C-Reactive Protein as a Predictor of Cardiovascular Events and Mortality in Obstructive Sleep Apnea: A Propensity-Matched Analysis Using the TriNetX Research Network

INTRODUCTION: Obstructive sleep apnea (OSA) increases cardiovascular disease risk through systemic inflammation, particularly through elevated C-reactive protein (CRP). This study investigated whether CRP stratification predicts mortality and cardiovascular events in OSA patients. METHODS: We conducted a retrospective cohort analysis using the TriNetX Research Network, encompassing electronic health records from 130 healthcare institutions. Adults (ages 18-90 years) with OSA were stratified by CRP concentration: elevated (≥ 3.0 mg/L) versus low (≤ 2.9 mg/L). After propensity score matching for demographics and comorbidities, 240,727 participants per cohort were followed for five years. Primary outcome was all-cause mortality; secondary outcomes included cardiovascular events, arrhythmias, and acute kidney injury. RESULTS: Elevated CRP was associated with significantly higher all-cause mortality (11.3% versus 7.0%; HR 1.695, 95% CI 1.662-1.727; p < 0.001). The elevated CRP group demonstrated heightened cardiovascular risk: cardiogenic shock (1.0% versus 0.5%; HR 2.003), heart failure (9.8% versus 6.5%; HR 1.594), pulmonary hypertension (4.9% versus 3.4%; HR 1.508), and acute kidney injury (11.0% versus 6.4%; HR 1.825), all p < 0.001. Arrhythmic complications were also increased: atrial fibrillation/flutter (6.3% versus 4.8%; HR 1.372) and ventricular tachycardia (2.3% versus 1.8%; HR 1.388), both p < 0.001. CONCLUSION: Elevated CRP constitutes a robust predictor of mortality and cardiovascular morbidity in OSA populations. Assessment of inflammatory biomarkers may enhance risk stratification, informing intensified monitoring and targeted therapeutic interventions.