Serum lipids and their relationship with other coronary risk factors in healthy subjects in a city clinic

Over a thousand subjects who visited a city private medical clinic for health screening and advice were examined for their lipid profile and other cardiovascular risk factors. The mean TC, TG, LDL-C and HDL-C were 5.43, 1.45, 3.61 and 1.15 mmol/l. Their derived ratios viz, TC:HDL-C and LDL:HDL-C were 5.11 and 3.43 respectively. The prevalence of hyperlipidaemia was moderately high. Of the subjects studied 58.5% had elevated serum cholesterol, 14.8% had raised triglycerides, 64.9% had raised LDL-C and 20.8% had low HDL-C. Male subjects generally showed higher mean values and abnormality frequency in TC, TG, LDL-C, TC:HDL-C and LDL:HDL-C as compared to female subjects. Although significant ethnic differences were not detected for certain lipid parameters (e.g. TC, TG and HDL-C), the Indians appeared to have higher mean lipid values (except HDL-C), and higher percentage abnormality for all the lipid parameters as compared to the Chinese and the Malays. In correlation studies, the following lipid parameters:- TC versus TG, LDL-C, TC:HDL-C; TG versus TC:HDL-C and LDL:HDL-C; LDL-C versus TC:HDL-C and LDL:HDL-C; were positively correlated. On the other hand, TC versus HDL-C, TG versus HDL-C, LDL-C and HDL-C, and HDL-C versus TC:HDL-C and LDL:HDL-C were negatively correlated. The coronary risk factors which generally showed positive correlations with lipid parameters were BMI and blood pressure. Positive correlations were also recorded between fasting blood glucose and TG; uric acid with TG, TC:HDL-C and LDL:HDL-C. In contrast, risk factors of negative correlations were observed between HDL-C and the coronary risk factors of BMI, diastolic blood pressure and uric acid. Smoking showed raised per cent lipid abnormality for TG, HDL-C, TC:HDL-C and LDL:HDL-C. Alcohol consumption also increased the mean level and abnormality frequency for TG. The implication of this investigation is discussed.