Recruitment and retention of participant and study partner dyads in two multinational Alzheimer’s disease registration trials
Year: 2021
Type: article
Abstract: BACKGROUND: Early study exit is detrimental to statistical power and increases the risk for bias in Alzheimer's disease clinical trials. Previous analyses in early phase academic trials demonstrated associations between rates of trial incompletion and participants' study partner type, with participants enrolling with non-spouse study partners being at greater risk. METHODS: We conducted secondary analyses of two multinational phase III trials of semagacestat, an oral gamma secretase inhibitor, for mild-to-moderate AD dementia. Cox's proportional hazards regression model was used to estimate the relationship between study partner type and the risk of early exit from the trial after adjustment for a priori identified potential confounding factors. Additionally, we used a random forest model to identify top predictors of dropout. RESULTS: Among participants with spousal, adult child, and other study partners, respectively, 35%, 38%, and 36% dropped out or died prior to protocol-defined study completion, respectively. In unadjusted models, the risk of trial incompletion differed by study partner type (unadjusted p value = 0.027 for test of differences by partner type), but in models adjusting for potential confounding factors, the differences were not statistically significant (p value = 0.928). In exploratory modeling, participant age was identified as the primary characteristic to explain the relationship between study partner type and the risk of failing to complete the trial. Participant age was also the strongest predictor of trial incompletion in the random forest model. CONCLUSIONS: After adjustment for age, no differences in the risk of incompletion were observed when comparing participants with different study partner types in these trials. Differences between our findings and the findings of previous studies may be explained by differences in trial phase, size, geographic regions, or the composition of academic and non-academic sites.
Source: Alzheimer s Research & Therapy
Institution: University of California, Irvine
Language: English
Topic: Ethics in Clinical Research
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $3,490
Awards: G2142974134, Institute for Clinical and Translational Science, Alzheimer's Disease Cooperative Study (ADCS), G4932597581, G6886011585, G731022846, Effects of Alzheimer's disease clinical trial study partners, G7857944114, Alzheimer's Disease Cooperative Study, G9000134521, Assessing the role of cerebrovascular brain injury and dysfunction in Alzheimer’s disease pathogenesis in the BEACoN Cohort, The Alzheimer's Disease Research Center at the University of California, Irvine
OpenAlex ID: W3112823611