The incidence of stroke appears to have decreased by roughly 40 percent in the United Kingdom over the past 20 years, a period marked by a significant increase in use of blood pressure- and cholesterol-lowering drugs, according to an article in the June 12th issue of the Lancet. The authors note that stroke is the largest cause of long-term neurological disability and the single most costly condition for the UK National Health Service.

Professor Peter Rothwell and his British colleagues assessed changes in stroke and transient ischemic attack rates in two studies in Oxfordshire, the Oxford Community Stroke Project (OCSP), 1981-1984, and the Oxford Vascular Study (OXVASC), 2002-2004.

The population aged 75 years or older increased by one third over the 20 years between the two studies. However, age-adjusted occurrence of first stroke was reduced by around 30 percent in the second study compared with the expected incidence based on data from the earlier study. For major disabling or fatal strokes the reduction was 40 percent.

The reduction was associated with increased use of blood-pressure lowering and cholesterol-lowering drugs and associated substantial reductions in blood pressure, cholesterol, and other risk factors.

Dr. Rothwell commented, "Although we cannot prove conclusively that the major fall in stroke incidence is a direct result of the measured increase in use of preventive medication, a causal link is highly likely. There remains significant under-treatment of individuals at risk of stroke in the community and so further major reductions in stroke incidence should be possible."

In an accompanying Commentary, Valery Feigin and Stephen Vander Hoorn of New Zealand concluded, "Rothwell and colleagues' state-of-the-art study makes an important contribution to knowledge about stroke epidemiology."