Metabolic parameters after changing from hydrochlorothiazide to verapamil treatment in hypertension

The effect of verapamil on different metabolic parameters has been studied after changing the treatment of hypertension from hydrochlorothiazide to verapamil monotherapy. Verapamil 80 to 160 mg b.i.d. was continued for 6 months. The antihypertensive efficacy of verapamil was comparable to that of hydrochlorothiazide. Plasma total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides and free fatty acids did not change significantly after the change in treatment; serum total cholesterol, LDL-cholesterol and HDL-cholesterol were 7.28 +/- 1.80 (m +/- SD), 5.11 +/- 1.59 and 1.65 +/- 0.39 mmol/l at the end of the hydrochlorothiazide period and 7.10 +/- 1.92, 5.09 +/- 1.70 and 1.56 +/- 0.35 mmol/l at the end of the verapamil period, respectively. The only statistically significant differences were the increases in total and LDL-cholesterol after three months on verapamil as compared to the basal values before diuretic therapy. Marked changes were not observed in fasting blood glucose, insulin or C-peptide values. Serum uric acid concentration decreased significantly (p less than 0.001) from 326 +/- 66 to 252 +/- 53 mmol/l, and serum potassium level increased significantly (p less than 0.01) from 3.5 +/- 0.4 to 3.9 +/- 0.3 mmol/l, on verapamil as compared to the diuretic period. Serum calcium decreased from 2.45 +/- 0.10 to 2.37 +/- 0.08 mmol/l (p less than 0.01) and calcium excretion increased significantly (p less than 0.01) to 5.43 +/- 2.55 mmol/24 h during verapamil administration from the level of 3.56 +/- 2.78 mmol/24 h whilst on the diuretic.