Cerebral volume measurements and subcortical white matter lesions and short-term treatment response in late life depression

Background: Late life depression is associated with volumetric reductions of gray matter and increased prevalence of subcortical white matter lesions. Previous studies have shown a poorer treatment outcome in those with more severe structural brain abnormalities. In this study, quantitative and semi-quantitative magnetic resonance imaging (MRI) measures were studied in relation to response to a 12-week controlled antidepressant monotherapy trial. Methods: MRI (1.5T) brain scans of 42 elderly inpatients with major depression, of which 23 were non-responder to a controlled 12-week antidepressant monotherapy trial, were acquired. In addition, clinical outcome was assessed after a one year period. Measures were volumes of global cerebral and subcortical structures. Results: After controlling for confounding, no differences were found between non-responders and responders after 12 weeks and after one year in volumes of cerebral gray and white matter, orbitofrontal cortex, hippocampus and white matter lesions. Conclusions: Structural brain measures associated with late life depression may not be related to short-term treatment response.