ABSTRACT
BACKGROUND/AIMS: We conducted a 3-year longitudinal study concerning factors associated with changes in brain atrophy in elderly diabetic patients. METHODS: We evaluated hippocampal and global brain atrophy using automatic voxel-based morphometry of structural magnetic resonance images, 4 cognitive function tests, and cerebral small vessel disease (SVD) in 66 diabetic patients. RESULTS: During the 3-year follow-up, hippocampal and global brain atrophy advanced, and cognitive functions worsened. For changes in hippocampal atrophy, changes in estimated glomerular filtration rate (eGFR), albuminuria, and being an ApoE ε4 carrier were independent factors; change in the number of silent brain infarctions was an independent factor for changes in global brain atrophy. A significant association of changes in eGFR and albuminuria with hippocampal atrophy remained after adjusting for confounders including SVD. Both types of brain atrophy at baseline were significantly correlated with cognitive impairment at baseline and especially associated with changes in delayed word recall during the follow-up after adjusting for confounders. CONCLUSION: Changes in eGFR and albuminuria during follow-up were independent risk factors for hippocampal atrophy, which was associated with decline in delayed word recall, suggesting that management of chronic kidney disease may prevent the progression of hippocampal atrophy.
ABSTRACT
AIMS/INTRODUCTION: We investigated the effect of renal impairment on cognitive function during a 3-year follow up in elderly type 2 diabetic patients, and an association with microinflammation. MATERIALS AND METHODS: Four cognitive function tests - Mini-Mental State Examination (MMSE), word recall, Digit Symbol Substitution (DSS) and Stroop Color Word - were carried out in 67 patients. Renal impairment was defined as the presence of albuminuria and a decline in estimated glomerular filtration (eGFR) <60 mL/min/1.73 m(2). Inflammatory markers, such as highly sensitive C-reactive protein (hs-CRP), tumor necrotizing factor-α (TNF-α), interleukin (IL)-1ß and IL-6, were measured at baseline. RESULTS: At baseline, cognitive decline was found in patients with renal impairment. The DSS test was independently associated with eGFR decline, whereas MMSE tended to be associated with albuminuria after adjusting for confounding factors. Regarding changes in cognitive function and renal impairment, changes in urinary albumin to creatinine ratios were strongly and independently associated with changes in word recall scores. In patients with persistent eGFR decline, there was a tendency toward a greater decrease in MMSE and DSS scores, whereas in those with newly detected albuminuria, there was a tendency toward a greater decrease in word recall scores. Increased baseline levels of hs-CRP, TNF-α and IL-6 were associated with renal impairment and cognitive function, especially DSS tests, respectively. However, the increased levels were not independent predictors for cognitive decline. CONCLUSIONS: The present study showed a reciprocal relationship between cognitive decline and renal impairment, especially progression of albuminuria. Thus, monitoring treatment using renal biomarkers will be important for preserving both renal and cognitive function.
ABSTRACT
AIMS: We conducted a 3-year longitudinal study concerning an association between cognitive function and cerebral small vessel disease (SVD) seen on magnetic resonance imaging (MRI) in elderly type 2 diabetic patients. METHODS: Four cognitive function tests--MMSE, word recall, Digit Symbol Substitution (DSS), and Stroop Color Word (Stroop)--were performed in 67 diabetic patients twice in 2006 and 2009. SVD was diagnosed as silent brain infarct (SBI) and white matter lesions (WMLs) according to MRI. RESULTS: Number of SBI was significantly correlated with a decline in DSS and Stroop tests, while WMLs grade was only associated with it in DSS tests after adjustment for age, gender, education years, the presence of hypertension and dyslipidemia, and smoking. Severity of SVD at baseline was stronger associated with cognitive function after the 3-year follow-up than at baseline. WMLs progression was associated with more rapid decline of DSS tests compared to a group without progression. CONCLUSIONS: SVD seen on MRI is a good marker for predicting future cognitive decline, and monitoring of treatment through the use of such markers is expected to maintain a good quality of life for elderly diabetic patients.
