Neuroanatomical and Prognostic Associations of Depression in Parkinson's Disease

This is a large-scale prospective cohort study on depression in patients with Parkinson’s disease (PD). Researchers have used the vast cohort data from the UK Biobank to investigate the temporal association between depression and the onset of PD, the relationship between depression and brain region structure in PD patients, and the impact of depression on cognitive impairment and survival in PD patients.

Background Introduction: Depression is reported as a risk factor, prodromal symptom, and subsequent complication of PD. However, the exact relationship between the timing of depression and the onset of PD, as well as the impact of depression on the prognosis of PD patients, have not been fully studied.

Research Source:
This study was written by James B. Badenoch and others. The authors are from the Queen Mary University of London Centre for Preventive Neurology, the Institute of Psychiatry and Neuroscience at King’s College, the Clinical Medical College of Cambridge University, and other institutions. The study was published in the Journal of Neurology, Neurosurgery and Psychiatry in 2024.

Research Process: a) The study involved 434,023 participants in the UK Biobank, with an average follow-up of 14.1 years. Multivariate regression models were used to analyze the association between depression and the risk of PD onset; flexible parametric models were used to assess the relationship between the diagnosis time of depression and the onset time of PD; multivariate linear regression analysis was used to analyze the correlation between the severity of depression in PD patients and the gray matter volume of brain regions. b) Main results: Of 2,632 PD patients, 20.5% had been diagnosed with depression. Diagnosis of depression was associated with an increased subsequent risk of PD onset (risk ratio 1.53); the prevalence of depression started to increase 10 years before the diagnosis of PD and continued to increase. The severity of depression was associated with a decrease in the gray matter volume in subcortical structures such as the hippocampus and amygdala, as well as certain cortical regions. c) In PD patients, depression in the early stages of PD diagnosis was associated with an increased risk of subsequent dementia onset (risk ratio 1.47) and an increased all-cause mortality risk (risk ratio 1.30). d) Research Highlights: The study clarified the temporal pattern of depression before and after the onset of PD, revealed the association between depression and brain structure damage in PD patients, and found that depression might be a marker of poor prognosis in PD patients. e) Research Value: This study provides large-sample prospective evidence for the clinical significance of depression in PD patients, helping to better assess the cognitive function and prognosis of these individuals.

This large-scale prospective study shows that the occurrence of depression is closely associated with the onset of PD and is accompanied by a reduction in gray matter volume in both the cortical and subcortical brain regions of patients. Depression prior to the diagnosis of PD may herald an increased risk of dementia and mortality, which is of clinical significance for stratified management and individualized prognosis evaluation in PD patients.