Light smoking may increase sudden cardiac death risk in women


Even women who are are considered light-to-moderate smokers have a significantly increased risk of sudden cardiac death, new research suggests. But, quitting for less than five years may help them lower that risk by quite a bit.

New research published on Dec. 11 in Circulation: Arrhythmia & Electrophysiology, an American Heart Association Journal, showed that women who smoked one to 14 cigarettes a day were twice as likely to die from their heart ceasing to function. The longer a woman smoked, the higher their risk.

"Cigarette smoking is a known risk factor for sudden cardiac death, but until now, we didn't know how the quantity and duration of smoking effected the risk among apparently healthy women, nor did we have long-term follow-up," study author Dr. Roopinder K. Sandhu, a cardiac electrophysiologist at the University of Alberta's Mazankowski Heart Institute in Edmonton, Alberta, Canada, said in a press release.

Sudden cardiac death (SCD) is an immediate cessation of heart function, and is the largest natural cause of death in the U.S. According to the Cleveland Clinic, about about 325,000 adults die from it in the United States each year. SCD normally happens to adults in their mid-30s to mid-40s, and affects two times the number of men than it does women.

SCD occurs when something goes wrong with the electrical system powering the heart, causing the heart to function abnormally. The heart speeds up and the ventricles start opening and closing rapidly, stopping blood from being delivered around the body. When blood stops being delivered to the brain, a person loses consciousness and could die unless they receive emergency medical care. SCD is not to be confused with a heart attack, which happens when there is something blocking one or more of the coronary or heart arteries.

SCD is also the first sign of heart disease in women, which normally means they have to take measures to prevent any further problems. Stopping smoking is something then can do to help prolong their lives.

Researchers looked at more than 101,000 healthy women in the Nurses' Health Study, which has been surveying women since 1976. They used records that could be traced back to 1980 with about 30 years of follow-up with each patient. Most of the subjects were white and on average started smoking during their late teens. They ranged in age from 30 to 55 years old at the beginning of the study. In total, 351 died during the study of sudden cardiac death.

Besides the light-to-moderate smokers having double the risk of SCD, for each five years of a woman remained a smoker, their risk went up by 8 percent, the study showed. Heavy smokers who smoked 25 or more cigarettes a day had three times the risk for SCD compared to non-smoking women.

Women who had no history of heart disease, cancer or stroke who were smokers were 2.5 times more likely to have and SCD than women who never smoked. For women with heart disease, those who stopped smoking for 15 to 20 years dropped their risk to the same as a person who was a non-smoker with heart disease. Those who stopped smoking and did not have heart disease lowered their SCD risk significantly in less than five years.

The study shows that even modest levels of smoking can increase the risk of sudden cardiac death," Dr. Nieca Goldberg, medical director of the women's heart program at New York University's Langone Medical Center and spokesperson for the American Heart Association, said to WebMD. "People should know that just one cigarette is too much."

Ellen Mason, senior cardiac nurse at the British Heart Foundation, added to the BBC that this study shows that smoking a few cigarettes could affect you negatively in the future.

"As we approach the new year, many of us will be making resolutions and giving up smoking will be top of the list for lots of people," she said. "If you're thinking of quitting and need a nudge, this research adds to the wealth of evidence that stopping smoking is the single best thing you can do for your heart health."