Physical activity and quality of life in multiple sclerosis: intermediary roles of disability, fatigue, mood, pain, self-efficacy and social support

Abstract

Physical activity has been associated with a small improvement in quality of life (QOL) among those with multiple sclerosis (MS). This relationship may be indirect and operate through factors such as disability, fatigue, mood, pain, self-efficacy and social support. The present study examined variables that might account for the relationship between physical activity and QOL in a sample (N = 292) of individuals with a definite diagnosis of MS. The participants wore an accelerometer for 7 days and then completed self-report measures of physical activity, QOL, disability, fatigue, mood, pain, self-efficacy and social support. The data were analysed using covariance modelling in Mplus 3.0. The model provided an excellent fit for the data (chi(2) = 51.33, df = 18, p < 0.001, standardised root mean squared residual = 0.03, comparative fit index = 0.98). Those who were more physically active reported lower levels of disability (gamma = -0.50), depression (gamma = -0.31), fatigue (gamma = -0.46) and pain (gamma = -0.19) and higher levels of social support (gamma = 0.20), self-efficacy for managing MS (gamma = 0.41), and self-efficacy for regular physical activity (gamma = 0.49). In turn, those who reported lower levels of depression (beta = -0.37), anxiety (beta = -0.15), fatigue (beta = -0.16) and pain (beta = -0.08) and higher levels of social support (beta = 0.26) and self-efficacy for controlling MS (beta = 0.17) reported higher levels of QOL. The observed pattern of relationships supports the possibility that physical activity is indirectly associated with improved QOL in individuals with MS via depression, fatigue, pain, social support and self-efficacy for managing MS.

Figures

Figure 1

Model that was tested for understanding the association between physical activity and quality of life in a sample of 292 individuals with multiple sclerosis. Note: The factor loadings and path coefficient are standardised estimates and statistically significant. GLTEQ, Godin Leisure-Time Exercise Questionnaire; Accel, accelerometer counts; LMSQOL, Leeds Multiple Sclerosis Quality of Life Scale; SLWS, Satisfaction With Life Scale.

Figure 2

Model that was tested for understanding the associations among physical activity, disability, fatigue, mood, pain, self-efficacy, social support, and quality of life in a sample of 292 individuals with multiple sclerosis. Note: All coefficients are standardised estimates. Solid lines represent statistically significant paths, and dashed lines represent non-significant paths. GLTEQ, Godin Leisure-Time Exercise Questionnaire; Accel, accelerometer counts; Disability, Patient Determined Disease Steps Scale; Anxiety, Anxiety subscale of Hospital Anxiety and Depression Scale; Depression, Depression subscale of Hospital Anxiety and Depression Scale; Fatigue, Fatigue Severity Scale; Pain, Short-form of McGill Pain Questionnaire; Social Support, Social Provisions Scale; Self-efficacy for MS, Multiple Sclerosis Self-Efficacy Scale; Exercise Self-efficacy, Exercise Self-Efficacy Scale; LMSQOL, Leeds Multiple Sclerosis Quality of Life Scale; SLWS, Satisfaction With Life Scale.