Incidence of Obstructive Sleep Apnea in Elderly Edentulous Patients and the Possible Correlation of Serum Serotonin and Apnea-Hypopnea Index.

Abstract

To estimate the incidence of obstructive sleep apnea (OSA) in elderly edentulous patients (aged 60-65 years) and investigate a correlation of serum serotonin levels with the apnea-hypopnea index (AHI), respiratory effort-related arousal (RERA), and respiratory disturbance index (RDI). 381 elderly completely edentulous patients (307 male, 74 female) aged 60 to 65 years with a history of edentulism of 12 to 15 months, seeking oral rehabilitation at the prosthodontic clinic at Saraswati Dental College & Hospital, Lucknow, India, between January 2014 and January 2016 were enrolled for the present study. After application of the inclusion and exclusion criteria of this study, 183 patients (162 male, 21 female) who were found susceptible, were subjected to the BERLIN questionnaire and Epworth Sleepiness Scale (ESS) to assess sleep disordered breathing (SDB) and then put through all-night polysomnography (PSG). On the basis of AHI, RERA, and RDI scores, 156 patients (143 male, 13 female) who tested positive for OSA were classified according to its intensity. All 156 patients underwent body-mass index (BMI) estimation, cephalometry, and intraoral examination for skeletal and soft tissue profile record. Serum serotonin was estimated from whole blood samples for the 156 OSA and the 27 normal patients. The 156 (147 nonobese, 9 obese) OSA-positive patients were provided with complete dentures and were trained to use the same as a modified mandibular advancement device (MAD) during sleep at night. These patients were kept on a quarterly follow-up for 9 months. Data collected was subjected to statistical analysis, and inferences drawn. The incidence of OSA in elderly edentulous subjects was found to be 32.03% in males and 8.91% in females. A mere 9 out of 156 (5.76%) elderly edentulous OSA patients were found to be obese (Class I) on the basis of BMI estimation. Cephalometry of the patients showed that they had a skeletal class I maxillomandibular relationship. AHI scores of nonobese patients revealed that most of the patients had moderate OSA, followed by mild OSA and severe OSA. Serum serotonin levels ranged from 53 to 83 ng/dL. AHI score of the 9 obese patients were in the moderate to severe range, and their serum serotonin levels were 60 to 70 ng/dL. A correlation between severity of OSA and serum serotonin level was validated in this study. OSA was found to be prevalent in edentulous subjects due to pharyngeal collapse and decreased neuromuscular control. An inverse relationship of serum serotonin levels and AHI scores was established.