Atherogenic Index of Plasma in Newly Diagnosed Subjects with Obstructive Sleep Apnea: Results from a Single-Center Observational Study

Abstract Purpose Obstructive sleep apnea syndrome (OSA) is known to be associated with cardiovascular diseases, yet the relationship between OSA severity and the atherogenic index of plasma (AIP) remains unclear. This study evaluates cardiometabolic parameters in newly diagnosed OSA patients without documented cardiovascular disease, with a focus on AIP. Methods A cohort of 122 patients examined in the sleep laboratory underwent polysomnography, metabolic profiling and assessment of endothelial function and arterial stiffness. Participants were stratified by OSA severity, and associations between AIP, apnea–hypopnea index (AHI), and other clinical variables were assessed using univariate and multivariable regression analyses. Results In the whole sample of patients, the higher AHI was significantly associated with higher AIP on univariate analysis, but this relationship was not maintained in multivariable regression analysis after taking into account sex, body mass index, and total cholesterol. In men, significant differences between the subgroups with a rising trend across OSA severity was found in neck circumference and systolic blood pressure, while in women in age, augmentation index standardized to a pulse of 75/min, glucose levels, and systolic blood pressure. Conclusion Our study does not confirm a direct association between AIP and OSA severity after adjusting for confounders, but it highlights sex-specific metabolic and cardiovascular differences in OSA patients. Future research should explore whether AIP contributes to cardiovascular risk stratification in OSA, particularly in sex-specific subgroups.