Background: Beneficial clinical effects of treatment with antihypertensive drugs have been shown in middle-aged patients and in those hypertensive patients over 60 years old, but whether treatment is beneficial in patients over 80 years old is not known.
Methods: We collected data from all participants aged 80 years and over in randomised controlled trials of antihypertensive drugs through direct contact with study investigators. Our primary outcome was fatal and non-fatal stroke. Secondary outcomes were death from all causes, cardiovascular death, fatal and non-fatal major coronary and cardiovascular events, and heart failure.
Findings: There were 57 strokes and 34 deaths among 874 actively treated patients, compared with 77 strokes and 28 stroke deaths among 796 controls, representing 1 non-fatal stroke prevented for about 100 patients treated each year. The meta-analysis of data from 1670 participants aged 80 years or older suggested that treatment prevented 34% (95% CI 8-52) of strokes. Rates of major cardiovascular events and heart failure were significantly decreased, by 22% and 39%, respectively. However, there was no treatment benefit for cardiovascular death, and a non-significant 6% (-5 to 18) relative excess of death from all causes.
Interpretations: The inconclusive findings for mortality contrast with the benefit of treatment for non-fatal events. Results of a large-scale specific trial are needed for definite conclusion that antihypertensive treatment is beneficial in very elderly hypertensive patients. Meanwhile, an age threshold beyond which hypertension should not be treated cannot be justified.