A new study led by researchers at the Johns Hopkins Bloomberg School of Public Health found that cigarette smoking boosts the risk of peripheral artery disease, and this elevated risk can persist up to 30 years after smoking cessation. The study also found that the link between smoking and peripheral artery disease was even stronger than that for coronary heart disease and stroke.
The study found that compared with never-smokers, those who smoked for more than 40 pack-years had roughly four times more risk for peripheral artery disease, versus 2.1 times and 1.8 times more risk for coronary heart disease and stroke, respectively. A pack-year is a parameter of smoking: 10 pack-years can mean 1 pack per day for 10 years or 2 packs per day for 5 years or some other combination.
Similarly, participants who reported currently smoking more than a pack per day had a relative increased risk—5.4 times more for peripheral artery disease versus 2.4 for coronary heart disease and 1.9 for stroke—compared to those who had never smoked.
The study, published July 22 in the Journal of the American College of Cardiology, is the first comprehensive comparison, in a large population moving through time, of the smoking-elevated risks of peripheral artery disease, coronary heart disease, and stroke. The analysis was based on a sample of 13,355 Atherosclerosis Risk in Communities (ARIC) cohort participants, including 3,323 current smokers, and 4,185 former smokers, who were tracked for a median period of 26 years.
The effect of smoking on peripheral artery disease risk was not just stronger; it was also longer lasting. Only after 30 years of smoking cessation did the peripheral artery disease risk for former smokers return to the baseline level seen in never-smokers. By comparison, coronary heart disease risk took about 20 years to return to baseline after smoking cessation.
The good news from the analysis is that quitting smoking appeared to bring a meaningful drop in peripheral artery disease risk fairly quickly.
Overall, the results suggest that public health campaigns against smoking should include reference to the elevated peripheral artery disease risk and should emphasize how long it takes to eliminate that risk.
