Many, many people wind up taking numerous courses of antibiotics at some points in life. Think of recurrent sinus infections or urinary tract infections or other infections. Or some conditions (e.g. dental or skin conditions) are treated with really long courses of antibiotics New research (from 36,429 women participating in the long-running Nurses' Health Study) found that women who take antibiotics over a long period of time during middle-age (40 to 59 years old), but even more so in late adulthood (60 years and over), are at increased risk of heart attack or stroke within the next 8 years.
How increased a risk for cardiovascular diseas? 28% or higher risk (compared to those who didn't take antibiotics)! But looking at the actual numbers it means: Among women who take antibiotics for two months or more in late adulthood, six women per 1,000 would develop a cardiovascular disease, compared to three per 1,000 among women who had not taken antibiotics.
Eight years was the length of the study, so it is unknown if the increased risk persists longer. The authors give a number of possible reasons for these results, but think it might be because antibiotic use results in gut microbial alterations. And the longer the antibiotic use, the more persistent the gut microbiome (microbial community) alterations. Other research studies supports this link (antibiotic use - gut microbe disruptions - increased cardiovascular disease). Another reason to eat in as healthy a manner as possible to feed beneficial gut microbes: a diet rich in fruits, vegetables, whole grains, seeds, and nuts.
From Medical Xpress: Antibiotic use linked to greater risk of heart attack and stroke in women
Women who take antibiotics over a long period of time are at increased risk of heart attack or stroke, according to research carried out in nearly 36,500 women. The study, published in the European Heart Journal today, found that women aged 60 or older who took antibiotics for two months or more had the greatest risk of cardiovascular disease, but long duration of antibiotic use was also associated with an increased risk if taken during middle age (aged 40-59). The researchers could find no increased risk from antibiotic use by younger adults aged between 20-39.
Professor Lu Qi, director of the Tulane University Obesity Research Centre, Tulane University, New Orleans, and adjunct professor of nutrition at Harvard T.C. Chan School of Public Health, Boston, USA, who led the research, says that a possible reason why antibiotic use is linked to an increased risk of cardiovascular disease is because antibiotics alter the balance of the micro-environment in the gut, destroying "good" probiotic bacteria and increasing the prevalence of viruses, bacteria or other micro-organisms that can cause disease.
"Antibiotic use is the most critical factor in altering the balance of microorganisms in the gut. Previous studies have shown a link between alterations in the microbiotic environment of the gut and inflammation and narrowing of the blood vessels, stroke and heart disease," he said.
The researchers studied 36,429 women who took part in the Nurses' Health Study, which has been running in the USA since 1976. The current study looked at data from 2004 to June 2012. In 2004 the women were aged 60 or older, and they were asked about their use of antibiotics when they were young (20-39), middle-aged (40-59) or older (60 and older). 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. During an average follow-up period of nearly eight years, during which time the women continued to complete questionnaires every two years, 1056 participants developed cardiovascular disease.
After adjustments to take account of factors that could affect their results, such as age, race, sex, diet and lifestyle, reasons for antibiotic use, overweight or obesity, other diseases and medication use, the researchers found that women who used antibiotics for periods of two months or longer in late adulthood were 32% more likely to develop cardiovascular disease than women who did not use antibiotics. Women who took antibiotics for longer than two months in middle age had a 28% increased risk compared to women who did not.
These findings mean that among women who take antibiotics for two months or more in late adulthood, six women per 1,000 would develop a cardiovascular disease, compared to three per 1,000 among women who had not taken antibiotics.
The first author of the study is Dr. Yoriko Heianza. a research fellow at Tulane University. She said: "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."
The most common reasons for antibiotic use were respiratory infections, urinary tract infections and dental problems. ... "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."