A study of psychological distress in caregivers of Parkinson's Disease patients

The aim of this PhD was to extend current research on caregiving by investigating outcomes for a large group of caregivers who have been relatively neglected in the caregiving literature. The focus of the research was to identify predictors of psychological distress in caregivers of Parkinson’s disease (PD) patients using a longitudinal design and quantitative and qualitative data. In chapter one, Parkinson’s disease is described in sufficient detail to illustrate the demands of PD caregivers. In chapter two, the caregiving literature is reviewed. The major factors in the prediction of caregiver distress are covered and various hypotheses are made with respect to Parkinson’s disease caregiving. It was hypothesised that the much greater physical demands placed on those who give care to PD patients would mean that the predictors of negative outcomes may not be the same as the predictors of distress in other caregiving situations. In chapter three, current models of caregiving are presented and evaluated. As caregiving can be perceived as being a job, theories from the organisational stress literature as well as the caregiving literature were used to conceptualise PD caregiving in a simple model. From the organisational literature, it was hypothesised that the interaction of job demand and discretion would predict distress, and that uncertainty, or lack of knowledge, would be a predictor of distress. A methods section follows in which the choice of measures is discussed. In this research, caregiver distress was not seen as a global concept, but rather it was reduced to six qualitatively distinct components - burden from impact on relationship, burden from impact on social life, emotional burden, depression, poor psychological health and low life satisfaction. Patients and caregivers were tested on two occasions. The tests and interviews took place approximately fourteen months apart. 83 patients and caregivers took part in phase I; 56 patients and caregivers took part in phase II. The main cause of atrophy was death. Phase I results are presented in chapter four, and phase II results are presented in chapter five. The main findings were (i) that it was correct to reduce caregiver distress for the predictor variables accounting for the maximum variance were different for each aspect of distress, (ii) patient variables - particularly physical demand and cognitive demand - were found to be important predictors of PD caregiver distress, (iii) caregiver personality and coping style had a major influence on caregiving outcomes, (iv) although there was a measurable progression of PD from phase I to phase II, there was no increase in distress in the same period, (v) there were moderator variables that did not directly predict distress but were nevertheless important to a model of PD caregiving, (vi) contrary to the hypothesis, the more that caregivers knew about PD, the greater their distress. It was suggested that this is a result of having to learn about the illness situation by experience. Qualitative data is presented in chapter six to describe carers’ experiences of Parkinson’s disease. Summary statistics and selected case studies are used to illustrate important themes, such as onset, personality change and job demand. The results are discussed in chapter seven and it is concluded that there are predictors of distress that hold across caregiving situations. These tend to be caregiver variables such as personality and coping style. But there are also predictors of distress that are specific to Parkinson’s disease, such as job demand which, unlike in most other caregiving situations, was the biggest predictor of two aspects of distress. It was concluded that a general model of caregiving is not appropriate, and a revised simple model of Parkinson’s disease caregiving is presented