C-reactive protein in children with obstructive sleep apnea and effects of adenotonsillectomy

Abstract

Objective: C-reactive protein (CRP) is an important serum marker of inflammation associated with cardiovascular outcomes. This study aims to evaluate the association between CRP and childhood obstructive sleep apnea (OSA) and clarify the effects of adenotonsillectomy on serum CRP levels in children with OSA. Methods: Children with symptoms suggestive of OSA who underwent an overnight polysomnography were recruited from a tertiary medical center. Their serum CRP levels were measured. For children who underwent adenotonsillectomy for OSA treatment, polysomnography and serum high-sensitivity CRP (hs-CRP) level measurement were conducted after surgery. Results: This study included 326 children (mean age: 7.2 ± 3.0 years; boys: 67%). Children with apnea-hypopnea index (AHI) > 5 events/h had significantly higher hs-CRP levels than children with AHI of 1–5 events/h and AHI < 1 event/h [median (interquartile range): 0.08 (0.03–0.25) vs 0.03 (0.02–0.14) vs 0.04 (0.01–0.10), P < 0.001]. Log-transformed hs-CRP levels were positively associated with log AHI values (r = 0.2, P < 0.001). In multiple linear regression analysis, hs-CRP levels were independently associated with AHI; 101 children with OSA (ie, AHI > 1) underwent adenotonsillectomy. In children with OSA in the study cohort, a significant reduction of hs-CRP levels did not occur after surgery [from 0.07 (0.02–0.22) to 0.08 (0.03–0.17), P = 0.716]. In children with OSA having abnormal hs-CRP levels (ie, CRP > 1 mg/dL), hs-CRP levels significantly decreased after surgery [from 1.87 (1.11–2.78) to 0.20 (0.07–1.04), P = 0.043]. Conclusion: Children with OSA had increased hs-CRP levels. Children with OSA and abnormal hs-CRP levels exhibited significantly reduced hs-CRP levels following adenotonsillectomy.