Affective disorders in Parkinson's disease

Abstract

This article reviews the prevalence, phenomenology, main clinical correlates, potential mechanisms, and treatment modalities of depression in Parkinson's disease (PD). In cross-sectional samples of PD patients attending a neurology unit the prevalence of depression is about 40%, but prevalences may be lower in epidemiological samples. Both psychological and autonomic symptoms of depression are specific to the depressive syndrome of PD, except for the symptoms of anergia, motor retardation, and early morning awakening. Depression may start before the onset of motor symptoms, and most patients with PD may eventually develop depression at some point during their longitudinal evolution. Follow-up studies suggest that PD patients with major depression have a significantly faster decline in activities of daily living and cognitive functions, and a faster progression along the stages of the illness as compared to non-depressed PD patients. Finally, there are few controlled studies of antidepressants in PD, but tricyclic compounds demonstrated adequate efficacy and tolerability.