Controlling BP levels improve patient survival
Recent study findings reinforce the importance of avoiding hypertension. One recent study revealed that people who maintained or reduced their BP to normal levels during middle age have the lowest lifetime risk of cardiovascular disease (CVD), and those with an increase in BP have the highest risk (Circulation. 2012;125:37-44).
Researchers recorded baseline BP readings for 61,585 men and women from an average of 14 years earlier, tracking changes in those measurements until the person reached age 55 years and then until the person experienced a MI or stroke, died or reached age 95 years.
Patients who maintained BP at or reduced it to normal levels by age 55 years had a CVD lifetime risk of 22%-41%. Persons who had already developed hypertension by age 55 years had a CVD lifetime risk for of 42%-69%. To reduce patients' CVD lifetime risk, prevention efforts should continue to emphasize the importance of lowering BP and avoiding or delaying the incidence of hypertension.
In another large, long-term trial — the Systolic Hypertension in the Elderly Program (SHEP) — 2,365 patients who underwent 4.5 years of treatment with the diuretic chlorthalidone exhibited significantly lower mortality and increased life expectancy free from cardiovascular death at nearly 22 years of follow-up than did 2,371 subjects taking a placebo.
When originally conducted between 1985 and 1990, the SHEP trial demonstrated that among patients aged 60 years and older with isolated systolic hypertension, antihypertensive therapy with chlorthalidone-based stepped-care therapy resulted in a lower rate of cardiovascular events than did placebo. However, at that time effects on mortality were not significant.
Recently, investigators reported on the gain in life expectancy at the 22-year follow-up of SHEP participants who had been randomized to active therapy (JAMA. 2011; 306:2588-2593). By that point, life expectancy gain was 158 days for cardiovascular death and 105 days for death from all causes. This translated to approximately one day gained in life expectancy free from cardiovascular death per one month of treatment, and approximately half a day gained in life expectancy for all-cause mortality per one month of treatment.