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The economic burden of inherited retinal disease in Singapore: a prevalence-based cost-of-illness study

Eye volume 37, pages 3827–3833 (2023)Cite this article

Subjects

Abstract

Objective

To assess the economic impact of inherited retinal disease (IRD) among Singaporeans.

Methods

IRD prevalence was calculated using population-based data. Focused surveys were conducted for sequentially enrolled IRD patients from a tertiary hospital. The IRD cohort was compared to the age- and gender-matched general population. Economic costs were expanded to the national IRD population to estimate productivity and healthcare costs.

Results

National IRD caseload was 5202 cases (95% CI, 1734–11273). IRD patients (n = 95) had similar employment rates to the general population (67.4% vs. 70.7%; p = 0.479). Annual income was lower among IRD patients than the general population (SGD 19,500 vs. 27,161; p < 0.0001). Employed IRD patients had lower median income than the general population (SGD 39,000 vs. 52,650; p < 0.0001). Per capita cost of IRD was SGD 9382, with a national burden of SGD 48.8 million per year. Male gender (beta of SGD 6543, p = 0.003) and earlier onset (beta of SGD 150/year, p = 0.009) predicted productivity loss. Treatment of the most economically impacted 10% of IRD patients with an effective IRD therapy required initial treatment cost of less than SGD 250,000 (USD 188,000) for cost savings to be achieved within 20 years.

Conclusions

Employment rates among Singaporean IRD patients were the same as the general population, but patient income was significantly lower. Economic losses were driven in part by male patients with early age of onset. Direct healthcare costs contributed relatively little to the financial burden.

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Data availability

All relevant data are included in the manuscript and Supplementary.

References

  1. Stone EM, Andorf JL, Whitmore SS, DeLuca AP, Giacalone JC, Streb LM, et al. Clinically focused molecular investigation of 1000 consecutive families with inherited retinal disease. Ophthalmology. 2017;124:1314–31.

    Article  PubMed  Google Scholar 

  2. Heath Jeffery RC, Mukhtar SA, McAllister IL, Morgan WH, Mackey DA, Chen FK. Inherited retinal diseases are the most common cause of blindness in the working-age population in Australia. Ophthalmic Genet. 2021;42:431–9.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  3. Liew G, Michaelides M, Bunce C. A comparison of the causes of blindness certifications in England and Wales in working age adults (16-64 years), 1999-2000 with 2009-10. BMJ Open. 2014;4:e004015.

    Article  PubMed  PubMed Central  Google Scholar 

  4. Russell S, Bennett J, Wellman JA, Chung DC, Yu ZF, Tillman A, et al. Efficacy and safety of voretigene neparvovec (AAV2-hRPE65v2) in patients with RPE65-mediated inherited retinal dystrophy: a randomised, controlled, open-label, phase 3 trial. Lancet. 2017;390:849–60.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  5. Fenner BJ, Tan TE, Barathi AV, Tun SBB, Yeo SW, Tsai ASH, et al. Gene-based therapeutics for inherited retinal diseases. Front Genet. 2021;12:794805.

    Article  CAS  PubMed  Google Scholar 

  6. Sanie-Jahromi F, Nowroozzadeh MH. RPE based gene and cell therapy for inherited retinal diseases: a review. Exp Eye Res. 2022;217:108961.

    Article  CAS  PubMed  Google Scholar 

  7. Bhadhuri A, Dröschel D, Guldimann M, Jetschgo C, Banhazi J, Schwenkglenks M, et al. Cost-effectiveness of voretigene neparvovec in the treatment of patients with inherited retinal disease with RPE65 mutation in Switzerland. BMC Health Serv Res. 2022;22:837.

    Article  PubMed  PubMed Central  Google Scholar 

  8. Jayasundera KT, Abuzaitoun RO, Lacy GD, Abalem MF, Saltzman GM, Ciulla TA, et al. Challenges of cost-effectiveness analyses of novel therapeutics for inherited retinal diseases. Am J Ophthalmol. 2022;235:90–7.

    Article  PubMed  Google Scholar 

  9. Johnson S, Buessing M, O’Connell T, Pitluck S, Ciulla TA. Cost-effectiveness of voretigene neparvovec-rzyl vs standard care for RPE65-mediated inherited retinal disease. JAMA Ophthalmol. 2019;137:1115–23.

    Article  PubMed  PubMed Central  Google Scholar 

  10. Uhrmann MF, Lorenz B, Gissel C. Cost effectiveness of voretigene neparvovec for RPE65-mediated inherited retinal degeneration in Germany. Transl Vis Sci Technol. 2020;9:17.

    Article  PubMed  PubMed Central  Google Scholar 

  11. Zimmermann M, Lubinga SJ, Banken R, Rind D, Cramer G, Synnott PG, et al. Cost utility of voretigene neparvovec for biallelic RPE65-mediated inherited retinal disease. Value Health. 2019;22:161–7.

    Article  PubMed  Google Scholar 

  12. Galvin O, Chi G, Brady L, Hippert C, Del Valle Rubido M, Daly A, et al. The impact of inherited retinal diseases in the Republic of Ireland (ROI) and the United Kingdom (UK) from a cost-of-illness perspective. Clin Ophthalmol. 2020;14:707–19.

    Article  PubMed  PubMed Central  Google Scholar 

  13. Gong J, Cheung S, Fasso-Opie A, Galvin O, Moniz LS, Earle D, et al. The impact of inherited retinal diseases in the United States of America (US) and Canada from a cost-of-illness perspective. Clin Ophthalmol. 2021;15:2855–66.

    Article  PubMed  PubMed Central  Google Scholar 

  14. Kessel L, Kjellberg J, Nissen K, Rasmussen A, la Cour M. Childhood-onset retinal dystrophies reduces life-time income by one third—an individual based socio-economic analysis. Ophthalmic Genet. 2022;43:602–8.

  15. Bertelsen M, Linneberg A, Rosenberg T. Socio-economic characteristics of patients with generalized retinal dystrophy in Denmark. Acta Ophthalmol. 2015;93:134–40.

    Article  PubMed  Google Scholar 

  16. Kessel L, Kjellberg J, Ibsen R, Rasmussen A, Nissen KR, la Cour M. Longitudinal analysis of health care costs in patients with childhood onset inherited retinal dystrophies compared to healthy controls. BMC Ophthalmol. 2022;22:466.

    Article  PubMed  PubMed Central  Google Scholar 

  17. Ong SE, Tyagi S, Lim JM, Chia KS, Legido-Quigley H. Health systems reforms in Singapore: a qualitative study of key stakeholders. Health Policy. 2018;122:431–43.

    Article  PubMed  Google Scholar 

  18. Teo CL, Cheung N, Poh S, Thakur S, Rim TH, Cheng CY, et al. Prevalence of retinitis pigmentosa in Singapore: the Singapore Epidemiology of Eye Diseases Study. Acta Ophthalmol. 2021;99:e134–5.

    Article  PubMed  Google Scholar 

  19. Lim HB, Tan TE, Fenner BJ, Heah J, Arundhati A, Khor WB, et al. Clinical operational considerations and responses to lockdown and reopening in the Covid-19 pandemic: experience of a tertiary ophthalmology centre in Singapore. Eye. 2022;36:1924–33.

    Article  CAS  PubMed  Google Scholar 

  20. Singapore Medical Council. Annual Report—2021. Singapore; 2021.

  21. Cochran WG. Sampling techniques. 3rd ed. New York: John Wiley and Sons; 1977.

  22. Majithia S, Tham YC, Chee ML, Nusinovici S, Teo CL, Chee ML, et al. Cohort profile: The Singapore Epidemiology of Eye Diseases study (SEED). Int J Epidemiol. 2021;50:41–52.

    Article  PubMed  Google Scholar 

  23. Hong R, Pang CE, Cai J. Population trends. Industry MoTa, ed. Republic of Singapore: Department of Statistics; 2021.

  24. Mihaylova B, Briggs A, O’Hagan A, Thompson SG. Review of statistical methods for analysing healthcare resources and costs. Health Econ. 2011;20:897–916.

    Article  PubMed  Google Scholar 

  25. Robson AG, Frishman LJ, Grigg J, Hamilton R, Jeffrey BG, Kondo M, et al. ISCEV standard for full-field clinical electroretinography (2022 update). Doc Ophthalmol. 2022;144:165–77.

    Article  PubMed  PubMed Central  Google Scholar 

  26. Blindness GBD, Vision Impairment Collaborators, Vision Loss Expert Group of the Global Burden of Disease Study. Causes of blindness and vision impairment in 2020 and trends over 30 years, and prevalence of avoidable blindness in relation to VISION 2020: the Right to Sight: an analysis for the Global Burden of Disease Study. Lancet Glob Health. 2021;9:e144–60.

    Article  Google Scholar 

  27. FFB. Member Survey for My Retina Tracker. 2020. https://www.fightingblindness.org/my-retina-tracker-registry.

  28. Botto C, Rucli M, Tekinsoy MD, Pulman J, Sahel JA, Dalkara D. Early and late stage gene therapy interventions for inherited retinal degenerations. Prog Retin Eye Res. 2022;86:100975.

    Article  CAS  PubMed  Google Scholar 

  29. Sainohira M, Yamashita T, Terasaki H, Sonoda S, Miyata K, Murakami Y, et al. Quantitative analyses of factors related to anxiety and depression in patients with retinitis pigmentosa. PLoS ONE. 2018;13:e0195983.

    Article  PubMed  PubMed Central  Google Scholar 

  30. Huygens SA, Versteegh MM, Vegter S, Schouten LJ, Kanters TA. Methodological challenges in the economic evaluation of a gene therapy for RPE65-mediated inherited retinal disease: the value of vision. Pharmacoeconomics. 2021;39:383–97.

    Article  PubMed  PubMed Central  Google Scholar 

  31. Maguire AM, Russell S, Chung DC, Yu ZF, Tillman A, Drack AV, et al. Durability of voretigene neparvovec for biallelic RPE65-mediated inherited retinal disease: phase 3 results at 3 and 4 years. Ophthalmology. 2021;128:1460–8.

    Article  PubMed  Google Scholar 

  32. Foong AW, Saw SM, Loo JL, Shen S, Loon SC, Rosman M, et al. Rationale and methodology for a population-based study of eye diseases in Malay people: The Singapore Malay eye study (SiMES). Ophthalmic Epidemiol. 2007;14:25–35.

    Article  PubMed  Google Scholar 

  33. Lavanya R, Jeganathan VS, Zheng Y, Raju P, Cheung N, Tai ES, et al. Methodology of the Singapore Indian Chinese Cohort (SICC) eye study: quantifying ethnic variations in the epidemiology of eye diseases in Asians. Ophthalmic Epidemiol. 2009;16:325–36.

    Article  PubMed  Google Scholar 

  34. Singapore Department of Statistics. Population trends. Singapore: Singapore Department of Statistics; 2021. p.50.

  35. Mann HB, Whitney DR. On a test of whether one of two random variables is stochastically larger than the other. Ann Math Stat. 1947;18:50–60.

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Funding

Funding

This work was supported by grant SHF-SNEC/0920/4 from the SingHealth Foundation.

Author information

Authors and Affiliations

  1. Health Services & Systems Research Program, Duke-NUS Graduate Medical School, Singapore, Singapore

    Junxing Chay

  2. Singapore Eye Research Institute, Singapore, Singapore

    Rachael Wei Chao Tang, Tien-En Tan, Choi Mun Chan, Ranjana Mathur, Hiok Hong Chan, Shaun S. K. P. Sim, Saadia Farooqui, Kelvin Y. C. Teo, Eva K. Fenwick, Ecosse L. Lamoureux, Chui Ming Gemmy Cheung & Beau J. Fenner

  3. Department of Medical Retina, Singapore National Eye Centre, Singapore, Singapore

    Tien-En Tan, Choi Mun Chan, Ranjana Mathur, Brian J. H. Lee, Hiok Hong Chan, Shaun S. K. P. Sim, Kelvin Y. C. Teo, Chui Ming Gemmy Cheung & Beau J. Fenner

  4. Duke-NUS Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Graduate Medical School, Singapore, Singapore

    Tien-En Tan, Choi Mun Chan, Ranjana Mathur, Hiok Hong Chan, Shaun S. K. P. Sim, Saadia Farooqui, Kelvin Y. C. Teo, Eva K. Fenwick, Ecosse L. Lamoureux, Chui Ming Gemmy Cheung & Beau J. Fenner

  5. Department of Paediatric Ophthalmology, Singapore National Eye Centre, Singapore, Singapore

    Saadia Farooqui

  6. Department of Ophthalmology and Visual Sciences, University of Iowa Hospitals and Clinics, Iowa City, IA, USA

    Beau J. Fenner

  7. Institute of Vision Research, University of Iowa, Iowa City, IA, USA

    Beau J. Fenner

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  1. Junxing Chay
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Contributions

JC, TET, EKF, ELL, CMGC, and BJF were responsible for the study design. RWCT, TET, CMC, RM, HHC, SSKPS, SF, KT, CMGC, and BJF were responsible for patient enrollment and data collection. JC, RWCT, BJHL, and BJF were responsible for data analysis. The manuscript was drafted by JC and BJF, and all authors contributed to critical revision of the manuscript.

Corresponding author

Correspondence to Beau J. Fenner.

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Chay, J., Tang, R.W.C., Tan, TE. et al. The economic burden of inherited retinal disease in Singapore: a prevalence-based cost-of-illness study. Eye 37, 3827–3833 (2023). https://doi.org/10.1038/s41433-023-02624-7

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  • DOI: https://doi.org/10.1038/s41433-023-02624-7

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