Joauqim J. Ferreira

Background Although there is growing recognition of the relevancy of informal caregivers there is scarce information on the contributory factors of caregiver burden in Parkinson's Disease (PD). Objective To identify the main associated factors to caregivers’ burden in people caring for a person with PD. Methods We analyzed the data set from a multinational online survey the Parkinson's real‐world impact assesSMent (PRISM) focusing on medication use, comorbidities, health‐related quality of life, relationship changes and the use of healthcare and supportive care resources by people with PD and their carers. Structured questionnaires including the Parkinson's disease quality of life questionnaire (PDQ‐39), non‐motor symptoms questionnaire (NMSQuest) and the Questionnaire for impulsive‐compulsive disorder in Parkinson's disease (QUIP) were applied. Caregiver burden was assessed by the Zarit Burden Interview (ZBI). Results In a cohort of 245 dyads (patient and respective caregiver), caregivers reported a mild to moderate burden. Carers’ perception of PD impact in partnership, financial burden, hours of care, patient's age, hypersexuality and health‐related quality of life (HRQoL) were found to be significant contributory factors to caregiver burden. Taken together these variables explained 66.8% of the variance in the Interpretation of the ZBI total score. Conclusions Caring for a person with PD entails substantial burden, particularly when the caregiver perceives greater changes in partnership dynamics, dedicates more time to caregiving tasks, has financial burden, and when the patient is older, reports worst HRQoL and has sexual compulsive urges.

Background The impact of expectation of benefit on outcomes is well established in Parkinson's disease (PD). A reduction of a treatment effect due to a perceived placebo allocation (lessebo effect) in randomized controlled trials (RCTs) was documented for symptomatic treatments. Objectives To evaluate the lessebo effect in disease modification RCTs (DMT) in PD. Methods Subject‐level meta‐analyses of active treatment arms of DMT (n = 1149 subjects): FS‐1, FS‐TOO (probability of placebo allocation/ P (placebo) = 0.33) and DATATOP, PRECEPT, QE2 ( P (placebo) = 0.25). We tested the association between P (placebo) and time to dopaminergic treatment initiation using a marginal Cox proportional hazards model. Results The adjusted hazard ratio ( P (placebo) = 0.25 vs. 0.33) for initiation of dopaminergic treatment was 1.15 (95% CI: 0.92–1.43). Conclusions We did not observe the lessebo effect in DMT. The necessary use of a placebo (and no active comparator) is a limitation. The prospective measurement of expectation of benefit could help to evaluate the many impacts of placebo use. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.