Regional brain metabolic correlates of self-reported depression severity contrasted with clinician ratings

Abstract

Background: We compared brain-map correlations of relative cerebral glucose metabolism (rCMRglu) with psychopathologic factors derived from the self-rated Beck Depression Inventory (BDI) and factors from the clinician-rated Hamilton Depression Rating Scale (HDRS) factors, seeking an anatomic basis for differences in self and clinician ratings.

Methods: [(18)F]-FDG Positron Emission Tomography generated rCMRglu, SPM-estimated, voxel-level, brain correlation maps with BDI factor scores and HDRS factor scores in medication-free major depressive disorder.

Results: Regional brain correlates of BDI are more extensive than HDRS, even when adjusting for variance accounted for by the HDRS. Factors comprising the BDI were associated with distinct cortical and subcortical regions. The degree of overlap in factor correlation brain maps is explained by the variance shared by BDI and HDRS factor scores.

Conclusion: Self and clinician-rated aspects of depression have common and distinct neuroanatomic correlates that reflect correlations between rating scales, but correlations between glucose metabolism and self-rated depression were anatomically more extensive in this sample. Findings highlight the importance and biological underpinnings of these subjective features of major depression.

Fig. 1

Beck Depression Inventory (BDI) and Hamilton Depression Rating Scale (HDRS) total score correlations with relative regional cerebral metabolic rate for glucose (rCMRglu). Regions shown as a volume in a glass brain. Left upper panel: positive correlation with BDI. Right upper panel: negative correlation with BDI. Lower panel positive correlations with HDRS. No regions had significant negative correlations with the total HDRS score.

Fig. 2

Relative regional cerebral metabolic rate for glucose (rCMRglu) correlation with the residuals of the Beck Depression Inventory (BDI) scores while controlling for the variance explained by the Hamilton Depression Rating Scale (HDRS). The color scales in the figure indicate the strength (t score) of the correlation (t score maps are overlaid on a series of transaxial slices (2 mm apart) of a coregistered MRI scan from ~38 mm below to ~72 mm above a line connecting the anterior and posterior commissure). Red to light red regions are uniquely positively correlated with BDI total score residuals, dark to light blue regions are uniquely negatively correlated with BDI total score residuals. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)

Fig. 3

Regions shown as a volume in a glass brain. Maps of correlations of relative regional glucose metabolic rate (rCMRglu) in major depression with severity of depression as measured by the three Beck Depression Inventory (BDI)-derived factor scores.

Fig. 4

A human brain map of positive correlations of relative regional glucose metabolic rate (rCMRglu) in major depression with severity of depression as measured by factors 1, 2 and 3 derived from the Beck Depression Inventory (BDI). The color scales in the figure indicate the strength (t score) of the correlation (t score maps are overlaid on a series of transaxial slices (2 mm apart) of a coregistered MRI scan from 38 mm below to 72 mm above a line connecting the anterior and posterior commissure). Red to light red regions are uniquely positively correlated with Subjective Depression, brown to light orange regions are uniquely positively correlated with Self-Blame, blue to light blue regions are uniquely positively correlated with Somatic Complaint factor and green to light green colored areas depict regions that correlate with factors 1, 2 and/or 3. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)