BMJ Open (Sep 2024)
Cohort profile: the PRIMETIME 1 (PRecIsion MEdicine based on kidney TIssue Molecular interrogation in diabetic nEphropathy) cohort – a longitudinal Danish nationwide study of individuals with diabetes and a performed kidney biopsy
Abstract
Purpose Individuals with diabetes and chronic kidney disease are at high risk of kidney failure, cardiovascular events and premature mortality and more research is warranted to further improve the prevention and management of complications. The PRecIsion MEdicine based on kidney TIssue Molecular interrogation in diabetic nEphropathy (PRIMETIME) 1 cohort is designed to study clinical characteristics, diagnostic accuracy and prognostic markers in a population with diabetes and kidney disease classified by biopsy.Participants This retrospective Danish nationwide cohort includes 2586 individuals with diabetes who have undergone a kidney biopsy between the 1980s and 2022.Findings to date By combining multiple registries and medical databases, we comprehensively describe the cohort with data on demographics, socioeconomic status, lifestyle, laboratory measurements, medication use and comorbidity at the time of diagnosis of diabetes and at the time of kidney biopsy within types of kidney disease. In individuals with type 1 diabetes, 132 cases of diabetic nephropathy were identified, with 70.5% of them being men, with a median (IQR) age of 50 (41–59) years at biopsy, and a median (IQR) estimated glomerular filtration rate (eGFR) 37 (23–5X) mL/min/1.73 m2. Among individuals with type 2 diabetes and diabetic nephropathy (n=599), 76.8% were male aged 61.9 (55–99) years at biopsy and with an eGFR 40 (24–6X) mL/min/1.73 m2.Future plans The national population registries in Denmark provide a long follow-up period and a distinct opportunity to use superior registry data. This cohort offers a unique opportunity to study the prognostic value of findings in kidney biopsies, the impact of comorbidity and the effect of therapy at the time of kidney biopsy, with a follow-up period increasing over time with running updates.