Smoking and High Blood Pressure

Smoking is a major risk factor for cardiovascular diseases. Although a direct causal relationship between high blood pressure and smoking has not been established yet, but cigarette smoking is a proven independent cardiovascular disease risk factor. Moreover, people with hypertension, who continue smoking cigarettes, are at higher risk of developing severe forms of hypertension like malignant hypertension. Cigarette smoking cessation is one of the most important lifestyle modifications suggested to fight the high blood pressure. Cessation of cigarette smoking helps in prevention of a large number of diseases, and not just high blood pressure.

Numerous mechanisms have been suggested for the damage caused by cigarette smoking, and the resultant increased risk of cardiovascular diseases. Some of the most important ones are damage to the inner lining of the arteries, stiffening of the arteries, alterations in the blood lipid profile, changes in the levels of antithrombotic and prothrombotic factors, increased rate of development of atherosclerosis and its complications, activation of sympathetic nervous system and increased free radicals. The exact mechanism and relative importance of each by which smoking has its harmful effect on health is a still a topic of active research.

Cigarette smoking causes a transient increase in the blood pressure immediately after smoking by inducing constriction of the arteries. Chronic smoking has been found to result in hypertension in animal studies. Also, some recent studies indicate a relationship between total amounts of cigarettes smoked (lifetime cigarette consumption) and hypertension. However, a direct causal relationship between smoking and hypertension has not been confirmed yet and significant blood pressure reduction is not observed after cessation of chronic cigarette smoking. However, this could be because smoking affects central blood pressure more than the peripheral blood pressure. The blood pressure measured in the arm is peripheral blood pressure, but the central blood pressure is more important for the organ damage caused by hypertension. Smoking cessation does improve the future risk of cardiovascular complications and death, and it is believed that smoking cessation reduces central blood pressure and not the peripheral blood pressure (which is measured in the arm). So even if your blood pressure stays the same despite quitting smoking, this doesn't mean that quitting smoking is not doing any good.

Despite all the confusions over the causality, the most important conclusion is that "smoking cessation does improve overall cardiovascular disease risk, and this is recommended for everyone". Quitting smoking is one of the most important steps in the management of hypertension or any other cardiovascular disease. Without smoking cessation, the antihypertensive drugs are also not very beneficial. They may reduce the blood pressure, but overall effect on coronary heart disease is not satisfactory without smoking cessation. With smoking cessation, the cardiovascular disease risk starts to decline and becomes very low after 3-5 years of quitting.