Comorbidity and Health-Related Quality of Life in People with Multiple Sclerosis

Abstract

This study examined associations between comorbidity and health-related quality of life (HRQL) in people with multiple sclerosis (MS). Data were derived from the Canadian Community Health Survey (CCHS) Cycle 1.1, a cross-sectional survey conducted by Statistics Canada. A nationally representative sample of community-dwelling Canadians was interviewed to determine whether they had been diagnosed with various chronic conditions. Participants were also administered the Health Utilities Index Mark 3 (HUI3) questionnaire to evaluate HRQL. Of the 131,535 participants, 335 reported having MS. Comorbidities listed by at least 10% of respondents with MS were assessed for their relation to HRQL, with age, sex, education, marital status, income, and number of comorbidities included as covariates. Respondents averaged 1.6 comorbidities. Eight comorbidities were experienced by at least 10% of respondents: back problems (35%), nonfood allergies (29%), urinary incontinence (28%), arthritis (26%), hypertension (17%), chronic fatigue syndrome (16%), depression (16%), and migraine (14%). Differences in HRQL between people with and without urinary incontinence, arthritis, hypertension, chronic fatigue syndrome, and depression were either clinically important or statistically significant at the .05 level in bivariate analyses. Only urinary incontinence and depression, however, were negatively associated with HRQL in a multivariate analysis, which explained 26% of the variance. Lower levels of education and receiving social assistance were also negatively associated with HRQL, with social assistance contributing more to the variance in HRQL than either comorbidity.