In this thesis, longitudinal analyses have been performed on the PROPARK-Cohort, a hospital-based cohort of 421 patients followed for a period of five years. The main focus of this thesis was... Show moreIn this thesis, longitudinal analyses have been performed on the PROPARK-Cohort, a hospital-based cohort of 421 patients followed for a period of five years. The main focus of this thesis was to determine which predictors and associated factors contributed to the development of certain non-motor symptoms in Parkinson’s disease (PD). Strengths of our cohort study include the length of the follow-up period, broad clinical characterization, limited loss-to-follow-up and the large cohort size. The following non-motor symptoms have been addressed in this thesis: psychosis (hallucinations), dementia, excessive daytime sleepiness (EDS), insomnia, depression and anxiety. We found that while certain non-motor symptoms are inherent components of PD that increase in severity as the disease progresses, others symptoms such as excessive daytime sleepiness are inarguably caused by antiparkinsonian medication. For the future, we hope to see more longitudinal data on the disease progression in PD from large cohorts. Knowledge from longitudinal studies does not only contribute to more insight in the underlying pathobiology of PD, but it could also help the caregiver to monitor patients with particular risk factors more closely and adjust treatment if necessary. Show less
This thesis investigates different aspects of apathy - as a distinct clinical syndrome assessed with the Apathy Scale- in older persons with and without concurrent depression. In Chapter 2,... Show moreThis thesis investigates different aspects of apathy - as a distinct clinical syndrome assessed with the Apathy Scale- in older persons with and without concurrent depression. In Chapter 2, clinically relevant subtypes of apathy according to the Apathy Scale in older persons from the PROMODE study are examined, using data-driven Latent Class Analysis (LCA). Further, specific characteristics across the classes identified by LCA are investigated. Then, in Chapter 3, cross-sectionally the prevalence, severity and clinical profile of apathy in depressed and non-depressed older persons, in relation to various possible determinants is described. Chapter 4 examines which characteristics predict, over a 2-year period, the incidence and course of apathy in at baseline depressed older persons from the NESDO study. Chapter 5, using data of the NESDO and NESDA, investigates the presence of apathy in late-life compared to early-life depression, and various determinants of clinically relevant apathy in older compared to younger depressed persons. In Chapter 6 the association of the presence of apathy among community-dwelling older persons from the PROMODE study and a diminished quality of life is examined. All results are placed a current perspective in Chapter 7 that also discusses clinical implications, and makes some recommendations for future research. Show less
The overriding aim of my thesis was to study the relationship between blood pressure (BP) and cognitive and psychological functioning in older persons. Observational studies indicate that lower BP... Show moreThe overriding aim of my thesis was to study the relationship between blood pressure (BP) and cognitive and psychological functioning in older persons. Observational studies indicate that lower BP increases risk for cognitive decline in older persons. Older persons are at risk for impaired cerebral autoregulation, and lowering their BP may compromise cerebral blood flow and cognitive function. Contradictory to our hypothesis, the Discontinuation of Antihypertensive Treatment in Elderly people (DANTE) Study Leiden, a community-based randomized clinical trial in older persons (aged ≥75 years) with mild cognitive deficits, did not show that discontinuation of antihypertensive treatment improves cognitive functioning. The lack of the effect of this trial may be due to the unintentional inclusion of persons with a relatively intact cerebral autoregulation. Furthermore, we demonstrated that older persons with mild cognitive deficits and with orthostatic hypotension, who discontinued all their antihypertensive medication had an increased probability of being free from orthostatic hypotension 4 months later, compared to persons who continued their medication. Finally, in the DANTE MRI sub study, the relationship between BP and both conventional features of small vessel disease (SVD) and microstructural damage was explored, as well as the relation between microstructural damage and cognitive and psychological dysfunction. Show less
