Economic Burden of Huntington’s Disease: Analysis from a Brazilian Tertiary Care Perspective

Abstract

Background:

Huntington’s disease (HD) exerts significant impacts on individuals and families worldwide. Nevertheless, data on its economic burden in Brazil are scarce, revealing a critical gap in understanding the associated healthcare costs.

Objective:

This study was conducted at a tertiary neurology outpatient clinic in Brazil with the aim of assessing annual healthcare service utilization and associated costs for HD patients.

Methods:

We conducted a cross-sectional observational study involving 34 HD patients. A structured questionnaire was applied to collect data on direct medical costs (outpatient services, medications), non-medical direct costs (complementary therapies, mobility aids, home adaptations), and indirect costs (lost productivity, caregiver costs, government benefits) over one year.

Results:

Significant economic impacts were observed, with average annual direct medical costs of $4686.82 per HD patient. Non-medical direct and indirect costs increased the financial burden, highlighting extensive resource utilization beyond healthcare services. Thirty-three out of 34 HD patients were unemployed or retired, and 16 relied on government benefits, reflecting broader socioeconomic implications. Despite the dataset’s limitations, it provides crucial insights into the economic impact of HD on patients and the Brazilian public health system.

Conclusions:

The findings underscore the urgent need for a more comprehensive evaluation of the costs to inform governmental policies related to HD. Future research is needed to expand the data pool and develop a nuanced understanding of the economic burdens of HD to help formulate effective healthcare strategies for patients.

Keywords

Huntington’s disease health care costs Brazil health expenditures socioeconomic factors neurodegenerative diseases health economics

INTRODUCTION

Huntington’s disease (HD) is a hereditary neurodegenerative disorder produced by a mutation of the Huntingtin gene (HTT) and is characterized by a constellation of motor, cognitive, and psychiatric symptoms. 1 It typically affects adult patients, with onset ages ranging widely from 30 to 50 and disease durations of 17 to 20 years.2,3, 2,3 The disease’s impact extends beyond the individual, affecting entire families and highlighting its significant societal implications.4,5, 4,5

This condition severely impairs patients’ quality of life and imposes a substantial caregiving burden on families and healthcare systems worldwide.4 –6 The prevalence of HD exhibits regional variations, with lower rates in Asian populations and a peak in North America. 7 In Brazil, where official prevalence data are scarce, estimates from the Brazilian Huntington’s Disease Association (ABH) indicate that there are between 14,700 and 21,000 carriers of the mutant gene. 8 Prevalence rates in Brazil differ by region, with reports indicating 1.85 cases per 100,000 in Rio Grande do Sul (southern part of the country), 7.2 cases per 100,000 in Minas Gerais (southeastern part of the country), and notably, 1 case per 1,000 in Alagoas (northeastern part of the country).9 –11

Despite its relative rarity, the condition has broad societal and economic implications. 12 Its association with various non-neurological symptoms underscores the need for a multidisciplinary and integrated care approach to improve quality of life and reduce premature mortality.13,14, 13,14 The financial strain on healthcare systems is notable. For instance, studies in the United Kingdom have estimated the annual cost per diagnosed individual at £21,605 UK pounds in 2016, which is approximately $31,243.33 when adjusted to 2022’s currency rates in US dollars. 15 In the United States, the costs for early and advanced stages of the disease were reported as $5,368.50 and $24,473.76, respectively. 12 The costs are presented in values for the year 2022, assuming an estimated annual inflation rate of 2%.

The lack of information on the socioeconomic impact of HD in Brazil is worrying, particularly due to healthcare resource constraints of the country. 16 This gap highlights the urgent need for comprehensive studies to quantify HD’s economic and social repercussions in Brazil. By focusing on healthcare service utilization and the direct/indirect costs, this study aims to provide essential insights for healthcare policy and resource allocation, ultimately improving the quality of life for those affected by Huntington’s Disease in Brazil.

MATERIALS AND METHODS

Study design and participants

We adopted a cross-sectional observational study design to evaluate the economic impact of HD in Brazil. The study was conducted at the tertiary neurology center of Escola Paulista de Medicina (School of Medicine) of Universidade Federal de São Paulo (UNIFESP) in São Paulo, Brazil.

A total of 34 patients were recruited from the hospital patient registry between August 2021 and September 2022. Inclusion criteria were: 1) motor and/or behavioral-cognitive symptoms and a confirmed diagnosis of HD based on genetic testing (presence of≥36 CAG repeats in the HTT gene); and 2) 18 years of age or older. Patients were excluded from the study if they did not have a confirmed result from genetic testing by the time of data collection. All recruited patients fulfilled the inclusion criteria.

Data were collected using a structured questionnaire, supplemented with additional material, during regular outpatient visits. The questionnaire, crafted from existing cost and healthcare utilization studies, aimed to document the economic impact of the condition.17,18, 17,18 It consisted of five sections: 1) Direct Medical Costs, covering outpatient, private consultations, and medications; 2) Direct Non-Medical Costs, for complementary treatment expenses; 3) Indirect Costs, detailing government benefits to patients; 4) Out-of-Pocket Expenses, including patient-paid medication, mobility aids and caregivers; 5) Sociodemographic Data, gathering age, gender, financial situation, and employment status information. This design, primarily using close-ended questions, facilitates precise quantitative analysis.

All participants received a comprehensive explanation of the study’s purpose before giving their informed consent. When cognitive or functional impairments prevented patients from directly communicating, we obtained responses and consent through their caregivers. To mitigate recall bias, we requested cost-related information for the preceding six months, then extrapolated this data to estimate annual expenses. All costs were calculated for a one-year period and reported in US dollars for the year 2022, providing a standardized currency basis for international comparison.

Cost analysis

The cost analysis was conducted from both the patient and public health system perspectives. To determine the direct medical and non-medical expenses, data were sourced from publicly available records of the Brazilian Public Health System (PHS), in Portuguese, Sistema Unico de Saude (SUS; http://aplicacao.saude.gov.br/bps and http://sigtap.datasus.gov.br). In the case of medicines directly purchased from pharmacies, we estimated the prevailing market rates at the time of the study, while fees for consultations with private therapists were directly obtained from the participants. Direct medical costs encompassed expenses associated with medications and consultations, whether acquired privately or through SUS, whereas direct non-medical costs included expenses for private and PHS-provided therapies, caregiver services, home modifications, and the need for mobility aids. The summation of all medical and non-medical expenses yielded the total direct costs. Indirect costs were derived from reported benefits, where available, and accounted for the lost income of caregivers who ceased employment to provide patient care, reflecting their diminished productivity.

Government benefits are classified as indirect costs because they provide financial support to households impacted by HD, rather than directly covering medical expenses. 19 These benefits, such as disability allowances and social security payments, compensate for the loss of income due to the patient’s inability to work or the caregiver’s need to reduce work hours.20,21, 20,21

Statistical analysis

Descriptive statistics were used to summarize patient demographics, healthcare utilization, and cost data. Mean and standard deviation (SD) were calculated for continuous variables, while frequencies and percentages were used for categorical variables.

A generalized linear model with Gamma distribution and inverse link function was employed. The Generalized Linear Model (GLM) extends traditional linear models such as linear regression. While linear regression assumes the response variable to follow a normal distribution, GLM allows the response variable to follow different distributions, thus better adapting to the data’s nature.

The selection of this approach is justified by the flexibility offered by the class of generalized linear models, allowing the population mean to be dependent on a linear predictor through a nonlinear link function. Additionally, this class permits the probability distribution of the response variable to be any member of the exponential family, which includes the Normal, Binomial, Poisson, and Gamma distributions. 22

The economic burden of HD was analyzed by calculating the total annual costs incurred by patients and the health system. All statistical analyses were performed using SPSS version 26.0 (IBM Corp., Armonk, NY, USA).

Ethical considerations

The study protocol was reviewed and approved by the Institutional Review Board (IRB) of Escola Paulista de Medicina, UNIFESP. All participants provided written informed consent prior to enrollment in the study. In cases where the patients were unable to respond due to the severity of their condition, caregivers fulfilled the questionnaire on their behalf, ensuring that the study’s inclusion criteria were met and maintaining the integrity of the data collected. This research was conducted in accordance with the Declaration of Helsinki and local regulatory requirements.

RESULTS

The study included 34 participants, with an average age of 48.2 years (range: 21 to 75 years). The age groups were well-represented, with 32.4% (11 patients) below 45 years, 26.5% (9 patients) aged between 45 and 49, 29.4% (10 patients) between 50 and 59, and 11.8% (4 patients) aged 60 and above. Among those interviewed, 11 responded directly to the survey, while 23 had assistance from their caregivers. Employment status revealed that the majority were unemployed (21 patients, 61.8%), followed by retirees (12 patients, 35.3%), and only 1 patient (2.9%) was employed at the time of the research. The gender distribution showed a predominance of female patients, constituting 20 participants (58.8%). Educational attainment varied among participants. Twelve (35.3%) completed primary education, seventeen (50.0%) completed secondary education, and five (14.7%) held advanced degrees or graduation certificates (Table 1).

Table 1

Demographic characteristics

Characteristic
Age, Years
Mean (SD)	48.2 (9.75)
Median [Min, Max]	47.5 [21.0, 75.0]
Age group, n (%)
<45	11 (32.4%)
45 a 49	9 (26.5%)
50 a 59	10 (29.4%)
60+	4 (11.8%)
Current employment, n (%)
Retired	12 (35.3%)
Unemployed	21 (61.8%)
Employed	1 (2.9%)
Gender, n (%)
Female	20 (58.8%)
Male	14 (41.2%)
Education Level, n (%)
Primary education	12 (35.3%)
Secondary education	17 (50.0%)
Advanced (graduation)	5 (14.7%)

SD, standard deviation; Min, minimum; Max, maximum.

In our analysis of medication patterns, we observed a varied prescription landscape among participants. Neuroleptics emerged as the most frequently used medication class, with 67.6% of patients receiving these drugs. Haloperidol was notably prevalent within this category. Following neuroleptics, antidepressants were used by 20 patients (58.8%) of the cohort. Antiparkinsonian medications, such as biperiden and amantadine, were used by 15 (44.1%) of participants, indicating its role in addressing motor symptoms. Conversely, the use of hypnotics and cannabinoids was reported by a smaller fraction of the study population, each by one patient, suggesting these treatments are less commonly pursued in our cohort. For a detailed breakdown of medication use, including specific drugs and their prevalence rates, please refer to Supplementary Table 1.

All 34 participants reported having medical consultations in the last six months, with 17 patients (50%) using additional healthcare services besides the outpatient clinic in the same period. Regarding complementary treatments, dental care was accessed by 10 patients (29.4%). In contrast, only 1 (2.9%) of individuals sought guidance from an educator in physical fitness, indicating a relatively low engagement. Physical therapy was more commonly utilized (11 patients, 32.4%), along with speech therapy (7 patients, 20.6%), and psychological support (5 patients, 14.7%). Lastly, 6 participants (17.6%) engaged in occupational therapy, indicating the recognition of the need for assistance with activities of daily living. 20 Eight patients (23.5%) had to make alterations to their environment due to HD, primarily installing handrails (5 responses). Concerning mobility and assistive equipment, 12 patients (35.3%) reported the need for a wheelchair.

Among the 34 individuals surveyed, only 4 (11.8%) did not have caregivers. Of the remaining 30 individuals (88.2%), most had family members as caregivers (20 patients, 58.8%), while professional caregivers were identified in 5 cases.

The detailed breakdown of annual costs associated with HD is presented in Table 2, shedding light on the economic impact on both patients and the healthcare system.

Table 2

Annual costs associated with HD, (US Dollar, year 2022)

Costs	Mean	95% CI^a	Minimum	Maximum
	(US$)	(US$)	(US$)	(US$)
Direct Medical costs
Cost os SUS^b medications	46.84	33.28–79.03	0.00	166.09
Private medication costs	270.34	176.57–576.47	0.00	1,396.16
Cost of SUS^b medical visits	8.73	6.56–13.06	4.01	32.10
Cost of private medical visits	22.42	9.02 - NE^c	0.00	481.43
Total	348.33	241.92–621.82	4.01	1,881.61
Direct nonmedical costs
Costs of SUS^b therapies	149.56	87.13–527.48	0.00	1,640.89
Private therapies costs	119.27	51.35 - NE	0.00	2,607.77
Cost of private caregiver services	706.58	416.71–2,321.06	0.00	4,814.35
Cost of private home adaptations	55.81	31.39–251.18	0.00	401.20
Cost of private mobility equipment	16.52	8.02 - NE	0.00	200.60
Total	1,047.74	669.86–2,403.65	0.00	6,940.68
Total direct costs	1,396.07	934.94–2,755.16	4.01	7,743.08
Indirect costs
Cost of government benefits	2,016.36	1,392.55–3,652.58	0.00	8,906.54
Cost of caregiver loss of productivity	1.274.39	820.11–2,856.85	0.00	7,221.52
Total	3,290.75	2,388.42–5,288.80	0.00	13,720.89
Total cost	4,686.82	3,743.24–6,266.42	20.0	14,362.80
Total cost, excluding caregiver loss of productivity	3,412.43	2,653.17–4,780.46	20.0	9,548.46

^a95% CI estimated by generalized linear model with Gamma distribution; costs of 0 were replaced with 0.01 for model adjustment. ^bSUS, Sistema Unico de Saude (public health system); ^cNE not estimated.

Direct costs

Patients faced significant expenses for medical services and medications, encompassing SUS Brazilian Public Health System (PHS) and private healthcare resources. The annual mean cost of medications provided by the PHS (not paid by the patients) was $46.84 (CI $33.28–$79.03), illustrating a broad range that highlights the diverse pharmaceutical needs among individuals with HD. Private medication costs averaged $270.34 (CI $176.57–$576.47), emphasizing the financial strain associated with privately obtaining essential medications. Additional costs related to PHS and private medical visits, at $8.73 and $22.42, respectively, further contributed to the overall economic impact. Nonmedical expenses, including therapies, caregiver services, home adaptations, and mobility equipment, represented a substantial portion of the economic burden. The mean costs of PHS therapies and private therapies were $149.56 and $119.27, respectively, illustrating the financial implications of seeking therapeutic interventions. Private caregiver services, with a mean cost of $706.58, underscored the considerable financial investment in caregiving. Costs associated with home adaptations ($55.81) and mobility equipment ($16.52) reflected additional direct nonmedical expenditures. The aggregate of direct medical and nonmedical costs averaged $1,396.07, with a considerable range ($4.01 to $7,743.08), emphasizing the multifaceted economic impact on HD patients.

Indirect costs

Indirect costs, including government benefits and caregiver loss of productivity, contributed significantly to the overall financial impact. Government benefits, a vital support mechanism, had a mean cost of $2,016.36, underscoring the financial assistance provided to HD patients. The cost of caregiver loss of productivity, averaging $1,274.39, highlighted the indirect economic burden shouldered by caregivers. The combined indirect costs, with a mean of $3,290.75, reflected the comprehensive financial impact beyond direct medical and nonmedical expenses.

Total costs

The overall mean total cost, encompassing direct and indirect expenses, amounted to $4,686.82, emphasizing the substantial economic burden on patients and the healthcare system. Excluding caregiver productivity costs, the mean total was $3,412.43.

The average annual costs associated with services provided by PHS were US$205.13, mainly comprising medication and healthcare services costs.

Sixteen individuals (47.1%) were beneficiaries of permanent government assistance, such as disability retirement. The average yearly sum received was $2,016.36, with a 95% confidence interval ranging from $1,392.55 to $3,652.58.

We carried out an analysis exploring the relationship between costs and age groups, uncovering unique economic trends associated with HD that vary by age category (Supplementary Table 2). Considering the overall economic impact, including both direct and indirect costs, individuals aged less than 45 years had a mean total cost of $3,904.55, those aged 45 to 49 years incurred $4,968.29, and individuals aged 50 to 59 years faced costs of $4,642.35. The mean total cost was $6,315.8 for participants aged 60 years and older.

These findings elucidate the age-specific economic intricacies of HD, providing valuable insights for targeted healthcare strategies.

DISCUSSION

This study explores the economic impact of HD within the specialized setting of the Neurology outpatient clinic at Escola Paulista de Medicina (UNIFESP), being the first exploration of HD-related costs and healthcare utilization in Brazil. Recognizing the diversity in methodologies and outcomes among previous studies on HD costs is essential.12,13,15,18,23–30 , 12,13,15,18,23–30 The lack of a unified, validated approach to cost assessment has led to significant variations in findings, emphasizing the need for our investigation.

When contrasting our data with findings from Peru and China, notably differences emerge in the economic burdens of HD, attributed to discrepancies in healthcare systems and treatment availability.18,23, 18,23 The unavailability of Tetrabenazine in Brazil during our study period might have influenced our medication use patterns, highlighting a key divergence from global practices. 31 Furthermore, the medication costs for HD in Brazil are relatively low compared to other countries such as the US and European nations. For instance, studies have shown that the annual cost of medications for HD patients in the US can be significantly higher.12,15,24 , 12,15,24

Age-stratified analysis offers deeper insights into the economic dynamics of HD, showing an increase in direct medical costs with age, peaking for those aged 60 and above. This trend aligns with HD’s progressive nature, which demands more specialized care and medications for older patients.23,24, 23,24 However, our analysis lacked data on disease severity or symptom duration, limiting our ability to fully explore cost variations across different disease stages.

Medication expenses are a significant factor in the overall costs of HD, accounting for 91% of direct medical costs. The absence of Tetrabenazine in Brazil notably influenced our findings, contrasting with global prescription patterns, such as in Israel, where tetrabenazine, benzodiazepines, and amantadine are most commonly prescribed.23–25,31 , 23–25,31 Additionally, within the scope of direct costs, both medical and non-medical, caregiving costs represent 51% of the total direct costs, indicating a major financial component in the management of HD.

The study from Peru presents an in-depth view of HD’s cost implications in developing countries, revealing an average annual cost of $8,617.01 (estimated annual inflation rate of 2%) — significantly higher than our findings in Brazil ($4,686.82). 18 The difference in values may be attributed to the Peruvian study considering certain costs not included in the present analysis, such as primary care, inpatient care, diagnostic tests, and transportation. Despite these differences, both studies concur on the major economic strain HD places on families, highlighting the critical need for comprehensive government health policies.

Our research uncovered the lowest annual cost value among all reviewed literature, including data from Italy, Spain, Germany, France, the United States, the United Kingdom, and Canada, where costs range from $4,167 Euros ($4,510.36 US dollars) in France to $30,029.02 in the US.28,29, 28,29 This may indicate that people in Brazil might not be receiving all the necessary services and care due to limitations in the healthcare system and economic constraints. Additionally, this observation must be understood in the context of the significant per capita income disparity between Brazil and the US. For example, the average annual per capita income in Brazil is significantly lower than that in the US, affecting the affordability and accessibility of comprehensive healthcare services. 32 Moreover, healthcare access and quality are significantly different between the two countries, with Brazil having lower performance on the Healthcare Access and Quality Index. 33 Moreover, the cost of labor services, including caregiving, also differs greatly between the two countries, further contributing to the lower reported costs in Brazil. 34 These factors highlight the complex financial challenges HD patients face in Brazil, covering medication expenses, therapeutic interventions, and caregiver services. The significant role of indirect costs, such as government benefits and caregiver productivity loss, further illustrates HD’s broad socioeconomic repercussions.27,35, 27,35

The findings emphasize the critical need for robust financial protection against healthcare expenses in lower-income settings. The work by Bolongaita et al. aligns with our observations, showcasing the financial vulnerability of patients to catastrophic health costs. 35 This reinforces the call for health policies that ensure equity and sustainability within healthcare systems.

Our comprehensive analysis at the Neurology outpatient clinic of EPM/UNIFESP aimed to illuminate the financial burdens HD imposes on patients, paving the way for future healthcare interventions and policies. Notably, direct costs per HD patient amounted to $1,396.07, reflecting the substantial resources required for HD management within the public health system and highlighting the importance of targeted resource allocation.

The considerable variation in costs across different age groups suggests the need for personalized treatment strategies. Direct non-medical costs related to caregiver services, home adaptations, and mobility aids underscore the multidisciplinary care necessity for HD patients. The high indirect costs call for enhanced social policies to support patients and caregivers, emphasizing government benefits’ crucial role.

This study has limitations, such as its single-center focus, the limited number of patients, and the absence of detailed clinical information on disease severity and progression, we advocate for broader research to deepen our understanding of HD’s economic and emotional toll. Future studies could explore the disease’s impact more comprehensively by including a wider range of disease severity stages, detailed clinical data, and socioeconomic factors. This would provide a more nuanced understanding of the costs associated with Huntington’s Disease and better inform healthcare strategies and policies.

In conclusion, the urgent need for individualized care and comprehensive health policies to tackle economic challenges is clear. By addressing the significant financial burden on patients and their families, we can enhance the quality of life for those affected by HD in Brazil and globally.

Footnotes

ACKNOWLEDGMENTS

The authors express gratitude to the patients and caregivers involved in this study, the staff at the tertiary neurology Centre of Escola Paulista de Medicina, Universidade Federal de São Paulo (UNIFESP), for their assistance, and the UNIFESP Ethics Committee for their endorsement.

Special thanks to Tony Piha for the manuscript revisions.

FUNDING

The authors have no funding to report.

CONFLICT OF INTEREST

The authors declare that they have no conflicts of interest concerning this publication.

DATA AVAILABILITY

The database created and analyzed for this study are available from the corresponding author on reasonable request.

The supplementary material is available in the electronic version of this article: .

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