Regional cortical gray matter thickness differences associated with type 2 diabetes and major depression

Abstract

The purpose of this study was to examine the effect of type 2 diabetes with major depression on cortical gray matter using magnetic resonance imaging and cortical pattern matching techniques. We hypothesized that diabetic subjects and depressed diabetic subjects would demonstrate decreased cortical gray matter thickness in prefrontal areas as compared to healthy control subjects. Patients with type 2 diabetes (n=26) and patients with diabetes and major depression (n=26) were compared with healthy controls (n=20). Gray matter thickness across the entire cortex was measured using cortical pattern matching methods. All subjects with diabetes demonstrated decreased cortical gray matter thickness in the left anterior cingulate region. Additionally, depressed diabetic subjects showed significant cortical gray matter decreases in bilateral prefrontal areas compared with healthy controls. Correlations between clinical variables and cortical gray matter thickness revealed a significant negative relationship with cerebrovascular risk factors across all three groups, most consistently in the left dorsomedial prefrontal cortex. A significant positive relationship between performance on attention and executive function tasks and cortical gray matter thickness predominantly in left hemisphere regions was also seen across all subjects. Depression and diabetes are associated with significant cortical gray matter thinning in medial prefrontal areas.

Conflict of interest statement

Disclosure/Conflict of Interest

The author(s) declare that, except for income received from my primary employer, no financial support or compensation has been received from any individual or corporate entity over the past three years for research or professional service and there are no personal financial holdings that could be perceived as constituting a potential conflict of interest.

Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Figures

Figure 1. Effect of Diagnosis on Cortical Gray Matter Thickness

Top row: Diabetic subjects demonstrated cortical gray matter thinning particularly in the left anterior cingulate compared to healthy controls, but this result did not hold up after permutation testing. Bottom row: Depressed diabetic subjects show cortical thinning in the medial superior frontal regions. HC: Healthy control subjects, DC: Diabetic control subjects, DD: Depressed diabetic subjects (uncorrected images shown)

Figure 2. Correlation between Cortical Gray Matter Thickness and CVRF

Uncorrected partial correlation map of cortical gray matter differences associated with stroke risk (CVRF). HC: Healthy control subjects (FDR=.247), DC: Diabetic control subjects (FDR=.11), DD: Depressed diabetic subjects (FDR=.078), Total: All subjects (FDR=.0093).

Figure 3

Figure 3A. Correlation of Cortical Gray Matter Thickness with Attention Processing. Uncorrected partial correlation maps showing cortical gray matter thickness associated with performance on attention processing tasks. HC: Healthy control subjects (FDR=.0145), DC: Diabetic control subjects (FDR=.993), DD: Depressed diabetic subjects (FDR=.139), Total: All subjects (FDR = 0.021) Figure 3B. Correlation of Cortical Gray Matter Thickness with Executive Function: Uncorrected partial correlation maps showing cortical gray matter thickness associated with performance on executive function tasks. HC: Healthy control subjects (FDR=.0265), DC: Diabetic control subjects (FDR=.999), DD: Depressed diabetic subjects (FDR=.103), Total: All subjects (FDR=.0182)

Figure 3

Figure 3A. Correlation of Cortical Gray Matter Thickness with Attention Processing. Uncorrected partial correlation maps showing cortical gray matter thickness associated with performance on attention processing tasks. HC: Healthy control subjects (FDR=.0145), DC: Diabetic control subjects (FDR=.993), DD: Depressed diabetic subjects (FDR=.139), Total: All subjects (FDR = 0.021) Figure 3B. Correlation of Cortical Gray Matter Thickness with Executive Function: Uncorrected partial correlation maps showing cortical gray matter thickness associated with performance on executive function tasks. HC: Healthy control subjects (FDR=.0265), DC: Diabetic control subjects (FDR=.999), DD: Depressed diabetic subjects (FDR=.103), Total: All subjects (FDR=.0182)