What contributes to quality of life in Parkinson’s disease: a re-evaluation

Twenty years ago, we published a paper examining which of the clinical features of Parkinson’s disease (PD) were most closely associated with patients’ self-reported health-related quality of life (HR-QoL).1 In the early 1990s, the focus of clinical management and treatment trials in PD had been the development of better management options for the motor features and complications of therapy, such as motor fluctuations and dyskinesias. The key target in clinical trials was improvement on the primary outcome measure, the Unified Parkinson’s Disease Rating Scale (UPDRS).2 However, clinical assessment, and in particular clinical trials, almost entirely relied on clinicians’ judgement of severity of disease and its complications. This was a reflection of lack of availability of robust measures to capture patients’ own view, and probably also a different attitude in medicine and society in general, which placed greater emphasis on clinician judgement than on patients’ evaluation. However, in the late 1990s, this had started changing and the development of standardised scales to assess how patients evaluate their own health problems, so-called HR-QoL measures, had recently enabled standardised quantitative assessment of patients’ views. HR-QoL scales made it possible to assess impact on patients’ lives, independent from clinicians' assessments, and to incorporate other aspects of HR-QoL, such as the emotional and social impact of the disease. A HR-QoL specifically for patients with PD had been developed through careful analysis of interviews and validation in patients with PD.3 This allowed assessment of the impact of PD on patients from more than a physical, objective point of view; it also provided the opportunity to assess which aspects of the features of PD have the greatest impact from patients’ perspective. However, no such studies had been published to answer this question. What contributes to Quality of Life in Parkinson’s disease - a revaluation …