Assessment of the Lifetime Costs of Severe Visual Impairment Due to Retinitis Pigmentosa

Introduction

Retinitis pigmentosa (RP) comprises a heterogeneous group of inherited retinal diseases (IRDs) characterized by progressive degeneration of retinal photoreceptors that in turn leads to progressive visual decline. Typical manifestations include nyctalopia, concentric visual field loss, and ultimately bilateral central vision loss.¹ The most common type of inherited retinal dystrophy, RP, represents a significant burden to both patients and society. It is one of the leading causes of visual disability and blindness in people under the age of 60 and affects more than 1.5 million people worldwide. RP is associated with multiple genetic mutations and affects about 1 in 4,000 people in the US.^2,3

For most people living with an IRD such as RP, there are currently no effective treatments. To date, only a small number of patients are eligible to receive voretigene neparvovec-rzyl, the first gene therapy approved by the U.S. Food and Drug Administration (FDA) in 2017 to treat an inherited genetic disease. Voretigene neparvovec-rzyl is administered by subretinal injection to patients with confirmed biallelic RPE65-mediated IRD and sufficient viable retinal cells.⁴

Lack of consistent data, as well as the underdiagnosis and misdiagnosis of IRDs, has resulted in few studies that clearly identify and describe the burden and impact of IRDs. Blindness is known to be associated with significant lifetime costs as well as lost productivity and reduced quality of life (QoL) for both patients and caregivers. Individuals who live with vision impairment often have related comorbidities.⁵ Some literature suggests that individuals living with visual impairment tend to have an increased risk of developing depressive symptoms.⁶ In one study, members of a community group comprising individuals with reduced vision were 1.6–2.3 times more likely to self-report symptoms of depression compared with a group in which no members had visual impairment after controlling for numerous demographic and lifestyle characteristics.⁷

Because IRDs such as RP typically manifest during childhood, the disease has lifelong implications for affected children and their families.⁵ An effective gene therapy for RP could offer substantial lifetime benefits for patients who might otherwise have no hope of a cure or meaningful visual improvement.⁸ Assigning value to such a therapy, which typically has significant upfront costs, is an important current focus of payers (and government entities) who must compare paying a larger price for a (typically one-time) treatment at an early stage of disease with paying repeatedly (over years/decades/a lifetime) for the consequences of a lifelong illness.⁷ By quantifying the lifetime cost burden associated with RP-related disability, this study can inform future cost-effectiveness assessments of vision-preserving therapies.

Methods

Study Design

An actuarial model was developed to estimate the present value of lifetime excess costs associated with blindness and subsequent disability due to RP. The actuarial model projects future direct and indirect costs incurred by disabled patients by considering factors such as the time value of money, mortality, and benefit eligibility based on age, employment status, income, and disability status. To assess the financial impact of disability due to RP, these lifetime costs are then compared to projected future direct and indirect costs incurred by the same individuals in the absence of disability. While many people with visual impairments continue working in some capacity or return to work with accommodations, this analysis assumes patients who become disabled due to RP do not to engage in gainful activity, which simplifies the analysis by aligning the disability onset with eligibility for long-term disability benefits and public assistance programs.

Lifetime costs estimates were developed for: 1) all-cause medical and pharmacy services (including long-term care and non-emergency transportation), based on analysis of administrative claims data, 2) Social Security and disability benefits, derived from a proprietary actuarial model and literature, 3) lost income and lost retirement income opportunity, and 4) supportive services. Mortality decrement and discount rate adjustments were applied to convert all lifetime costs to present values. A summary of the key assumptions of the actuarial model is provided in Table 1.

Table 1 Model Input Assumptions

Lifetime costs were estimated for three archetype individuals with RP becoming disabled before retirement age at 67.²⁸ For the purpose of modeling, each archetype was assumed to meet Social Security’s definition to receive disability benefits; that is their disability was due to permanent and uncorrectable vision acuity of less than 20/200 and inability to engage in sustained gainful activity. For simplicity, we also assumed that the patients received no other forms of income from employment (although the Social Security Administration does allow for patients to earn some income – up to a cap – while still receiving disability income).¹⁰ The three patient archetypes modeled were:

• Archetype #1: an actively employed 50-year-old with an annual income of $70,000;⁹
• Archetype #2: an actively employed 35-year-old with an annual income of $56,000; and
• Archetype #3: an unemployed 18-year-old with an annual income of $0.

Lifetime costs were estimated using administrative claims data for patients diagnosed with RP, disability and mortality data for blind individuals, and from literature on legal blindness. Lifetime costs for the three archetype individuals who become disabled were compared to those for the same individuals assuming no disability and continuous employment until retirement.²⁸ Lifetime costs for patients who never become disabled (“never disabled”) were derived from administrative claims data and disability and mortality tables for the general population. Sensitivity testing was performed on key inputs.

Because this study relied on secondary, de-identified data, ethics committee approval was not required.

All-cause medical and pharmacy, long-term care, and non-emergency medical transportation services.

Data Sources

Data sources for all-cause medical costs include the Centers for Medicare & Medicaid Services (CMS) Medicare 100% Research Identifiable Files (RIF), Milliman’s Consolidated Health Cost Guidelines Sources Database (CHSD), Merative MarketScan^® (Marketscan) Commercial Claims Database & Health & Productivity Management Database, and the Transformed Medicaid Statistical Information System (T-MSIS) data for years 2018–2019. We relied on the Data Quality (DQ) Atlas, a source governed by CMS, to remove states with poor Medicaid data quality submissions to T-MSIS from the analysis.²⁹ Illinois, Texas, Utah, the Virgin Islands and Puerto Rico were excluded as a result.

Patient Population

Patients with commercial and Medicare coverage in this study had 12 months of medical and pharmacy enrollment in 2019. Because of the volatility of Medicaid enrollment due to filing criteria, patients with Medicaid coverage were only required to have 10+ months of medical and pharmacy coverage in 2019.³⁰

We identified patients with RP as those with 2 or more non-diagnostic (excluding lab and pathology) medical claims, 30+ days apart, with International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) diagnosis codes H3550, H3552, and H3553 in any position incurred in 2019.³¹

Medical and Pharmacy Services

In the United States, working-age adults are generally covered by employer-sponsored commercial insurance, which is often lost following disability-related job separation. Medicaid provides coverage for individuals with low income or qualifying disabilities, while Medicare is a federal program available to adults aged 65 years or older and to younger individuals with permanent disability. To qualify for Medicare due to disability before attaining age 65, patients must meet minimum work credit requirements (about ten years of work) and a 24-month waiting period.

Accordingly, we have assumed patients with RP transition from commercial insurance to Medicaid immediately following disability-related job loss, with eventual Medicare eligibility following the waiting period when work credits are met, consistent with U.S. coverage pathways. For the 35-year-old and 50-year-old archetype patients becoming disabled with RP, we assumed commercial health benefits coverage in year one (year of disability), Medicaid in year two (after loss of employment), and Medicare from the third year onwards. For the 18-year-old archetype patient, we assumed Medicaid coverage until age 65 and Medicare thereafter. For the never disabled archetypes, we assumed commercial health benefits coverage until Medicare enrollment at age 65.

All-cause medical and pharmacy costs were estimated using 2019 administrative claims data from MarketScan (commercial), Milliman’s CHSD (Medicaid), and CMS RIF (Medicare) representing patients with commercial, Medicaid, and Medicare coverage, respectively. Annual average allowed amounts (paid by both payer and patient combined) were summarized separately for patients covered by commercial, Medicaid, and Medicare, and aggregated for each archetype based on the assumed health coverage until age 65. For the never disabled archetypes, medical and pharmacy costs for commercial health benefits were assumed through the age of 65. Costs were reported as average per patient per year (PPPY) by major service category: inpatient (acute and post-acute inpatient facilities), outpatient, and pharmacy.

Long Term Care and Non-Emergent Medical Transportation

Long-term care (LTC) refers to a variety of services designed to help people live as independently and safely as possible when they can no longer perform everyday activities on their own.³² LTC is often provided to older adults but can also be necessary for younger individuals with disabilities or chronic illness. Payments for LTC services usually come from the individual/family or, if the patient qualifies, Medicaid. Medicaid LTC services were estimated from the 2019 T-MSIS database. Claims for long-term care acuity levels Home & Community Based Services, Home Health, Intermediate Care for Mentally Retarded, and Skilled Nursing Facility were evaluated to calculate average allowed amounts PPPY.

Non-emergency medical transportation (NEMT) is a transportation benefit covered by Medicaid for eligible individuals and is required by federal regulation.^33,34 NEMT covers rides to and from doctor appointments, hospital visits, and other medical offices for Medicaid-approved care. In the case of RP, rides are provided due to a physical disability where the individual is unable to travel alone. Payments for NEMT are capitated in this market, however some states also use FFS reimbursements, vouchers, or a state-run transportation system. Average allowed amounts for NEMT services were calculated as PPPYs based on available claims in T-MSIS.

Medicaid-covered LTC and NEMT costs were estimated using T-MSIS data and were calculated separately for those with full Medicaid benefit coverage and for those dually eligible for both Medicare and Medicaid. Medicaid LTC and NEMT (per patient per year) PPPY levels were applied to patients under 65. After age 65, the dual eligible PPPY levels applied. Medicaid eligibility was assessed annually for each archetype and was defined as having an annual income lower than 138% of the poverty level. Historical poverty guidelines from the Health and Human Services (HHS) Data Council from 2023 were projected forward for the duration of our projection.³⁵

The 35-year-old archetype patient was projected to receive LTC and NEMT benefits only after retirement at age 67, based on projected income. The 50-year-old archetype patient is projected to never qualify for Medicaid. The 18-year-old archetype patient is projected to receive Medicaid LTC and NEMT benefits from the age of disability to age 65, where Medicare-dual coverage begins. The never disabled archetypes do not receive any LTC and NEMT benefits in this study, as they do not qualify for Medicaid at any point in the projections.

Risk Adjustment

To account for variations in the health status and characteristics of the archetype patients with disability and never disabled individuals, average medical and pharmacy, LTC, and NEMT PPPY amounts were risk adjusted by payer market.^32,33 For costs incurred by commercially insured and Medicaid enrollees, scores derived using the Department of Health and Human Services Hierarchical Condition Categories (HHS-HCC) 2019 model were used.³⁶ For costs incurred by Medicare beneficiaries, scores derived using the CMS Hierarchical Condition Categories (CMS-HCC) 2020 model used.^37,38

Social Security and Disability Benefits

Short-Term Disability, Long-Term Disability, and Social Security Disability Income

Short-term disability (STD) is an employer sponsored income replacement provided to disabled individuals. We estimated the cost for STD benefits for disabled patients with RP as 3 months of benefit payments replacing 60% of pre-disability income, which is the most common employer sponsored STD benefit.²⁵ For the never disabled archetype individuals, the estimated annual cost of STD was approximated as 2% of the individual’s salary and applied for three months of benefits. STD costs for the never disabled individuals were calculated and projected through retirement age.³⁸

Long-term Disability (LTD) is an employer sponsored income replacement that begins when STD benefits end and terminates once the individual reaches retirement age. LTD costs assume the disabled worker will be awarded SSDI benefits following a 5-month elimination period, and that SSDI benefits offset LTD benefits subject to a minimum LTD benefit amount equal to 10% of the gross benefit amount. This approach is consistent with how LTD and SSDI benefits are typically coordinated, and it is consistent with the assumption of no recoveries because SSDI benefits are typically awarded to workers who are totally disabled. LTD is assumed to supplement Social Security Disability Income (SSDI) to achieve a 60% pre-disability income replacement ratio. SSDI is a government sponsored disability benefit that is paid to individuals who are disabled and have a qualifying work history.³⁹

LTD benefits were assumed to begin when STD benefits ended and were terminated once the individual reached retirement age. For the archetype disabled patients with RP, we projected LTD and SSDI benefits to age 67, discounted by mortality. We assume zero probability of recovering from the disability in the actuarial model, as vision loss is irreversible. For the never disabled individuals, we calculated LTD as a cost to the employer for long-term disability insurance. LTD, like STD, is assumed to cost the employer 2% of the individual’s annual salary through retirement age.³⁷

Supplemental Security Income

The Supplemental Security Income (SSI) program provides financial assistance to adults and children with disabilities who have income and resources below a specified threshold, the Federal Benefit Rate (FBR).⁴⁰ In our model, the disabled individuals with RP are assumed to qualify for SSI based on their blindness.²³ A general income exclusion for unearned income was applied, which in our model included STD, LTD, and SSDI benefits.

Under this framework, the never disabled archetype individuals in our model do not qualify for SSI, as they exceed income thresholds. Additionally, the 35-year-old and 50-year-old archetype patients disabled with RP do not ever receive SSI benefits either, as their income exceeding the established threshold.

Supplemental Nutrition Assistance Program

The Supplemental Nutrition Assistance Program (SNAP) provides nutritional support for individuals and families with low incomes. In this model, only patients who qualify for Medicaid, and are receiving SSI benefits were assumed to receive SNAP benefits. SNAP benefits were trended forward to the projection years based on the 2022 average monthly SNAP benefit of $231.20, published by the United States Department of Agriculture (USDA).²⁶

Lost Income Opportunity

Wages Lost Due to Disability

Lost income opportunity (LIO) is an indirect cost associated with disability, representing wages lost due to inability to work that are not replaced by employer or government benefits. For the 35-year-old and 50-year-old patient archetypes with RP who become disabled, LIO was assumed equal to the 40% lost wages that are not replaced by LTD and SSDI benefits, until retirement age.²⁴ For the 18-year-old patient, who becomes disabled without qualifying for LTD and SSDI benefits, LIO represents estimated income lost due to inability to work, offset by SSI benefits received.⁴¹ Historical median annual earnings for individuals ages 18 through 34 were used in the model, trended for each year of the projection. The never disabled archetype individuals were assumed to participate in the workforce until retirement and therefore did not incur LIO.

Retirement Income Lost and Government Retirement Savings

Lost retirement income opportunity (LRIO) is an indirect cost that represents income lost due to lower earnings during the disability period. According to the Social Security Office of Retirement and Disability Policy, a replacement rate of 70% of pre-retirement income is adequate for retirement. To calculate LRIO, we projected the full annual LIO at retirement age and applied a 70% income replacement rate.²⁷ The never disabled archetype individuals were assumed not to incur LRIO due to full retirement earnings.

While the disabled archetype patients with RP experience a loss of retirement income due to an incomplete work history, the government incurs corresponding savings, as it no longer needs to pay retirement benefits for these individuals. To reflect the societal costs associated with disability due to RP, we reflect these savings in our study. Starting at age 67, government savings per year are assumed to equal LRIO.

Supportive Services

Informal Care

Informal care refers to uncompensated personal care assistance provided by family members or friends. To quantify the cost of informal care, we determined the hourly cost of informal care and then converted this to an annual value. According to caregiver.org, the average full-time worker requires 6.6 days of informal care per year.¹⁶ A study published in JAMA Ophthalmology found that individuals with blindness or some visual impairment require 5.2 excess informal care days per year in comparison to an individual who has no vision impairment.¹⁷ Therefore, we assumed archetype disabled patients with RP require 11.8 days of informal care per year (6.6+5.2), compared to 6.6 days per year for never disabled archetype individuals. We defined days of care as 16 hours, resulting in 105.6 and 188.8 hours of informal care per year for the disabled and never disabled archetype patients, respectively.

To estimate annual costs driven by days of informal care, we assumed a median annual salary of $30,844 for a home health aide, based on the 2022 reported median annual salary, trended to 2023.¹⁸ Assuming a 40-hour workweek, we calculated that $14.83 hourly rate for home health aide services. Consequently, the estimated annual cost of informal care is $2,800 for disabled archetype patients with RP, and $1,566 annually for never disabled archetype individuals. We assumed annual cost of informal care will be incurred by disabled archetype patients with RP from the onset of their disability and by never disabled archetype patients starting at age 75.

Supportive Services

Supportive services as defined by the Centers for Disease Control and Prevention (CDC) in its Vison Loss Economic Explorer encompass the costs associated with several federal programs, school vision screening programs, special education services, and various vision rehabilitation assistance services.¹⁹ These programs provide adapted books and textbooks for individuals with low vision or blindness, early identification of eye disorders, educational services for youth and young adults, intervention programs, guide dogs, and various other support services aimed at enhancing the lives of those experiencing vision loss. The CDC breaks out the cost of these services by age group and gender for, ages 0–18, ages 19–64, and ages 65+.

We applied a blended annual cost (for males and females), in 2023 dollars, to each year following disability for the disabled archetype patients with RP, according to their age group. The total annual supportive service costs were $1,555 for ages 0–18, $199 for ages 19–64, and $627 for ages 65+. Supportive service costs, as defined by the CDC, were not assumed to be incurred by never disabled archetype individuals.

Non-Medical Transportation

Patients who are legally blind have transportation needs beyond NEMT due to their inherent inability to drive. To estimate the transportation cost for patients disabled with RP, we relied on fixed route paratransit cost for all transportation services. The annual paratransit costs were estimated as $12.25 per fixed route trip, as reported by the United States Government Accountability office,²¹ adjusted to 2023 dollars, and multiplied by the number of trips per year. According to a Bureau of Transportation Statistics report, patients with visual impairment under age 65 take 2.3 daily non-medical trips, while those 65 and older take 2.1 non-medical daily trips.²⁰ The resulting annual transportation costs for the disabled patients with RP was $10,282 for those under age 65 and $8,494 for those 65 and older. For the never disabled individuals, the annual transportation costs were estimated by multiplying the annual miles travelled by household, or 12,295 (assuming 2 drivers per household)²² by the cost per mile, sourced from the Bureau of Transportation Statistics and adjusted to 2023 dollars, of $0.73. The resulting annual transportation costs for non-disabled individuals under 65 were $6,148.

Mortality Decrement Tables

We applied a mortality decrement to projected costs for each year of the projection following disability due to vision loss to account for the likelihood that not all individuals in a cohort will survive to the following year. For the never disabled archetype individuals, we relied on mortality rates from the Social Security Administration’s (SSA) 2020 Period Life Table, an actuarial life table used in the SSA’s 2023 Trustees Report,¹⁴ to calculate the probability of survival for each year of the projection. For disabled archetype patients with RP, we increased these survival probabilities by 1.54, based on the hazard ratio reflecting the increased mortality risk associated with vision impairment.¹⁵

Present Value

To project lifetime costs, annual cost estimates in 2023 were trended forward for each year of the projections. Medical and pharmacy services were trended by the average medical Consumer Price Index (CPI) of 2.9%.¹³ All other costs were trended annually based on an average CPI of 2.2%.¹² These rates were based on the average of historical CPI data from 2008 to 2023, excluding 2020 and 2021 due to the impact of the COVID-19 pandemic. All costs were then discounted to represent the present value of future benefits. Based on 15 years of historical 30-year treasury bond rates from 2008 to 2023, excluding 2020 and 2021, we applied an annual 3.3% discount rate to all costs projected in this model.¹¹

Results

Archetype 1: Patient with RP Disabled at Age 50

The lifetime costs incurred by a patient following disability onset at age 50 were estimated to be $1,741,141, which was 236% higher than the expected costs for the individual should they have never become disabled. (Table 2) Excess costs for disability benefits paid by employers and government were estimated to be almost $560,000, and the patient was estimated to lose a total of over $405,000 in income. The cost to the patient is even higher when considering the almost $245,000 in lost retirement income. Although the lifetime costs of lost retirement income to the individual are offset by government savings (through lower benefits) when determining societal costs, the human impact is considerable.

Table 2 Lifetime Costs Beginning at Disability for Patient Disabled at Age 50

Archetype 2: Patient with RP Disabled at Age 35

The patient who becomes disabled at 35 illustrates a more costly scenario to society since disability begins at a younger age. The lifetime costs incurred by such a patient were estimated to be $2,586,819, 305% higher than the expected costs for the individual should they have never become disabled. (Table 3) Excess costs for disability benefits paid by employers and government were estimated to be over $780,000, and the patient was estimated to lose a total of over $565,000 in income (or over $720,000 when considering lost retirement income, which is offset in determining societal costs by government savings from retirement benefits).

Table 3 Lifetime Costs Beginning at Disability for Patient Disabled at Age 35

Archetype 3: Patient with RP Disabled at Age 18

The patient who becomes disabled at 18 illustrates the most severe of scenarios, indicating a patient is disabled before they can become actively and gainfully employed. The lifetime costs incurred by such a patient following disability were estimated to be $3,072,650, 300% higher than the expected costs for the individual should they have never become disabled. (Table 4) Disability benefits paid by employers and government are not a cost for this patient since they never gained active employment. Instead, the largest contributor to excess costs is lost income opportunity, estimated for this individual to be $1,442,276 (or $1,688,545 when considering lost retirement income, which is offset by government savings in retirement benefits).

Table 4 Lifetime Costs Beginning at Disability for Patient Disabled at Age 18

Sensitivity Testing

Sensitivity testing was performed on key inputs, including mortality rates, discount rates, and PPPY costs). We found that, while results fluctuate somewhat, modest changes in these assumptions did not change the conclusions. The key drivers of excess lifetime costs continued to be lost income and disability benefits in all scenarios.

Discussion

The costs summarized for the three patient archetypes in this study demonstrate considerable burden spread across employers, the government, and the patient (and their personal support). In every scenario, the patient bears the largest burden, ranging from 38% to 74% of total excess costs, via lost income and needs for supportive services. (Figure 1, Table 5) The burden to the patient is underestimated since, from a society-level perspective, lost retirement income is offset by savings from the government not paying out that income in retirement. Approximately one-third of excess costs are incurred by government programs when the patient is actively employed prior to disability. Since the 18-year-old individual is never actively employed, they are ineligible for disability benefits, so the government liability is smaller at 24%.

Table 5 Present Value of Excess Lifetime Costs Following Disability

Figure 1 Present Value of Excess Lifetime Costs Following Disability.

Gene therapies such as voretigene neparvovec-rzyl have the potential to reduce the lifetime cost associated with disability due to RP. However, such therapies typically have high upfront costs due to the complexity of their development, as gene therapies may, due to the genetic heterogeneity of RP, be personalized for each patient. As such, payers must make coverage decisions by comparing the large upfront costs of (often one-time) treatments at an early stage of the disease with the smaller but recurring costs associated with lifetime treatment for a worsening condition.⁸ However, payers lack appropriate tools to make those comparisons and are increasingly relying on assessments by independent organizations such as the Institute for Clinical and Economic Review (ICER).⁴²

Quality adjusted life years (QALYs) and recently evolved derivatives (such as the Equal Value of Life Years Gained (evLYG), Healthy Years in Total (HYT) and the Generalized Risk-Adjusted QALY (GRA-QALY) methods) are widely used in health economics and outcomes research to assess cost-effectiveness of healthcare interventions by assigning an economic value to each year of survival (adjusted for the quality of life). However, as demonstrated by this study, QALYs cannot capture the full economic picture of the disease, as they ignore societal preferences and individual needs.⁴³ For instance, QALYs assume that extending life by one year has the same value for everyone. QALYs would tend to underestimate the value of a cure for RP because the disease does not affect survival. Another limitation of QALYs is that the definition of quality of life is highly subjective and may vary greatly by country and even by sub-population. Last, QALYs tend to ignore benefits to society such as the impact to caregivers, both formal and informal and the societal benefits of improved quality of life. As this study demonstrates, societal costs such as social security and disability benefits, lost income opportunity, long term care, transportation, and dependent care services are major contributors to excess cost for patients with RP, despite being commonly ignored by QALYs.

This study uses a novel methodology to quantify the societal burden of RP-related disability due to blindness by assessing the lifetime costs of disability for three archetype patients. The actuarial model in this study captures costs borne by patients and their caregivers, employers, payers, and the government, providing a more comprehensive view of the burden of disease to society. The results of this study can further the understanding of the lifetime benefits of interventions with the potential to prevent disability, such as gene therapies for the treatment of RP.

Limitations

In the evaluation of the cost of all-cause medical services, the identification of patients with retinitis pigmentosa (RP) was based on administrative claims data from the year 2019. Notably, no medical records were used to characterize the patient cohorts in this study. As a result, variations in sources and time periods could potentially yield different results depending on the dataset utilized.

The outcomes of this analysis are also contingent upon the age at the onset of disability. The timing of disability onset is a critical determinant, as it may influence both the immediate and long-term healthcare needs, as well as the aggregated costs.

This model was designed to capture the most prevalent societal costs related to disability due to blindness; however, it is important to note that not all relevant costs were incorporated into the analysis. Excluded costs could be substantial over the lifetime of a patient with RP, suggesting that the total societal burden of the condition may be underestimated. Beyond financial measures, RP-related disability also has significant human consequences, including loss of independence, reduced quality of life, and increased risk of depression, which are not captured in the cost estimates.

Furthermore, while blindness due to RP does not inherently result in complete loss of employment, this model assumes that individuals cease working following disability onset, to model a clearly defined baseline that aligns with eligibility for long-term disability benefits and public assistance programs. If these individuals remain employed or gain employment post-disability, the associated costs and outcomes would likely differ, potentially altering the conclusions drawn from this analysis. We acknowledge that rapid advances in assistive technologies may further influence workforce participation and cost projections for patients with RP. Introducing partial employment scenarios, such as 50% earning capacity, would require strong empirical assumptions regarding wage replacement, job retention, benefit eligibility, and transitions across insurance and disability programs, for which robust, generalizable data specific to RP are limited.

All excess cost estimates in this study are calculated relative to a “never disabled” archetype, assumed to remain continuously employed until age 67. We acknowledge that the general population experiences periods of unemployment, health events, and other life circumstances that can reduce lifetime earnings. As a result, the baseline used for comparison could potentially overstate expected costs in the absence of disability, inflating the estimated excess costs associated with RP.

Conclusion

Traditional approaches that focus on direct medical costs to value burden of disease and potential therapies may not be applicable to an ophthalmic disease such as RP. Patients with RP often remain healthy and so do not accrue significant medical costs, yet vision loss leads to disability with profound lifetime economic and humanistic consequences. The present value of lifetime excess costs associated with RP-associated disability are $1,222,496, $1,948,063, and $2,303,667, for patients who become disabled due to blindness at ages 50, 35, and 18, respectively. This represents excess costs of 236%, 305%, and 300% compared to patients who do not have vision loss and are able to remain in the workforce until the normal retirement age. The main contributors to lifetime costs are lost wages and disability benefits; these costs far exceed direct healthcare costs for patients with RP-related disability. While the real-world impact of vision-preserving interventions will depend on therapy efficacy, timing of administration, and associated costs, these findings highlight the importance of incorporating long-term productivity and disability-related impacts when evaluating the societal value of vision-preserving treatments. This study also underscores the need for broader evaluative frameworks when considering high-cost, one-time therapies. The actuarial approach presented here can potentially be applied to other inherited retinal diseases or disabilities to estimate the long-term cost burden on individuals and society, aiding health policy decisions.