Association of Disease Severity with Longitudinal Changes in Gray Matter Volume in Individuals Diagnosed with Major Depressive Disorder

To investigate individual gray matter volume (GMV) trajectories in patients with Major Depressive Disorder (MDD) over a period of up to 10 years.

Study Design: A case-control study utilizing the Münster Neuroimaging Cohort, with participants undergoing 3 to 6 MRI assessments at approximately 2-year intervals.
Participants: Individuals of Western European ancestry diagnosed with MDD and healthy controls were recruited, with patients receiving inpatient treatment at the time of initial recruitment.
Assessment Methods: Clinical assessments and neuroimaging were conducted to evaluate GMV in specific brain regions, focusing on cumulative illness severity and acute depressive state.
Hypotheses: Three hypotheses were prespecified regarding GMV decline in MDD patients compared to controls, the relationship between cumulative illness severity and GMV decline, and the dynamic association of acute depressive state with GMV.

Longitudinal studies indicate that GMV alterations in MDD vary over time, with some studies showing progressive decline linked to failed remission and relapse.
Other research suggests dynamic, state-dependent changes in GMV during depressive episodes.
This study aims to clarify whether GMV changes are progressive or dynamic by examining individual trajectories over an extended period.

This study seeks to differentiate between progressive and dynamic changes in GMV associated with MDD.

Limited number of prospective studies with methodological constraints.
Most longitudinal investigations have only 2 MRI assessments and focus on single clinical variables.
Heterogeneity in MDD course complicates the establishment of a cohesive neurobiological model.

This study aims to enhance understanding of GMV trajectories in MDD.