Impact of smoking on obstructive sleep apnea: a retrospective study

Obstructive sleep apnea (OSA) has several well-established risk factors. Smoking has been documented as a risk factor for several comorbidities associated with OSA. However, its specific contribution to the severity of OSA and its potential as an independent risk factor require further investigation. In this study, we have evaluated the association between smoking behavior and the severity of OSA and have examined the related sleep parameters and comorbidities. A retrospective analysis was conducted on 567 patients who underwent diagnostic polysomnography. Participants were grouped by OSA severity and smoking status (non-smokers, ex-smokers, and current smokers). Demographic and clinical characteristics, comorbidities, and sleep-related indices were compared across groups. Logistic regression analyses were used to identify predictors of severe OSA. Current and ex-smokers had significantly higher apnea-hypopnea index values (p=0.033), more oxygen desaturation, and lower sleep efficiency (p=0.021) compared to non-smokers. Psychiatric comorbidities and higher Mallampati scores were also more prevalent in the smokers' group. Smokers showed a 1.98 times higher risk of severe OSA as compared to non-smokers in univariate analysis (odds ratio=1.98; p=0.036) but were not retained as an independent risk factor in the multivariate model. Ex-smokers continued to show worse sleep parameters than non-smokers, indicating possible long-term effects of tobacco exposure. These results highlight the need for comprehensive management strategies that address both respiratory and systemic impacts in OSA patients with a smoking history.