DYSPHAGIA-RELATED QUALITY OF LIFE IN OCULOPHARYNGEAL MUSCULAR DYSTROPHY: PSYCHOMETRIC PROPERTIES OF THE SWAL-QOL INSTRUMENT

Introduction: The Swallowing Quality of Life instrument (SWAL-QOL) is a patient-reported outcome measure of swallowing-related quality of life (SR-QoL). Its psychometric properties in oculopharyngeal muscular dystrophy (OPMD) are not known. Methods: We administered the SWAL-QOL to U. S. OPMD Registry participants. We described SR-QoL profiles and assessed reliability and validity. Results: The mean composite score in 113 individuals with OPMD was 54.4620.7, indicating moderate impairment. Severe impairments were observed in eating duration, burden, and fatigue scales. Internal consistency reliability of all scales was found to be satisfactory, and 9 of 10 scales demonstrated adequate test-retest reliability. Data confirmed 86% of hypotheses, supporting construct validity. The SWAL-QOL limitations in OPMD include: floor/ceiling effects in 7 of 10 scales and low specificity of sleep, fatigue, and communication scales for dysphagia. Conclusions: SR-QoL is reduced in OPMD. Given several limitations of the SWALQOL, development of an improved dysphagia-specific QoL instrument for OPMD is warranted.