Among adult asthmatics who have longstanding disease and using oral corticosteroids, there appears to be an increased risk of developing obesity
Adult asthmatics and, in particular individuals who have had the disease for a long period of time and use of oral corticosteroids, have been found to have a small, but significantly increased risk of developing obesity compared with those without the disease. This was the main finding of a study by researchers from the Division of Pulmonary Medicine, Department of Medicine, Faculty of Medicine & Dentistry, University of Alberta, Canada.
Data for 2016 shows that more than 1.9 billion adults were overweight and, of these, over 650 million were obese. It has also been found that while obese people report more incident asthma, it is not clear whether this represents reactivation of previously diagnosed asthma or the onset of new cases. In terms of, data for children are much clearer with one study finding that among asthmatics, there is a 51% increased risk of developing obesity during childhood and adolescence compared to children without asthma.
Since the relationship between asthma and obesity in adults remains unclear, researchers in the present study, the quest to investigate the occurrence of obesity due to asthma among participants in the European Community Respiratory Health Survey (ECRHS) over 2 periods of 10 years, which were labeled ECRHS-II and ECRHS-III. ECRHS-I began in 1990 and recruited over 18,000 participants and had two follow-up periods at approximately 10-year intervals. The researchers excluded those with a diagnosis of obesity at baseline and then classified individuals as either having ‘no asthma’ or ‘current asthma’. Additional data on the duration of asthma, treatments used and the presence or absence of atopy (based on serum levels of IgE to common allergens) was also collected.
Adult asthmatics and the risk of obesity
The research team included 7576 participants with a baseline mean age of 34 years (51.5% female) in ECRHS I-II and 4976 participants (mean age 42, 51.3% female) in ECRHS-II-III.
The risk of developing obesity was higher among asthmatics compared to those without the condition (relative risk, RR = 1.22, 95% CI 1.07 – 1.38). Furthermore, this risk was also higher among those without atopy (RR = 1.47), for individuals who had asthma for longer than 20 years (RR = 1.32, 95% CI 1.10 – 1.59) and for those using oral corticosteroids (RR = 1.99, 95% CI 1.26 – 3.15). In subgroup analysis, smokers also had a higher risk of becoming obese compared to non-smokers (RR = 1.46).
The authors concluded that adult asthmatics were at a greater risk of developing obesity in later life, especially those with longstanding disease, who were using oral corticosteroids and had non-atopic asthma.
Moitra S et al. Long-term effect of asthma on the development of obesity among adults: an international cohort study, ECRHS Thorax 2022