OBJECTIVES: The Sclerosis Impact study (2017) has previously found that multiple sclerosis (MS) has a major impact on societal costs in Denmark. The aim of the present study is to estimate the indirect costs of MS incurred by informal caregivers (ICs).

METHODS: All MS patients and their ICs were ascertained, together with data on healthcare resource utilization, nursing care consumption and productivity loss during 2014, using the national health registers. The 14,786 individuals presenting with MS in year 2014 were matched with control population by age and gender. Indirect costs were compared between the ICs of MS patients and those of controls, with stratification of the MS patients according to MS duration: 0-9; 10-19; 20-29; +30 years from MS debut to year 2014.

RESULTS: There were 15,412 ICs (39% female) of MS patients and 96,818 ICs (41% female) of controls. The healthcare costs among ICs of MS patients with 20-29 years MS duration were 18,679 DKK per person-year and with 30+ years of MS were 24,194 DKK, being 5,225 DKK and 10,739 DKK higher compared to controls. The male and female ICs of MS patients with +30 disease duration had on average 9,837 DKK and 366 DKK nursing care costs respectively, being 5,155 DKK and 61 DKK higher compared to family members of controls. The MS-attributable productivity loss among male ICs was 6,604 DKK in +30 cohort, while total costs were 25,717 DKK. The total and MS-attributable costs per IC’s person-year, stratified by disease duration were: 35,074 DKK and -2,950 DKK within 0-9 years; 37,565 DKK and -823 DKK within 10-19 years; 45,131 DKK and 5,984 DKK within 20-29 years; 58,833 DKK and 21,004 DKK within +30 years.

CONCLUSIONS: Total MS-attributable costs among ICs increase with disease duration, primarily driven by healthcare costs and productivity losses and particularly seen in males.