Sex differences in brain structure in geriatric depression

In an exploratory study, authors compared patients with late-life major depression (MDD) and age-matched control subjects to examine sex differences in frontal and orbito-frontal (OFC) regional brain volumes. The study sample comprised 41 patients with MDD and 41 controls. Subjects underwent comprehensive neuropsychiatric examinations and magnetic resonance imaging (MRI) scans. Corrected frontal and OFC gray-matter volumes were compared among men and women in both groups. The depression group had lower MMSE scores, greater severity of medical burden, apathy, psychomotor retardation, and poor health-related quality of life than the controls. Men in both groups had a greater severity of medical burden, apathy, and psychomotor retardation than women. The depression group had smaller OFC total and gray-matter volumes than the controls after matching for age. Men had smaller frontal-matter volumes than women in both groups. The diagnosis x sex interaction in brain regional volumes was observed only after controlling for medical burden. Sex differences in brain neuroanatomy may be important in the pathophysiology of geriatric depression. Men may be susceptible to atrophy in frontal subregions. Medical burden may contribute to the diagnosis x sex interaction in brain regional volumes.