Serum lipoproteins in patients with mild renal disease treated with the diuretic muzolimine

Comparative effects of doxazosin and hydrochlorothiazide on serum lipids and blood pressure in essential hypertension

The efficacy and safety of doxazosin (mean dosage 6.9 mg, range 1 to 16) in the treatment of essential hypertension were compared in a double-blind study with those of hydrochlorothiazide (HCTZ) (mean dosage, 84.6 mg, range 25 to 100) in 104 hypertensive patients treated once daily for 6 months. Thirty-five patients were also assessed for comparative effects of the 2 agents on serum lipid parameters. Doxazosin produced potentially favorable changes from baseline in the concentrations of serum lipid fractions (total triglycerides, total cholesterol, high density lipoprotein [HDL] cholesterol and the derived HDL/total cholesterol ratio) compared with HCTZ. The decreases in total triglyceride and total cholesterol concentrations and an increase in the HDL/total cholesterol ratio were significantly different (p less than 0.006) from the opposite changes observed with HCTZ. Clinically relevant decreases from baseline in supine and standing blood pressures at 24 hours after administration did not significantly differ between the 2 agents. The incidence and severity of side effects were similar for both drugs. Three patients receiving doxazosin and 6 receiving HCTZ were withdrawn due to drug-related clinical side effects including 2 patients receiving HCTZ who were withdrawn because of laboratory test abnormalities. Eight HCTZ- and 1 doxazosin-treated patients developed hypokalemia and 6 HCTZ-treated patients developed hyperuricemia. These findings indicate that doxazosin and HCTZ provide comparable antihypertensive efficacy after 6 months of treatment using a once-daily regimen, but doxazosin produces a beneficial effect on the serum lipid profile as well as fewer biochemical aberrations.

Increased serum high-density lipoprotein cholesterol in hypertensive men treated with the potent vasodilator carprazidil

The effects of the potent arteriolar vasodilator carprazidil on serum lipoproteins and various clinical, biochemical and endocrine parameters were assessed in 15 men with mild to moderate essential hypertension. Following a carprazidil monotherapy (average dose 50 to 60 mg/d) of 8 weeks (N = 15) or 16 weeks (N = 12) duration, blood pressure was decreased significantly (P less than 0.01), while serum high-density lipoprotein cholesterol (+ 26% and + 24%, respectively; P less than 0.01) and the alpha-lipoprotein fraction (+ 26% and + 41%) were increased. Low- and very low-density lipoprotein cholesterol, triglycerides, as well as mean body weight, blood and plasma volume, heart rate, and plasma renin, aldosterone, norepinephrine, and epinephrine were not consistently altered. These results indicate that treatment of hypertensive men with carprazidil in modest dosage may have a favorable influence both on blood pressure and serum lipoproteins.

Effects of antihypertensive therapy on serum lipoproteins

Several drugs used for standard antihypertensive therapy may also interact with the lipoprotein metabolism. The following has been observed after 1 to 12 months of treatment. Various thiazide-type diuretics may significantly increase the potentially atherogenic serum low-density-lipoprotein cholesterol (LDL-C) and/or very-LDL-C-fractions, while the antiatherogenic high-density-lipoprotein cholesterol (HDL-C) is largely unchanged. Certain loop-diuretics also increase the LDL-C/HDL-C ratio and both types of diuretics elevated serum triglycerides (Tg) in some but not all studies. LDL-C was increased in diuretic-treated men and in chlorthalidone-treated postmenopausal women, but not in chlorthalidone-treated premenopausal women. The latter may be protected from this effect. Only two diuretics evaluated, namely indapamide and spironolactone, had no apparent influence on lipoproteins. Beta-blocker monotherapy may often increase Tg and slightly decrease HDL-C. The magnitude of these changes did not distinctly differ between highly cardioselective and nonselective beta-blockers, but it was less pronounced on beta-blockers than on those without intrinsic sympatholytic activity. Other sympatholytics such as reserpine, methyldopa, clonidine, debrisoquine, the alpha-beta-blocker labetalol, or the postsynaptic alpha-blocker, prazosin, did not affect or even slightly decrease Tg or total C, LDL-C, and very-LDL-C values. With combinations, a tendency for increased Tg and lower HDL-C was also apparent during thiazide-type diuretic-beta-blocker therapy. However, diuretic-induced increases in LDL-C were prevented or reversed by concomitant beta-blockade, but not by reserpine, methyldopa, or clonidine. Monotherapy with the potent direct vasodilator, carprazidil, improved blood pressure and significantly increased HDL-C. Prospective long-term studies are needed to clarify the course and the pathogenic and prognostic relevance of lipoprotein changes induced by certain diuretics or beta-blockers.