Antihypertensive efficacy and tolerability of different drug regimens in isolated systolic hypertension in the elderly

The pharmacological treatment, mainly based on diuretics, ofisolated systolic hypertension (ISH) has recently been shownto reduce the risk of stroke and coronary heart disease in theelderly. The purpose of this study was to compare the antithypertensiveeffect and tolerability of different drug regimens in elderlysubjects with ISH (systolic blood pressure—SBP —160mmHg and diastolic blood pressure — DBP — <90mmHg). A multicentre, randomized, controlled open trial wasplanned in the general practice setting. Four widely used treatmentschedules were tested: hydrochlorothiazide 25 mg plus amiloride2·5 mg (H+Am), nifedipine slow release 20 mg (N), atenolol50 mg (At) and atenolol 25mg plus chlorthalidone 6·25mg (At+C). After a baseline evaluation, 308 patients (76·3% female,mean age 75·3 ± 7·1 years) were randomizedand followed up for 6 months. After 3 months the drug dosagewas doubled if the systolic blood pressure goal (SBP<160mmHg and SBP reduction of at least 20 mmHg) had not been reachedNinety-four subjects (30·5%) presented contraindicationsto ß-blockers. At the 3rd- and 6th-month visits alltreatment groups, except At, showed a significant reductionin SBP compared to the control group; DBP showed no significantreduction in any group at any time. At the end of the follow-upthe percentage of hypertensives who had reached the BP goalwas 14·6% in the control group, 52·9% in H+Am,54·8% in N, 28·6% in At and 52·2% in At+C.Over two-thirds of the patients on H+Am or N, and about 50%of those on At or At+ C at 6 months were taking the medicationat low dose. The rate of therapy discontinuation due to side effects duringfollow-up was significantly different among the drug regimenstested: 1·9% in the H+Am group compared to 12·5%,19·2% and 14·8% respectively in N, At and At+Cgroups (P<0·05 for H+Am vs At). The proportion ofsubjects who spontaneously reported, mild adverse effects after3 and 6 months of therapy was not signficantly different inthe study groups, even if an excess was observed in the N groupat 3 months. In conclusion, these data suggest that. diuretics are a firstchoice in the treatment of ISH, because of their hypotensiveefficacy and acceptability; nifedipine, if well tolerated, isan effective alternative to diuretics; a high proportion ofelderly patient with ISH present contraindications to ß-blockers,and atenolol has a poor antihypertensive effect.