Sociodemographic, mental health, and physical health factors associated with participation within re-contactable mental health cohorts: an investigation of the GLAD Study (preprint)

Background: The Genetic Links to Anxiety and Depression (GLAD) Study is a large cohort of individuals with lifetime anxiety and/or depression, designed to facilitate re-contact of participants for mental health research. At the start of the pandemic, participants from three cohorts, including the GLAD Study, were invited to join the COVID-19 Psychiatry and Neurological Genetics (COPING) study to monitor mental and neurological health. However, previous research suggests that participation in longitudinal studies follows a systematic, rather than random, process, which can ultimately bias results. Therefore, this study assessed participation biases following the re-contact of GLAD Study participants. Methods: In April 2020, all current GLAD Study participants (N = 36,770) were invited to the COPING study. Using logistic regression, we investigated whether sociodemographic, mental, and physical health characteristics were associated with participation in the COPING baseline survey. Subsequently, we used a zero-inflated negative binomial regression examined whether these factors were related to participation in the COPING follow-up surveys. Results: For aim one, older age, female gender identity, non-binary or prefer to self-define gender identity, having one or more physical health disorders, and providing a saliva kit for the GLAD Study were associated with an increased odds of completing the COPING baseline survey. In contrast, lower educational attainment, Asian or Asian British ethnic identity, Black or Black British ethnic identity, higher alcohol consumption at the GLAD sign-up survey and current or ex-smoking were associated with a reduced odds. For aim 2, older age, female gender, and saliva kit provision were associated with greater COPING follow-up survey completion. On the other hand, lower educational attainment, ex-smoking, higher alcohol consumption at the GLAD Study sign-up, and self-reported attention deficit hyperactivity disorder had negative relationships. Conclusions: Participation biases surrounding sociodemographic and physical health characteristics were particularly evident when re-contacting the GLAD Study volunteers. Future researchers re-contacting participants from existing cohorts/BioResources should be mindful of participation bias and how it may affect results obtained from analyses.

The Eating Disorders Genetics Initiative (EDGI) United Kingdom (preprint)

Objective The Eating Disorders Genetics Initiative United Kingdom (EDGI UK), part of the National Institute for Health and Care Research (NIHR) Mental Health BioResource, aims to deepen our understanding of the environmental and genetic aetiology of eating disorders. EDGI UK launched in February 2020 and is partnered with the UK eating disorders charity, Beat. There are multiple EDGI branches worldwide. Method EDGI UK recruits via media and clinical services. Anyone living in England, at least 16 years old, with a lifetime probable or clinical eating disorder is eligible to sign up online: edgiuk.org . Participants complete online questionnaires, donate a saliva sample for genetic analysis, and consent to medical record linkage and recontact for future studies. Results As of September 2022, EDGI UK has recruited 8,397 survey participants: 98% female, 93% white, 97.7% cisgender, 67% heterosexual, and 52% have a university degree. Half (51.7%) of participants have returned their saliva kit. The most common diagnoses are anorexia nervosa (42.7%), atypical anorexia nervosa (31.4%), bulimia nervosa (33.2%), binge-eating disorder (14.6%), and purging disorder (33.5%). Conclusion EDGI UK is the largest UK eating disorders study but needs to increase its diversity, and efforts are underway to do so. It also offers a unique opportunity to accelerate eating disorder research, and collaboration between researchers and participants with lived experience, with unparalleled sample size.

Risk and protective factors for new onset binge eating, low weight, and self-harm symptoms in over 25,000 individuals in the UK during the COVID-19 pandemic (preprint)

Objective: The disruption caused by the COVID-19 pandemic has been associated with poor mental health, including increases in eating disorder and self-harm symptoms. We investigated risk and protective factors for new onset of these symptoms during the pandemic. Method: Data were from the COVID-19 Psychiatry and Neurological Genetics study and the Repeated Assessment of Mental health in Pandemics Study (n = 45,058). Exposures were socio-demographic characteristics, lifetime psychiatric disorder, and COVID-related variables, including SARS-CoV-2 infection/illness with COVID-19. We identified four sub-samples of participants without pre-pandemic experience of our outcomes: binge eating (n = 18,172), low weight (n = 19,148), suicidal and/or self-harm ideation (n = 12,650), and self-harm (n = 20,266). Participants reported on our outcomes at frequent intervals (fortnightly to monthly). We fitted four logistic regression models to identify factors associated with new onset of our outcomes. Results: Within each subsample, new onset was reported by: 16.9% for binge eating, 8.9% for low weight, 26.6% for suicidal and/or self-harm ideation, and 3.3.% for self-harm. Shared risk factors included having a lifetime psychiatric disorder, not being in paid employment, and higher pandemic worry scores. Conversely, infection with SARS-CoV-2/illness with COVID-19 was linked to lower odds of all outcomes. Other factors were associated with one outcome, such as pandemic-related loneliness with suicidal and/or self-harm ideation. Discussion: Overall, we detected shared risk factors that may drive the comorbidity between eating disorders and self-harm. Subgroups of individuals with these risk factors may require more frequent monitoring during future pandemics.