Influence of baseline values. II: Variations in plasma lipoprotein fractions during doxazosin treatment for hypertension.

Forty-two Nigerian hypertensive men and women aged 40 to 60 years treated with doxazosin for 12 consecutive months were studied. Before the doxazosin therapy, all the patients had their baseline lipoprotein fractions determined and that was used to classify the patients into 'low', 'medium' and 'high' baseline values. The assays were repeated 4 times at every 3 months during the 12-month treatment with doxazosin. The mean high density lipoprotein-cholesterol (HDLC) levels were significantly reduced in the patients with high baseline values, and remained unchanged for the patients with low and medium baseline values during doxazosin therapy. Low density lipoprotein-cholesterol (LDLC) levels were apparently reduced in all the groups and this was significant for the patients with high baseline values. The mean levels of very low density lipoprotein-cholesterol (VLDLC) increased in the patients with low baseline values, and decreased in the patients with medium and high baseline values during the 12 months of doxazosin therapy. We therefore conclude that although the overall risk of developing coronary heart disease as measured by the risk predictor index LDLC/HDLC ratio was not affected by the baseline values of the patients, it is, however, important to note that adverse lipoprotein changes such as raised VLDLC and reduced HDLC may be seen in patients with low and high baseline values, respectively, during doxazosin treatment for hypertension. These observations will call for more serious monitoring of these lipoprotein fractions in patients with variable baseline values, by physicians and all health workers concerned during doxazosin treatment for hypertension.