Severe Obstructive Sleep Apnea Is Associated with Cholesterol Target Non-Attainment in Patients Undergoing Cardiac Surgery: A Secondary Analysis of a Prospective Observational Cohort

Background: Obstructive sleep apnea (OSA) has been associated with adverse cardiometabolic profiles, but its relationship with cholesterol target attainment in patients receiving lipid-lowering therapy remains incompletely characterized. We investigated the association between severe OSA and non-attainment of predefined cholesterol thresholds in patients undergoing elective cardiac surgery. Methods: This secondary analysis included 142 adults from a prospectively assembled observational cohort. Participants underwent in-hospital preoperative Type III cardiorespiratory polygraphy, fasting lipid assessment, and documentation of lipid-lowering therapy. Severe OSA was defined as an apnea–hypopnea index ≥30 events/h. The primary outcome was non-high-density lipoprotein cholesterol (non-HDL-C) ≥ 100 mg/dL. Multivariable models were adjusted for age, sex, body mass index, diabetes mellitus, high-intensity statin therapy, and non-statin lipid-lowering therapy. Results: Severe OSA was associated with higher odds of non-HDL-C ≥ 100 mg/dL (adjusted odds ratio [OR] 3.49, 95% confidence interval [CI] 1.56–7.78; p = 0.002), LDL-C ≥ 55 mg/dL (OR 2.93, 95% CI 1.18–7.29; p = 0.021), and LDL-C ≥ 70 mg/dL (OR 2.30, 95% CI 1.03–5.12; p = 0.041). In contrast, associations with continuous LDL-C (p = 0.113) and non-HDL-C (p = 0.100) concentrations were not statistically significant. No significant associations were observed for triglyceride-related or lipid-derived outcomes. The primary association with non-HDL-C ≥ 100 mg/dL remained significant in the analysis restricted to statin-treated patients. Conclusions: Severe OSA was associated with non-attainment of predefined cholesterol thresholds in this cardiac surgical cohort, with the strongest and most consistent association observed for non-HDL-C ≥ 100 mg/dL. These findings identify an association with categorical cholesterol target non-attainment but do not establish treatment failure, causality, or a generalized increase in cholesterol concentrations.