Societal Costs of Primary Progressive Multiple Sclerosis (PPMS)

Executive Summary
Introduction
Multiple sclerosis (MS) is one of the most common chronic debilitating neurological (central nervous system) diseases. Primary progressive multiple sclerosis (PPMS) is one of the clinical subtypes of MS. Very few studies both overseas and in Australia have examined the costs specifically associated with PPMS and the economic burden placed on individuals, families, health services, Government and society at large.
This study addresses two key questions:
1.What are the broader societal costs of PPMS in Australia? and
2.What is the economic impact of increasing the level of independence of people with PPMS through delaying disease progression?
Methods
The study adopts a cost of illness (COI) approach taking a bottom-up prevalence-based retrospective perspective. It draws on existing publicly available secondary data and findings in the literature. Both direct and indirect costs are estimated with cost items including: hospitalisation; medical and health professional services; medical tests; PBS medicines and other medications; residential care; home care and support programmes; NDIS packages; the disability support pension; lost productivity of people with PPMS including absenteeism and presenteeism; cost of informal care; and carers payments and benefits. Data was accessed from a wide range of data sources to estimate costs. This included survey and administrative datasets as well as using information provided in the Australian and international literature on MS and PPMS in particular. All costs were uprated to 2018 dollars using appropriate inflators.
Overview of PPMS
PPMS occurs in 10-15% of people. The average age of onset of PPMS is around 40 years of age, with PPMS being very rare in children and teenagers. Unlike other types of MS, there are typically similar numbers of males affected by PPMS as females. The natural history of PPMS indicates that disease progression is relatively rapid. The median time to progress from disease onset to moderate disability is around 3 years and 4 years from moderate to severe disability. People with PPMS are typically older and have greater disease severity than those with other types of MS.
As MS impacts people of working age, many individuals experience presenteeism, absenteeism or are forced to reduce their working hours, change their jobs or leave the workforce prematurely. Disease severity and type of MS strongly influence the proportion of participants below retirement age who are in employment. Employment rates of people with PPMS are especially low, and absenteeism and presenteeism are experienced by a large proportion of the population.
People with PPMS receive care and support through formal community and home care and support services, residential (aged care) care and from informal carers who usually are family members, friends or neighbours. Increasing numbers of persons under 65 years of age are now receiving support packages through the NDIS, and older persons in the community are accessing the Government Home Care Packages Programme or services provided through the Commonwealth Home Support Programme. Because of their severe disability, increased numbers of persons with PPMS are residents of residential care and supported accommodation services. Nevertheless, support from informal caregivers remains the dominant form of care used by persons with PPMS. Studies show that MS has an impact not only on the quality of life of MS patients but also their caregivers. A key aspect of the caregiver burden is the impact on carers’ employment and loss of income.
Using data from the 2015 ABS Survey of Disability, Ageing and Carers, it was estimated that around 31,650 Australians would have MS, 14% of whom would have PPMS (4,430). PPMS is most prevalent in persons with MS aged 65 years and over, and over half (56%) of those with PPMS are thought to have severe disability.
Costs of PPMS in Australia
The findings of this COI study show that the economic burden of PPMS is high at an estimated $418.056 million in 2018. The results are consistent with findings from the international literature and other economic impact studies in Australia.
Costs increased significantly with disease severity from $23.178 million for individuals with mild PPMS to $311.149 million for those with severe disability, a 13-fold increase in total annual costs. Indirect costs were found to contribute to 67% of the total cost of PPMS, reflecting both the age of patients and the level of disease severity. This was similar to the breakdown of costs reported for people with PPMS in the 2016 Australian Economic Impact Survey (EIS). Informal care costs were the largest component of total costs at 27.1% followed by lost productivity (21.4%) from PwPPMS retiring from the workforce, reducing their hours of work or changing jobs. In the 2016 EIS the respective percentages were 21.6% and 24.2%. Absenteeism and presenteeism contributed to a further $6.311 million.
Support provided by Government is significant with the NDIS estimated to be contributing now to nearly 10% of annual costs of PPMS, the DSP to over 9% and carer payments a further 8%. Given the level of disability of people with PPMS, the need for residential care and formal home care and support is considerably higher than that expected from rates within the general population, with PPMS contributing to an expected additional $57.561 million in expenditure in 2018.
The introduction of an effective disease modifying therapy that could delay disease progression by an additional year from mild to moderate disability and a further year from moderate to severe PPMS was modelled. While major savings are made for people with moderate and severe disability, these are partly offset by increased costs with increasing numbers having mild PPMS. Nonetheless, this modelling indicated that the societal cost of PPMS in Australia could be reduced by nearly $15 million per year, an overall savings of 3.6% if such an intervention could be introduced.
Conclusions
There are very few studies that have focussed on the societal costs of PPMS both internationally and in Australia. The findings presented in this Report add to the evidence base that shows the economic burden of PPMS is high. People with PPMS are on average older and have greater disease severity than individuals with either RRMS or SPMS. This reflects in higher care needs and support, and lower rates of workforce participation and productivity. However, the modelling shows that the introduction of an effective disease modifying therapy that delays disease progression would not only improve patients’ subjective well-being and quality of life but also lead to major cost-savings.