Validation of the Persian version of the dysphagia in multiple sclerosis questionnaire for the assessment of dysphagia in multiple sclerosis

Dysphagia in neuromyelitis optica spectrum disorder and multiple sclerosis: A comparison of frequency, severity, and effects on quality of life

OVERVIEW

Dysphagia has been previously discussed as a potential life-threatening condition secondary to chronic neurological diseases such as multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD). However, its impact on the quality of life (QoL) of patients with NMOSD has never been studied before. This study aims to determine the frequency of dysphagia and its impact on QoL in NMOSD patients in comparison with MS people and healthy individuals.

METHODS

Seventy-five MS and sixty-five NMOSD patients with an expanded disability status scale (EDSS) score ≥ 3.5 in addition to 106 healthy controls were enrolled in this cross-sectional study. All the participants completed the self-report dysphagia in MS (DYMUS) and 36-item short-form health survey (SF-36) questionnaires. In case of positive answers to at least one of the questions in DYMUS, they were asked to fill out the dysphagia handicap index (DHI) questionnaire.

RESULTS

The frequency of dysphagia in NMOSD, MS, and control groups was 61.54 %, 72.97 %, and 27 %, respectively. Patients with swallowing problems had reduced scores across different swallowing-related QoL domains compared to non-dysphagic patients (p < 0.05). NMOSD (1, IQR [0-3.5]) and MS patients (2, IQR [0-4]) had a significantly higher median total DYMUS score than control (0, IQR [0-1]) (p < 0.01). However, there was no discernible difference between the two patient groups. NMOSD had the highest mean total DHI score (21.22 ± 21), followed by MS (15.25 ± 18.94) and control (7.08 ± 5.12). A significant correlation was seen in the NMOSD group between the DHI total score and the SF-36 total score (r = 0.62, p < 0.05). The DHI and SF-36 subscales showed a strong association as well. The overall SF-36 scores in both the control and MS groups was not significantly correlated with DHI. The generalized linear model analysis showed that the NMOSD group's age (p-value = 0.005), EDSS (p-value < 0.001), and total DYMUS score (p-value = 0.018) significantly affected overall health status.

CONCLUSION

The presence of dysphagia significantly impacts the QoL in NMOSD patients, particularly in aspects related to swallowing. These findings underscore the critical need for diligent dysphagia screening and emphasize the importance of educating both caregivers and NMOSD patients about managing this challenging symptom.

Validation of the Spanish version of DYsphagia in MUltiple Sclerosis questionnaire (DYMUS)

BACKGROUND

Dysphagia is a common symptom in multiple sclerosis that can occur even early in the disease course and can lead to serious complications. Early recognition and treatment can promote comfort, safety and optimal nutritional status. Few dysphagia rating scales are available in Spanish. The aim of this study was to translate the Dysphagia in Multiple Sclerosis Questionnaire (DYMUS) into Spanish and to validate it.

METHODS

Forward and backward translation method was used to translate the original English version of DYMUS into Spanish. A pilot-study with 10 PwMS was carried on in order to improve the intelligibility of the instrument, comprehensibility and content validity of the questionnaire. The questionnaire was filled out by 100 PwMS who were asked a dichotomous question on their swallowing ("Do you have swallowing troubles?"). Descriptive data are presented as median and quartiles for continuous variables and frequency and percentage for categorical ones. Internal consistency reliability was estimated by Cronbach's alfa. Test-retest reliability was estimated by intraclass correlation coefficient. Concurrent validity with a speech and language therapy assessment (SLT-A) was measured with the weighted kappa statistic for the concordance for both dysphagia type and degree categories. Confirmatory factor analysis by means of structural equation models was used to verify the two-factor (solids and liquids) structure of the DYMUS questionnaire. As the goodness of fit evaluation was poor, an additional exploratory factor analysis was carried out.

RESULTS

Internal consistency was high. The globus sensation question and the weight loss questions (item 3 and 10) are the least specific with dysphagia symptomatology so they are worst correlated with the sum of the others (item-rest correlation, 0.243 and 0.248, respectively). The test-retest reliability of the DYMUS among 40 patients using ICC was 0.75 (95% CI 0.57 - 0.86). Concurrent validity with SLT-A was poor (weighted kappa 0.37 for dysphagia type and 0.38 for dysphagia degree). The DYMUS questionnaire detected three times more dysphagia (53% versus 17%) than the dichotomous question. Confirmatory factors analysis failed to confirm the bidimensional structure (solid and liquid items) often reported in other validation studies. The subsequent exploratory factor analysis also identified two factors, but with poor interpretability.

CONCLUSION

DYMUS-SP scale is not a sufficiently useful scale to detect dysphagia in PwMS due to the poor concurrent validity and the probable overdiagnosis of the condition; however, it can be helpful as a screening tool when combined with other measures.

Validation of the Czech Version of the Dysphagia in Multiple Sclerosis Questionnaire (DYMUS)

Dysphagia is a common symptom of neurological disease, including multiple sclerosis (MS). The DYsphagia in MUltiple Sclerosis (DYMUS) questionnaire was developed as a screening tool for swallowing problems. The purpose of the present study was to validate the Czech version of the DYMUS questionnaire. We validated the questionnaire on a sample of 435 patients with MS and 135 healthy controls (HC) chosen by accidental sampling from larger, long-term studies conducted by the Prague MS Center. For the purposes of this study, we used both electronic (primary method of distribution) and paper-based (backup) versions of the questionnaire. The internal consistency of the whole scale was satisfactory (Cronbach’s α =0.833). The DYMUS mean score in HC was 0.215 (standard deviation [SD] = 0.776). Normative data suggested a cut-off value for dysphagia between 1 and 2 points. Principal component analysis (PCA) showed a two-factor structure of the adapted scale. However, the structure did not completely correspond to the originally proposed dimensions of dysphagia for solids and liquids; our data supported dropout of item Q10. Criterion validity was proved by the difference in dysphagia between HC and patients MS (U = 25,546, p < 0.001) and by a positive correlation with the EDSS (Kendall’s tau-b = 0.169, p < 0.001) and other patient-reported outcomes. The Czech version of the DYMUS questionnaire is a valid and reliable tool for evaluating swallowing impairment in Czech-speaking patients with MS. Moreover, the questionnaire can be administered electronically, with a paper-based backup.