The relationship between intellectual impairment and mood disorder in the first year after stroke

In a community-based study of patients with a first-ever stroke, intellectual impairment (as defined by scores on a common screening test for dementia, the Mini-Mental State Examination) was found in 26% at 1 month post-stroke, and in 21% at 6 and 12 month follow-up. Low scores on the screening test were associated with greater age, physical disability before the stroke, larger stroke lesion volumes as measured on CT scan, and non-stroke changes such as atrophy and white matter low attenuation on the CT scan. There was a negative correlation between scores on the Mini-Mental State Examination and symptom levels on two measures of mood disorder. However, there was no evidence of a specific relationship between major depression and low scores on the Mini-Mental State. We examined various aspects of the relationship between mood symptoms and low scores on the Mini-Mental State, but found no evidence to support the suggestion that this relationship represented an example of depressive pseudodementia. We discuss the significance of our findings for clinical psychiatry and neuropsychology.