In patients with asthma, obesity status is associated with poor control and high exacerbation rates, which are reversed after bariatric surgery

Background

In asthma, obesity status is associated with poor control and high exacerbation rates. The primary objective was to determine the effect of bariatric surgery (BS) on asthma control and exacerbations.

Methods

Retrospective study with a 3-year cohort of obese patients before and after BS: a baseline period (P0) covering the 12 months before BS and P1 and P2 periods covering the first and second years after BS, respectively. Asthma control was assessed from the use of relievers, and severe exacerbation rates, i.e. use of oral corticosteroids and asthma-related hospitalizations (ARHs). P1 and P2 measures were compared with those of P0. Patients were matched with non-obese patients and compared over P0 using a generalized linear mixed model with random effects.

Results

2601 asthma patients undergoing BS were included. Of these, 2556 patients were matched with 2556 nonobese asthma patients. After BS, the risk of poor control decreased [OR = 0.26 (95 % CI: 0.21–0.32)] together with the mean exacerbation rate, with IRRs of 0.54 (95 % CI: 0.51–0.58) and 0.60 (95 % CI: 0.56–0.64) for P1 and P2, respectively, compared with P0. The incidence risk ratios (IRRs) were of 1.19 (95 % CI: 1.04–1.35) and 1.28 (95 % CI: 1.20–1.37) for poor control and severe exacerbation rates, respectively, in obese vs. nonobese asthma patients.

Conclusion

In patients with asthma, obesity is a major risk factor for poor control and increased exacerbation rates, with both outcomes highly reversible for at least two years following BS.