Sleep apnoea syndrome in Ramathibodi Hospital: Clinical and polysomnographic baseline data

Abstract

Objective: The aim of this study was to determine clinical and baseline polysomnographic data on obstructive sleep apnoea (OSA) in Thai patients. This prospective study was performed at the Sleep Laboratory Center, Ramathibodi Hospital, Mahidol University, Thailand. Methodology: Ninety adult cases clinically suspected of having OSA were studied. The study included clinical, blood chemistry, electrocardiogram, chest radiograph, arterial blood gas, spirometry and full night polysomnography. Results: Fifty-nine cases (65.6%) out of a total of 90 cases had an abnormal apnoea (i.e. apnoea index (AI) of 5 or more). The incidence of upper airway abnormality among cases with AI of 5 or more was 79.7% (47/59 cases). Among 59 patients with abnormal AI, associated medical problems comprised hypertension (n=22), obesity hypoventilation (n=9), hypothyroidism (n=4), chronic airflow obstruction (n=4), diabetes mellitus (n=3) and chronic renal failure (n=1). Obstructive sleep apnoea was present in all 59 cases. Central apnoea and mixed apnoea were rare. Conclusion: Symptoms and signs suggestive of OSA can lead to a high detection rate and confirmation of OSA by polysomnography. The OSA characteristics of Thai patients were similar to the patients in the Western world.