Current issues of ACP Journal Club are published in Annals of Internal Medicine


Therapeutics

Review: Drug treatment of hypertension reduces mortality in the elderly

ACP J Club. 1995 Jan-Feb;122:1. doi:10.7326/ACPJC-1995-122-1-001


Source Citation

Insua JT, Sacks HS, Lau TS, et al. Drug treatment of hypertension in the elderly: a meta-analysis. Ann Intern Med. 1994 Sep 1;121:355-62.


Abstract

Objective

To determine, using meta-analysis, the effectiveness of antihypertensive drug treatment in reducing all-cause and cause-specific mortality, stroke, and coronary heart disease in older persons.

Data sources

Studies were identified through a MEDLINE search (January 1980 to February 1992) using the keywords hypertension, elderly or aged, and randomized controlled trials. Additional studies were identified from review articles, a review of Current Contents, and bibliographies of relevant papers.

Study selection

Studies were selected if patients were randomly assigned to treatment groups; the patients had diastolic, systolic, or isolated systolic hypertension on at least 1 measurement; the interventions included any antihypertensive drug treatment administered in any form; and the end points were numerically identifiable at 5 years for elderly patients.

Data extraction

Mortality and morbidity end points were extracted for patients > 59 years of age. Data were extracted by 2 readers who were blinded to treatment assignment, and the final result was reached by consensus.

Main results

31 trials were identified and 9 trials with 15 559 patients > 59 years of age were included in the analysis (7750 treated patients, 7809 control patients). All trials included stepped care except for 1 that used methyldopa only. All of the stepped-care regimens included treatment with diuretic agents and 5 included β-blockers. In 3 trials, no placebo was used in the control group. Meta-analysis used intention-to-treat data. Patients in antihypertensive drug treatment groups compared with those in control groups had lower rates for all-cause mortality (P < 0.01), fatal strokes (P < 0.001), nonfatal strokes (P < 0.001), and fatal coronary events (P < 0.001) (Table).

Conclusion

Drug treatment of hypertension in patients aged > 59 years reduces total mortality and cerebrovascular and cardiovascular morbidity and mortality.

Sources of funding: In part, Robert Wood Johnson, Jr. Charitable Trust and Agency for Health Care Policy and Research of the United States Public Health Service.

For article reprint: Dr. H.S. Sacks, Clinical Trials Unit, Mount Sinai Medical Center, Box 1042, New York, NY 10029, USA. FAX 212-860-4607.


Table. Antihypertensive drug treatment vs placebo in the elderly*

Outcomes Weighted event rates RRR (95% CI) NNT (CI)
Antihypertensive drug treatment Placebo
All-cause mortality 12.3% 13.7% 10% (3 to 17) 70 (42 to 199)
Fatal stroke 1.5% 1.9% 36% (18 to 51) 247 (142 to 971)
Nonfatal stroke 3.4% 4.9% 35% (23 to 44) 67 (48 to 111)
Fatal coronary event 3.5% 4.5% 24% (11 to 35) 102 (66 to 231)

*Abbreviations defined in Glossary; RRR, NNT, and CI calculated from data in article.


Commentary

The meta-analysis by Insua and colleagues is a useful summary of the effect of antihypertensive drug treatment in large trials among elderly patients. Exclusions cited by the authors appear valid, and the reduction in both stroke mortality and coronary artery disease mortality is impressive.

The results of this study differ from those of previous studies in 2 respects. First, the conclusion that treatment effect decreases with age is contrary to the findings of several studies (1, 2). Second, in this study, the existence of a J-curve phenomenon was thought to be nonsignificant, but other evidence suggests that lowering diastolic blood pressure levels to < 85 mm Hg is associated with an increased risk for cardiac events, particularly in elderly patients (3).

No analysis was provided in the report about the extent to which blood pressure should be lowered. This factor is discussed in a recent review that concluded that systolic blood pressure values > 180 mm Hg should be reduced to < 160 mm Hg and that systolic values between 160 and 180 mm Hg should be reduced by 20 mm Hg (4).

The authors comment on a trend toward increased incidence of nonvascular deaths (not defined) without discussing the reasons for this possible phenomenon. A recent study suggests at least 1 explanation: hypokalemia-associated mortality (5).

Eugene L Coodley, MD
University of California, IrvineLong Beach, California, USA


References

1. SHEP Cooperative Research Group. Prevention of stroke by antihypertensive drug treatment in older persons with isolated systolic hypertension. Final results of the Systolic Hypertension in the Elderly Program (SHEP). JAMA. 1991;265:3255-64.

2. Staessen J, Fagard R, Van Hoof R, Amery A. Intervention trials in elderly hypertensive patients: a review. J Hypertens. Suppl 1990;4:S63-7.

3. Fletcher AE, Bulpitt CJ. How far should blood pressure be lowered? N Engl J Med. 1992;326:251-4.

4. The fifth report of the Joint National Committee on Detection, Evaluation and Treatment of High Blood Pressure. Arch Intern Med. 1993;153:154-83.

5. Siscovick DS, Raghunathan TE, Psaty BM, et al. Diuretic therapy for hypertension and the risk of primary cardiac arrest. N Engl J Med. 1994;330:1852-7.