The Atherosclerosis Risk in Communities (ARIC) Study, which has been monitoring individuals in the United States since the late 1980s, provided the researchers with data from 14,344 participants. At the start of the study, participants’ average age was 54.1, and 26.4% of them were Black.

The study classified participants based on their usage of smokeless tobacco and cigarette smoking. It then examined which adults went on to develop PAD by looking at hospitalizations with limb revascularization or PAD diagnostic codes. When sociodemographic and cardiovascular risk factors were taken into account, usage of smokeless tobacco was linked to a two-fold elevated risk for PAD. Only those who were not smoking at the start of the trial saw this increased risk.

Smokeless tobacco users had a diagnosis rate of 4.4 per 1,000 person years while current cigarette smokers had a diagnosis rate of 3.4 per 1,000 person years. When compared to those who had never used smokeless tobacco and weren’t actively smoking, there were only 1.3 occurrences of PAD per 1,000 person years. Significantly, persons who used smokeless tobacco and also smoked cigarettes did not see an incremental increase in risk. This may be because the risk of PAD from cigarette smoking is so great that the risk was not significantly reduced by adding another tobacco exposure.

For the past 30 years, public health initiatives in the US have successfully reduced cigarette smoking, but smokeless tobacco use is rising, with 2.4% of adults using it.

While smokeless tobacco products may not expose people to the noxious effects of combustion, our study shows that they nonetheless have an adverse impact on vascular health. It is important for clinicians to understand these health implications, screen patients for all forms of tobacco and nicotine use, and counsel accordingly,” Dr. Van’t Hof advised. Noting that uncertainty remains about the net benefit versus harm of vaping, he explained that the study did not evaluate e-cigarettes because the baseline ARIC data was collected before they were introduced.