Parkinson disease and down in the dumps

Abstract

Depression is a common problem in Parkinson disease (PD), occurring in approximately 50% of patients throughout the disease course.1 It can be distressing to both patients and their families and results in both increased functional disability2 and cognitive impairment.3 It is unclear whether depression in PD is associated with neuroanatomic or neurochemical changes in the brain, although hippocampal atrophy can occur in depression, especially with untreated major depression.4 Treatment for depression currently assumes neurochemical imbalance of noradrenergic and serotonergic systems. However, future approaches to treatment may need to take into account any associated neuronal loss. Epidemiologic studies have reported that depression may precede the onset of PD symptoms,5 and therefore a neuroanatomic signature of depression in PD could be a useful biomarker to predict the development of PD in depressed patients. A further complexity is whether depression preceding the onset of PD has the same neuroanatomic correlates as depression occurring after the onset of PD. The study by Kostic et al.6 appearing in this issue …