Does short- and long-term exposure to air pollution affect the risk of obstructive sleep apnea? A systematic review...

The contribution of air pollution to obstructive sleep apnea (OSA) remains unclear. This systematic review and meta-analysis evaluated the impact of air pollution across different exposure windows on OSA and examined effect modifiers. Pubmed, Web of Science, and Embase were searched from inception to September 2024. Meta-analyses synthesized risk estimates using fixed- or random-effects models with I² heterogeneity assessment. Certainty of evidence was assessed using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) approach. Of 5196 potential papers, 20 studies were included, with 13 eligible for meta-analysis. High-certainty evidence indicated that each 10 μg/m³ increase in short- and long-term PM_2.5 exposure was associated with a 2.25 % (95 % CI: 1.10 to 3.41) and 13.33 % (95 % CI: 9.85 to 16.80) increase in apnea-hypopnea index (AHI), respectively. For NO₂, each 10 ppb increase in short- and long-term exposure was associated with a 2.92 % (95 % CI: 1.29 to 4.54) and 8.93 % (95 % CI: 2.06 to 15.79) increase in AHI, with high- and moderate-certainty evidence, respectively. Medium-term PM_2.5 and NO₂ exposure were also associated with AHI, although with low certainty. No significant associations were observed for PM₁₀ and O₃. Exposure to PM_2.5 and NO₂, but not PM₁₀ or O₃, was associated with OSA severity.