Validation of the Brazilian version of the patient-determined disease steps scale in persons with multiple sclerosis.

OBJECTIVE: The present study translated and adapted the Brazilian version of the Patient-Determined Disease Steps (PDDS) scale and tested its validity and reproducibility in Brazilian persons with multiple sclerosis (MS). METHODS: The PDDS underwent translation and back-translation procedures for producing a Brazilian Portuguese version of the PDDS (PDDS/BR). Sixty-three patients with MS (48 females) completed the PDDS/BR and underwent a neurological examination for generation of Expanded Disability Status Scale (EDSS) scores. Participants further performed the following tests: Timed 25-Foot Walk (T25FW), Timed Up and Go (TUG), six-minute walk test (6MWT), Nine Hole Peg (9HPT), and Symbol Digit Modalities Test (SDMT). Construct validity of PDDS/BR scores was determined by Spearman correlation with EDSS, and comparison of correlations between PDDS/BR and EDSS with the functional tests. We examined overall correct classification of disability categories (i.e., mild, moderate, or severe disability) by the PDDS/BR in relation to the EDSS. Test-retest reproducibility of PDDS/BR scores was examined in a subsample of 31 participants after 15 days. RESULTS: There was a strong relationship between the PDDS/BR and EDSS scores (ρ = 0.723, p < 0.05). The correlations with TUG, T25FW, 6MWT, and 9HPT were comparable for the PDDS/BR and EDSS scores. Overall correct classification of disability categories by the PDDS/BR was 79.3%. Results indicated excellent test-retest reproducibility for the PDDS/BR (Intraclass Correlation Coefficient= 0.911, 95% CI: 0.685-0.918). CONCLUSION: The PDDS/BR scores provide a valid and reliable assessment of mobility disability and may be used by researchers and neurologists to assess disability status in Brazilians with MS.

Knee flexor strength and balance control impairment may explain declines during prolonged walking in women with mild multiple sclerosis.

BACKGROUND: Physiological factors such as muscle weakness and balance could explain declines in walking distance by multiple sclerosis (MS) patients. The purpose of this study was to characterize levels and examine associations among decline in walking distance, balance and muscular strength in women with mild MS. METHODS: Participants included 28 women with mild relapsing-remitting MS and 21 women without MS. We executed the 6-min walk test (6MWT) to verify declines in walking distance. Isokinetic knee flexion (KF) and extension (KE) muscle strength was measured using a dynamometer. Balance was quantified using a force platform, with eyes open and closed, on a rigid and foam surface. RESULTS: The MS patients presented declines in walking, lower KF muscle strength, and worse balance than controls. KF strength and balance correlated with walking in the MS group. The KF strength explained differences between groups in walking. The KF strength and balance presented as predictors of walking slowing down in the 6MWT, in mild MS. CONCLUSION: Women with mild MS have strength impairment of knee flexor muscles and balance control impairment that may explain walking related motor fatigability during prolonged walking.