high prevalence of subjects with “undesirable” lipid values in this Chinese population, which at present has a coronary artery disease prevalence of one‐eighth to one‐quarter compared with that in Caucasians, suggests that the incidence of the disease may well rise in the future to pose a similar problem to that in Caucasian populations. Cut off values of lipids conferring increased cardiovascular risks need to be determined in this population, so that public health strategies may be formulated.

Plasma 25-Hydroxyvitamin D Concentration in Patients with Hip Fracture in Hong Kong

The serum concentration of 25-hydroxyvitamin D level and plasma albumin-adjusted calcium, phosphate, and alkaline phosphatase levels were studied in 200 patients with hip fracture (age range 49-93 years) and 427 elderly subjects living in the community (age range 60-90 years). The mean serum 25-hydroxyvitamin D levels in controls were higher than in temperate countries, but the 25-hydroxyvitamin D concentration was significantly lower in the patients than the controls for all sex and age groups. There was little difference in albumin-adjusted calcium and alkaline phosphatase levels, but the phosphate level was higher in the patients than in the controls. None of the patients with a low 25-hydroxyvitamin D level had a blood picture suggestive of osteopathy resulting from vitamin D deficiency or frank osteomalacia. Hip fracture patients with a low 25-hydroxyvitamin D level were much less ambulant and went outdoors much less frequently than hip fracture patients with a normal vitamin D level. A low vitamin D level was a risk factor for hip fracture in Hong Kong Chinese, and may be prevented by frequent outdoor exposure.

Nutritional status of healthy, active, Chinese elderly

1. Anthropometric indices are presented for 402 healthy Chinese elderly subjects leading an active life in the community in Hong Kong. 2. Women had higher body-mass index (weight/height) and body fat, while fat-free mass, arm-muscle circumference and corrected arm-muscle area were higher in men. Body-mass index, fat-free mass, arm-muscle circumference and corrected arm-muscle area did not decline with age. Total body fat was lower in women aged 75 years and above compared with those aged 60-64 years. 3. All values were lower than those for elderly Caucasians. A different criteria for severe wasting malnutrition among elderly Chinese should be established.

Lipids, lipoproteins and other coronary risk factors in Chinese male survivors of myocardial infarction

OBJECTIVE To assess the importance of an abnormal lipid profile as a risk factor in relation to non-biochemical risk factors, and to define the risk levels for lipid, lipoprotein and apolipoprotein in a Chinese population. PATIENTS AND METHODS Serum lipids, lipoproteins, apolipoproteins and other cardiovascular risk factors were studied in 89 Chinese men 3 months after acute myocardial infarction and 56 controls. RESULTS Cases had higher mean total cholesterol (TC), LDL- and VLDL-cholesterol, triglycerides and apolipoprotein B (Apo B), and lower mean HDL-cholesterol and apolipoprotein AI (Apo AI). Mean BMI was also higher, as was the prevalence of smokers and subjects with a history of hypertension. In univariate analysis, the odds ratios for TG > or = 1.6 mmol/l, LDL-cholesterol > or = 4.1 mmol/l, VLDL-cholesterol > or = 0.73 mmol/l, Apo B > or = 104 mg/dl were of the same order of magnitude as being a current smoker, having a BMI > or = 24.3 kg/m2, and a history of hypertension. High HDL-cholesterol (> or = 1.39 mmol/l) and Apo AI (> or = 139 mg/dl) were protective factors. The odds ratios for successively higher quartile values of cholesterol were not statistically significant. Multiple logistic regression identified smoking habit, history of hypertension, obesity, high Apo B and low Apo AI concentrations as independent risk factors for myocardial infarction. CONCLUSIONS In a Chinese population, low serum Apo AI and high Apo B are risk factors for myocardial infarction of a comparable magnitude to smoking, hypertension and obesity.

Falls and hip fracture in Hong Kong Chinese

The risk factors for hip fracture were studied in four hundred patients and eight hundred community and hospital controls. Falling was found to be important as a direct cause of fracture. A history of falls was a significant risk factor for hip fracture in men and women younger than 70, but was less important in older men and women. Medical conditions and treatments did not occur more frequently in hip fracture patients with a history of falls than in patients without, and the patients with a history of falls was not less ambulant than patients without. Regular weight-bearing exercise programmes are recommended as a practical preventive measure for falls and hip fractures.

Intake and blood levels of some minerals in an elderly Chinese population

Twenty-four hour intakes of potassium, calcium, and iron, and plasma concentration of potassium, copper and zinc were determined in a cluster sample of 400 apparently healthy subjects aged 60 years and over living in the community. Potassium and calcium intakes were lower in older men and lower in men compared to women. Both were much lower than intakes reported among Caucasian elderly, while iron intakes are comparable. Plasma potassium concentration was lower than values from studies of all ages and from studies of Caucasian elderly subjects. Copper and zinc concentrations were comparable to published values for adults of all ages. The significance of low potassium and calcium intake among elderly subjects in the population is discussed.

Risk factors in non-insulin dependent diabetes mellitus in elderly Chinese in Hong Kong.

The early life environment, 24 h nutrient intake, body mass index, blood pressure and plasma zinc levels among 42 non-insulin dependent diabetic subjects living in sheltered housing were compared to 126 age and sex matched controls from the same community. A high body mass index and systolic blood pressure were the only risk factors. The association with systolic blood pressure was present only among non-obese subjects. No difference in nutrient intake was found. When nutrient intake from all 427 subjects living in sheltered housing was compared to other countries with a higher prevalence of NIDDM, the diet of Chinese subjects consisted of a lower percentage of fat calories and a higher percentage of protein and carbohydrate calories.