Participants with CKD had significantly poorer processing speed and working memory….
Both type 2 diabetes and chronic kidney disease (CKD) have been associated with structural brain changes. In previous studies, people with type 2 diabetes have been shown to have reduced total gray matter and WM volume, as well as more focal regional patterns of cerebral volume loss, including involvement of the hippocampus. However, the relationship between CKD and cerebral structural changes are still not fully understood.
Researchers from the Wake Forest School of Medicine, Winston-Salem, NC, examined the relationship between urine albumin:creatinine ratio (UACR), estimated glomerular filtration rate (eGFR), and cerebral MRI volumes in 263 African Americans with type 2 diabetes.
In this cross-sectional study, the participants’ renal parameters, white matter (WM), gray matter (GM), hippocampal, and WM lesion (WML) volumes were measured using generalized linear models. This model included adjustments for age, education, sex, BMI, hemoglobin, A1C level, and hypertension. Among participants, 62.7% were female with a mean age of 60.2 years old.
Mean diabetes duration was 14.3 years, HbA1C level was 8.2% (2.2%; 66 mmol/mol), eGFR was 86.0 mL/min/1.73 m2 (23.2 mL/min/1.73 m2), and UACR was 155.8 mg/g (542.1 mg/g; median 8.1 mg/g).
Chronic kidney disease (eFGR 30 mg/g) had smaller GM and higher WML volumes. Higher UACR was significantly associated with higher WML volume and larger cerebrospinal fluid volumes, smaller GM and hippocampal WM volumes. A higher eGFR was associated with larger hippocampal WM volumes.
Consistent with higher WML volumes, participants with CKD had significantly poorer processing speed and working memory. These findings were independent of glycemic control.
The authors concluded that, “We found albuminuria to be a better marker of cerebral structural changes than eGFR in AAs with type 2 diabetes. Relationships between albuminuria and brain pathology may contribute to poorer cognitive performance in patients with mild CKD.”
- Albuminuria was a better marker of cerebral structural changes than eGFR in African Americans with type 2 diabetes.
- Albuminuria and reduced kidney function may contribute to declining cognitive performance.
- More studies are necessary to support these results.
Sink KM, Divers J, Whitlow CT, et al. Cerebral Structural Changes in Diabetic Kidney Disease: African American- Diabetes Heart Study MIND. Diabetes Care 2015; 38:206-212