The Eurevie Study: contrasting effect of piretanide and thiazides in mild to moderate hypertension. 1997
This study compares the loop diuretic piretanide 6 mg in a slow-release formulation (PIR) with hydrochlorothiazide 25 mg (HCT) and the fixed combination altizide 15 mg-spironolactone 25 mg (ALT-SP) in hypertension. 1105 mild to moderate hypertensive patients entered a three-week placebo wash-out period; 899 were randomized in a 6-month, double-blind, parallel group treatment phase; 800 completed the study. Primary end-points; serum potassium concentration and quality of life at one month; secondary end-points: ionic, renal and metabolic variables; blood pressure (BP) measurements. HCT and ALT-SP were compared only to PIR using Dunnett's or chi 2 tests. RESULTS No difference was found for the overall quality of life. No change of serum potassium concentration at one month was found in PIR while small decreases were detected with ALT-SP (-0.1 mM) and HCT (-0.26 mM). Serum creatinine concentration increased significantly in ALT-SP when compared to PIR. All the drugs were effective in reducing BP: HCT had a higher rate of responders than PIR with similar mean BP falls and ALT-SP induced greater falls in blood pressure. CONCLUSIONS PIR proves to be a potent antihypertensive drug without significant effect on serum electrolytes, plasma glucose and lipids. HCT was slightly more potent but induced a fall in serum potassium concentration with a significant risk of hypokalaemia. The addition of SP to ALT led to a more potent diuretic with a higher level of serum potassium and plasma creatinine disturbances.