Smoking, metabolic problem raises heart risk

NEW YORK (Reuters Health) - High rates of tobacco smoking and a condition called metabolic syndrome are combining to increase the risks of heart disease and stroke among older individuals in China, according to a report in the Journal of the American College of Cardiology.

Metabolic syndrome refers to a cluster of risk factors for diabetes and heart disease -- including abdominal obesity, high blood pressure, high blood sugar, low levels of "good" HDL cholesterol and high triglycerides (another type of blood fat). The syndrome is typically diagnosed when a person has three or more of these conditions.

"To the best of our knowledge, this is the first study to report the joint effects of tobacco smoke exposure and metabolic syndrome on cardiovascular risk in a population-based study in China," Dr. Yao He from Chinese PLA General Hospital, Beijing, told Reuters Health.

He and colleagues examined the individual and combined effects of active smoking, secondhand smoke, and metabolic syndrome on the risks of heart disease and stroke in a survey of elderly Chinese in Beijing.

More men than women reported ever having smoked tobacco, the authors report, but more women than men reported secondhand exposure to tobacco smoke.

The rate of metabolic syndrome was 34.8 percent in men and 54.1 percent in women.

Metabolic syndrome was associated with an increased risk of heart disease and stroke, the researchers note, and the risk was higher among former and current smokers than among people who had never smoked.

Further analysis showed that the combined effect of smoking and metabolic syndrome on heart disease and stroke was stronger in women than in men. Moreover, only in women was exposure to secondhand smoke associated with these conditions.

"It is likely that the growing double epidemics of smoking and metabolic syndrome in China will greatly and rapidly increase the burden of cardiovascular disease from traditional risk factors," He said. "Urgent public health measures and clinical practices should be used to prevent the health hazard from the double epidemics."

SOURCE: Journal of the American College of Cardiology, January 27, 2009.