Depression, anxiety, and cognitive deficits in Parkinson’s Disease [MSc Dissertation].

Depression has been suggested to be a frequently co-occurring symptom in Parkinson’s disease (PD) and research evidence has associated the disorder with impaired performance on a number of cognitive tests, especially those indicating frontal lobe cognitive dysfunction. The current study explored the relationship between depression and anxiety in Parkinson’s disease and frontal lobe cognitive impairment. Twenty community-based participants with PD were compared with 20 participants, over the age of 60 years, without a diagnosis of Parkinson’s disease, matched for age, sex, educational level, and pre-morbid intelligence. The Hospital Anxiety and Depression Scale (HADS) was used to measure mood, and the FAS Verbal Fluency test, the Wisconsin Card Sorting Test, and a Stroop test were employed to measure frontal lobe cognitive functioning. The group with Parkinson’s disease was characterised by greater anxiety and depression, in addition to impaired Verbal Fluency performance, compared with the group without the disorder. Participants with PD and major depression as defined by the HADS exhibited greater general cognitive impairment as measured by the Mini-Mental State Examination (MMSE). Younger participants and those in whom the disease had been diagnosed at a younger age were more likely to suffer from anxiety. A number of participants with Parkinson’s disease exhibited co-morbid anxiety and depression. In addition, four of the research sample with Parkinson’s disease scored below the cut-off point on the MMSE indicative of cognitive impairment sufficient to suggest dementia. Implications for those living with Parkinson’s disease plus recommendations for future research are discussed.