Cheese consumption and risk of diabetic retinopathies: A Mendelian Randomization study

Objectives Diabetic retinopathy (DR) is the leading cause of visual loss in working-age adults worldwide. Cheese is a widely consumed dairy product, and cheese intake has various health benefiting effects. This study aimed to use Mendelian randomization (MR) to investigate the impact of cheese consumption on DR. Methods The genome-wide association study (GWAS) summary statistic generated from 451486 European descent was introduced to identify the valid instrumental variables (IVs) for cheese intake. As the outcomes, the GWAS data of three outcome traits (DR, proliferative diabetic retinopathy or PDR, diabetic maculopathy or DMP) were obtained from the FinnGen research project. Multivariable MR (MVMR) analysis was also conducted to determine whether the causal associations were affected by the common risk factors of DR, such as Body Mass Index, systolic blood pressure (SBP), triglycerides (TG), HDL cholesterol and hemoglobin A1c (HbA1c) levels. Results The cheese consumption (per 1-SD increase) was found to be associated with a decreased risk of DR (OR=0.701, P =0.011), PDR (OR=0.671, P =0.020), and DMP (OR=0.357, P =0.001). The MVMR analyses demonstrated that the TG level did not affect the causal associations with the decreased risks of DR and PDR. The study on DMP proved that the causal relations were independent from the effect of SBP, TG, and HbA1c levels. Conclusions Genetic evidence suggested that cheese consumption was causally associated with the decreased risk of DR. Given widespread cheese consumption, this could have significant implications for global health burdens from DR. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study did not receive any funding ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: IEU Open GWAS Project ( I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data produced in the present study are available upon reasonable request to the authors