Using antibiotics for two months or longer may be linked to an increase in a woman’s risk for cardiovascular disease.
The finding, published in the European Heart Journal, applied to women who used the drugs when they were 40 and older.
Researchers used data on 36,429 women free of cardiovascular disease at the start of the study who were participating in a continuing long-term health study. Beginning in 2004, the women reported their use of antibiotics.
Over seven years of follow-up, there were 1,056 cases of cardiovascular disease. Compared with women who never used them, women who used antibiotics for two months or longer during their 40s and 50s had a 28 percent increased risk for cardiovascular disease, and women over 60 who used them that long had a 32 percent increased risk.
The study controlled for family history of heart attack, body mass index, hypertension, the use of other medications and other factors.
“It’s difficult to distinguish the effect of the antibiotic on cardiovascular disease from the effect of the disease for which the antibiotic was taken, and that’s a potential limitation of the study,” said the lead author, Lu Qi, now a professor of epidemiology at Tulane University. “But that we are seeing the effect of the disease instead of the antibiotic is unlikely, because we see the effect in so many different diseases where antibiotics are used.”