Evaluation of acoustic voice characteristics before and after bariatric surgery

Obesity represents one of the most significant global health issues. According to the National Health and Nutrition Examination Survey (NHANES), in the United States alone, during the years 2003–2004, obesity was present in 28.5% of adults aged 20–39, 36.8% of those aged 40–59, and 31.0% of individuals aged 60 and above. Obesity has been associated with numerous diseases such as hypertension, cardiovascular diseases, diabetes, stroke, and obstructive sleep apnea. There is a growing consensus that bariatric surgery currently constitutes the most effective and sustainable clinical treatment for obesity, which has led to a significant increase in the number of bariatric procedures performed in recent years. Bariatric surgery patients undergo numerous dramatic lifestyle changes, and a comprehensive preoperative evaluation conducted by a multidisciplinary team is crucial to prepare them for the many adjustments required for a successful outcome. This study compares the preoperative and postoperative acoustic voice characteristics of patients undergoing bariatric surgery, examining specific vocal parameters. The relationship between voice changes and alterations in weight, upper airway dimensions, and morphology following bariatric surgery was evaluated. The study was conducted with 15 individuals between the ages of 18 and 65 who had no speech or communication disorders. Individuals with a history of dysphonia, recent upper respiratory tract infections, and/or laryngeal manipulation were excluded from the study. Participants with morbid obesity (BMI > 30 kg/m²) who were deemed suitable for surgical intervention after multiple failed dietary treatments were included. After obtaining informed consent, demographic information such as age, weight, and height was recorded, and the GRBAS scale and Voice Handicap Index (VHI) were administered. Participants were then asked to produce vocal sounds in a quiet environment at a comfortable pitch and loudness. In acoustic analysis, parameters such as fundamental frequency (Fo) and cepstral peak prominence (CPP) were assessed, while aerodynamic measurements included maximum phonation time. Voice recordings were evaluated both objectively and subjectively to determine the effectiveness of the program and its impact on vocal parameters.