Low cholesterol level does not protect heart from smoking
NEW YORK, Dec 09 (Reuters Health) -- Low blood cholesterol levels are no protection against the heart risks caused by smoking, according to a study of Korean men.
``A low cholesterol level confers no protective benefit'' against smoking-related cardiovascular disease, write Dr. Sun Ha Jee and colleagues at Yonsei University in Seoul, South Korea, and co-author Dr. Lawrence Appel of Johns Hopkins University, Baltimore, Maryland, in the December 8th issue of The Journal of the American Medical Association.
Experts have known for decades that both smoking and high blood levels of cholesterol are strong contributors to cardiovascular disease. In Western nations, smoking and high-fat, high-cholesterol meals often go hand in hand, raising heart risks in a 'synergistic' way.
But few studies have examined the link between smoking and heart disease in East Asian countries, the researchers note. Jee and his colleagues point out that while nearly three out of every four Korean men smoke, most have low blood cholesterol levels, a factor that might help to counter the negative effects of smoking on the cardiovascular system.
To test this theory, they examined the blood cholesterol levels, smoking patterns, and health histories of over 100,000 middle-aged Korean men assessed between 1990-1992.
As expected, the authors found that patients who smoked had double the risk for heart disease compared with nonsmokers. Smoking men had a 60% higher risk of cardiovascular disease compared with their nonsmoking peers.
``A low cholesterol level confers no protective benefit against the harmful effects of smoking on cardiovascular disease risk,'' the authors conclude.
The researchers also note that the number of heart disease deaths in Korea rose dramatically in the 1980s and 1990s, with heart disease becoming the leading cause of death in that country in the early 1990s. They suggest that this rise may be due to changes in heart risk factors, ``particularly cigarette smoking.''
In an interview with Reuters Health, Appel said the study ''provides strong evidence that heart disease and stroke occur in people with low cholesterol levels and that smoking has powerful deleterious effects in such individuals.'' His advice? ``If you don't smoke, don't start. If you do smoke, stop.'' SOURCE: The Journal of the American Medical Association 1999;282:2149-2155.