Bmis Have Different Effects on the Prevalence of OSA in Copd Patients: A Multicenter Cross-sectional Study

Abstract

BackgroundObstructive sleep apnea (OSA) is prevalent in chronic obstructive pulmonary disease (COPD). Underweight and overweight have paradoxical effect on COPD prognosis, while obesity is a risk factor for OSA. We aimed to examine the association between BMIs and OSA risk in COPD patients. MethodsThis cross-section study included 1637 COPD subjects in the final analysis. BMI was classified into different groups. OSA was defined as varying severity by AHI. The associations between BMIs and risks of diverse severity of OSA were examined. ResultsFor varying severity of OSA, obesity associated with higher risk, while normal weight group associated with lower risk; overweight had no differences and underweight group had lower risk of moderate-to-severe OSA. Compared with normal weight, for OSA, the overweight group showed a trend of high risk whereas the underweight group indicated a higher risk (OR 1.424, 95% CI 1.015-1.988) (multivariable adjusted). BMI exhibited a J-shaped association with OSA; the risk for OSA was relatively flat at BMIs of 20-24 kg/m2 and above or below the risk increased (P for non-linearity 0.0057); for severe OSA, the plot depicted a S-shaped relation, the risk reached the lowest around 24 kg/m2 and then increased thereafter (P for non-linearity 0.0200). ConclusionsIn COPD population, for various severity of OSA, obesity is a firmly risk factor, overweight not influence the risk, while normal weight associate with lower risk; compared with normal weight, underweight increased the risk for OSA; BMI had a J-shaped association with OSA and a S-shaped with severe OSA.