Age-stratified and blood-pressure-stratified effects of blood-pressure-lowering pharmacotherapy for the prevention of cardiovascular disease and death: an individual participant-level data meta-analysis
Meta-analysis (51 RCTs, n=358,707) found that pharmacological blood pressure (BP) reduction is effective into old age, with no evidence that relative risk reductions for prevention of major CV events vary by systolic or diastolic BP levels at randomisation, down to <120/70 mm Hg.
Source:
The Lancet
SPS commentary:
The hazard ratios for risk of major CV events per 5 mm Hg reduction in systolic BP for each age group were
0.82 (95% CI 0.76–0.88) age <55 years
0·91 (0.88–0.95) age 55–64 years
0.91 (0.88–0.95) age 65–74 years
0.91 (0.87–0.96) age 75–84 years,
0.99 (0.87–1.12) age ≥85 years
Similar patterns of proportional risk reductions were observed for a 3 mm Hg reduction in diastolic blood pressure. Absolute risk reductions for major cardiovascular events varied by age and were larger in older groups.
According to a commentary, in 2002, the 1-million participant Prospective Studies Collaboration reported that the relative difference in risk of vascular mortality for a given difference in BP was about the same across a BP range from over 170/100 mm Hg down to at least 115/75 mm Hg. These findings suggested that the most meaningful definition of hypertension, for people aged 40–89 years, might be a BP as low as 115/75 mm Hg—i.e. the level above which risk of vascular disease increases monotonically with increasing BP. It notes these observational epidemiological findings have now been confirmed in this current meta-analysis, at least among people up to age 85 years, as there was had insufficient data to assess whether there were also benefits in older people. It adds that nevertheless, it is reassuring that all-cause mortality was not increased in treated people aged 85 years and older, supporting the common practice of continuing BP-lowering treatment in these patients, unless other good reasons not to exist. Furthermore, as similar relative risk reductions from BP lowering down to at least 120/70 mm Hg, for people at least up to age 85 years, there is a need for trials on BP lowering in healthy people older than 85 years with levels above 120/70 mm Hg as they are generally at the highest risk of vascular disease and so have the most to gain from BP-lowering ~ 120/70 mm Hg, the magnitude of their predicted (absolute) vascular risk, rather than an arbitrary BP level, should inform the intensity and type of management.