Radiation-induced Dysphagia: Intervention and Assessment Tools for Head and Neck Cancer

Abstract

Abstract The aim of the thesis was to evaluate the effect of two interventions to prevent or reduce complications of radiation-induced swallowing and mouth opening difficulties among HNC patients. An additional aim was to introduce a valid and reliable tool for assessment of swallowing difficulties among HNC, by translating and validating a Swedish version. Study I and II is based on an RCT evaluating the effect of the head-lift exercise (HLE) on swallowing function assessed by flexible endoscopic evaluation of swallowing (FEES) after 8 weeks of intervention. No convincing effect was found of the HLE on swallowing function assessed by FEES. In study II the effect of the HLE was measured by general and dysphagia-specific health-related quality of life instruments up to 12 months after intervention. No effect of the HLE could be detected, as there were no statistically significant differences attributable be-tween the groups at any follow-up. In study III, the Dynamic Imaging and Grading Assessment Tool for FEES (DI-GEST-FEES) was translated and validated by comparing ratings on other well-known assessment scales as reference measures. Analyses established that corre-lations were equal to or better for the Swedish version (Sw-DIGEST-FEES) com-pared to the reference measures used in the original development. Therefore, the Sw-DIGEST-FEES was deemed to be a psychometrically sound assessment tool. Study IV is based on an RCT evaluating the effect of preventive muscle-strengthening exercises on swallowing and mouth-opening function. Baseline results from FEES and mouth opening measurement were compared to measures made one-month after completion of radiotherapy for HNC. No statistically significant positive effect of the intervention protocol could be determined. Adherence to exercise protocol was 61%. Among participants in the intervention group who had completed ≥75% of exercises, there was a trend toward better outcomes. In conclusion, results from both RCTs are in line with previous research within the field-i.e., improving chronic swallowing difficulties is challenging, and preventive protocols for swallowing and mouth opening function is difficult to evaluate due to low adherence rates. The Sw-DIGEST-FEES can contribute to standardization of clinical and research results and offers psychometrically sound assessments.