Association between atherogenic index of plasma and the risk of obstructive sleep apnea in korean adults who admitted to the sleep clinic

Objective: Atherogenic index of plasma (AIP) is closely related to insulin resistance, which is a major characteristics of obstructive sleep apnea (OSA). However, data on the association between AIP and OSA has been limited. This study evaluated the association of AIP with OSA. Methods: AIP was assessed in 180 consecutive Korean adults with suspected OSA who admitted to the sleep clinic between 2010 and 2012. OSA was defined as the occurrence of more than 5 apnea-hypopnea index (AHI) events/h. All participants were divided into three groups according to the AIP tertiles, which were determined by the log of (triglyceride/high-density lipoprotein cholesterol). Results: The prevalence of OSA increased [group I (lowest): 73.8%; group II: 86.4%; group III (highest): 91.7%] as increasing AIP tertiles (p=0.022). AIP had a positive correlation with AHI (r=0.210; p=0.005). In univariate linear regression analysis, AIP (per 0.1-unit increase) was significantly related to AHI (β=2.460; p=0.005). Univariate logistic regression analysis showed that AIP was associated with an increased risk of OSA [odds ratio (OR): 1.450; 95% confidence interval (CI): 1.179-1.785; p<0.001]. However, this association was attenuated after adjusting for multiple risk factors including age, male sex, alcohol consumption, obesity, and smoking (OR: 1.252; 95% CI: 0.995-1.575; p=0.055). Conclusion: Despite a significant correlation of AIP with AHI, AIP was not an independent predictive marker for OSA beyond multiple risk factors. Further investigation with larger sample size might be necessary.