Abnormal Hippocampal Subfields May Be Potential Predictors of Worse Early Response to Antidepressant Treatment in Drug-Naïve Patients With Major Depressive Disorder.

BACKGROUND

Previous studies had proved that hippocampal volume has predictive value for antidepressant response in patients with major depressive disorder (MDD). However, the exact subregion of the hippocampus relevant to the predictive role of antidepressants response is not known.

PURPOSE

To explore which hippocampal subfield volumes might predict an early response to first-time use of antidepressants in drug-naïve MDD patients.

STUDY TYPE

Prospective.

POPULATION

Thirty-eight drug-naïve MDD patients (mean illness duration = 1.6 years) and 55 healthy control subjects (HCS).

FIELD STRENGTH/SEQUENCE: 3.0T MRI, T -weighted, 3D, SPGR sequence.

ASSESSMENT

The hippocampal subfields and total intracranial volume were measured with FreeSurfer. The response to antidepressants was evaluated by the reduction rate of the Hamilton Rating Scale for Depression score (RRS) after a 6-week routine clinical antidepressant treatment.

STATISTICAL TESTS

The relationship between hippocampal subfield volumes and RRS was explored using partial correlation analysis. Volume differences among early responding patients (ERP), nonresponding patients (NRP), and HCS were examined by multivariate analysis of covariance. Receiver operating characteristic (ROC) curve analysis was used to evaluate the sensitivity and specificity of volumes as predictors.

RESULTS

NRP had significantly larger volumes than both ERP and HCS in bilateral subiculum, cornu ammonis (CA) 1 and left CA2/3, CA4/dentate gyrus (DG) (all P < 0.01, false discovery rate corrected). Significant negative correlations were found between the RRS and volumes of left subiculum (P = 0.004), CA2/3 (P = 0.008), and CA4/DG (P = 0.004) in the whole MDD group. ROC analysis demonstrated that the left subiculum exhibited the highest accuracy for differentiating NRP from ERP, with a sensitivity of 76.9% and specificity of 80%.

DATA CONCLUSION

These findings propose that volumes of certain hippocampal subfields may be associated with antidepressant treatment and this has potential use in clinical applications for treatment selection in patients with MDD at an early stage.

LEVEL OF EVIDENCE

2 Technical Efficacy: Stage 4 J. Magn. Reson. Imaging 2019;49:1760-1768.