Meta-analyses support broad antihypertensive strategy

16 May 2008

MedWire News: Meta-analyses findings support early and aggressive management of hypertension across all age groups, experts say in the British Medical Journal.

Furthermore, the data provide reassurance that the benefits of blood-pressure lowering regimens based on different drug classes are largely comparable, despite a relative lack of data outside the age group 50-80 years, authors of the study believe.

"These findings should greatly simplify decision making for millions of clinicians around the world," remark F Turnbull and co-investigators from the Blood Pressure Lowering Treatment Trialists' Collaboration (BPLTTC).

They analyzed data from 31 trials, involving nearly 200,000 participants, to compare the effects of blood-pressure lowering on a primary outcome of total major cardiovascular events between individuals aged under 65 years and those 65 years or older.

The team reports in the British Medical Journal that there was no evidence of any difference in reductions in the primary endpoint in different age groups or with different regimens.

For instance, in comparison with placebo, ACE inhibitors reduced blood pressure (BP) by 4.6/2.1 mmHg in younger participants and by 4.2/2.0 mmHg in older participants, and reduced the relative risk for the primary endpoint by 24% and 17%, respectively.

Calcium antagonists gave corresponding BP reductions of 7.2/2.9 mmHg and 9.3/3.8 mmHg and relative risk reductions for the primary endpoint of 16% and 26%.

Tests for interactions confirmed risk reductions were not affected by age.

"Likewise, in the overviews of trials comparing BP-lowering regimens based on different drug classes there was no difference in the proportional reductions in total major cardiovascular events observed between age groups for any comparison," the authors write.

Subsidiary analyses using age as a continuous variable confirmed these findings.

Turnbull et al conclude: "Our results confirm the benefits of effective control of blood pressure in older and younger adults."

In an accompanying editorial, Jan Staessen (Campus Gasthuisberg, Leuven, Belgium) and colleagues commented: "The BPLTTC analysis strongly supports the early and aggressive management of hypertension, irrespective of age.

"Clinicians should be aware that similar proportional reductions in risk across the age range translate into much higher absolute benefit in older patients than in younger ones."

Br Med J 2008; 336: 1121-1123