Taking antibiotics for longer time raises women’s risk of heart attack, stroke

Women who take antibiotics for two months or longer are at increased risk of heart attack or stroke, according to new research involving 36,429 women in the U.S.

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For the study, published this week in the European Society of Cardiology, researchers studied the participants—part of the Nurses' Health Study—between 2004 and June 2012.

At the start of the study in 2004, the women were age 60 or older and responded to surveys on their use of antibiotics when they were young (ages 20-39), middle-age (ages 40-59) or after age 60. The women continued filling out questionnaires every two years.

During a follow-up of about eight years, researchers noted that 1,056 of the participants developed heart disease. Ultimately, duration of antibiotic use in middle and older adulthood (not young adulthood) showed significant associations with heart disease later in life.

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After adjusting for other factors like major diseases, race, sex, age and diet, researchers found that compared to women who didn’t use antibiotics in late adulthood, those who took them for two months or longer were 32% more likely to develop heart disease. And women who took antibiotics for two months or longer in middle age had a 28% increased risk.

"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," study author Yoriko Heianza of Tulane University said in a statement.

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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," he told the Independent.

Read the full study at academic.oup.com.