0585 C-Reactive Protein Improves the Ability to Detect Cardiometabolic Risk in Mild-to-Moderate Sleep Apnea

Abstract Introduction Mild-to-moderate obstructive sleep apnea (OSA) affects 15-40% of the adult general population. However, it remains unclear when and how best to treat mild-to-moderate OSA. It has been shown that mild-to-moderate OSA in general random samples is associated with incident hypertension. 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 insulin resistance (IR). Methods A clinical sample of 148 adults (53.79±12.45) with mild-to-moderate OSA (AHI between 5 and 29 events per hour) underwent 8-hour polysomnography, a clinical history and physical examination, including measures of blood pressure, body mass index (BMI), fasting blood glucose, insulin and CRP plasma levels. Hypertension was defined by previous diagnosis, past or present treatment, or blood pressure ≥140/90. IR was defined by homeostatic model assessment. Individuals with diabetes and/or on diabetes medication were excluded from analyses with IR. All analyses were conducted controlling for age, gender and BMI. Results CRP levels (OR=2.62, 95% CI=1.35-5.04, p=0.004), age (OR=1.75, 95% CI=1.11-2.75, p=0.016), and BMI (OR=2.74, 95% CI=1.20-6.26, p=0.017) were independently associated with greater odds for hypertension, whereas AHI (OR=1.33, 95% CI=0.61-2.92, p=0.477) was not. Additionally, CRP levels (β=0.21; p=0.04) and BMI (β=0.24; p=0.02) were independently associated with higher IR, while AHI (β=-0.03; p=0.75) was not. There was a trend for this association to be stronger in non-obese patients. Conclusion These preliminary findings suggest that including a measure of inflammation improves the ability for clinicians to detect cases of mild-to-moderate OSA with true cardiometabolic risk. CRP may be a simple, easy-to-use biomarker that can improve prognosis assessment and clarify which treatment option is best for patients with mild-to-moderate OSA. Support Department of Psychiatry, Penn State College of Medicine