C‐reactive protein improves the ability to detect cardiometabolic risk in mild‐to‐moderate obstructive sleep apnea

Obstructive sleep apnea (OSA), particularly in the mild‐to‐moderate range, affects up to 40% of the adult general population. While it is clear that treatment should be pursued in severe cases of OSA, when and how to best treat OSA in the mild‐to‐moderate range remains complicated, despite its high prevalence. The aim of this study was to compare the relative utility of apnea/hypopnea index (AHI) versus a biomarker of inflammation, C‐reactive protein (CRP), in identifying the presence and severity of hypertension and hyperglycemia. Middle‐aged (n = 60) adults with mild‐to‐moderate OSA (AHI between 5 and 29 events per hour) underwent 8‐h polysomnography, a physical examination including measures of blood pressure and body mass index, and a fasting morning blood draw for glucose and CRP. CRP levels were associated with greater odds for having hypertension and hyperglycemia compared to AHI. Receiver‐operating characteristics (ROC) curves revealed that adding CRP to standard clinical factors (age, sex, and BMI) yielded moderately good to strong risk models for the disorders (AUC = 0.721 and AUC = 0.813, respectively). These preliminary findings suggest that including a measure of CRP improves the ability for clinicians to detect cases of mild‐to‐moderate OSA with true cardiometabolic risk, with implications in improving prognosis and treatment within this clinically gray area.