The requirement for a disease-specific patient-reported outcome measure of dysphagia in oculopharyngeal muscular dystrophy

Introducing the Dysphagiameter: a novel patient-reported outcome measure for evaluating dysphagia in oculopharyngeal muscular dystrophy - from conceptual framework to initial development

Oculopharyngeal muscular dystrophy (OPMD) is a rare late-onset muscle disease associated with progressive dysphagia. As there was no patient-reported outcome measure specific for the assessment of dysphagia in OPMD, the Dysphagiameter was developed. The Food and Drug Administration guidance was followed. In Phase 1, a systematic literature review and an expert consultation were conducted to identify the concepts of interest. It was decided that the instrument should assess difficulty swallowing using pictures of foods of various textures (part A) and impact of dysphagia on activities and participation (part B), as defined by the International Classification of Functioning, Disability and Health. In Phase 2, focus groups (n = 3) and online surveys (n = 55) were conducted to generate the items. Then, the food items for part A were selected and grouped into 17 textures by a panel of registered dietitians. Cognitive interviews were conducted (n = 23) to refine the instrument and assess its clarity and comprehensiveness. The final draft included 82 food items assessing the capacity to swallow foods and drinks (part A) and 10 items assessing the impact of dysphagia on activities and participation (part B). Item reduction and assessment of psychometrics properties, using Rasch analysis, are ongoing as part of Phase 3.

Cross-cultural adaptation of the SWAL-QOL and the Sydney Swallow Questionnaire (SSQ) into French-Canadian and preliminary assessment for their use in an oculopharyngeal muscular dystrophy (OPMD) population

PURPOSE

Patient-reported outcomes (PRO) assessing dysphagia are an essential component of clinical trials to consider how patients feel and function in response to treatments. The selected PRO needs to be translated in several languages using a systematic process ensuring its validity and equivalence for use in multicenter clinical trials. The main objectives were to translate the SWAL-QOL and the Sydney Swallow Questionnaire (SSQ) into French Canadian (SWAL-QOL-FC and SSQ-FC) and to assess their appropriateness for patients with oculopharyngeal muscular dystrophy (OPMD).

METHODS

A forward- and back-translation process was followed including independent mother-tongue translators followed by committee review. Known-groups validity was assessed by comparing scores of OPMD French-Canadian participants (n = 21) known to differ in dysphagia severity according to the 80-ml drinking test score. A Mann-Whitney test was used to compare the mean scores. Cognitive interviews were conducted later on to ensure a posteriori cultural equivalence among French-Canadian participants (n = 28).

RESULTS

Evidences of adequate known-groups validity was shown for the SSQ-FC. Only two domains out of 10 of the SWAL-QOL-FC (burden and eating duration) showed adequate known-groups validity. In addition, the difference in the mean composite score was not significant. Several conceptual equivalence issues were found in both questionnaires as a result of the cognitive interviews.

CONCLUSION

This study provided evidence that the SSQ-FC presents better validity than the SWAL-QOL-FC in a small sample size of OPMD participants. The findings of the cognitive interviews suggest the need to develop an OPMD-specific questionnaire to capture better the whole spectrum of disease severity.

Nutritional Risk in Oculopharyngeal Muscular Dystrophy: Beyond Dysphagia

Purpose: To document the nutritional risk in adults with oculopharyngeal muscular dystrophy (OPMD) and its association with oropharyngeal dysphagia.Methods: In this cross-sectional study, 33 adults with molecular confirmation of OPMD between 50 and 75 years old were recruited from the registry of a university-affiliated neuromuscular clinic. Nutritional risk was assessed with the French version of Seniors in the Community: Risk Evaluation for Eating and Nutrition II (SCREEN II), whereas the severity of dysphagia was assessed using the French-Canadian version of the Sydney Swallow Questionnaire. Anthropometric measurements were performed with standardized procedures.Results: SCREEN II scores showed high nutritional risk for 81.8% of OPMD participants with 6 factors contributing to nutritional risk in at least 50% of the sample. Pearson's correlational analysis showed a significant moderate relationship between dysphagia and nutritional risk (r = -0.470; P = 0.006).Conclusion: To our knowledge, this study is the first to investigate the nutritional risk of adults with OPMD. Our results indicate that individuals with OPMD may be at high nutritional risk mostly associated with swallowing difficulty, in the absence of a low body mass index. The present study highlights the need for dietary counseling in OPMD.

Dysphagia in adult myopathies

Dysphagia (impaired swallowing) is not a rare problem in various neuromuscular disorders, both in the pediatric and the adult patient population. On many occasions such patients are first presented to other medical specialists or health professionals. Disorders of deglutition are probably underrecognized in patients with a neuromuscular disease as a result of patient's and doctor's delay. This review will focus on dysphagia in adults suffering from a myopathy. Dysphagia in myopathies usually affects the oropharyngeal phases which rely mostly on voluntary muscle activity of the mouth, pharynx and upper esophageal sphincter. Dysphagia is known to contribute to a reduction of quality of life and may also lead to increased morbidity and mortality. The review includes an overview on symptomatology and tools of assessments, and elaborates on dysphagia in specific hereditary and acquired myopathies.