Simple predictors of uvulopalatopharyngoplasty outcome in the treatment of obstructive sleep apnea

Study objective: Our objective was to determine whether baseline polysomnography, cephalometry, and anthropometry data could predict uvulopalatopharyngoplasty (UPPP) success or failure. Design: We retrospectively reviewed polysomnography, cephalometry, and anthropometry data from patients who underwent UPPP for obstructive sleep apnea (OSA). Setting: A university medical center. Patients: OSA was diagnosed by polysomnography in 46 patients who underwent UPPP surgery for their sleep disorder. Interventions: UPPP surgery with/or without tonsillectomy. Measurements and results: The mean patient age was 43 years, and the mean body mass index was 32.5 kg/m(2). The mean presurgical apnea-hypopnea index (AHI) was 45, and the mean baseline nadir oxygen saturation was 81%. Successful surgery was defined as a reduction in AHI to < 10 or to < 20 with a 50% reduction from the patient's baseline AHI. Of the 46 patients, 16 were successfully treated and 30 did not respond to surgical treatment. A mandibular-hyoid distance (MP-H) > 20 mm was found to be significantly (p = 0.05) predictive of failure of UPPP. When stepwise regression analysis was performed utilizing postsurgical AHI as the dependent variable and presurgical AHI, age, body mass index, baseline nadir O-2 saturation, and five cephalometric measurements as independent variables, MP-H distance significantly (r = 0.524; p = 0.01) correlated positively with postsurgical AHI, The distance between the superior point of a line-constructed plane of the sphenoidale (parallel to Frankfort horizontal) and a point at the intersection of the palatal plane perpendicular to the hyoid correlated negatively with postsurgical AHI (r = 0.586; p = 0.05). By creating a logistic model of this data, an MP-H distance < 21 mm, an angle created by point A to the nasion to point B < 3 degrees, and the presence of a baseline AHI < 38 enhanced the predictability of UPPP success. Conclusions: The presence of a baseline AHI < 38 and an MP-H less than or equal to 20 mm, and the absence of retrognathia are predictors of improvement after UPPP, Based on these findings, we would advocate the continued evaluation of cephalometric measurements and careful consideration of surgical treatment options for OSA.