Measuring General Expectations of Advanced Stage Treatment Outcomes in Parkinson’s Disease

Article type: Research Article

Authors: Loftus, Andrea M.^{a; *} | Nielsen, Chloe^a | Corti, Emily J.^a | Starkstein, Sergio^b | Gasson, Natalie^a | Egan, Sarah J.^{a; c}

Affiliations: [a] Discipline of Psychology, School of Population Health, Curtin University, Perth, WA, Australia | [b] Faculty of Health and Medical Sciences, University of Western Australia, UWA Health Campus (QEII), Monash Avenue, Nedlands, WA, Australia | [c] enAble Institute, Faculty of Health Sciences, Curtin University, Perth, WA, Australia

Correspondence: [*] Correspondence to: Andrea Loftus, PhD, Discipline of Psychology, School of Population Health, Curtin University, GPO Box U1987, Perth, WA, 6847, Australia. Tel.: +61 8 9266 5120; E-mail: andrea.loftus@curtin.edu.au.

Abstract: Background:Recent research suggests that a significant number of those who receive advanced treatments for Parkinson’s disease (PD) do not report improvements for some symptoms, which may relate to their pre-treatment expectations. It is important that expectations of treatment are measured and discussed prior to advanced treatment. Objective:The primary aim of this study was to develop a measure of treatment expectations of two advanced-stage treatments in PD, deep brain stimulation (DBS), and Levodopa/Carbidopa Intestinal Gel (LCIG). A secondary aim was to explore potential predictors of treatment expectations. Methods:The questionnaire-based measure was developed by researchers in conjunction with a highly experienced clinician, and evaluated treatment expectations in 189 people aged 46–91 years (M = 71.35, SD = 8.73; 61% male) with idiopathic PD. Results:The overall measure demonstrated excellent internal consistency (α= 0.96). Exploratory factor analysis suggested the scale was unidimensional for both DBS and LCIG. Participant expectations of the two treatments differed significantly, with expectations being higher for DBS. Perceived symptom severity was the strongest predictor of treatment expectations. Conclusion:This scale has potential to inform clinicians about client expectations prior to advanced stage therapy for PD, with a view to the management of these expectations. Further evaluation of the scale is required across different treatment contexts.

Keywords: Parkinson’s disease, treatment expectations, deep brain stimulation, Levodopa/carbidopa intestinal gel, quality of life, psychological

DOI: 10.3233/JPD-212777

Journal: Journal of Parkinson's Disease, vol. 11, no. 4, pp. 2017-2026, 2021