BACKGROUNDThere are studies suggesting smoking may increase the risk of type 2 diabetes. Effects of smoking on insulin secretion and insulin resistance (IR) are, however, controversial.

METHODSThis is a cross-sectional study. Since there were very few smokers among Hong Kong Chinese women, only men (n = 1068) were analyzed in this report. Fasting and 2-hour plasma glucose and insulin were measured. Insulinogenic index as well as beta-cell function and IR based on homeostatic model assessment (HOMA) by computer model (HOMA Calculator v2.2) were calculated.

RESULTSOf the 1068 men, 147 had newly diagnosed diabetes, 131 newly diagnosed impaired glucose tolerance (IGT) and 790 were non-diabetic normal controls. Smokers had similar fasting and 2-hour insulin levels, insulinogenic index and HOMA derived beta-cell function as compared to non-smokers in the groups with diabetes, IGT or normal oral glucose tolerance test (OGTT). IR was also similar between smokers, ex-smokers and non-smokers in those with normal OGTT. In men with IGT or diabetes, after adjustment for age and body mass index, smokers were more insulin resistant as compared to non-smokers (IR, IGT: 1.59 +/- 1.07 vs 1.03 +/- 0.54, P < 0.05; diabetes: 1.96 +/- 1.36 vs 1.06 +/- 0.45, P < 0.01). With Logistic regression analysis, comparing smokers and non-smokers, IR was independently associated with smoking (odds ratio (95% CI), IGT: 2.23 (1.05, 4.71); diabetes: 3.92 (1.22, 12.58)). None of the other insulin parameters enter into the model among those with normal OGTT or comparing ex-smokers and non-smoker or smokers and ex-smokers.

CONCLUSIONSIn Chinese men, smoking did not show any direct association with insulin levels and pancreatic insulin secretion. Smoking men with IGT or diabetes appeared more insulin resistant than their non-smoking counterparts.

Adult ; Female ; Glucose Intolerance ; metabolism ; Humans ; Insulin ; secretion ; Insulin Resistance ; Insulin-Secreting Cells ; secretion ; Male ; Middle Aged ; Smoking ; metabolism

BACKGROUNDObesity is now an epidemic in most parts of the world. In this cross sectional study, we report the most recent data on obesity in Hong Kong Chinese working population and compare the changes over 10 years.

METHODSBetween July 2000 and March 2002, 5882 adult subjects from the working class in Hong Kong were recruited (2716 men (46.2%) and 3166 women (53.8%)). They were randomly selected using computer generated codes according to the distribution of occupational groups. Results of this study were compared with the data collected from a prevalence survey for cardiovascular risk factors in a Hong Kong Chinese working population conducted in 1990 (1513 subjects, 910 men (60.1%) and 603 women (39.9%)).

RESULTSStandardized percentages of overweight, obesity, and central obesity, in Hong Kong Chinese working population were 59.7%, 35.0%, 26.7% in men and 32.0%, 21.7%, 26.7% in women. Compared to the data collected in 1990, the percentage of obesity increased by 5% in men and reduced by 6% in women. The percentage of central obesity doubled in men (from 12.2% to 26.7%) but remained stable in women.

CONCLUSIONSThere is a doubling of the percentage of central obesity in Hong Kong Chinese working men over previous decade. Education and proper lifestyle modification program to tackle this social health issue are urgently indicated.

Adolescent ; Adult ; Aged ; Female ; Hong Kong ; epidemiology ; Humans ; Male ; Middle Aged ; Obesity ; epidemiology ; Time Factors ; Work