Direct and indirect cost burden associated with multiple sclerosis relapses: excess costs of persons with MS and their spouse caregivers

Abstract

Background: MS relapses are unpredictable and can be concerning to patients and their caregivers.

Objective: To assess the direct and indirect cost burden associated with relapses of different severities in MS patients and with MS relapse frequency on spouse caregivers.

Methods: Using a U.S. insurance claims and employee disability database (1999-2011), we studied adult MS patients (ICD-9-CM: 340.x) and their spouse caregivers. A previously published algorithm to identify relapses was used to stratify: (1) MS patients into cohorts of no, low/moderate, and high severity relapse based on the most severe relapse within one year of follow-up (if any); (2) caregivers into cohorts of no, less, and more frequent relapses based on the overall frequency of relapses of their spouse. Adjusted cost differences and 95% confidence intervals evaluating the yearly incremental costs at 12 months of follow-up (MS patients) and overall (caregivers) associated with relapses are reported.

Results: Among the 9421 MS patients (N: no relapse=7686; low/moderate severity relapse=1220; high severity relapse=515) identified, both relapse cohorts incurred significantly higher annual incremental direct costs than the no relapse cohort (low/moderate severity=$8269 [6565-10,115]; high severity=$24,180 [20,263-28,482]) and indirect costs (low/moderate severity=$1429 [759-2147]; high severity=$2714 [1468-4035]). More frequent relapses versus no relapse also translated into a significantly greater cost burden for caregivers (direct+indirect=$1725 [376-2885]) but less frequent relapses did not.

Conclusions: Relapse severity was significantly and increasingly associated with greater direct and indirect costs in MS patients. More frequent relapses also translated into a significant cost burden in spouse caregivers.