Cerebral haemodynamics and depression in the elderly

Area of Science:

• Neuroscience
• Gerontology
• Psychiatry

Background:

• Epidemiological and neuroimaging studies suggest a link between cerebrovascular disease and depression in the elderly.
• The precise contribution of cerebrovascular factors to the pathogenesis of late-life depression remains unclear.

Purpose of the Study:

• To investigate the relationship between cerebral hemodynamics and depression in a population-based cohort.
• Utilized transcranial Doppler ultrasonography to assess cerebral blood flow and reactivity.

Main Methods:

• Measured middle cerebral artery blood flow velocity and CO2-induced vasomotor reactivity in 2093 participants of the Rotterdam Study.
• Screened for depressive symptoms using the Center for Epidemiological Studies Depression scale; diagnosed depressive and subthreshold depressive disorders via semistructured interviews.
• Controlled for age, sex, stroke, cognitive score, and cardiovascular risk factors in analyses of covariance.

Main Results:

• Individuals with depressive symptoms exhibited reduced blood flow velocities and lower vasomotor reactivity.
• Blood flow velocity was significantly lower in subjects with DSM-IV depressive disorder.
• Reduced CO2-induced vasomotor reactivity was primarily observed in subjects with subthreshold depressive disorder.

Conclusions:

• Late-life depression is associated with measurable cerebral hemodynamic changes, detectable via transcranial Doppler ultrasonography.
• Reduced cerebral blood flow velocity may reflect reduced demand in severe depression (DSM-IV disorder).
• Impaired CO2-induced vasomotor reactivity could be a causal factor in subthreshold depressive disorder.