Patient and Caregiver Experiences of Participating in Parkinson's Disease Clinical Trials: A Systematic Review of Qualitative Studies.

BACKGROUND: Older people experience multiple barriers to enrolment in clinical trials. Caregivers play an important role in supporting patients with Parkinson's disease. Understanding the experiences of patients and caregivers who participate in trials is important to inform the design of future studies and identify problems with recruitment and retention. OBJECTIVE: To systematically review and synthesize qualitative studies exploring the experiences of participating in clinical trials from the perspectives of patients with Parkinson's disease and their caregivers. METHODS: Two reviewers independently searched the following databases: MEDLINE, Embase, PsycInfo, Cochrane, and CINAHL. The reference lists of all selected papers were screened for additional studies. Articles meeting predefined eligibility criteria were included in the synthesis. Methodological quality of each study was assessed using the Critical Appraisal Skills Programme (CASP) Qualitative Checklist. Included study findings were synthesized using the principles of thematic analysis. RESULTS: Eleven studies were included. Five key themes were identified: positive experiences of participating in research, assessment completion, motivators, enablers, and barriers. Positive experiences of participating in studies were linked to social interaction with other patients, building trust with the researchers, and expertise of the research team. CONCLUSIONS: This review supports literature highlighting the important role of caregivers in supporting patients with Parkinson's disease. Future studies are needed to further examine their perspectives on participating in research.

Safety and Tolerability of Natural and Synthetic Cannabinoids in Older Adults: A Systematic Review and Meta-Analysis of Open-Label Trials and Observational Studies.

BACKGROUND AND OBJECTIVE: Although cannabinoid-based medications are increasingly used by older adults, their safety and tolerability in this age group remain unclear. The purpose of this systematic review was to examine the safety and tolerability of cannabinoid-based medications by conducting a meta-analysis of open-label observational studies of cannabinoid-based medications for all indications in individuals with a mean age of ≥50 years. METHODS: A systematic search was conducted on PubMed, PsycINFO, MEDLINE, EMBASE and CINHAL. Study quality was assessed using an adapted version of the Grading of Recommendations Assessment, Development and Evaluation criteria and Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines were followed. We included studies that (a) were published from 1990 onwards; (b) included older adults (mean age ≥50 years); and (c) provided data on the safety and tolerability of medical cannabinoids. Data were pooled using a random-effects approach. Risk of adverse events, serious adverse events and withdrawals was computed as the incidence rate (IR). Separate analyses were conducted by the cannabinoid-based medication used, for delta-9-tetrahydrocannabinol (THC), cannabidiol (CBD) and a combination of THC and CBD (THC:CBD). RESULTS: Thirty-eight studies were identified (THC = 23; CBD = 6; THC:CBD = 9; N = 2341, mean age: 63.19 ± 8.08 years, men: 53.86%). THC had a very low incidence of all-cause and treatment-related adverse events (IR: 122.18, 95% confidence interval [CI] 38.23-253.56; IR: 84.76, 95% CI 0.13-326.01, respectively) and negligible serious adverse events (IR = 0). Similar IRs for CBD (all cause, IR: 111.91, 95% CI 1.24-495.93; treatment related, IR: 1.76, 95% CI 4.63-23.05) and no serious adverse events (IR = 0). CBD was not associated with a risk of treatment-related withdrawals. THC had a low risk of all-cause and treatment-related withdrawals (IR: 25.18, 95% CI 12.35-42.52; IR: 7.83, 95% CI 3.26-14.38, respectively). The THC:CBD treatment had a low risk of all-cause and treatment-related adverse events (IR: 100.72, 95% CI 0.25-383.00; IR: 55.38, 95% CI 8.61-142.80, respectively), but reported a risk of all-cause and treatment-related serious adverse events (IR: 21.32, 95% CI 0.18-93.26; IR: 3.71, 95% CI 0.21-11.56, respectively), and all-cause and treatment-related withdrawals (IR: 78.63, 95% CI 17.43-183.90; IR: 34.31, 95% CI 6.09-85.52, respectively). Significant heterogeneity (I2 >55%) was present in most analyses. CONCLUSIONS: Although cannabinoid-based medications were generally safe and acceptable to adults aged over 50 years, these estimates are limited by the lack of a control condition and considerable heterogeneity. Nevertheless, they complement and are consistent with comparable evidence from randomised controlled trials.

Safety and tolerability of natural and synthetic cannabinoids in adults aged over 50 years: A systematic review and meta-analysis.

BACKGROUND: Cannabinoid-based medicines (CBMs) are being used widely in the elderly. However, their safety and tolerability in older adults remains unclear. We aimed to conduct a systematic review and meta-analysis of safety and tolerability of CBMs in adults of age ≥50 years. METHODS AND FINDINGS: A systematic search was performed using MEDLINE, PubMed, EMBASE, CINAHL PsychInfo, Cochrane Library, and ClinicalTrials.gov (1 January 1990 to 3 October 2020). Randomised clinical trials (RCTs) of CBMs in those with mean age of ≥50 years for all indications, evaluating the safety/tolerability of CBMs where adverse events have been quantified, were included. Study quality was assessed using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) criteria and Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were followed. Two reviewers conducted all review stages independently. Where possible, data were pooled using random-effects meta-analysis. Effect sizes were calculated as incident rate ratio (IRR) for outcome data such as adverse events (AEs), serious AEs (SAEs), and death and risk ratio (RR) for withdrawal from study and reported separately for studies using tetrahydrocannabinol (THC), THC:cannabidiol (CBD) combination, and CBD. A total of 46 RCTs were identified as suitable for inclusion of which 31 (67%) were conducted in the United Kingdom and Europe. There were 6,216 patients (mean age 58.6 ± 7.5 years; 51% male) included in the analysis, with 3,469 receiving CBMs. Compared with controls, delta-9-tetrahydrocannabinol (THC)-containing CBMs significantly increased the incidence of all-cause and treatment-related AEs: THC alone (IRR: 1.42 [95% CI, 1.12 to 1.78]) and (IRR: 1.60 [95% CI, 1.26 to 2.04]); THC:CBD combination (IRR: 1.58 [95% CI,1.26 to 1.98]) and (IRR: 1.70 [95% CI,1.24 to 2.33]), respectively. IRRs of SAEs and deaths were not significantly greater under CBMs containing THC with or without CBD. THC:CBD combination (RR: 1.40 [95% CI, 1.08 to 1.80]) but not THC alone (RR: 1.18 [95% CI, 0.89 to 1.57]) significantly increased risk of AE-related withdrawals. CBD alone did not increase the incidence of all-cause AEs (IRR: 1.02 [95% CI, 0.90 to 1.16]) or other outcomes as per qualitative synthesis. AE-related withdrawals were significantly associated with THC dose in THC only [QM (df = 1) = 4.696, p = 0.03] and THC:CBD combination treatment ([QM (df = 1) = 4.554, p = 0.033]. THC-containing CBMs significantly increased incidence of dry mouth, dizziness/light-headedness, and somnolence/drowsiness. Study limitations include inability to fully exclude data from those <50 years of age in our primary analyses as well as limitations related to weaknesses in the included trials particularly incomplete reporting of outcomes and heterogeneity in included studies. CONCLUSIONS: This pooled analysis, using data from RCTs with mean participant age ≥50 years, suggests that although THC-containing CBMs are associated with side effects, CBMs in general are safe and acceptable in older adults. However, THC:CBD combinations may be less acceptable in the dose ranges used and their tolerability may be different in adults over 65 or 75 years of age.

A Preliminary Investigation of the Views of People With Parkinson's (With and Without Psychosis) and Caregivers on Participating in Clinical Trials During the Covid-19 Pandemic: An Online Survey.

Background: The coronavirus pandemic is having a profound impact on non-COVID-19 related research, including the delivery of clinical trials for patients with Parkinson's disease. Objectives: A preliminary investigation to explore the views of Parkinson's disease (PD) patients, with and without experience of psychosis symptoms, and carers on the resumption of clinical research and adaptations to trials in light of COVID-19. Methods: An anonymous self-administered online survey was completed by 30 PD patients and six family members/carers via the Parkinson's UK Research Support Network to explore current perceptions on taking part in PD research and how a planned clinical trial for psychosis in PD may be adapted so participants feel safe. Results: Ninety-one percent of respondents were enthusiastic about the continuation of non-COVID-19 related research as long as certain safety measures were in place. Ninety-four percent stated that they would be happy to complete assessments virtually. However, they noted that care should be taken to ensure that this does not exclude participants, particularly those with more advanced PD who may require assistance using portable electronic devices. Regular and supportive communication from the research team was also seen as important for maintaining the psychological well-being of participants while taking part in the trial. Conclusions: In the era of COVID-19 pandemic, standard approaches will have to be modified and rapid adoption of virtual assessments will be critical for the continuation of clinical research. It is important that alongside the traditional methods, new tools are developed, and older ones validated for virtual assessments, to allow safe and comprehensive assessments vital for ongoing research in people with Parkinson's.