Pathological Correlations of Neuropsychiatric Symptoms in Institutionalized People with Dementia

Abstract

Background:

Comprehensive clinicopathological studies of neuropsychiatric symptoms (NPS) in dementia are lacking.

Objective:

To describe the pathological correlations of NPS in a sample of institutionalized people with dementia.

Methods:

We studied 59 people who were consecutively admitted to a nursing home and donated their brain. Correlations between pathological variables and NPS upon admission (n = 59) and at one-year follow-up assessment (n = 46) were explored and confirmed using bivariate and multivariate statistical methods.

Results:

Mean (SD) age at admission was 83.2 (6.4) years and mean (SD) age at demise was 85.4 (6.6); 73% of the subjects were female and 98% presented advanced dementia. The most frequent etiological diagnosis was Alzheimer’s disease (AD; 74.6% clinical diagnosis, 67.8% pathological diagnosis). The pathological diagnosis of AD was associated with aggression (β _est 0.31), depression (β _est 0.31), anxiety (β _est 0.38), and irritability (β _est 0.28). Tau stage correlated with aggressive symptoms (β _est 0.32) and anxiety (β_est 0.33). Coexistence of AD and Lewy body pathology was associated with depression (β _est 0.32), while argyrophilic grains were associated with eating symptoms (β _est 0.29). Predictive models were achieved for apathy, including cognitive performance, basal ganglia ischemic lesions, and sex as predictors (R² 0.38) and for sleep disorders, including pathological diagnosis of AD and age at demise (R² 0.18) (all p-values <0.05, unadjusted).

Conclusion:

AD was the main pathological substrate of NPS in our sample of very elderly people with advanced dementia. However, correlations were mild, supporting a model of focal/asymmetric rather than diffuse brain damage, along with relevance of environmental and other personal factors, in the genesis of those symptoms.