Differentiation of the pattern of cognitive impairment between depressed and non-depressed patients with dementia living in long-term care facilities

Abstract

Objective: The principal objective of this study is to examine the cognitive profile of patients with dementia plus (D+ group) and without (D− group) concomitant depression.

Method: The D+ (N = 61) and D− (N = 89) patients were recruited in long-term care facilities. The depression status of the participants was determined using the Cornell Scale for Depression in Dementia. Cognitive functioning was assessed using the Hierarchic Dementia Scale (HDS).

Results: The analyses first indicated that on the total HDS score, patients of the D+ group exhibited more severe cognitive impairment compared to those of the D− group. Further analyses revealed that the difference between groups pertained to perception, attention/memory, calculation, and language functions. Moreover, secondary analyses revealed that the cognitive deficits of the D+ group were associated with behavioral (agitation and retardation, in particular), but not with mood-related, symptoms of depression. Interestingly, ideational symptoms of depression (suicide and self-depreciation, in particular) were positively correlated with cognitive impairment.

Conclusion: These findings add to those of previous studies showing that D+ and D− patients differ not only regarding the presence or absence of depressive symptoms, but also regarding cognitive manifestations. This study thus reinforces the need to detect and treat accurately depression in dementia.

Keywords:

• depression
• dementia
• cognition
• behavioral disturbances
• ideational disturbance

Acknowledgments

This research was supported through grants from the Fonds de la recherche en santé du Québec (FRSQ) and the Fondation de l’Hôpital du Saint-Sacrement. It was also supported through Investigator Awards from the FRSQ to C. Hudon and P. Voyer.

Notes

Note

1. In this study, the term depression does not refer to a clinical diagnosis. It rather refers to depressive symptoms at large and may encompasses many clinical (e.g., major depression dysthymia) or subclinical mood syndromes.