Abstract
After an initial washout period of 4 weeks (wk), seventeen patients were started on prazosin hydrochloride (P) and fifteen patients were started on trichlormethiazide (T) according to a single blind crossover protocol of two 8 wk-periods with a washout of 8 wk in order to evaluate the effects of P and T on serum lipids in hypertensive outpatients. Patients with diabetes mellitus were excluded. Casual blood pressure and pulse rate in the sitting position, and serum total cholesterol (T. ch), serum triglyceride (TG) and serum HDL-cholesterol (HDL-ch) concentrations were monitored at the beginning of each sequence and at 8 wk interval. Finally, nine patients out of seventeen and seven patients out of fifteen could complete each crossover trial, respectively. In addition, eight patients out of seventeen and eight patients out of fifteen could complete only the first part of each crossover trial, respectively. Therefore, results of respective eight patients were summarized as the open trial together with those of crossover trial.
In the open trial, P (n=24) and T (n=24) significantly decreased diastolic blood pressures (p<0.044 and p<0.022), respectively. However, systolic blood pressures and pulse rates were remained unchanged. P significantly decreased TG levels (p<0.003) and increased HDL-ch levels (p<0.009). T did not modify serum lipid levels. When serum lipid levels were stratified at specified level, P significantly decreased both T. ch levels more than 220mg/dl (p<0.05) and TG levels more than 150mg/dl (p<0.01). Furthermore, P significantly increased both HDL-ch levels less than (p<0.05) and more than 45mg/dl (p<0.05). T did not modify stratified lipid levels.
In the crossover trial, when P was given first (n=9), increase of HDL-ch levels was significant (p<0.01), but changes of T. ch and TG were minimal. Upon shifting P to placebo, decrease of HDL-ch levels was significant (p<0.05), but changes of T. ch and TG levels were also minimal. When placebo was shifted to T, T. ch, TG and HDL-ch levels remained unchanged. Furthermore, when T was given first (n=7), increase of TG levels was significant (p<0.05), but changes of T. ch and HDL-ch levels were minimal. Upon shifting T to placebo, changes of T. ch, TG and HDL-ch levels were also minimal. When placebo was shifted to P, decrease of TG levels was significant (p<0.05), but T. ch and HDL-ch levels remained unchanged.
