Association between ln(FPG/HDL-C) × BMI and self-reported obstructive sleep apnea

Obstructive sleep apnea (OSA) is linked to fasting plasma glucose, high-density lipoprotein cholesterol, and body mass index. However, the association between OSA and the ln[(fasting plasma glucose)/(high-density lipoprotein cholesterol)] × body mass index (FHB) index: calculated as ln(FPG/HDL-C) × BMI: has not been extensively investigated in US adults. This research aims to investigate whether the FHB index is associated with the risk of self-reported OSA symptoms among US adults. The analysis utilized National Health and Nutrition Examination Survey datasets collected during the 2005 to 2008 and 2015 to 2018 survey cycles. Weighted multivariable regression and curve fitting were applied to explore the FHB index-OSA correlation, while subgroup and sensitivity analyses were conducted to evaluate the consistency of this relationship. Among 7414 study subjects, 3694 reported symptoms of OSA. Curve fitting showed a nonlinear positive relationship of the FHB index for OSA risk ( P for nonlinearity <.001), with an identified threshold of 25.84. Below this value, each 1-unit increase in the FHB index was linked to a 5.2% increase in OSA risk (odds ratio [OR] = 1.052; 95% confidence interval [CI]: 1.009–1.096). Above this value, each 1-unit increase was linked to a 2.6% increase (OR = 1.026; 95% CI: 1.022–1.031). When the FHB index was analyzed as a categorical variable, individuals in the third tertile of the FHB index had odds of OSA that were 211.9% higher than those in the first tertile (OR = 3.119; 95% CI: 2.675–3.635). Subgroup and sensitivity analyses confirmed the robustness of this association. This cross-sectional study revealed a nonlinear positive relationship between the FHB index and self-reported OSA among US adults. The FHB index may serve as a novel and convenient candidate marker for identifying individuals at high-risk of OSA, meriting further investigation. However, before considering clinical application, these findings require validation through longitudinal studies.