MO510: CKD Progression in a Cohort of Older Community-Dwelling Adults– Results From the Berlin Initiative Study (BIS)

Abstract

Abstract BACKGROUND AND AIMS Data on the estimated glomerular filtration rate (eGFR) over time in older populations are scarce. Identifying patterns of eGFR progression is essential for a better understanding of chronic kidney disease (CKD) in older adults. METHOD We used data from the BIS, a community-dwelling cohort of 2069 people aged 70 or older. Participants were recruited between 2009 and 2011. After baseline assessment, four follow-up visits were conducted biennially over a total observation period of 8 years. During all study visits, eGFR and CKD stages based on KIDGO guidelines were assessed using the creatinine and cystatin C-based BIS2 equation (eGFRBIS2). Additionally, we used the creatinine-based EKFC equation (eGFREKFC). In a sub-analysis, we included only non-deceased participants with complete attendance at all study visits and valid eGFR values at all measurements. RESULTS At baseline, the mean age was 80.4 years (SD = 6.7), and 52.6 % were females. Prevalence was highest for CKD stage 2 (45.4%) and 3 (49.3%). After 8 years, the prevalence for CKD stages 1 and 2 decreased, whereas stages 3 and 4 showed a consistent upward trend resulting in 18.4%, 72.4% and 8.9% of participants in stages 2, 3 and 4, respectively. Mean eGFRBIS2 decreased from 58.1 (SD = 15.2) to 48.3 (SD = 13.3) mL/min/1.73 m² after 8 years. Mean eGFREKFC showed a similar trend with estimates being slightly higher (60.4 versus 54.2 mL/min/1.73 m2 after 8 years). Same trends applied to the subgroup with complete attendance (mean age: 77.4 years). However, compared with the total population they showed a higher mean eGFRBIS2 (63.3 versus 58.1 mL/min/1.73 m²) and lower prevalence of CKD stages 3 and 4 (stage 2: 59.4 versus 45.4%; stage 3: 37.1 versus 49.3% stage 4: 1.2 versus 3.6%) at baseline. CONCLUSION We found that over the observation period of 8 years, mean eGFRBIS2 decreased by 9.8 mL/min/1.73 m2 resulting in an increasing prevalence of CKD stages 3 and 4 by 23.1 and 5.3%, respectively. This was observed in the total population as well as in the subgroup with complete study attendance.