Meta-analysis. Update on reversal of left ventricular hypertrophy in essential hypertension (a meta-analysis of all randomized double-blind studies until December 1996)
OBJECTIVE: To provide an update on the ability of different antihypertensive drugs to reduce left ventricular hypertrophy in essential hypertension. DATA SOURCES: Relevant medical databases including MEDLINE, BIOSIS PREVIEWS, EMBASE, and SCISEARCH as well as review articles to December 1996. STUDY SELECTION: Meta-analysis of all published articles including only double-blind, randomized, controlled clinical studies with parallel-group design. DATA EXTRACTION: Literature search and data extraction according to a prefixed scheme performed independently by two investigators. The primary parameter was reduction of left ventricular mass by antihypertensive therapy with placebo, diuretics, beta-blockers, calcium channel blockers, or ACE-inhibitors. DATA SYNTHESIS: Fifty studies published till the end of December 1996 were identified. They comprised a total of 1715 patients in 13 placebo (n=165, age: 50+/-3 years) and 89 active treatment arms (n=1550, age: 56+/-10 years) respectively. Overall, for active treatment left ventricular mass index was the more reduced the greater the decrease in systolic blood pressure, (r=0.27; P<0.05), the longer the duration of therapy (r=0.36; P<0.001), and the higher the pretreatment value of left ventricular mass index (r= 0.53; P<0.001). Left ventricular mass index was decreased by 12% with ACE-inhibitors (95% CI: 9.0-14.5%), by 11% with calcium channel blockers (95% CI: 7.8-13.7%), by 5% with beta-blockers (95% CI: 1.2-7.3%) and by 8% with diuretics (95% CI: 3.9-11.1%) (overall P<0.01). Subsequent tests revealed that ACE-inhibitors and calcium channel blockers were more effective than beta-blockers in reducing left ventricular mass index (P<0.05). Similar differences between drug classes were found with regard to effect on left ventricular wall thickness (P<0.05). CONCLUSIONS: Decrease in systolic blood pressure, duration of antihypertensive therapy, degree of pretreatment left ventricular hypertrophy and antihypertensive drug class determined the reduction of left ventricular hypertrophy. ACE-inhibitors and calcium channel blockers were more potent in reducing left ventricular mass than beta-blockers, with diuretics in the intermediate range.