# Non-Linear Association between Obstructive Sleep Apnea Risk and Lipid Profile: Data from the 2015–2018 National Health and Nutrition Examination Survey

## TL;DR

This study finds a non-linear link between sleep apnea risk and poor lipid levels, with physical activity playing a mediating role.

## Contribution

The study reveals a non-linear association between obstructive sleep apnea risk and lipid profiles, mediated in part by physical activity.

## Key findings

- OSA risk is non-linearly associated with higher TC, LDL-C, and TG, and lower HDL-C.
- Physical activity mediates 16.6-16.7% of the effect of OSA risk on hyperlipidemia and cardiovascular mortality.
- High OSA risk correlates with increased dyslipidemia prevalence.

## Abstract

The relationship between
the multivariable apnea prediction (MAP) index and lipid levels was examined
using a cross-sectional and retrospective study of National Health and Nutrition
Examination Surveys (2015–2018). A total of 3195 participants with MAP scores
were included in the analysis.

The MAP index, an algorithm
leveraging sleep apnea symptom frequency, body mass index (BMI), age, and sex,
estimates the risk of obstructive sleep apnea (OSA). We investigated the
associations between the MAP index and lipid profiles—specifically,
high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), low-density
lipoprotein cholesterol (LDL-C), and triglycerides (TG) —using weighted linear
regression and restricted cubic splines (RCS) analysis. Additionally, mediation
analysis was conducted to explore the potential mediating role of physical
activity on the link between OSA risk, hyperlipidemia, and cardiovascular
mortality.

A non-linear relationship was observed between OSA
severity and lipid profiles, including elevated levels of TC, increased LDL-C,
higher TG, and decreased HDL-C (All p for non-linearity <0.05). The
findings remained consistent across the stratified sensitivity analyses.
Furthermore, physical activity served as a mediator in the association between
the MAP index and both hyperlipidemia and cardiovascular mortality, accounting
for 16.6% and 16.7% of the indirect effects, respectively.

Participants at high risk for OSA demonstrated an increased
prevalence of dyslipidemia. Additionally, engagement in physical activity was
shown to have beneficial effects on lipid metabolism.