The indirect costs of multiple sclerosis: systematic review and meta-analysis

Abstract

The aim of this systematic review is to collect and summarize all current data on the indirect costs related to absenteeism and presenteeism associated with multiple sclerosis. Searches were conducted using Medline, Embase and Centre for Reviews and Dissemination databases. All collected costs were recalculated to average annual cost per patient, expressed in 2014 prices US$ using the consumer price index and purchasing power parity (scenario 1) and expressed as proportion of specific gross domestic product in current local currency unit to adjust for country’s development (scenario 2). Identified studies were then analyzed in order to assess their possible inclusion in the meta-analysis. The authors identified 63 records, of which 23 were eligible for meta-analysis. Overall indirect cost per patient calculated in scenario 1 was as high as US$20,167 with US$22,197 in Europe, US$17,382 in North America and US$153 in Asia. Overall indirect cost per patient calculated in scenario 2 was equal to US$16,939, with US$19,612 in Europe, US$11,592 in North America and US$899 in Asia. Overall indirect costs varied from US$3726 for patients with EDSS score less than 3 to US$19,264 for patients with Expanded Disability Status Scale score grater that 7. This review revealed the great economic burden of multiple sclerosis on society. The authors observed a great variety of the considered components of indirect costs and their definitions. Costs were higher for Europe than for other continents and were also higher for patients with a higher Expanded Disability Status Scale score.

Keywords:

• absenteeism
• cost of illness
• economic burden
• indirect cost
• multiple sclerosis
• systematic review

Financial & competing interests

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• Multiple sclerosis is a chronic inflammatory disease of the central nervous system causing neurodegeneration associated with axonal injury and demyelination.

• Multiple sclerosis has a great social and economic impact, because of the disease’s long duration, the higher prevalence and incidence among young adults, who are more prone to unemployment, which causes significant productivity losses.

• Considerable amount of identified studies and great variety of considered components on indirect costs, estimation approaches and methodologies reflect that this issue is quite well examined, but indirect costs data from different studies are difficult or just impossible to analyze.

• There is a great need of further studies focused on indirect costs of multiple sclerosis, especially the cost of presenteeism and premature death due to the illness, to facilitate the inclusion of societal perspective in the cost–effectiveness or cost-utility analyses.

• Overall indirect cost per patient calculated in scenario 1 was 20,167 US$, in scenario 2 it was 16,939 US$. In both scenarios, the highest costs were observed in Europe and the lowest in Asia. We observed that the higher the EDSS score the higher the indirect costs per patient.