Glomerular Hyperfiltration Predicts Kidney Function Decline and Mortality in Type 1 and Type 2 Diabetes: A 21-Year...

Area of Science:

• Nephrology
• Diabetology
• Cardiology

Background:

• Diabetic kidney disease (DKD) is a major complication of diabetes, leading to significant morbidity and mortality.
• Glomerular filtration rate (GFR) is a key indicator of kidney function, and deviations from normal, including hyperfiltration, may have prognostic implications.

Purpose of the Study:

• To assess the long-term prognostic value of glomerular hyperfiltration in patients with diabetes regarding kidney-related outcomes and mortality.
• To compare the risks associated with high (H-mGFR) and low (L-mGFR) measured GFR against normal mGFR (N-mGFR) in a diabetic cohort.

Main Methods:

• Retrospective analysis of 21-year longitudinal data from 314 patients with type 1 or type 2 diabetes.
• Glomerular hyperfiltration identified using age- and sex-specific distributions of measured GFR (mGFR) obtained via 99mTc-DTPA dynamic renal scintigraphy.
• Primary outcome: composite of doubled serum creatinine, end-stage kidney disease (ESKD), or cardiorenal death. Kidney-specific outcome: composite of doubled serum creatinine, ESKD, or renal death.

Main Results:

• Over a median of 21 years, the primary composite outcome occurred in 39.7% of H-mGFR, 38.1% of L-mGFR, and 24.5% of N-mGFR participants.
• Compared to N-mGFR, H-mGFR showed a 2.09-fold increased risk (HR 2.09; 95% CI 1.25-3.49) and L-mGFR showed a 1.81-fold increased risk (HR 1.81; 1.05-3.16) for the primary composite outcome.
• The kidney-specific composite outcome risk was significantly higher in H-mGFR (HR 4.95; 2.21-11.09) and L-mGFR (HR 3.81; 1.70-8.56) compared to N-mGFR.

Conclusions:

• Glomerular hyperfiltration, akin to hypofiltration, elevates the combined risk of kidney function decline and cardiorenal mortality in diabetic individuals.
• These findings underscore the importance of actively screening diabetic patients for subclinical kidney disease to optimize risk stratification and management.
• Proactive management strategies targeting both hyperfiltration and hypofiltration are crucial for improving long-term outcomes in patients with diabetes.