Morning headache is considered to be a symptom of obstructive sleep apnea syndrome (OSAS). Despite not being as common as excessive daytime sleepiness or unrefreshing sleep, it can similarly impair everyday activities. The aim of the present study was to evaluate the prevalence of and factors associated with morning headaches (MH) among patients referred for polysomnography due to suspected OSAS. This is a retrospective study on 1131 patients who underwent polysomnography between 2013 and 2015. Morning headaches (MH) were reported in 29% of them. In a logistic regression model, a rise in the n probability of MH was associated with female sex (odds ratio, OR, 1.38, 95% confidence interval, CI, 1.08-1.75), history of hypertension (OR 1.25, 95% CI 1.06-1.46), complaint on unrefreshing sleep (OR 1.42, 95% CI 1.19-1.70), choking at night (OR 1.25, 95% CI 1.05-1.49), and fall in total sleep time (OR 0.872 per each hour, 95% CI 0.76-0.99). The risk between MH and apnea-hypopnea index, blood oxygen saturation parameters or arousal index was found to be statistically insignificant. There is a lack of evidence that MH is associated with the severity of OSAS or nocturnal hypoxemia.
Keywords: BMI; OSAS; morning headaches; risk factors of OSAS.