A study with more than 8,700 participants from 11 European countries and Australia concluded that adults with asthma are more likely to become obese later in life. The research, conducted by the Barcelona Institute of Global Health (ISGlobal), a center supported by the “la Caixa” Foundation, also showed the the risk is higher in non-allergic asthma patients, those who have had the disease for a long time or those who are being treated with corticosteroids. These results were Posted in Thorax.
“Several studies have shown that asthma and obesity share some common socioeconomic, behavioral and environmental risk factors that can lead to the development of both diseases. Some previous research has focused on the mechanisms by which obesity might lead to asthma, but the inverse relationship hadn’t received much attention until recently,” says Subhabrata Moitrawho conducted this research at ISGlobal and is now a researcher at the University of Alberta.
The researchers used data from the European Community Respiratory Health Survey Cohort Study (ECRHS), collected in three waves between 1990 and 2014 and with follow-up visits at approximately 10-year intervals. The different waves collected data from questionnaires, lung function tests and measurements taken to determine participants’ body mass index and asthma status and characteristics.
Between the first and second follow-up, 14.6% of non-asthmatic participants developed obesity, while the percentage increased to 16.9% in asthmatic participants. The difference between the two groups became more evident when the research team translated it into a relative risk who took into consideration the role of other factors such as asthma and smoking, and saw that asthma had a 21% increase in obesity risk compared to non-asthmatic participants.
Participants with asthma with longer disease duration had a 32% higher risk of obesity than those with a shorter duration and those with non-allergic asthma had a 47% increased risk than those with allergic asthma. Participants who treat respiratory disease with corticosteroids showed a 99% higher risk obesity compared to those who did not use this treatment, which had already been associated with abnormal weight gain in previous research.
“A potential explanation for asthma-associated weight gain could be reduced physical activity in asthma patients. However, our results do not support this hypothesis, since physical activity levels in our study did not affect the observed association,” says Judith Garcia-Aymerichhead of the Non-Communicable Diseases and Environment Program at ISGlobal and lead author of the study. “Apart from the mechanisms, which are still unknown, our results have implications for the clinical management of adults with asthma,” she adds.
Unlike a previous study that found this association between asthma and weight gain only in women, in this case there was no gender difference. Another previous study had found an association between asthma in children and obesity after a 10-year follow-up, but this is the first known study to show a similar association in adults regardless of gender.
The study was conducted in Australia, Belgium, Estonia, France, Germany, Iceland, Italy, Norway, Spain, Sweden, Switzerland and the UK.