How does smoking affect the risk of stroke?

Smoking significantly increases the risk of stroke primarily because it raises blood pressure. The chemicals present in tobacco smoke can cause blood vessels to constrict and become narrower, leading to increased peripheral resistance in the circulatory system. This constriction raises blood pressure, which is a well-established risk factor for stroke.

Additionally, smoking contributes to the buildup of plaque in the arteries (atherosclerosis), making them less flexible and more prone to blockage, which can also lead to a stroke. Maintaining high blood pressure due to smoking leads to damage in the arteries over time, increasing the likelihood of both transient ischemic attacks (TIA) and ischemic strokes.

The other options present inaccurate effects of smoking on cardiovascular health. For example, smoking does not lower blood pressure or reduce stress on blood vessel walls; in fact, it does the opposite. Moreover, smoking is associated with reduced, not enhanced, flexibility of blood vessels, which can further compound the risk factors for stroke.