Retention among alcohol-related liver disease patients in clinical trials: A systematic review and meta-analysis of interventional retention rates

BACKGROUNDAlcohol-related liver disease (ARLD) is the leading cause of cirrhosis and liver-related mortality in Europe, but few interventional clinical trials have been completed in this patient group.Such patients can experience challenges accessing and engaging with their treatment.High levels of retention in clinical trials enable more efficient trial design and ensure that the outcomes can be fully assessed as intended.However, it is not known how well patients with ARLD with recent or ongoing alcohol use engage with clinical trials. AIMTo quantify retention rates of ARLD patients recruited to interventional clinical trials at 1 month, 3 months, 6 months and 12 months after recruitment. METHODSAccording to our published review protocol (https://osf.io/5kuge/)we conducted systematic searches of MEDLINE, EMBASE, Web of Science, and Scopus.We included interventional clinical trials, published 2008 onwards in people with ARLD [including alcohol-related hepatitis (AH)].We excluded studies where patients had been abstinent from alcohol for more than 6 months.Data were extracted on study design, population and retention rates and a risk of bias assessment was made.Two-step meta-analysis was conducted to generate a random effects model. RESULTSOf 3072 identified studies, 68 were eligible for inclusion: 44 in AH and 24 in alcoholrelated cirrhosis (ARC).Studies were heterogenous in design, intervention, and outcome.Median study duration was 90 days.The primary outcome was mortality in 30 and 3 of 4 / 48 the AH and ARC trials, respectively.Overall retention rates at 1 month, 3 months, and 6 months were 88% [95% confidence interval (CI): 84%-92%], 70% (95%CI: 63%-76%), and 58% (95%CI: 50%-65%) respectively.Only six trials reported retention at 12 months, at 61% (95%CI: 43%-77%).In the ARC trials (n = 9), retention (excluding mortality) was 85% (95%CI: 69%-96%; I 2 = 92%) vs 97% (95%CI: 94%-99%; I 2 = 91%) in the AH trials (n = 38), at 3 months. CONCLUSIONMost trials focus on AH with mortality outcomes and short-term retention.There are fewer trials on ARC, which has low retention at 3 months.Engagement strategies are needed to ensure reliable results.