eGFR decline greater with albuminuria plus normal renal function than nonalbuminuric CKD in diabetes
Among a cohort of adults with type 2 diabetes, estimated glomerular filtration rate fell to a lesser degree among those with chronic kidney disease and no albuminuria vs. those without CKD and those with albuminuria. Furthermore, end-stage renal disease risk was not different between adults with CKD and no albuminuria and those without CKD, according to findings published in Diabetes Care.
“People with albuminuric CKD have significant risk of progression to end-stage kidney disease and have increased all-cause and cardiovascular mortality,” Jonathan E. Shaw, MD, MRCP, FRACP, a National Health and Medical Research Council (NHMRC) senior research fellow and consultant physician at the department of clinical diabetes and epidemiology at the Baker Heart and Diabetes Institute in Melbourne, Australia, and colleagues wrote. “However, the risk of progression of nonalbuminuric renal impairment in diabetes has not been investigated thoroughly. Thus, the clinical and prognostic implications of this phenotype remain unclear.”
Shaw and colleagues collected data on urine albumin-to-creatinine ratio and eGFR in 10,185 participants in the ACCORD and ACCORDION studies (mean age, 62 years; 38.5% women). The researchers also identified instances of an eGFR of 15 mL/min/1.73 m2 or ESRD, all-cause mortality and major adverse cardiovascular events across 5 years of median follow-up in the ACCORD study and 8.8 years of median follow-up in the ACCORDION study.
Researchers defined albuminuria as a urine albumin-to-creatinine ratio of 3.4 mg/mmol or more and CKD as an eGFR of less than 60 mL/min/1.73m2.
At baseline, 28.1% of participants had albuminuria and no CKD, 4.3% haf CKD but no albuminuria, 3.4% had both CKD and albuminuria. Participants with CKD and no albuminuria lost 1.1% of eGFR each year; those with an eGFR of 90 mL/min/1.73 m2 to 120 mL/min/1.73 m2 and without CKD lost 1.24% of eGFR per year; those with albuminuria but without CKD lost 2.6% per year; and those with albuminuria and CKD lost 3.2% per year.
Participants with albuminuria and CKD and participants with albuminuria without CKD had heightened risk for ESRD (HR = 4.52; 95% CI, 2.91-7.01 and HR = 1.72; 95% CI, 1.27-2.34, respectively), all-cause mortality (HR = 2.38; 95% CI, 1.92-2.9 and HR = 1.82; 95% CI, 1.59-2.08, respectively) and major adverse CV events (HR = 2.37; 95% CI, 1.89-2.97 and HR = 1.88; 95% CI, 1.63-2.16, respectively) vs. participants without CKD and with an eGFR between 90 mL/min/1.73 m2 and 120 mL/min/1.73 m2. Participants with CKD without albuminuria did not have significantly different ESRD risk vs. participants without CKD and with an eGFR between 90 mL/min/1.73 m2 and 120 mL/min/1.73 m2 while the risks for all-cause mortality (HR = 1.42; 95% CI, 1.14-1.78) and major adverse CV events (HR = 1.44; 95% CI, 1.13-1.84) were increased.
“Our study demonstrated that those with nonalbuminuric CKD have a slower rate of decline in eGFR than did any other group, including those with normal renal function, suggesting the presence of renoprotective factors,” the researchers wrote. “However, these individuals still carry a greater risk for all-cause mortality and major adverse CV events than do those with normal renal function. With increasingly prevalent nonalbuminuric CKD in diabetes, more studies are warranted to clarify its underlying mechanisms or pathogenesis.” – by Phil Neuffer
Disclosures: The authors report no relevant financial disclosures.