Publication:

Prevalence of hypothyroidism in obstructive sleep apnea

Background Patients with OSA usually present with complaints of excessive daytime sleepiness, un-refreshing sleep, fatigue or insomnia. Earlier studies have suggested an influence on hypothyroidism whose incidence differed in different geographical areas and between races. This study was conducted to identify the prevalence of hypothyroidism in obstructive sleep apnea in our area.

Methods Polysomnography was conducted on all patients referred for sleep apnea test after performing the regular clinical and physical examination. Blood tests were done to diagnose hypothyroidism. AHI and the Epworth Sleepiness scale was done for assessment for daytime sleep patterns. BMI was calculated for all patients.

Results There was a predominance of males with OSA than females, though the incidence of hypothyroid was greater in females. 36 patients were found to be hypothyroid of which, 27 were previously detected cases and on medication. Only 9 patients (2.4%) were newly diagnosed cases. Male patients with hypothyroid were heavier in weight than the females or men without hypothyroid, had higher ESS, AHI and desaturation Index and low sleep efficiency and arousal indexConclusions: There were more males than females having sleep apnea although the hypothyroidism was more common in females than in males. The prevalence of hypothyroidism was not significant than the normal population. Therefore, the detection of TSH in sleep apnea cases should be considered only if there are other risk factors and indications like obesity, persistent sleepiness despite therapy.