Economic burden of multiple sclerosis in a population with low physical disability

Multiple sclerosis (MS) is a chronic autoimmune neurological disease with a high impact on the health-related quality of life of individuals, their families and society [1‐5]. MS is typically diagnosed in young, active people between 20 and 40 years of age [6]. Therefore, the disease may hinder ability to maintain studies and work [1‐4]. According to the Global MS Employment Report 2016, 43% of unemployed people with MS quit their employment in the first 3 years after diagnosis and 62% stated that fatigue was the main reason [7]. In addition, pwMS will require caregiving due to disability progression, mostly provided by informal caregivers, such as partners or other relatives [5].

Total average annual costs were €41,212 ± €18,761 in an observational study of 1152 pwMS and 265 caregivers conducted in 19 countries [3]. Over half of total costs were associated with direct medical costs, followed by indirect costs (€17,492) and direct non-medical costs (€2157). In some European countries, MS caregivers provide 150 h a month of care to pwMS, the equivalent of full-time employment [1]. The mean annual cost per patient in Spain was €30,050 [8]. Sicras et al. found that only 30% of MS people were employed or self-employed [9]. More than 30% of pwMS had an early retirement, in most cases due to disability. Indirect costs in Spain accounted for between 24 and 35% of disease costs, increasing as disability advanced, and reaching over €15,779 in subjects essentially restricted to a wheelchair [8]. However, available data related to the economic burden of MS, especially limitations in work activities and job performance remains limited. The objective of this study was to assess the indirect costs and informal care costs of MS in a sample of pwMS in Spain.

A total of 199 pwMS were included in the study. Subjects were predominantly female (60.2%), with a diagnosis of RRMS (86.1%) and a mean age of 43.9 ± 10.5 years. The median EDSS score was 2.0 (interquartile range 1.0, 3.5). Table 1 shows the main demographic and clinical characteristics of the sample.

Most subjects (70.4%) were employed at MS diagnosis, but only 47.2% were employed at the time of the study visit (Fig. 1). Mean time between MS diagnosis and the study visit was 9.6 years (SD 7.2). The mean age for retirement was 43.6 ± 10.5 years, with disease progression as the main reason (95.7%). According to the results collected from the MSWDQ-23 and MSIS-29 questionnaires, the main impact of MS on subjects’ activities was due to external and physical barriers, especially in those patients with PPMS (Fig. 2).

During the last year prior to the study visit, the mean free time that subjects had was 45.7 ± 35.8 h/week. PwMS dedicated 35.5 ± 17.9 h/week to their studies and 36.2 ± 10.8 h/week to their work activity. Sick leaves were reported in 10.1% of the total MS population and absenteeism was seen in 90.9% of the student population and 30.9% of the employed population (Table 2).

About a third (36.2%) of pwMS went to the study visit accompanied by a formal caregiver and almost half (44.7%) by an informal one (Table 3). The most frequent informal caregiving was provided by a direct relative (55.82%) (Table 3). The mean time spent on caregiving activities for these informal caregivers was: husband/wife (212.14 ± 516.86 h/year); other relative (154.19 ± 503.18 h/year), and neighbor (3.02 ± 21.97 h/year). A total of 72 caregivers completed the CSI (mean total score was 3.9 ± 3.4). The prevalence of a high level of strain was 23.6% (n = 17).

Over a quarter (28.1%) of pwMS needed paid professional support to maintain their daily life activities, mainly a person to do housework (0.5 ± 2.3 h/week and 4.4 ± 14.5 weeks/year) and a physiotherapist (0.4 ± 1.0 h/week and 5.3 ± 14.8 weeks/year) (Table 4).

The mean (SD) annual cost associated with sick leaves due to MS was €416.6 ± 2030.2, with work absenteeism due to MS accounting for €763.4 ± 3161.8, premature retirement due to MS for €5810.1 ± 13,159, and premature work disability/ pensioner for €1816.8 ± 9630.7 per patient (Table 5). The sum of all these indirect costs resulted in an average cost per patient per year of €8806.9. Considering caregiving activities, professional staff cost was €1026.9 ± 4622.0 and informal caregiving activities had a cost of €301.7 ± 1160.0, resulting in a total average cost for caregiving activities of €1328.7. Finally, the mean cost of MS devices needed by pwMS was €736.6 ± 2756.4. All these costs were considered to be average for MS subjects.

The economic cost of MS is largely driven by indirect costs that are linked to early and very high unemployment rates [1‐4, 17, 18]. As stated earlier, this study provides a better understanding of the impact of MS on Spanish patients’ working activity, allowing for an updated estimation of the indirect costs of MS. Our study shows an employment rate of 47.2% and a mean age of retirement of 43.6 years in a clinically stable sample of 199 pwMS mostly with a low level of physical disability (median EDSS score of 2.0). Almost a quarter (22.4%) of pwMS retired early because of the condition and 7% received an incapacity benefit or pension due to MS. Ten percent of the population had sick leaves (absenteeism was seen in 90.9% of the student population and 30.9% of the employed population). Costs associated with work limitations to employed subjects were almost seven times greater than costs from professional support and 30 times greater than costs from informal caregiving. Among all costs, those with the higher value are the costs associated with premature retirement according to our sample population (women fully incorporated into working life). These results are consistent with several prior studies. Kobelt et al. found that productivity losses and informal care dramatically increased from €593 at early-stage disease to nearly €34,228 at EDSS scores > 7 [19]. Subsequently, the TRIBUNE study also showed the correlation between disability and economic impact [20]. The overall annual indirect costs associated with MS were estimated at between €207 and €440 million due to productivity losses caused by lost work hours and early retirement (27 and 33% of the total cost, respectively) [21, 22].

A high rate of unemployment also occurs at a level of disability which is typically not associated with overt physical disability [1, 17]. Less visible symptoms and difficulties including cognitive impairment, fatigue, anxiety and depression are reasons for low productivity and unemployment at low EDSS scores. Kobelt et al. also found an employment rate of 45% in a sample of 462 pwMS in Spain with an EDSS score between 0 and 3 [23]. Fatigue and cognitive complaints were found in 92 and 64% of participants, respectively. Fatigue and cognitive disturbances are much more common than mobility problems in people who are working [8, 19]. MS-related productivity loss due to presenteeism was three times that of absenteeism in a study with 740 MS employees conducted in Australia [4]. The mean total work productivity loss was 2.5 days (14.2% loss in productive time), based on an absenteeism of 0.6 days (3.4%) and a presenteeism of 1.9 days (10.8%), leading to a €4578 loss per person annually. Work productivity was determined mostly by fatigue, cognitive impairment, pain and sensory symptoms [4].

There is increasing evidence to advocate the use of more effective therapies at earlier stages of the disease [24‐27]. The IMPrESS study showed that pwMS treated earlier in the course of the disease showed a trend towards lower total (€39,037 vs €42,996), indirect (€15,733 vs €18,934) and disease-modifying therapy (€19,364 vs €20,491) costs and a better health-related quality of life status (0.62 vs 0.56; p < 0.01) compared to those receiving late treatment [3]. Chen et al. found that pwMS receiving high-efficacy disease-modifying therapy reported significant increases in amount of work, work attendance and work productivity compared with those using first-generation injectable treatments [27].

Our study has several limitations. Recall bias is a common concern of studies using self-reported data. The relatively small sample size and the cross-sectional design could be additional limiting factors of this study. A salary was set based on the range indicated by the participant (mid-point). For cases where only the salary at the time of diagnosis was available, the point of the range was adjusted using the CPI for the respective year. Another limitation is not having considered the time lost due to disease for pwMS without paid work, since it was unknown during the study.

MS has classically been reported as being responsible for high indirect costs and other substantial economic burden in Spain. Symptom severity has strong impact on both work productivity and workforce participation. This study shows that indirect and caregiving costs are incurred even at low levels of physical disability. Effective therapeutic interventions to improve the management of early symptoms as well as implementing workplace strategies focused on job retention may be essential to decrease the high economic burden of MS.