Prevalence, Incidence and Ecological Determinants of Diabetic Retinopathy in Iran: Systematic Review and Meta-analysis


Purpose: To estimate the pooled prevalence and incidence of diabetic retinopathy (DR) in Iran and to investigate their correlations with the Human Development Index (HDI), healthcare access (i.e., density of specialists and sub-specialists), and methodological issues.

Methods: Electronic databases such as PubMed, Embase, Scopus, Web of Science, Google Scholar, and local databases were searched for cohort and cross-sectional studies published prior to January 2018. Prevalence and incidence rates of DR were extracted from January 2000 to December 2017 and random effects models were used to estimate pooled effect sizes. The Joanna Briggs Institute critical appraisal tool was applied for quality assessment of eligible studies.

Results: A total of 55,445 participants across 33 studies were included. The pooled prevalence (95% CI) of DR in diabetic clinics (22 studies), eye clinics (4 studies), and general population (7 studies) was 31.8% (24.5 to 39.2), 57.8% (50.2 to 65.3), and 29.6% (22.6 to 36.5), respectively. It was 7.4% (3.9 to 10.8) for proliferative DR and 7.1% (4.9 to 9.4) for clinically significant macular edema. The heterogeneity of individual estimates of prevalence was highly significant. HDI (P < 0.001), density of specialists (P = 0.004), subspecialists (P < 0.001), and sampling site (P = 0.041) were associated with heterogeneity after the adjustment for type of DR, duration of diabetes, study year, and proportion of diabetics with controlled HbA1C.

Conclusion: Human development and healthcare access were correlated with the prevalence of DR. Data were scarce on the prevalence of DR in less developed provinces. Participant recruitment in eye clinics might overestimate the prevalence of DR.


Access to Health Care; Diabetic Retinopathy; Epidemiology; Human Development; Iran

1. Buch H, Vinding T, La Cour M, Appleyard M, Jensen GB, Nielsen NV. Prevalence and causes of visual impairment and blindness among 9980 Scandinavian adults: the Copenhagen City Eye Study. Ophthalmology 2004;111:53-61.

2. Brazionis L, Jenkins A, Keech A, Ryan C, Brown A, Boffa J, et al. Diabetic retinopathy in a remote Indigenous primary healthcare population: a Central Australian diabetic retinopathy screening study in the Telehealth Eye and Associated Medical Services Network project. Diabet Med 2018;35:630-639.

3. Tan GS, Gan A, Sabanayagam C, Tham YC, Neelam K, Mitchell P, et al. Ethnic differences in the prevalence
and risk factors of diabetic retinopathy: the Singapore epidemiology of eye diseases study. Ophthalmology

4. Cheung N, Mitchell P, Wong TY. Diabetic retinopathy. Lancet 2010. 10;376:124-136.

5. Flaxman SR, Bourne RR, Resnikoff S, Ackland P, Braithwaite T, Cicinelli MV, et al. Global causes of blindness
and distance vision impairment 1990-2020: a systematic review and meta-analysis. The Lancet Glob Health

6. Solomon SD, Chew E, Duh EJ, Sobrin L, Sun JK, VanderBeek BL, et al. Diabetic retinopathy: a position statement
by the American Diabetes Association. Diabetes Care 2017;40:412-418.

7. Ding J, Wong TY. Current epidemiology of diabetic retinopathy and diabetic macular edema. Curr Diab Rep

8. Ting DSW, Cheung GCM, Wong TY. Diabetic retinopathy: global prevalence, major risk factors, screening practices and public health challenges: a review. Clin Exp Ophthalmol 2016;44:260-277.

9. Caglar C, Demir E, Kucukler FK, Durmus M. A bibliometric analysis of academic publication on diabetic retinopathy disease trends during 1980-2014: a global and medical view. Int J Ophthalmol 2016;9:1663.

10. Publications UN, Programme UND. Human Development Report 2016: Human Development for Everyone: United Nations Publications; 2017.

11. Esteghamati A, Larijani B, Aghajani MH, Ghaemi F, Kermanchi J, Shahrami A, et al. Diabetes in Iran: prospective analysis from first nationwide diabetes report of National Program for Prevention and Control of Diabetes (NPPCD2016). Sci Rep 2017;7:13461.

12. Safaeipour M, Maveddat E. Assessment of areas with an emphasis on social indicators-economic and human
development indicators in combination with the use of GIS techniques and TOPSIS. Studies on Urban Planning
2013;1:11-27 [In Persian].

13. Hatef E, Fotouhi A, Hashemi H, Mohammad K, Jalali KH. Prevalence of retinal diseases and their pattern in Tehran: the Tehran eye study. Retina 2008;28:755-762.

14. Amini M, Aminorroaya A, Safaei H, Behrooz Z, Teimori A. Prevalence of diabetic retinopathy in newly diagnosed type 2 diabetic patients in Isfahan, Iran. Acta Endocrinologica 2008;4:415-423.

15. Stroup DF, Berlin JA, Morton SC, Olkin I, Williamson GD, Rennie D, et al. Meta-analysis of observational
studies in epidemiology: a proposal for reporting. JAMA 2000;283:2008-2012.

16. Salz DA, Witkin AJ. Imaging in diabetic retinopathy. Middle East Afr J Ophthalmol 2015;22:145.

17. Joanna Briggs Institute. Critical appraisal tools. Australia: The University of Adelaide; 2018 [cited 2018 Jun 01].
Available from:

18. Haghdoost A, Hashemi H, Haji Aghajani M, Janbabaee G, Maher A, Noori Hekmat S, et al. Specialized and
geographic distribution of specialists in Iran in 2016 and its estimates in 2026. Iran J Epidemiol 2018;13:122-132.

19. Brown LD, Cai TT, DasGupta A. Interval estimation for a binomial proportion. Stat Sci 2001;16:101-133.

20. Huedo-Medina TB, Sánchez-Meca J, Marín-Martínez F, Botella J. Assessing heterogeneity in meta-analysis: Q
statistic or I index? Psychol Methods 2006;11:193.

21. Janghorbani M, Amini M, Ghanbari H, Safaiee H. Incidence of and risk factors for diabetic retinopathy in Isfahan, Iran. Ophthalmic Epidemiol 2003;10:81-95.

22. Manaviat MR, Afkhami M, Shoja MR. Retinopathy and microalbuminuria in type II diabetic patients. BMC Ophthalmol 2004;4:9.

23. Abdollahi A, Daneshpazhooh M, Amirchaghmaghi E, Sheikhi S, Eshrati B, Bastanhagh M-H. Dermopathy and
retinopathy in diabetes: is there an association? Dermatology 2007;214:133-136.

24. Abdollahi A, Malekmadani M, Mansoori M, Bostak A, Mirshahi MAA. Prevalence of diabetic retinopathy in patients with newly diagnosed type II diabetes mellitus. Acta Med Iran 2006;44:415-419.

25. Amini M, Safaei H, Aminorroaya A. The incidence of microalbuminuria and its associated risk factors in type
2 diabetic patients in Isfahan, Iran. Rev Diabet Stud 2007;4:242.

26. Manaviat M, Rashidi M, Afkhami-Ardekani M. Four years incidence of diabetic retinopathy and effective factors on its progression in type II diabetes. Eur J Ophthalmol 2008;18:572-577.

27. Gharaagaji R, Fagihzadeh S, Meshkani M, Rohipor R. The prevalence of diabetic retinopathy and related risk factors in diabetic type I, in Tehran, Iran. Res J Bio Sci 2008;3:596- 600.

28. Golbahar J, Rahimi M, Tabei MB, Aminzadeh MA. Clinical risk factors and association of hyperhomocysteinemia with diabetic retinopathy in Iranian type 2 diabetes patients: a cross-sectional study from Shiraz, Southern Iran. Diabetes Metab Syndr 2008;2:192-201.
29. Hosseini SM, Maracy MR, Amini M, Baradaran HR. A risk score development for diabetic retinopathy screening in Isfahan-Iran. J Res Med Sci 2009;14:105.

30. Javadi MA, Katibeh M, Rafati N, Dehghan MH, Zayeri F, Yaseri M, et al. Prevalence of diabetic retinopathy in
Tehran province: a population-based study. BMC Ophthalmol 2009;9:12.

31. Soleymani A, Moazzezi Z, Gorjizadeh A. Frequency of Ophthalmic complications on 140 cases of Type II diabetes mellitus, Babol-Iran. World App Sci J 2012;18:550-553.

32. Javanbakht M, Abolhasani F, Mashayekhi A, Baradaran HR. Health related quality of life in patients with type 2
diabetes mellitus in Iran: a national survey. PLOS ONE 2012;7:e44526.

33. Najafi L, Malek M, Valojerdi AE, Aghili R, Khamseh ME, Fallah AE, et al. Dry eye and its correlation to diabetes
microvascular complications in people with type 2 diabetes mellitus. J Diabetes Complicat 2013;27:459-462.

34. Shaghaghi A, Ahmadi A, Matlabi H. Iranian patients require more pertinent care to prevent type 2 diabetes
complications. Adv Prev Med 2014;2014:409391.

35. Gholamhossein Y, Behrouz H, Asghar Z. Diabetic retinopathy risk factors: plasma erythropoietin as a risk factor for proliferative diabetic retinopathy. Korean J Ophthalmol 2014;28:373-378.

36. Hosseini MS, Rostami Z, Saadat A, Saadatmand SM, Naeimi E. Anemia and microvascular complications in
patients with type 2 diabetes mellitus. Nephrourol Mon 2014;6:e19976.

37. Maghbooli Z, Pasalar P, Keshtkar A, Farzadfar F, Larijani B. Predictive factors of diabetic complications: a possible link between family history of diabetes and diabetic retinopathy. J Diabetes Metab Disord 2014;13:55.

38. Tazhibi M, Sarrafzade S, Amini M. Retinopathy risk factors in type II diabetic patients using factor analysis and
discriminant analysis. J Educ Health Promot 2014;3:85.

39. Ghodsi R, HamayeliMeharbani H, Avand A-Q, Bordbar A, Ahmadzadeh S. A study on the prevalence of diabetic
complications in Fasa diabetes clinic. Asian J Med Pharm Res 2014;4:68-72.

40. Dehghan MH, Katibeh M, Ahmadieh H, Nourinia R, Yaseri M. Prevalence and risk factors for diabetic retinopathy in the 40 to 80 year-old population in Yazd, Iran: The Yazd Eye Study. J Diabetes 2015;7:139-141.

41. Azizi-Soleiman F, Heidari-Beni M, Ambler G, Omar R, Amini M, Hosseini S-M. Iranian risk model as a predictive tool for retinopathy in patients with type 2 diabetes. Can J Diabetes 2015;39:358-363.

42. Shamshirgaran SM, Ataei J, Alamdari MI, Safaeian A, Aminisani N. Predictors of health-related quality of life
among people with type II diabetes Mellitus in Ardabil, Northwest of Iran, 2014. Prim Care Diabetes 2016;10:244-

43. Rasoulinejad SA, Hajian-Tilaki K, Mehdipour E. Associated factors of diabetic retinopathy in patients that referred to teaching hospitals in Babol. Caspian J Intern Med 2015;6:224.

44. Mehravar F, Mansournia MA, Holakouie-Naieni K, NasliEsfahani E, Mansournia N, Almasi-Hashiani A. Associations between diabetes self-management and microvascular complications in patients with type 2 diabetes. Epidemiol Health 2016;38:e2016004.
45. Valizadeh R, Moosazadeh M, Bahaadini K, Vali L, Lashkari T, Amiresmaili M. Determining the prevalence of retinopathy and its related factors among patients with type 2 Diabetes in Kerman, Iran. Osong Public Health Res
Perspect 2016;7:296-300.

46. Aidenloo NS, Mehdizadeh A, Valizadeh N, Abbaszadeh M, Qarequran S, Khalkhali H. Optimal glycemic and
hemoglobin a1c thresholds for diagnosing diabetes based on prevalence of retinopathy in an iranian population. Iran Red Crescent Med J 2016;18:31254.

47. Hashemi H, Khabazkhoob M, Nabovati P, Ostadimoghaddam H, Shafaee S, Doostdar A, et al. The prevalence
of age-related eye disease in an elderly population. Ophthalmic Epidemiol 2017;24:222-228. 48. Dehghan H, Charkazi A, Kouchaki GM, Zadeh BP,

48. Dehghan BA, Matlabi M, et al. General self-efficacy and diabetes management self-efficacy of diabetic patients referred to diabetes clinic of Aq Qala, North of Iran. J Diabetes Metab Disord 2017;16:8.

49. Shamshirgaran S, Mamaghanian A, Aliasgarzadeh A, Aiminisani N, Iranparvar-Alamdari M, Ataie J. Age differences in diabetes-related complications and glycemic control. BMC Endocr Disord 2017;17:25.

50. Katibeh M, Behboudi H, Moradian S, Alizadeh Y, Beiranvand R, Sabbaghi H, et al. Rapid assessment of avoidable blindness and diabetic retinopathy in Gilan province, Iran. Ophthalmic epidemiol 2017;24:381-387.

51. Williams R, Airey M, Baxter H, Forrester J, KennedyMartin T, Girach A. Epidemiology of diabetic retinopathy
and macular oedema: a systematic review. Eye (Lond) 2004;18:963.

52. Sivaprasad S, Gupta B, Crosby-Nwaobi R, Evans J. Prevalence of diabetic retinopathy in various ethnic groups:
a worldwide perspective. Surv Ophthalmol 2012;57:347- 370.

53. French DD, Behrens JJ, Jackson KL, Kho AN, Walunas TL, Evans CT, et al. Payment reform needed to address health disparities of undiagnosed diabetic retinopathy in the city of Chicago. Ophthalmol Ther 2017;6:123-131.

54. Gibson DM. Eye care availability and access among individuals with diabetes, diabetic retinopathy, or age-related macular degeneration. JAMA Ophthalmol 2014;132:471- 477.

55. MacLennan PA, McGwin G, Heckemeyer C, Lolley VR, Hullett S, Saaddine J, et al. Eye care use among a highrisk diabetic population seen in a public hospital’s clinics. JAMA Ophthalmol 2014;132:162-167.

56. Tajunisah I, Wong P, Tan L, Rokiah P, Reddy S. Awareness of eye complications and prevalence of retinopathy in the first visit to eye clinic among type 2 diabetic patients. Int J Ophthalmol 2011;4:519.

57. Gibson DM. The local availability of eye care providers and the vision health of adults in the United States. Ophthalmic Epidemiol 2016;23:223-231.

58. Thapa R, Twyana SN, Paudyal G, Khanal S, van Nispen R, Tan S, et al. Prevalence and risk factors of diabetic
retinopathy among an elderly population with diabetes in Nepal: the Bhaktapur Retina Study. Clin Ophthalmol

59. Pradeepa R, Anitha B, Mohan V, Ganesan A, Rema M. Risk factors for diabetic retinopathy in a South Indian type 2 diabetic population-the Chennai Urban Rural Epidemiology Study (CURES) Eye Study 4. Diabet Med 2008;25:536- 542.

60. Mumtaz SN, Fahim MF, Arslan M, Shaikh SA, Kazi U, Memon MS. Prevalence of diabetic retinopathy in Pakistan: a systematic review. Pak J Med Sci 2018;34:493.

61. Kanjee R, Dookeran RI, Mathen MK, Stockl FA, Leicht R. Six-year prevalence and incidence of diabetic retinopathy and cost-effectiveness of tele-ophthalmology in Manitoba. Can J Ophthalmol 2016;51:467-470.

62. Vila L, Viguera J, Aleman R. Diabetic retinopathy and blindness in Spain: epidemiology and prevention. Endocrinol Nutr 2008;55:459-475.

63. Bourne RR, Stevens GA, White RA, Smith JL, Flaxman SR, Price H, et al. Causes of vision loss worldwide, 1990-2010: a systematic analysis. Lancet Glob Health 2013;1:e339- e349.

64. Zheng Y, He M, Congdon N. The worldwide epidemic of diabetic retinopathy. Indian J Ophthalmol 2012;60:428.

65. Romero-Aroca P, Navarro-Gil R, Valls-Mateu A, SagarraAlamo R, Moreno-Ribas A, Soler N. Differences in incidence of diabetic retinopathy between type 1 and 2 diabetes mellitus: a nine-year follow-up study. Br J Ophthalmol 2017;101:1346-1351.

66. Romero-Aroca P, Fernàndez-Alart J, Baget-Bernaldiz M,
Méndez-Marín I, Salvat-Serra M. Diabetic retinopathy epidemiology in type II diabetic patients. Effect of the changes in the diagnostic criteria and stricter control of the diabetes between 1993 and 2005 on the incidence of diabetic retinopathy. Arch Soc Esp Oftalmol 2007;82:209-218.

67. Raman R, Ganesan S, Pal SS, Gella L, Kulothungan V, Sharma T. Incidence and progression of diabetic retinopathy in urban India: Sankara Nethralaya-Diabetic Retinopathy Epidemiology and Molecular Genetics Study (SNDREAMS II), Report 1. Ophthalmic Epidemiol 2017;24:294- 302.

68. Song SJ, Han K, Choi KS, Ko SH, Rhee Ej, Park CY, et al. Trends in diabetic retinopathy and related medical
practices among type 2 diabetes patients: results from the National Insurance Service Survey 2006-2013. J Diabetes Investig 2018;9:173-178.

69. Bek T, Lund-Andersen H, Hansen AB, Johnsen KB, Sandbæk A, Lauritzen T. The prevalence of diabetic
retinopathy in patients with screen-detected type 2 diabetes in Denmark: the ADDITION study. Acta Ophthalmol

70. Ruta L, Magliano D, Lemesurier R, Taylor H, Zimmet P, Shaw J. Prevalence of diabetic retinopathy in type 2
diabetes in developing and developed countries. Diabet Med 2013;30:387-398.

71. Sikorski BL, Malukiewicz G, Stafiej J, Lesiewska-Junk H, Raczynska D. The diagnostic function of OCT in diabetic
maculopathy. Mediators Inflamm 2013;2013;434560.