Figures and tables in The Development of a Microsimulation Model (MitoMOD) to Estimate the Economic Impact of Mitochondrial Disease in Adults

Abstract

Mitochondrial diseases (MITO) are serious and debilitating conditions, often multisystemic and requiring life-long monitoring and treatment of symptoms to reduce the risk of a life-threatening episode or acute illness. The disease is caused by mutations either in the mitochondrial DNA (mtDNA) or nuclear DNA (nDNA), resulting in impaired production of cellular energy from the affected mitochondrial organelles. MITO closely resembles other conditions due to its wide clinical presentation and genetic heterogeneity. While mitochondrial diseases are relatively common serious conditions with likely large medical and social costs to patients, carers and government, there is no microsimulation model of the impacts of this condition. Further, there is relatively little data on the medical costs of mitochondrial diseases and almost no data on social costs. What data there is on health costs has serious limitations and costs may be significantly underestimated. We aim to address this gap with the development of a microsimulation model called MitoMOD to estimate the costs of mitochondrial diseases using a cohort of clinically diagnosed adult patients with mitochondrial diseases as the base population. In this paper, we describe the construction of MitoMOD which is designed to capture economic impacts on adults clinically diagnosed with mitochondrial diseases, their carer and government. To date, this is the first microsimulation model of its kind.

This article contains 1 figure and 4 tables.

Figures

**Figure 1.** MitoMOD Microsimulation Model

Tables

Table 1. Study Participant’s Descriptive Statistics

	Frequency	Percent
Participant’s Age
18-30	7	7.3
31-44	23	24.0
45-60	29	30.2
61-74	27	28.1
75 and over	10	10.4
Participant’s Gender
Female	61	63.5
Male	35	36.5
Number of Participants with a Carer
No Carer	69	73.4
Patient Has a Carer	25	26.6
Number of Participants Partnered
Not Partnered	38	40.0
Partnered	57	60.0
Number of Participants Whose Spouse is the Carer
The Participant’s Spouse is not the Carer	41	71.9
The Participant’s Spouse is the Carer	16	28.1

Table 2. Descriptive Statistics of the Carers in EPIC-MITO

	Frequency	Percent
Carer’s age
30-44	2	8.3
45-60	7	29.2
61-74	8	33.3
=>75	7	29.2
Carer’s Gender
Female	14	58.3
Male	10	41.6
Number of Carers that are Partnered
Not Partnered	2	8.3
Partnered	22	91.7
Number of Carers that live with the Participant
Lives with the Participant	21	87.5
Does not live with the Participant	3	12.5

Table 3. Cost and sources used in MitoMOD

Item	Assigned cost (annual unless otherwise specified)	Perspective
Health care
Inpatient	AR-DRG (Linked data)	Government
Emergency department	URG (Linked data)	Government
Alternative medicines and services	Self-reported	Private
Healthcare services and treatments, pharmaceutical drugs, outpatient consultations	MBS and PBS Medicare (Linked data)	Government and Patient
Travel costs, meals, accommodation relating to hospital visits	Self-reported	Patient
Special diets, remedies, and OTC medication	Self-reported	Patient
Accommodation
Residential care	$16,973. Income and assets mean tested (for those earning no more than $$27,754 per year)	Government and Patient
Residential care - basic daily fee	$18,038
Respite care (in-home and out-of-home)	$13,024
Public housing	25-30% less than market rent
Welfare
Age pension, Disability pension, Youth allowance, Newstart (Unemployment benefit), Department of Veteran’s Affairs (DVA) pension, Parenting payment, Mobility allowance, AuStudy, Family Tax Benefit, Rent assistance, Carer Payment, Carer allowance, Sickness benefit, Other	Self-reported or estimated based on rates retrieved and methods for income and asset testing from Services Australia	Government, Patient and Carer
Employment
Patient’s employment	Self-reported or synthetically matched to estimate what they could have earnt if they did not have Mito or had to care for the patient	Government, Patient and Carer
Patient’s spouse employment
Carer’s employment
Carer’s spouse employment
Assistive technologies, modifications to home or car, transport subsidy
Assistive technologies: Walking aids/crutches, standard wheelchair, electric wheelchair, electric mobility scooter, visual aids (includes glasses), lifting devices, rails, hearing aids, orthotics/special shoes, others	Self-reported	Government and Patient
Home Modifications: Stairs, external areas, hallways/entrances, kitchen, living room, rails, bedroom/s, bathroom/s, other home modification
Car modification
Transport Subsidies: Bus service, taxi transport subsidy scheme, other

Table 4. Estimated population with MITO in the General Population and the estimated number in MitoMOD by Age and Sex

Age Group	Females				Males
Age Group	No. in our study*	No. in General Population†	Estimated No. with MITO in the general population	Weighted Estimate - Develop MITO	No. in our Study*	No. in the General Population†	Estimated No. with MITO in the General Population	Weighted Estimate - Develop MITO
18-44	17	4,596,124	18,384	10,873	13	4,607,904	18,432	14,083
45-59	19	2,440,246	9,761	12,152	7	2,348,074	9,392	7,583
60-84	25	2,717,076	10,868	15,989	15	2,522,983	10,092	16,250
Total	61	9,753,446	39,014	39,014	35	9,478,961	37,916	37,916

Based on current available dataset.

Source: Australian Bureau of Statistics(Australian Bureau of Statistics, 2021)

Note that the youngest age group is relatively under-represented due to the long diagnostic odyssey resulting in delay in diagnosis that patients with MITO face.