Referral rate of chronic kidney disease patients to a nephrologist in the Region of Southern Denmark: results from KidDiCo.

Background: Data on the referral rate of chronic kidney disease (CKD) patients to specialists are sparse. Investigating referral rates and characterizing patients with kidney disease not followed by a nephrologist are relevant for future measures in order to optimize public health and guideline implementation. Methods: Data were extracted from the Kidney Disease Cohort of Southern Denmark (KidDiCo). Referral rates for all incident CKD patients below 60 mL/min/1.73 m² and referral rates according to the KDIGO guidelines based on glomerular filtration rates below 30 mL/min/1.73 m² were calculated. Information on contact with one of the nephrologist outpatient clinics in the Region of Southern Denmark was collected from the Danish National Patient Registry. The individual follow-up time for nephrology contact was 12 months. Additional data were accessed via the respective national databases. CKD patients on dialysis and kidney transplanted patients were excluded. Results: A total of 3% of patients with an eGFR <60 mL/min/1.73 m²-16% of patients with an eGFR <30 mL/min/1.73 m² and 35% of patients with an eGFR <15 mL/min/1.73 m² were in contact with a nephrologist in the outpatient settings. Younger age, male sex, diabetes, hypertension, higher education and proximity to a nephrology outpatient clinic increased the chance of nephrology follow-up. Conclusion: Only a small fraction of CKD patients are followed by a nephrologist. More studies should be performed in order to find out which patients will profit the most from renal referral and how to optimize the collaboration between nephrologists and general practitioners.