Serum Levels of Vitamin D in Diabetic Patients With and Without Retinopathy


Purpose: To evaluate the levels of vitamin D in the serum of diabetic patients with and without diabetic retinopathy (DR).

Methods: Thirty patients with DR and thirty diabetic patients without retinopathy were included in this cross-sectional study. Based on ophthalmic examination, patients with DR were categorized into having non-proliferative retinopathy (NPDR) and proliferative retinopathy (PDR). Patients were tested for fasting blood sugar (FBS), hemoglobin A1C (HbA1C), 25-hydroxy vitamin D (25 (OH) D), and creatinine levels in the serum, and for urine protein. Vitamin D deficiency was defined as a serum 25 (OH) D level < 20 ng/mL.

Results: We found that all diabetic patients had mild vitamin D deficiency (serum 25 (OH) D level = 10–20 ng/mL). The mean serum 25 (OH) D concentration in patients with DR was lower than in those without DR (12.10 ± 14.62 ng/mL vs 15.61 ± 9.40 ng/mL, respectively, P = 0.012). Trace or more proteinuria was frequently present in patients with DR than in those without DR (56% in DR vs 30% in non-DR; P = 0.037). There were no significant differences in the FBS, HbA1C, and serum creatinine levels between patients with or without retinopathy.

Conclusion: The present study demonstrated that patients with DR had lower levels of serum vitamin D compared with those without retinopathy.


Diabetes Mellitus, Diabetic Retinopathy, 25-Hydroxy Vitamin D

1. Geiss LS, Wang J, Cheng YJ, Thompson TJ, Barker L, Li Y, et al. Prevalence and incidence trends for diagnosed diabetes among adults aged 20 to 79 years, United States, 1980–2012. JAMA 2014;312:1218–1226.

2. NCD Risk Factor Collaboration (NCD-RisC). Worldwide trends in diabetes since 1980: a pooled analysis of 751 population-based studies with 4.4 million participants. Lancet 2016;387:1513–1530.

3. Wan TT, Li XF, Sun YM, Li YB, Su Y. Recent advances in understanding the biochemical and molecular mechanism of diabetic retinopathy. Biomed Pharmacother 2015;74:145–147.

4. Bayani MA, Akbari R, Banasaz B, Saeedi F. Status of vitamin-D in diabetic patients. Caspian J Intern Med 2014;5:40–42.

5. Cangoz S, Chang YY, Chempakaseril SJ, Guduru RC, Huynh LM, John JS, et al. Vitamin D and type 2 diabetes mellitus. J Clin Pharm Ther 2013;38:81–84.

6. Mathieu C, Gysemans C, Giulietti A, Bouillon R. Vitamin D and diabetes. Diabetologia 2005;48:1247–1257.

7. Wimalawansa SJ. Associations of vitamin D with insulin resistance, obesity, type 2 diabetes, and metabolic syndrome. J Steroid Biochem Mol Biol 2018;175:177–189.

8. Michaud SE, Renier G. Direct regulatory effect of fatty acids on macrophage lipoprotein lipase: potential role of PPARs. Diabetes 2001;50:660–666.

9. Albert DM, Scheef EA, Wang S, Mehraein F, Darjatmoko SR, Sorenson CM, et al. Calcitriol is a potent inhibitor of retinal neovascularization. Invest Ophthalmol Vis Sci 2007;48:2327–2334.

10. Zhang J, Upala S, Sanguankeo A. Relationship between vitamin D deficiency and diabetic retinopathy: a metaanalysis. Can J Ophthalmol 2017;52:219–224.

11. Langlois K, Greene-Finestone L, Little J, Hidiroglou N, Whiting S. Vitamin D status of Canadians as measured in the 2007 to 2009 Canadian Health Measures Survey. Health Rep 2010;21:47–55.

12. Forrest KY, Stuhldreher WL. Prevalence and correlates of vitamin D deficiency in US adults. Nutr Res 2011;31:48–54.

13. Larijani B, Hossein-Nezhad A, Feizabad E, Maghbooli Z, Adibi H, Ramezani M, et al. Vitamin D deficiency, bone turnover markers and causative factors among adolescents: a cross-sectional study. J Diabetes Metab Disord 2016;15:46.

14. Holick MF. Vitamin D deficiency. N Engl J Med 2007;357:266–281.

15. Rhee SY, Hwang YC, Chung HY, Woo JT. Vitamin D and diabetes in Koreans: analyses based on the Fourth Korea National Health and Nutrition Examination Survey (KNHANES), 2008–2009. Diabet Med 2012;29:1003–1010.

16. Bonakdaran S, Shoeibi N. Is there any correlation between vitamin D insufficiency and diabetic retinopathy? Int J Ophthalmol 2015;8:326–331.

17. Isaia G, Giorgino R, Adami S. High prevalence of hypovitaminosis D in female type 2 diabetic population. Diabetes Care 2001;24:1496.

18. Alam U, Amjad Y, Chan AW, Asghar O, Petropoulos IN, Malik RA. Vitamin D deficiency is not associated with diabetic retinopathy or maculopathy. J Diabetes Res 2016;2016:6156217.

19. Payne JF, Ray R, Watson DG, Delille C, Rimler E, Cleveland J, et al. Vitamin D insufficiency in diabetic retinopathy. Endocr Pract 2012;18:185–193.

20. Luo BA, Gao F, Qin LL. The association between vitamin D deficiency and diabetic retinopathy in type 2 diabetes: a meta-analysis of observational studies. Nutrients 2017;9:3.

21. Ben-Shoshan M, Amir S, Dang DT, Dang LH, Weisman Y, Mabjeesh NJ. 1alpha,25-dihydroxyvitamin D3 (Calcitriol) inhibits hypoxia-inducible factor-1/vascular endothelial growth factor pathway in human cancer cells. Mol Cancer Ther 2007;6:1433–1439.

22. Wu-Wong JR, Nakane M, Ma J, Ruan X, Kroeger PE. Effects of vitamin D analogs on gene expression profiling in human coronary artery smooth muscle cells. Atherosclerosis 2006;186:20–28.

23. Timms PM, Mannan N, Hitman GA, Noonan K, Mills PG, Syndercombe-Court D, et al. Circulating MMP9, vitamin D and variation in the TIMP-1 response with VDR genotype: mechanisms for inflammatory damage in chronic disorders? QJM 2002;95:787–796.

24. Pan CW, Wang S, Qian DJ, Xu C, Song E. Prevalence, awareness, and risk factors of diabetic retinopathy among adults with known type 2 diabetes mellitus in an urban community in China. Ophthalmic Epidemiol 2017;24:188– 194.

25. Bansal P, Gupta R, Kotecha M. Frequency of diabetic retinopathy in patients with diabetes mellitus and its correlation with duration of diabetes mellitus. Med J Dr DY Patil Univ 2013;6:366–369.

26. Jenchitr W, Samaiporn S, Lertmeemongkolchai P, Chongwiriyanurak T, Anujaree P, Chayaboon D, et al. Prevalence of diabetic retinopathy in relation to duration of diabetes mellitus in community hospitals of Lampang. J Med Assoc Thai 2004;87:1321–1326.

27. Vashi PG, Lammersfeld CA, Braun DP, Gupta D. Serum 25- hydroxyvitamin D is inversely associated with body mass index in cancer. Nutr J 2011;10:51.