Abstract
The prevalence of hypercholesterolaemia and the frequency of a reduced HDL-cholesterol (at different cholesterol concentrations) were evaluated in a group of 400 diabetic patients attending a single diabetic clinic. Despite regularly supervised diabetes, including dietary advice, over one quarter of the patients had a serum total cholesterol concentration > 6.5 mmol/1, while over a quarter of the non-insulin treated and one eighth of the insulin treated diabetic subjects had an HDL-cholesterol <0.9 mmol/1, with a greater prevalence in the males compared with the females. More than 60% of all the diabetic patients who had a reduced HDL-cholesterol <0.9 mmol/1 also had a total cholesterol concentration <6.5 mmol/1. When the total/HDL-cholesterol ratio was calculated more non-insulin treated subjects had a value >4.5 as compared with insulin treated diabetic patients.
When comparisons were made between an age matched group of diabetic patients (n=185) and a group of non-diabetic subjects attending for a health screen (n=155), the frequencies of serum cholesterol concentrations greater than 5.2, 6.5, and 7.8 mmol/1 were similar for both groups. Significantly greater numbers of diabetic patients had a reduced HDL-cholesterol <0.9 mmol/1 (at any level of serum cholesterol) and a total/HDL cholesterol ratio >4.5.
This study has shown that the measurement of serum total cholesterol concentration alone will not characterize many subjects who are at risk of macrovascular complications due to a reduced HDL-cholesterol. As serum cholesterol and HDL-cholesterol can both be measured in the non-fasting state, routine measurement of HDL-cholesterol together with total cholesterol should be undertaken in all diabetic subjects and in other patient groups at high risk of cardiovascular disease.