Brain MRI Volume Findings in Diabetic Adults With Albuminuria: The ACCORD-MIND Study

BACKGROUND: Albuminuria is associated with cognitive impairment in people with type 2 diabetes mellitus (T2DM). The brain volume correlates of albuminuria in people with T2DM have not been well investigated. METHODS: We examined 502 individuals with T2DM (9-12 years duration; mean age ~62 years) who had a brain MRI at baseline and at 40 months. Baseline MRI findings were examined by the presence or absence of albuminuria (≥30mg/g creatinine). Changes in MRI findings were examined by whether albuminuria was persistent, intermittent, or absent during follow-up. RESULTS: At baseline, participants with albuminuria (28.7% of the cohort) had more abnormal white matter volume (AWMV) than participants without albuminuria on unadjusted analysis. This difference was attenuated with adjustment for systolic blood pressure, which was higher in participants with albuminuria than in those without albuminuria. During ~3.5 years of follow-up, participants with persistent albuminuria (15.8%) had a greater increase in new AWMV than participants without albuminuria (59.8%) or those with intermittent albuminuria on unadjusted analysis. This difference was attenuated with adjustment for age and systolic blood pressure. There were no significant differences in gray matter volume and total brain volume between participants with or without albuminuria at baseline or during follow-up. There was no significant effect modification of these findings by estimated glomerular filtration rate (eGFR) at baseline or change in eGFR during follow-up. CONCLUSIONS: In this diabetic cohort, baseline albuminuria and persistent albuminuria were not independently associated with any significant differences in brain volume measurements compared with participants without albuminuria.