Heavy smokers with hypertension benefit most from stopping

Stroke remains the third leading cause of death in most Western countries and is second only to myocardial infarction as a cause of cardiovascular death. Many epidemiological studies have established cigarette smoking as an important risk factor for stroke. Until recently, however, this relation was based on observational studies and the effects of smoking were thought to be synergistic with hypertension, diabetes mellitus, glucose intolerance, age, hypercholesterolaemia, and pre-existing cardiovascular disease.1 Now we have definite evidence that smoking itself has a direct causal effect on stroke.

The relation between smoking and atherosclerosis was observed as early as 1908 by Buerger, who noted severe distal ischaemia among young male addicted smokers.2 The earliest report associating stroke and extracranial arterial disease is credited to Gowers, who in 1875 showed left carotid artery occlusion in a patient with right hemiplegia and loss of sight in the left eye.3

The Framingham Heart Study was among the first to assess these the …