Study Protocol- The impact of social deprivation on development and progression of diabetic kidney disease

Introduction Diabetes is one of the leading causes of chronic kidney disease. Social deprivation is recognised as a risk factor for complications of diabetes, including diabetic kidney disease. The effect of deprivation on rate of decline in renal function has not been explored in the Irish Health System to date. The objective of this study is to explore the association between social deprivation and the development/progression of diabetic kidney disease in a cohort of adults living with diabetes in Ireland. Methods and analysis This is a retrospective cohort study using an existing dataset of people living with diabetes who attended the diabetes centre at University Hospital Galway from 2012 to 2016. The variables included in this dataset include demographic variables, type and duration of diabetes, clinical variables such as medication use, blood pressure and BMI and laboratory data including creatinine, urine albumin to creatinine to ratio, haemoglobin A1c and lipids. This dataset will be updated with laboratory data until January 2023. Individual’s addresses will be used to calculate deprivation indices using the Pobal Haase Pratschke (HP) deprivation index. Rate of renal function decline will be calculated using linear mixed-effect models. The relationship between deprivation and renal function will be assessed using linear regression (absolute and relative rate of renal function decline based on eGFR) and logistic regression models (rapid vs. non-rapid decline). Ethics and dissemination Ethical approval has been granted by the clinical research ethics committee of Galway University Hospitals- Ref C.A. 2956. Results will be presented at conferences and published in peer review journals. ### Competing Interest Statement CC received funding to attend national and international diabetes conferences from Novo Nordisk. TPG received honoraria for speaker fees and/or advisory boards from Novo Nordisk, Sanofi Aventis, Mundipharma Pharmaceuticals, Dexcom, Abbott Diabetes Care, AbbVie, Astra Zeneca and Eli Lilly. ### Funding Statement The author(s) received no specific funding for this work. ### 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: Ethical approval has been granted by the clinical research ethics committee of Galway University Hospitals- Ref C.A. 2956. 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 Deidentified research data will be made publicly available when the study is completed and published.