Association between dietary niacin intake and diabetic retinopathy in a Catalonian population: a cross-sectional study

Jeimy Katherine Torres-Méndez^1,2Marina Idalia Rojo-López^1,3Maria Antentas¹Pau Vendrell³Emilio Ortega⁴Nuria Alonso^5,6Esmeralda Castelblanco⁷Andrea Muscarà⁸Esther Rubinat⁹Nuria Alcubierre^10,11Marta Hernández^11,12Joana Rossell^1,5Minerva Granado^5,9Didac Mauricio^1*Josep Julve^1,5*

• ¹Institut de Recerca de l'Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
• ²Department of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain
• ³Fundació Institut Universitari per a la Recerca a l'Atenció Primària de Salut Jordi Gol i Gurina, Barcelona, Spain
• ⁴Institut d'Investigacions Biomèdiques August Pi i Suñer, Hospital Clínic, Barcelona, Spain
• ⁵Center for Biomedical Research on Diabetes and Associated Metabolic Diseases (CIBERDEM), Madrid, Spain
• ⁶Hospital Germans Trias i Pujol, Badalona, Spain
• ⁷Washington University School of Medicine, Saint Louis, United States
• ⁸University of Messina, Messina, Italy
• ⁹University of Lleida, Lleida, Spain
• ¹⁰Avantmedic Center, Lleida, Spain
• ¹¹University Hospital Arnau de Vilanova, Lleida, Spain
• ¹²Lleida Institute for Biomedical Research Dr. Pifarré Foundation, IRBLleida, Lleida, Spain

Background: Accumulating evidence suggests that niacin interventions may have a beneficial role in preventing ophthalmological microangiopathic remodeling. This study aimed to assess the impact of niacin intake on the presence of diabetic retinopathy (DR) in two independent Mediterranean cohorts of individuals with type 1 diabetes (T1D) and type 2 diabetes (T2D). Methods: Cross-sectional, population-based epidemiologic study. A total of 243 individuals with T1D, and 291 individuals with T2D. All participants underwent an eye examination. Dietary niacin intake was analyzed using a validated Spanish 101-items food frequency questionnaire consumption. The association between niacin intake and DR was assessed using a multivariate logistic regression, with potential non-linear associations further explored through restricted cubic spline regression. DR diagnostic was established via multifield stereoscopic retinal photography, in accordance with the international consensus on DR. Results: DR was identified in 103 out of 243 individuals with T1D and 144 out of 291 with T2D. Dietary niacin intake did not differ within the study groups according to DR status. Multivariate logistic regression models also revealed no association between dietary niacin intake and DR. As previously described, the duration of diabetes for T1D and T2D, (OR (95%CI), 1.02 (1.01-1.03) and 1.02 (1.02-1.03), respectively) and glycated hemoglobin (HbA1c) (OR (95%CI), 1.16 (1.09-1.24) and 1.14 (1.09-1.18), respectively) were identified as the main determinant variables for DR in both groups. Conclusions: We found that dietary niacin intake was not associated with the presence of RD in subjects with either T1D or T2D. Further research is needed to better understand the potential role of niacin in the development or prevention of DR.