Ak. Berger et al., The occurrence of depressive symptoms in the preclinical phase of AD - A population-based study, NEUROLOGY, 53(9), 1999, pp. 1998-2002
Objective: To examine preclinical depressive symptoms 3 years before the di
agnosis of AD. Methods: The authors compared incident AD patients and nonde
mented individuals in terms of baseline mood- and motivation-related sympto
ms of depression, and assessed whether depressive symptoms in preclinical A
D are related to self-perceived memory problems. Participants came from a p
opulation-based longitudinal study on aging and dementia in Stockholm, Swed
en. The sample consisted of 222 persons older than 74 years who were follow
ed for a 3-year interval. Thirty-four individuals had developed AD at follo
w-up, whereas 188 remained nondemented. Dementia diagnosis was made accordi
ng to the criteria of the Diagnostic and Statistical Manual of Mental Disor
ders, 3rd edition, revised. Depressive symptoms were assessed by the Compre
hensive Psychopathological Rating Scale. Results: The incident AD patients
had more depressive symptoms than the nondemented persons at baseline. Ther
e was a dominance of motivation-related symptoms of depression (e.g., lack
of interest, loss of energy, concentration difficulties) in preclinical AD.
This association remained when adjusting for subjective memory complaints.
Conclusions: Depressive symptoms are elevated preclinically in AD, and thi
s elevation is not merely a by-product of self-perceived cognitive difficul
ties. Thus, depressive symptoms may be part of the preclinical phase in AD.