Qualitative magnetic resonance imaging findings in geriatric depression. Possible link between later-onset depression and Alzheimer's disease?
B. S. GREENWALD a1 , E. KRAMER-GINSBERG a1 , B. BOGERTS a1 , M. ASHTARI a1 , P. AUPPERLE a1 , H. WU a1 , L. ALLEN a1 , D. ZEMAN a1 and M. PATEL a1
a1 Division of Geriatric Psychiatry and the Brain Morphometry and Image Analysis Center, Hillside Hospital, Psychiatric Division of Long Island Jewish Medical Center, Glen Oaks, New York; the Department of Radiology, Long Island Jewish Medical Center; and the Albert Einstein College of Medicine, Bronx, New York, USA
Background. Several clinical and neuroimaging investigations support the notion that underlying brain changes may relate to depression in older patients, especially those with a later-age initial episode. However uncertainty still exists about diagnostic and pathogenic significance of structural brain abnormalities in aged depressives, in part because many studies lack all-elderly and age-similar normal comparison populations.
Methods. Brain morphology of elderly depressives (N = 30) and normal controls (N = 36) was compared by assessing magnetic resonance imaging (MRI) brain scans with qualitative criteria-based scales. Ratings included lateral and third ventricle enlargement, and cortical, medial temporal, and caudate atrophy.
Results. Significant differences between depressed and control groups were not demonstrated. Later-onset depressives had significantly more left medial temporal and left caudate atrophy than early-onset counterparts of similar age. Medial temporal atrophy significantly correlated with cognitive impairment and was not related to physical illness. Depressives with medial temporal atrophy (N = 7) were older and had later age at onset of depression than those without such changes. Cerebrovascular disease risk factors did not predict MRI abnormalities.
Conclusions. Results indicate non-specificity and lack of homogeneity of qualitatively measured structural brain changes in geriatric depression, but suggest that pathology of specific, lateralized brain regions may be implicated in some later-onset patients. The relationship between medial temporal atrophy and late-onset depression raises the possibility that such patients may suffer from as-yet undeclared Alzheimer's disease. Lack of association between cerebrovascular disease risk factors and brain changes suggests other pathophysiological contributions.
Address for correspondence: Dr Blaine S. Greenwald, Division of Geriatric Psychiatry, Research Building – Hillside Hospital, 75–579 263rd Street, Glen Oaks, New York, NY 11004, USA.