Abstract :
many patients develop psychiatric and behavioral disturbances in the course of
Alzheimer’s disease (Ad). Among these disturbances, depressive symptoms are frequent and affect nearly 40%
of patients. the natural history and course of such symptoms in Ad, and in particular the predictive factors, are
little known. We studied the incidence and risk factors for the development of the first depressive symptoms in
Ad. Design: multicenter prospective study. Participants: three hundred twelve Ad patients from the French
network on Ad (reAL.Fr) without depression and without antidepressant treatment at baseline were followed
up and assessed every 6 months for 4 years. during follow-up, all events occurring between two visits were
carefully recorded. Measurements: We used the neuropsychiatric inventory (npi) for comprehensive evaluation
of behavioral and psychological symptoms and depressive symptoms in particular. A multivariate analysis was
performed using a backward stepwise Cox proportional hazards model. Results: the incidence of depressive
symptoms was 17.45% person/years, 95%Ci (13.88-21.02). Among non-time dependent variables, duration of
disease (rr=0.51; 95%Ci: 0.30-0.85, p=0.0102) and the number of comorbid conditions (rr=0.45; 95%Ci:
0.24-0.83, p=0.0115) were protective factors against the development of depressive symptoms.
Agitation/aggression (rr=1.96; 95%Ci: 1.19-3.23, p=0.0078) and sleep disturbances (rr=2.65; 95%Ci: 1.40-
5.00, p=0.0026) were time-dependent variables predictive of depressive symptoms. Conclusion: better
knowledge of predictive factors of mood disturbances in Ad will enable clinicians to set up appropriate
management of their patients. As published longitudinal studies are few, further works should be carried out to
improve knowledge of the pattern and course of depression and depressive symptoms in Ad.
