Antihypertensive treatment and plasma lipoprotein levels. The associations in data from a population study.

In clinical trials, antihypertensive therapy with beta blockers and methyldopa has resulted in adverse changes in high-density lipoprotein cholesterol levels. To investigate whether such effects can be observed in a general population in which beta blockers and methyldopa are prescribed widely for the treatment of high blood pressure, plasma lipid and lipoprotein levels were compared in subjects receiving antihypertensive treatment, subjects with untreated high blood pressure, and subjects with normal blood pressure; these subjects were drawn from a random sample of 5,603 men and women screened in a national study of risk-factor prevalence in Australia. In both sexes, high-density lipoprotein cholesterol levels were lower in the group receiving treatment for hypertension than in the other groups (p less than 0.001). High-density lipoprotein cholesterol levels in normotensive subjects and subjects with untreated high blood pressure were identical. In men, triglyceride levels and the ratio of total cholesterol to high-density lipoprotein cholesterol were higher in the group receiving treatment than in the other groups (p less than 0.001 and p less than 0.05, respectively). In both sexes, the differences in plasma lipids and lipoproteins between treated and untreated hypertensive groups were independent of age, body mass index, alcohol consumption, and smoking. More than 40 percent of untreated hypertensive subjects and more than 50 percent of treated hypertensive subjects had elevated total cholesterol levels (greater than or equal to 252 mg/dl) or an elevated ratio of total cholesterol to high-density lipoprotein cholesterol (greater than or equal to 6.0) in comparison with less than 30 percent of normotensive subjects. These results indicate that even without treatment, a large proportion of persons with high blood pressure had a significant abnormality in plasma cholesterol. The observation of a lower high-density lipoprotein cholesterol level in subjects receiving treatment for high blood pressure suggests that antihypertensive therapy as prescribed in this study population had worsened the already poor plasma lipid and lipoprotein profile of the average hypertensive patient.