Kidney Week

Abstract: FR-PO878

Estimated Glomerular Filtration Rate Thresholds Associated with Poor Long-Term Outcomes in the Elderly with Diabetes

Session Information

• Geriatric Nephrology
  November 03, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Geriatric Nephrology

• 1300 Geriatric Nephrology

Authors

• Lee, Kyungho, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea (the Republic of)

Kyungho Lee,

• Hwang, Subin, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea (the Republic of)

Subin Hwang,

• Jeon, Junseok, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea (the Republic of)

Junseok Jeon,

• Jang, Hye Ryoun, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea (the Republic of)

Hye Ryoun Jang,

• Huh, Wooseong, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea (the Republic of)

Wooseong Huh,

• Kim, Yoon-Goo, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea (the Republic of)

Yoon-Goo Kim,

• Lee, Jung eun, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea (the Republic of)

Jung eun Lee,

Background

Age-adapted estimated glomerular filtration rate (eGFR)-based chronic kidney disease (CKD) criteria was recently proposed, which has been supported by the fact that mortality risks start to increase at GFR <45 mL/min/1.73m² in the elderly. However, the eGFR threshold for mortality and kidney outcomes in elderly with diabetes was less understood. We aimed to evaluate eGFR categories that raise the risk of mortality and end-stage kidney disease (ESKD) by age group, using an 8-year follow-up cohort of elderly diabetic patients.

Methods

Elderly patients (≥65 years) with type 2 diabetes who visited our outpatient diabetes center during 2009 were identified and followed up until 2017. Patients were categorized into four groups per their CKD-EPI equation-based eGFR: ≥60, 45 to 59, 30 to 44, and 15 to 29 mL/min/1.73m². Cox proportional hazard model for all-cause mortality and competing-risk analysis for ESKD (with a competing event of pre-ESKD death) were performed.

Results

Among 3,065 subjects, 19%, 8%, and 2% patients had eGFR 45 to 59, 30 to 44, and 15 to 29 mL/min/1.73m² at baseline, respectively. After adjusting multiple clinical covariates, including blood pressure, diabetes duration, urine albumin/creatinine ratio, HbA1c, serum cholesterol levels, and comorbidity index, patients with eGFR 30 to 44 and 15 to 29 mL/min/1.73m² had 1.51-fold (95% CI 1.17–1.95, P <.001) and 2.66-fold (1.87–3.79, P <.001) greater risks of death, respectively, whereas patients with eGFR 45 to 59 mL/min/1.73m² had a comparable risk (1.18, 0.96–1.45, P = 0.127) to those with eGFR ≥60 mL/min/1.73m². Substitution hazard ratios for ESKD were 2.29 (1.41–3.71, P = 0.001), 5.25 (3.27–8.41, P <.001), and 16.74 (9.73–28.80, P <.001) in patients with eGFR 45 to 59, 30 to 44, 15 to 29 mL/min/1.73m², respectively. In a subgroup of patients 75 or older (n=800), patients with eGFR 45 to 59 mL/min/1.73m² showed comparable risks for both ESKD and mortality, and ESKD risk started to increase from eGFR <45 mL/min/1.73m².

Conclusion

Reduced eGFR <60 mL/min/1.73m² predicted an increased risk of ESKD in elderly diabetic patients, suggesting that the current traditional eGFR threshold appears feasible. However, in patients ≥75 years, eGFR ranging from 45 to 59 mL/min/1.73m² had little effect on long-term outcomes for both mortality and ESKD.