Updated cost-of-care estimates for commercially insured patients with multiple sclerosis: retrospective observational analysis of medical and pharmacy claims data

Abstract

Abstract Background For patients with multiple sclerosis (MS), previous research identified key disease sequelae as important cost drivers and suggested that among users of disease-modifying drugs (DMDs) in 2004, DMDs represented 73% of the total cost of care. More recent studies were limited to incident disease/treatment and/or excluded DMDs from cost estimates. To support contemporary pharmacoeconomic analyses, the present study was conducted to provide updated information about MS-related costs and cost drivers including DMDs. Methods For each of 2 years, 2006 and 2011, commercially insured, continuously eligible patients with ≥ 1 medical claim diagnosis of MS were sampled. MS-related charges were based on medical claims with MS diagnosis plus medical/pharmacy claims for DMDs. 2006 charges were adjusted to 2011 $ using the medical care component of the consumer price index (CPI). Subgroups of patients using DMDs (interferon [IFN] beta-1a intramuscular or subcutaneous, IFN beta-1b, glatiramer, natalizumab) in 2011 were identified. By-group differences were tested with bivariate statistics. Results Mean (standard deviation [SD]) age of 15,902 sample patients in 2011 was 47.6 (11.8) years, 76% female. Mean [SD] MS charges ($26,520 [$38,478] overall) were significantly (P < 0.001) higher for patients with common disease sequelae: malaise/fatigue (n = 2,235; $39,948 [$48,435]), paresthesia (n = 1,566; $33,648 [$45,273]), depression (n = 1,255; $42,831 [$51,693]), and abnormality of gait (n = 1,196; $48,361 [$55,472]). From 2006 to 2011, CPI-adjusted MS charges increased by 60%. Among patients treated with a single DMD in 2011, inpatient care was 6% of charges (range = 4%-8%; P = 0.155); outpatient care was 19% (range = 14%-20% except for natalizumab [29%]; P < 0.001); and DMDs were 75% (range = 67%-81%; P < 0.001). Conclusions Common MS sequelae remain important cost drivers. Although MS treatment costs are increasing, the proportion of MS charges due to DMDs in 2011 is similar to that reported in 2004.