Asthma linked to elevated obesity risk
Individuals with asthma may have a tendency to develop obesity, with a higher risk observed among those with adult-onset asthma, according to findings of the European Community Respiratory Health Survey (ECRHS) presented at the recent international congress of the European Respiratory Society (ERS 2018).
“By following a large number of study participants over 2 decades, we have been able to observe how having asthma increases a person’s risk of going on to become obese, especially if their asthma begins in adulthood or if they have asthma but no allergies,” said study author Dr Subhabrata Moitra, an ERS research fellow at the Barcelona Institute for Global Health (ISGlobal) in Barcelona, Spain.
The study population comprised 8,618 individuals from 12 countries who were not obese at baseline (BMI ≤30 kg/m2 at ECRHS-I) who were followed up at least once, either at the 10-year (ECRHS-II) or 20-year follow-up (ECRHS-III). Participants were determined as having asthma if they were ever diagnosed with asthma, had experienced an asthma attack, or had woken up due to a shortness of breath attack in the previous 12 months, or were currently on asthma medication.
Individuals who had asthma at baseline had a higher risk of being obese at 10 years compared with those without asthma (10.2 percent vs 7.7 percent, adjusted relative risk [adjRR], 1.26, 95 percent confidence interval [CI], 1.03–1.55). [ERS 2018, abstract OA297]
The highest risk for obesity was observed among individuals who had developed asthma in adulthood (RR, 1.37, 95 percent CI, 1.01–1.86) compared with individuals who had developed asthma in childhood (RR, 1.13, 95 percent CI, 0.83–1.53).
The risk for obesity at 10 years was also elevated among individuals with non-atopic asthma at baseline (RR, 1.47, 95 percent CI, 1.15–1.86).
“We already know that obesity can be a trigger for asthma, perhaps via a physiological, metabolic, or inflammatory change. Until now there has been very little research on whether the reverse is true – whether asthma can lead to obesity,” said Moitra.
“Our findings suggest the relationship between the two conditions is more complicated than we previously realized. It’s important that we do more work to pick this apart. For example, we do not know why having asthma increases the risk of developing obesity or whether different asthma treatments have any effect on this risk,” added Moitra.
“With the right medication, many people with asthma gain good control of their symptoms. However, there is no cure for asthma and there is still a lot we do not know about its causes and its effects on the rest of the body,” said Professor Guy Brusselle from Ghent University in Ghent, Belgium and Chair of the ERS Science Council, who was not involved in the study.
“This research is an important step in helping us untangle the relationship between obesity and asthma but it also raises new questions about why the two are linked and what can be done to help patients,” he said.