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The Chinese keratoconus (CKC) cohort study

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Abstract

The Chinese keratoconus (CKC) cohort study is a population-based longitudinal prospective cohort study in the Chinese population involving a clinical database and biobanks. This ongoing study focuses on the prevention of KC progression and is the first to involve the effect of gene‒environment interactions on KC progression. The CKC cohort is hospital-based and dynamic and was established in Zhengzhou, China; KC patients (n = 1114) from a large geographical area were enrolled from January 2019 to June 2023, with a mean age of 22.23 years (6‒57 years). Demographic details, socioeconomic characteristics, lifestyle, disease history, surgical history, family history, and visual and social function data are being collected using questionnaires. General physical examination, eye examination, biological specimen collection, and first-degree relative data were collected and analyzed in the present study. The primary focus of the present study was placed on gene, environment and the effect of gene‒environment interactions on KC progression. The follow-up of the CKC cohort study is expected to include data collection at 3 months, 6 months, and 1 year after the initial examination and then at the annual follow-up examinations. The first follow-up of the CKC cohort study was recorded. A total of 918 patients completed the follow-up by June 1, 2023, with a response rate of 82.40%. Aside from the younger age of patients who were followed up, no significant differences were found between patients who were followed up and patients who were not.

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References

  1. Mas Tur V, MacGregor C, Jayaswal R, O’Brart D, Maycock N. A review of keratoconus: diagnosis, pathophysiology, and genetics. Surv Ophthalmol. 2017;62:770–83.

    Article  PubMed  Google Scholar 

  2. Rabinowitz YS. Keratoconus Surv Ophthalmol. 1998;42:297–319.

    Article  CAS  PubMed  Google Scholar 

  3. Matthaei M, Sandhaeger H, Hermel M, et al. Changing indications in penetrating Keratoplasty: a systematic review of 34 years of global reporting. Transplantation. 2017;101:1387–99.

    Article  PubMed  Google Scholar 

  4. Santodomingo-Rubido J, Carracedo G, Suzaki A, Villa-Collar C, Vincent SJ, Wolffsohn JS. Keratoconus: an updated review. Contact lens Anterior eye: J Br Contact Lens Association 2022:101559.

  5. Gomes JA, Tan D, Rapuano CJ, et al. Global consensus on keratoconus and ectatic diseases. Cornea. 2015;34:359–69.

    Article  PubMed  Google Scholar 

  6. Pan CW, Cheng CY, Sabanayagam C, et al. Ethnic variation in central corneal refractive power and steep cornea in asians. Ophthalmic Epidemiol. 2014;21:99–105.

    Article  PubMed  Google Scholar 

  7. Hashemi H, Heydarian S, Hooshmand E, et al. The prevalence and risk factors for Keratoconus: a systematic review and Meta-analysis. Cornea. 2020;39:263–70.

    Article  PubMed  Google Scholar 

  8. Xu L, Wang YX, Guo Y, You QS, Jonas JB. Prevalence and associations of steep cornea/keratoconus in Greater Beijing. The Beijing Eye Study. PLoS ONE. 2012;7:e39313.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  9. Rebenitsch RL, Kymes SM, Walline JJ, Gordon MO. The lifetime economic burden of keratoconus: a decision analysis using a markov model. Am J Ophthalmol. 2011;151:768–e7732.

    Article  PubMed  PubMed Central  Google Scholar 

  10. Lass JH, Lembach RG, Park SB, et al. Clinical management of keratoconus. A multicenter analysis. Ophthalmology. 1990;97:433–45.

    Article  CAS  PubMed  Google Scholar 

  11. Sandvik GF, Thorsrud A, Raen M, Ostern AE, Saethre M, Drolsum L. Does corneal collagen cross-linking reduce the need for keratoplasties in patients with. Keratoconus? Cornea. 2015;34:991–5.

    Article  PubMed  Google Scholar 

  12. Gordon MO, Steger-May K, Szczotka-Flynn L, et al. Baseline factors predictive of incident penetrating keratoplasty in keratoconus. Am J Ophthalmol. 2006;142:923–30.

    Article  PubMed  Google Scholar 

  13. Yang K, Xu L, Fan Q, et al. A hospital-based study on clinical data, demographic data and visual function of keratoconus patients in Central China. Sci Rep. 2021;11:7559.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  14. Hong J, Shi W, Liu Z, et al. Limitations of Keratoplasty in China: a Survey Analysis. PLoS ONE. 2015;10:e0132268.

    Article  PubMed  PubMed Central  Google Scholar 

  15. Jhanji V, Sharma N, Vajpayee RB. Management of keratoconus: current scenario. Br J Ophthalmol. 2011;95:1044–50.

    Article  PubMed  Google Scholar 

  16. Yang K, Xu L, Zhu M, et al. A bibliometric analysis of the top 100 most-cited articles on keratoconus. Int Ophthalmol. 2022;42:3357–66.

    Article  PubMed  Google Scholar 

  17. Efron N, Morgan PB, Jones LW, Nichols JJ. Bibliometric analysis of the keratoconus literature. Clin Experimental Optometry. 2022;105:372–7.

    Article  Google Scholar 

  18. Gao H, Huang T, Pan Z, et al. Survey report on keratoplasty in China: a 5-year review from 2014 to 2018. PLoS ONE. 2020;15:e0239939.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  19. Zadnik K, Barr JT, Gordon MO, Edrington TB. Biomicroscopic signs and disease severity in keratoconus. Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study Group. Cornea. 1996;15:139–46.

    Article  CAS  PubMed  Google Scholar 

  20. McGhee CN. 2008 Sir Norman McAlister Gregg Lecture: 150 years of practical observations on the conical cornea–what have we learned? Clinical & experimental ophthalmology 2009;37:160 – 76.

  21. Benito-Pascual B, Kandel H, Abbondanza M, Mills R, Sullivan L, Watson SL. Efficacy and safety of standard corneal cross-linking procedures performed with short Versus Standard Riboflavin induction: a Save Sight Keratoconus Registry Study. Cornea. 2023;42:326–31.

    Article  PubMed  Google Scholar 

  22. Kandel H, Nguyen V, Piermarocchi S, et al. Quality of life impact of eye diseases: a Save Sight registries study. Clin Exp Ophthalmol. 2022;50:386–97.

    Article  PubMed  PubMed Central  Google Scholar 

  23. Jiménez-García M, Koppen SND, Varssano C, Rozema D. Baseline findings in the Retrospective Digital Computer Analysis of Keratoconus Evolution (REDCAKE) Project. Cornea. 2021;40:156–67.

    Article  PubMed  Google Scholar 

  24. Gokul A, Ziaei M, Mathan JJ, et al. The Aotearoa Research Into Keratoconus Study: Geographic distribution, demographics, and clinical characteristics of Keratoconus in New Zealand. Cornea. 2022;41:16–22.

    Article  PubMed  Google Scholar 

  25. Hunter DJ. Gene-environment interactions in human diseases. Nat Rev Genet. 2005;6:287–98.

    Article  CAS  PubMed  Google Scholar 

  26. Manolio TA, Bailey-Wilson JE, Collins FS. Genes, environment and the value of prospective cohort studies. Nat Rev Genet. 2006;7:812–20.

    Article  CAS  PubMed  Google Scholar 

  27. Yang K, Gu Y, Xu L, et al. Distribution of pediatric keratoconus by different age and gender groups. Front Pead. 2022;10:937246.

    Article  Google Scholar 

  28. Maile HP, Li JO, Fortune MD, et al. Personalized model to predict keratoconus progression from demographic, topographic and genetic data. Am J Ophthalmol. 2022;240:321–9.

    Article  PubMed  Google Scholar 

  29. Zadnik K, Barr JT, Edrington TB, et al. Baseline findings in the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study. Investig Ophthalmol Vis Sci. 1998;39:2537–46.

    CAS  Google Scholar 

  30. Hwang S, Lim DH, Chung TY. Prevalence and incidence of Keratoconus in South Korea: a Nationwide Population-based study. Am J Ophthalmol. 2018;192:56–64.

    Article  PubMed  Google Scholar 

  31. Wang Y, Xu L, Wang S, et al. A hospital-based study on the prevalence of Keratoconus in First-Degree relatives of patients with Keratoconus in Central China. J Ophthalmol. 2022;2022:6609531.

    Article  PubMed  PubMed Central  Google Scholar 

  32. Xu L, Yang K, Zhu M, et al. Trio-based exome sequencing broaden the genetic spectrum in keratoconus. Exp Eye Res. 2023;226:109342.

    Article  CAS  PubMed  Google Scholar 

  33. Xu L, Yang K, Fan Q, et al. Exome sequencing identification of susceptibility genes in Chinese patients with keratoconus. Ophthalmic Genet. 2020;41:518–25.

    Article  CAS  PubMed  Google Scholar 

  34. Xu L, Yang K, Yin S, et al. Family-based exome sequencing identifies candidate genes related to keratoconus in Chinese families. Front Genet. 2022;13:988620.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  35. Xu L, Yang K, Fan Q, Zhao D, Pang C, Ren S. Whole mitochondrial genome analysis in Chinese patients with keratoconus. Mol Vis. 2021;27:270–82.

    CAS  PubMed  PubMed Central  Google Scholar 

  36. Ren S, Yang K, Fan Q, et al. Bioinformatics analysis of key candidate genes and pathways in Chinese patients with keratoconus. Exp Eye Res. 2023;231:109488.

    Article  CAS  PubMed  Google Scholar 

  37. Yang K, Li D, Xu L, Pang C, Zhao D, Ren S. Independent and interactive effects of eye rubbing and atopy on keratoconus. Front Immunol. 2022;13:999435.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  38. Ren S, Tu R, Xu L et al. A high body mass index strengthens the association between the time of eye rubbing and keratoconus in a Chinese population: a case control study. BMC Public Health 2023;23:2032.

  39. He W, Han X, Ong JS, et al. Association of novel loci with Keratoconus susceptibility in a Multitrait Genome-Wide Association Study of the UK Biobank Database and Canadian Longitudinal Study on Aging. JAMA Ophthalmol. 2022;140:568–76.

    Article  PubMed  PubMed Central  Google Scholar 

  40. Yang K, Xu L, Fan Q, et al. Evaluation of new Corvis ST parameters in normal, Post-LASIK, Post-LASIK keratectasia and keratoconus eyes. Sci Rep. 2020;10:5676.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  41. Ren S, Xu L, Fan Q, Gu Y, Yang K. Accuracy of new Corvis ST parameters for detecting subclinical and clinical keratoconus eyes in a Chinese population. Sci Rep. 2021;11:4962.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  42. Yang K, Fan Q, Xu L, Gu Y, Pang C, Ren S. Accuracy of tomographic and biomechanical parameters in detecting unilateral post-LASIK keratoectasia and fellow eyes. Front Bioeng Biotechnol. 2023;11:1181117.

    Article  PubMed  PubMed Central  Google Scholar 

  43. Yang K, Xu L, Fan Q, Ren S. Association between corneal stiffness parameter at the First Applanation and Keratoconus Severity. J Ophthalmol. 2020;2020:6667507.

    Article  PubMed  PubMed Central  Google Scholar 

  44. Yang K, Xu L, Fan Q, Zhao D, Ren S. Repeatability and comparison of new Corvis ST parameters in normal and keratoconus eyes. Sci Rep. 2019;9:15379.

    Article  PubMed  PubMed Central  Google Scholar 

  45. Tan JCK, Nguyen V, Fenwick E, Ferdi A, Dinh A, Watson SL. Vision-Related Quality of Life in Keratoconus: a Save Sight Keratoconus Registry Study. Cornea. 2019;38:600–4.

    Article  PubMed  Google Scholar 

  46. Weed KH, MacEwen CJ, Giles T, Low J, McGhee CN. The Dundee University Scottish Keratoconus study: demographics, corneal signs, associated diseases, and eye rubbing. Eye. 2008;22:534–41.

    Article  CAS  PubMed  Google Scholar 

Download references

Acknowledgements

All relevant data are included in the paper and its Supporting Information files. Contact Dr. Shengwei Ren (shengweiren1984@163.com and ysgzz2018@163.com) for additional information. The authors would like to thank all the participants of this study.

Funding

This research was supported by the General project of Natural Science Foundation of Henan Province (No. 222300420536), Henan Provincial Medical Science Building Key Program (No. SBGJ202002028, SBGJ202102051, SBGJ202303043), Henan Provincial Medical Science and Technology Joint Program (No. LHGJ20210080), Henan Young Health Science and Technology Innovation Outstanding Program (No. YXKC2020023). The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

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Authors and Affiliations

  1. Henan Provincial People’s Hospital, Henan Eye Hospital, Henan Eye Institute, People’s Hospital of Zhengzhou University, Henan University People’s Hospital, 7 Weiwu Road, Zhengzhou, Henan, China

    Kaili Yang, Liyan Xu, Yuwei Gu, Qi Fan, Chenjiu Pang & Shengwei Ren

  2. Department of Epidemiology and Biostatistics, College of Public Health, Zhengzhou University, Zhengzhou, Henan, China

    Xiaotian Liu & Chongjian Wang

  3. Zhengzhou University People’s Hospital, Henan Provincial People’s Hospital, Henan Eye Hospital, Henan Eye Institute, Zhengzhou, Henan, China

    Shanshan Yin, Yifan Wang, Yi Yuan & Chenchen Yin

  4. Henan University People’s Hospital, Henan Provincial People’s Hospital, Henan Eye Hospital, Henan Eye Institute, Zhengzhou, Henan, China

    Anqi Chang

  5. Xinxiang Medical University, Henan Provincial People’s Hospital, Henan Eye Hospital, Henan Eye Institute, Zhengzhou, Henan, China

    Yonghao Zang

Authors
  1. Kaili Yang
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Contributions

Concept and design: Shengwei Ren. Acquisition, analysis, or interpretation of data: Shengwei Ren, Kaili Yang, Xiaotian Liu, Liyan Xu, Yuwei Gu, Qi Fan, Yonghao Zang, Chenchen Yin, Chenjiu Pang. Drafting of the manuscript: Shengwei Ren, Kaili Yang. Critical revision of the manuscript for important intellectual content: All authors. Statistical analysis: Kaili Yang, Liyan Xu, Shanshan Yin. Obtained funding: Shengwei Ren, Kaili Yang, Liyan Xu. Administrative, technical, or material support: Xiaotian Liu, Yi Yuan, Liyan Xu, Yifan Wang, Anqi Chang, Chenjiu Pang, Chongjian Wang. Supervision: Shengwei Ren, Kaili Yang.

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Correspondence to Shengwei Ren.

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Supplementary Material 1

: Supplemental Fig. 1. Geographic location of the CKC cohort study.

Supplementary Material 2

: Supplemental Fig. 2. KC severity and treatments in the CKC cohort study. (A) KC severity; (B) KC treatments.

Supplementary Material 3

: Supplemental Fig. 3. Violin plot showing the distributions of BMI, SBP, DBP, and HR. (A) BMI, body mass index; (B) HR, heart rate; (C) SBP, systolic blood pressure; (D) DBP, diastolic blood pressure.

Supplementary Material 4

: Supplemental Table 1. Pervious study related to the epidemiology of KC. Supplemental Table 2. The recruitment process and data collection of family members. Supplemental Table 3. Overview of published and accepted papers based on the CKC cohort data. Supplemental Table 4. Baseline data of corneal basic, corneal tomography and corneal biomechanical parameters in KC eyes.

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Yang, K., Liu, X., Xu, L. et al. The Chinese keratoconus (CKC) cohort study. Eur J Epidemiol (2024). https://doi.org/10.1007/s10654-024-01128-2

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