Depression in Older Adults May Be Linked to Memory Loss
In a study published in the journal Neurology, researchers Zeki Al Hazzour, Michelle R. Caunca, Juan Carlos Nobrega, and others showed that depression in older adults correlates to worse baseline episodic memory, whole brain atrophy, and an increased risk of having subclinical brain infarcts (ie, areas of tissue loss from lack of oxygen, most likely resulting from undetected transient ischemic attacks, or ministrokes.)
Subjects of the study were recruited from a cohort of adults living in Northern Manhattan; 52% of that cohort were Caribbean Hispanic individuals. Those selected for the study were age 50 and older (mean age 71), had no history of clinically-evident stroke, and no contraindications for MRI. All individuals in the study underwent cognitive and mood assessments. Presence of depressive symptoms was measured with the Center for Epidemiologic Studies-Depression scale (CES-D). A total of 888 individuals who an MRI both at the initial assessment and 5 years later comprised the final subject pool.
At the initial assessment, individuals were categorized as having (CES-D 16) or not having depressive symptoms (CES-D <16). Those with depressive symptoms (22%) were more likely to be female, Hispanic, uninsured or on Medicaid, and taking antidepressants, and less likely to engage in leisure-time physical activity or report moderate alcohol use. They also had a lower mean number of years of education.
After adjustment for sociodemographic measures, behavioral and vascular risk factors, and use of antidepressants, subjects with depressive symptoms had lower scores on tests of episodic memory (P = .0003) compared to subjects without depressive symptoms. Those with depressive symptoms also had smaller intracranial volumes (P = .04) and higher incidence of occult infarcts (P = .05) at baseline. All 3 differences found were still present 5 years later but had not increased longitudinally.
“Small vascular lesions in the brain are markers of small vessel disease, a condition in which the walls in the small blood vessels are damaged,” said Zeki Al Hazzouri. “Our research suggests that depression and brain aging may occur simultaneously, and greater symptoms of depression may affect brain health through small vessel disease.”