Antibiotics linked to increased risk of heart attacks, especially among women

New study shows prolonged use linked to Stroke hazards too

Women who take antibiotics for two months or longer are at increased risk of heart attack or stroke, according to new research. The study, published this week in the European Society of Cardiology, had researchers evaluating the participants - part of the Nurses' Health Study - between 2004 and June 2012.

The team found that women aged 60 or older who took antibiotics for two months or more had the greatest risk of cardiovascular disease, but the long duration of antibiotic use was also associated with an increased risk if taken during middle age (aged 40-59). The researchers studied 36,429 women who took part in the Nurses' Health Study, which has been running in the USA since 1976.

Of the participants, 1,056 developed cardiovascular diseases over the course of the follow-up period of nearly eight years. The researchers categorised them into four groups: those who had never taken antibiotics, those who had taken them for time periods of less than 15 days, 15 days to two months, or for two months or longer.

Antibiotics harm beneficial bacterial cells

According to senior author Lu Qi, a professor at Harvard University, antibiotic use is known to alter the balance of gut microorganisms, which can, in turn, lead to "inflammation and narrowing of the blood vessels, stroke and heart disease,

A possible reason why the use of antibiotics is associated with increased risk for heart attack and stroke is that these medications affect the balance of the microenvironment in the gut.

The first author of the study Dr. Yoriko Heianza says "By investigating the duration of antibiotic use in various stages of adulthood we have found an association between long-term use in middle age and later life and an increased risk of stroke and heart disease during the following eight years".

"As these women grew older they were more likely to need more antibiotics, and sometimes for longer periods of time, which suggests a cumulative effect may be the reason for the stronger link in older age between antibiotic use and cardiovascular disease."

"Our study suggests that antibiotics should be used only when they are absolutely needed. Considering the potentially cumulative adverse effects, the shorter time of antibiotic use the better," he added.

Bottom Line: Women who took antibiotics for longer than two months in middle age had a 28 per cent increased risk compared to women who did not.