The Influence of Physiotherapy and Climate on Functioning in Multiple Sclerosis. Aspects of physical performance, fatigue and health-related quality of life

Abstract

Multiple sclerosis (MS) is a chronic, immune-mediated disease affecting the central nervous system (CNS), caused by interplay between predisposing genes and environment. The disease may result in a wide spectre of functional problems, best treated by a multidisciplinary team of professionals. Physiotherapy has shown to improve physical functioning related to mobility and has been advocated as a major component in rehabilitation in MS. The CNS has the ability to change its function and structure depending on demands, and this neuroplasticity also occurs after damage. The Bobath concept is one of the most used treatment approaches in neurological physiotherapy and is based on knowledge of neuroplasticity, aiming to relearn appropriate movement strategies after damage. The thesis includes two intervention studies in MS. The first study is presented in Paper I. The second study (the climate study) is presented in Paper III. Data from the climate study are also used to investigate psychometric properties of a translated version of the self-reported health-related quality of life (HRQoL) questionnaire, the Multiple Sclerosis Impact Scale (MSIS-29) (Paper II), and to analyse associations between fatigue versus other variables (Paper IV). A single-subject experimental design was used in the first intervention study (Paper I), investigating the effect of three weeks of individualized daily outpatient physiotherapy based on the Bobath concept, for two patients being their own controls. Twelve repeated measures were performed over a time period of 17 weeks, using a wide spectre of measurement-tools. We concluded that balance and gait were improved after physiotherapy for the two patients, and that effect of treatment should be further evaluated in a larger study. In Paper II, the objective was to translate the MSIS-29 into Norwegian and to examine psychometric properties of the Norwegian version for use in the climate study. The questionnaire was answered by 64 patients prior to and at a screening session, and reanswered by 59 patients before and after four weeks of physiotherapy. Internal consistency (Cronbach’s ) was 0.92 for the physical- and 0.85 for the psychological subscale. Reliability by intraclass correlation coefficients were 0.86 for the physicaland 0.81 for the psychological subscale, smallest detectable change being 18.4 and 21.1, respectively. The physical- but not the psychological subscale demonstrated mostly satisfactory associations with other physical measures. Responsiveness by area under the receiver operating characteristics (ROC) curve was satisfactory, 0.83 and 0.76, respectively. As hypothesized, effect size was larger for the physical (1.01) than for the psychological (0.76) subscale after treatment. We concluded that MSIS-29, Norwegian Version demonstrated satisfactory psychometric properties. In the main intervention study (Paper III) the objective was to examine climate influence on the effect of physiotherapy in MS by comparing the effect of inpatient physiotherapy in a warm (Spain) versus a cold (Norway) climate in a short- and long term perspective. Sixty patients with gait problems and without heat intolerance were included in a randomized cross-over study of 4-week inpatient physiotherapy. Two groups of 30 patients were treated the first year in either Spain or Norway, and switching treatment centre the year after. The 6-minute walk test (6MWT) as the primary outcome measure, and other physical performance and self-reported measures, were used at screening, baseline, after treatment and at three- and six months followup. Treatment effects were analysed by mixed models. All assessment tools demonstrated improvement after treatment in both warm and cold climate, but to different degrees. After treatment, the mean walking-distance had increased by 70m in Spain and 49m in Norway (p=0.060), and improvement in favour of a warm climate was demonstrated at six months follow-up, 43m (Spain) compared to 20m (Norway) (p=0.048). The patients reported less exertion after walking (6MWT) in favour of treatment in Spain at all time points (p<0.05). No significant differences in change were detected for the other physical performance measures. Most self-reported measures showed more improvement after treatment in Spain, but these improvements were not sustained at follow-up. The results indicate that MS patients without heat intolerance have additional benefits from physiotherapy in a warm climate. In Paper IV, we also used data from the first part of the climate study. The aim was to investigate whether fatigue was associated with demographic-, clinical-, HRQoL- and physical performance variables, and whether change in fatigue after treatment was associated with changes in HRQoL and physical performance. Sixty patients were included for inpatient physiotherapy, and fifty-six completed the study. Fatigue (Fatigue Severity Scale; FSS), HRQoL (MSIS-29) and physical performance (walking ability and balance) were assessed at screening, baseline, after treatment and at followup after three and six months. We analysed possible associations between FSS and other variables at baseline by regression models, and between change in fatigue versus changes in HRQoL and physical performance variables after physiotherapy, by correlation analysis. We found that fatigue at baseline was associated with HRQoL (explained 21.9 % of variance), but not with physical performance tests. Change in fatigue was correlated with change in HRQoL, but not with changes in physical performance. All measures were improved after treatment (p 0.001). While improvements in fatigue and HRQoL were lost at follow-up, improvements in physical performance were sustained for at least six months (p 0.05). The findings suggest that fatigue in MS is not associated with physical performance as assessed in our study, but seemed to be associated with the patients’ experience of HRQoL. The results from both intervention studies indicate that physiotherapy based on the Bobath concept may cause improvement in physical performance in MS, in short- and long term perspectives. For patients without heat intolerance, there seems to be a favourable effect of treatment in a warm climate. The translated version of MSIS-29 demonstrated satisfactory measurement properties in line with the original English version and may therefore be recommended used as a measurement tool of HRQoL in patients with MS. If the aim of treatment is improvement of fatigue, a broader intervention, accounting for both physical and psychological aspects, seems necessary.