[Depression in dementia with Lewy bodies]

Area of Science:

• Neuroscience
• Gerontology
• Psychiatry

Context:

• Depression is a known risk factor and comorbidity in dementia, with higher prevalence observed in Dementia with Lewy bodies (DLB) compared to Alzheimer's disease (AD).
• Despite its clinical significance in DLB diagnosis, the precise nature and management of depression in DLB remain incompletely understood, with inconsistent findings across studies comparing AD and DLB.
• The Geriatric Depression Scale (GDS) is a validated tool for assessing depression in the elderly population.

Purpose:

• To compare the prevalence and characteristics of depression, using the Geriatric Depression Scale (GDS), between patients diagnosed with Dementia with Lewy bodies (DLB) and Alzheimer's disease (AD).
• To investigate the relationship between GDS scores and demographic/cognitive factors (age, sex, Mini-Mental State Examination) in DLB and AD patients.
• To explore the diagnostic and therapeutic implications of high GDS scores in DLB, considering the underdiagnosis and undertreatment of depression in this population.

Summary:

• DLB patients exhibited GDS scores twice as high as AD patients, indicating a significantly greater burden of depressive symptoms.
• GDS scores showed no correlation with age, sex, or cognitive function (MMSE) in either group; depression-specific symptoms were more prevalent in DLB.
• A substantial proportion of DLB patients with very high GDS scores were not formally diagnosed with depression or receiving antidepressant treatment, suggesting a diagnostic gap.

Impact:

• Findings underscore the heightened prevalence of depression in DLB and suggest it may be an integral part of a broader psychiatric syndrome in DLB, distinct from AD.
• The study highlights a critical need for systematic research into the validity, risks, and necessity of pharmacological interventions for depression in DLB.
• Understanding depression in DLB could offer novel insights into the neuropathology and psychopathology of both DLB and depression itself, guiding clinical decision-making and future therapeutic strategies.