Secondhand smoke linked to peripheral artery disease in women

Secondhand smoke significantly increased the risk of women developing peripheral artery disease (PAD) in a Chinese study, researchers reported in Circulation: Journal of the American Heart Association. In a population-based study of 1,209 women in Beijing, China, researchers found a 67 percent increased risk of PAD in those exposed to secondhand smoke compared to those who were not exposed. The women were 60 years and older and had never smoked. Of these women, 39.5 percent were exposed to secondhand smoke at home or in the workplace.

Secondhand smoke exposure was defined as exposure to another person's tobacco smoke for at least 15 minutes daily for more than one day every week for at least two years during the past 10 years.

"This is the first study to show the adverse effects of secondhand smoke on peripheral artery disease in women," said Yao He, M.D., Ph.D., the study's lead author and professor of epidemiology at the Chinese PLA General Hospital in Beijing.

Researchers also found the risk of ischemic stroke increased by 56 percent, while the risk of coronary heart disease (CHD) increased by 69 percent compared to those who were never exposed to secondhand smoke.

"This study broadens the finding about the detrimental health effects of passive smoking on heart disease and stroke," said Frank Hu, M.D., Ph.D., the study's senior author and professor of nutrition and epidemiology at the Harvard School of Public Health in Boston, Mass.

Researchers used two different measures to analyze the effects of passive smoking on PAD:

• Signs of intermittent claudication. This is the clinical diagnosis given for muscle pain (ache, cramp, numbness or sense of fatigue), classically in the calf muscle, which occurs during exercise and is relieved by a short period of rest.
• Ankle-brachial index. This is a test that measures the ratio of systolic blood pressure at the ankle and at the arm, then calculates the index for each leg.

In the overall study:

• 431 prevalent cases of CHD, 172 cases of stroke (109 of those had ischemic stroke) and 271 cases of PAD were documented.
• The prevalence of secondhand smoke exposure of 39.5 percent involved 477 individuals.
• The majority, 414 (86.8 percent) were exposed in the home environment and 63 (13.2 percent) were exposed in the workplace.

Hu noted that most studies have shown the adverse effects of both active and passive smoking are not much different in western and Asian populations. Hu suggested that men are likely to have the same deleterious effects from exposure to secondhand smoke as women, although that conclusion cannot be reached from this study.

"Most people in China are unaware of the serious health hazards of passive smoking," Hu said. "It should definitely be discouraged by public health policy."

Source: American Heart Association