Association of Air Pollution with Risk and Severity of Obstructive Sleep Apnea: A Systematic Review and Meta-Analysis

Background Obstructive Sleep Apnea (OSA) is a significant health concern characterized by recurrent upper airway blockages during sleep, causing various health issues. There's growing evidence of a link between air pollution and OSA, though research results have been inconsistent. This systematic review and meta-analysis aims to consolidate and examine data on the relationship between air pollution and OSA's risk and severity. Methods A literature search across PubMed, EMBASE, and Web of Science was conducted until January 10, 2024. The selection criteria targeted studies involving OSA participants or those at risk, with quantitative air pollution assessments. The Nested Knowledge software facilitated screening and data extraction, while the Newcastle-Ottawa Scale was used for quality assessment. Meta-analyses, utilizing random-effects models, computed pooled odds ratios (ORs) for the OSA risk associated with PM2.5 and NO2 exposure, analyzed using R software version 4.3. Results The systematic review included twelve studies, four of which were analyzed in the meta-analysis. The meta-analysis revealed diverse results on the association of PM2.5 and NO2 with OSA risk. PM2.5 exposure showed a pooled OR of 0.987 (95% CI: 0.836 to 1.138), indicating no substantial overall impact on OSA risk. Conversely, NO2 exposure was linked to a pooled OR of 1.095 (95% CI: 0.920 to 1.270), a non-significant increase in risk. Many studies found a relationship between air pollution exposure and elevated Apnea-Hypopnea Index (AHI) levels, indicating a relationship between air pollution and OSA severity. Conclusion The findings suggest air pollutants, especially NO2, might play a role in worsening OSA risk and severity, but the evidence isn't definitive. This highlights the variability of different pollutants' effects and the necessity for more research. Understanding these links is vital for shaping public health policies and clinical approaches to address OSA amidst high air pollution.