Pain due to multiple sclerosis: Analysis of the prevalence and economic burden in Canada

BACKGROUND: Multiple sclerosis (MS) is a neurological disease affecting approximately 50,000 Canadians. Although studies have described overall MS costs, none have focused specifically on MS-related pain. OBJECTIVES: To estimate the prevalence of MS-related pain in Canada, the proportion of patients treated and responding to treatment for MS-related pain, and the associated economic burden. METHODS: Results were captured through physician and patient surveys. Patients were recruited through MS clinics and the MS Society. Patient-reported outcomes and resource utilization over the previous six months were collected by telephone interview. Costs were measured in 2004 Canadian dollars. The economic burden was extrapolated to the population using national demographics and prevalence. Spearman's. assessed the relationship between cost and pain severity. RESULTS: Physicians estimated that 46% of their MS patients experienced MS-related pain, and that 35% received treatment for pain. Pain was reported to be relieved somewhat in 29%+/- 10% of their patients, adequately in 26%+/- 19% and poorly in 27%+/- 13%, while 17%+/- 9% received no relief. Two hundred ninety-seven participants completed the patient survey. Seventy-one per cent (211 of 297 patients) experienced MS-related pain. Eighty per cent of patients reported taking some type of medication to manage their pain, and of these, 82% reported some reduction in pain. The mean +/- SD direct cost per patient of MS-related pain was $2,528 +/- 5,695. The mean +/- SD indirect cost per patient was $669 +/- 875. Total costs were positively correlated with levels of self-reported pain (rho=0.291, P<0.0001). The estimated six-month burden of pain of MS patients in Canada was $79,444,888. CONCLUSIONS: The prevalence of pain is high in MS patients. This condition may be underdiagnosed and undertreated, and results in a significant economic burden on society.