Mitigating the psychological impacts of COVID-19 restrictions on older people: The UK Behavioural Activation in Social Isolation (BASIL+) COVID-19 Urgent Public Health (UPH) trial and living systematic review

Background Older adults were more likely to be socially isolated during the COVID-19 pandemic, with risk of depression and loneliness. Behavioural Activation (BA) could feasibly maintain mental health in the face of COVID isolation. Methods We undertook a multicentre randomised controlled trial [BASIL+ [ISRCTN63034289][1]] of BA to mitigate depression and loneliness among older people. BA was offered by telephone to intervention participants (n=218). Control participants received usual care, with existing COVID wellbeing resources (n=217). Findings Participants engaged with 5.2 (SD 2.9) of 8 remote BA sessions. Adjusted mean difference (AMD) for depression (PHQ-9) at 3 months [primary outcome] was -1.65 (95% CI -2.54 to -0.75, p<0.001). There was an effect for BA on emotional loneliness at 3 months (AMD -0.37, 95% CI -0.68 to -0.06, p=0.02), but not social loneliness (AMD -0.05, 95% CI -0.33 to 0.23, p=0.72). Other secondary outcomes at 3 months were anxiety (GAD-7: AMD -0.67, 95% CI -1.43 to 0.09, p=0.08) and quality of life (SF12 mental component: AMD 1.99, 95% CI 0.22 to 3.76, p=0.03; physical component: AMD - 0.50, 95% CI -2.14 to 1.10, p=0.53). BASIL+ trial results were incorporated into a living systematic review [PROSPERO CRD42021298788], and we found strong evidence of an impact of behavioural and/or cognitive strategies on depression [random effects pooled standardised mean difference -0.32, 95% CI -0.48 to -0.16, 10 studies, n=1,210 participants] and loneliness [random effects pooled standardised mean difference -0.44, 95%CI -0.64 to -0.24, 13 studies, n=1,421 participants] in the short-term (<6 months). Interpretation BA is an effective intervention that reduces depression and some aspects of loneliness in the short term. This adds to the range of strategies to improve population mental health, particularly among older adults with multiple long-term conditions. These results will be helpful to policy makers in preventing depression and loneliness beyond the pandemic. Funding NIHR RP-PG-0217-20006 ### Competing Interest Statement The authors have declared no competing interest. ### Clinical Trial ISRCTN63034289 ### Clinical Protocols ### Funding Statement This project was funded by the NIHR Programme Grants for Applied Research (PGfAR) programme (RP-PG-0217-20006). The scope of our pre-existing research into multimorbidity in older people was extended at the outset of the COVID-19 pandemic with the agreement of the funder to consider depression and loneliness in this vulnerable group. The NIHR PGfAR programme had no role in the writing of this manuscript or the decision to submit it for publication. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The BASIL+ trial received ethical approval from a Research Ethics Committee (The Old Chapel, Royal Standard Place, Nottingham, NG1 6FS, UK; +44 (0)207 104 8018; leedswest.rec@hra.nhs.uk) on 11/12/2021 (REC Ref: 20/YH/0347). The sponsor for BASIL+ was Tees, Esk and Wear Valleys NHS Foundation Trust. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes Anonymised data will be made available upon reasonable request, which must include a protocol and statistical analysis plan and not be in conflict with our prespecified publication plan, consistent with our data sharing policy (available on request from SG). The BASIL research collective is especially keen that the BASIL data contributes to prospective meta-analyses and individual patient data meta-analyses. Requests for data sharing will be considered by SG and the independent trial steering and data monitoring committee. [1]: /external-ref?link_type=ISRCTN&access_num=ISRCTN63034289