The old saying, “An apple a day, keeps the doctor away” could be very much replaced by a new one, “An aspirin a day, keeps asthma away,” according to researchers at Birgham and Women’s Hospital and Harvard Medical School in Boston.

The study followed 39,876 women aged 45 and older who had never suffered from asthma before. About 18,652 women were assigned to a daily dose of 100 mg aspirin while 18,618 to placebo. The women were followed for 10 years, during which there were 872 new cases of asthma in the aspirin group and 963 in the placebo group, which meant that taking small amounts of aspirin could cut a woman’s risk of developing asthma by a 10th, Dr. Tobias Kurth, Sc.D. and colleagues wrote in their study.

"The effect of aspirin on adult-onset asthma was not significantly modified by age, smoking status, exercise levels, postmenopausal hormone use or randomized vitamin E assignment," Dr. Kurth added.

However, aspirin was found to have no preventive effect on women classed as clinically obese.

Dr. Kurth also added that the research was still not enough to recommend taking aspirin regularly. Before public health recommendations are made, he said, the findings should be tested in specifically designed trials.

The incidence of asthma is on the increase with doctors blaming obesity, dietary factors, exposure to antigens and environmental factors for it. However, the higher incidence coincides with a decreased use of aspirin as people have switched to other over-the-counter pain relievers or have avoided aspirin use in children due to concern about Reyes syndrome.

This is not the first study to link the use of aspirin to a small risk of developing asthma. Previous studies in male doctors showed that aspirin cut the risks of asthma by 22 percent, although the dose was much higher – 325 mg every other day.

The study supported by the National Institute of Health and the National Cancer Institute, was published online by the British Medical Journal ahead of print in Thorax.