An investigation of factors affecting changes in health behaviours during the COVID-19 pandemic in a UK population-based cohort study.

OBJECTIVES: The COVID-19 pandemic has led to changes in behaviours, which may have different health effects in population subgroups. We investigated whether within-individual changes in health behaviours from before to during the pandemic differ by socio-economic deprivation, age or sex. STUDY DESIGN: Prospective cohort study. METHODS: Participants were recruited from the existing UK Fenland cohort study with measurements of health behaviours twice prepandemic (2005 to February 2020) and three times during the pandemic (July 2020 to April 2021). Health behaviours included daily servings of fruit and vegetables, units of alcohol consumed per week, smoking status, sleep duration and total and domain-specific physical activity energy expenditure. Sociodemographic information (English indices of multiple deprivation, education, occupation and ethnicity) and COVID-19 antibody status were also collected. Participants were grouped into three categories based on their English indices of multiple deprivation score: most, middle and least deprived. RESULTS: Participants were included if they had completed at least one measurement during the pandemic and one prepandemic (n = 3212). Fruit and vegetable consumption, total physical activity energy expenditure and smoking prevalence decreased during the pandemic compared with prepandemic, whereas average sleep duration increased and alcohol consumption did not change. Decreases in fruit and vegetable intake and physical activity energy expenditure were most pronounced in the most deprived group compared with the least deprived group and were greater in women than men. CONCLUSIONS: Socio-economic inequalities in health behaviours have worsened during the pandemic. As the country emerges from the COVID-19 pandemic, strategies to reduce health inequalities need to be put at the forefront of recovery plans.

Supporting Weight Management during COVID-19 (SWiM-C): A randomised controlled trial of an acceptance-based behavioural intervention to prevent weight gain during the pandemic

Introduction: The social distancing and isolation measures imposed during the COVID-19 pandemic mean that adults with overweight and obesity in the UK are at increased vulnerability to weight gain and the associated negative impacts on physical and mental wellbeing. There is growing evidence that interventions based on Acceptance and Commitment Therapy (ACT) are more effective for weight management compared with standard behavioural treatment. In collaboration with patient and public representatives and other stakeholders, we developed an ACT-based behavioural intervention to support adults with overweight and obesity to prevent weight gain during the COVID-19 pandemic (SWiM-C). This study evaluated whether SWiM-C reduced weight and achieved greater improvements in eating behaviour, physical activity and mental wellbeing compared with standard advice, over four months during the pandemic. Methods: We randomised adults (BMI≥25kg/m2) to the SWiM-C intervention or to a standard advice wait list control group. SWiM-C is an ACT-based guided self-help intervention consisting of weekly webbased sessions for 12 consecutive weeks, with two remote contacts (by telephone and email) from a trained non-specialist coach. The control group received standard advice from the European Association for the Study of Obesity (EASO) on diet, physical activity, and mental wellbeing during the COVID-19 pandemic. The planned sample size was 360 to give us 90% power to detect a 1kg difference between groups at the 5% level. Participants completed outcome assessments online at baseline and 4 months follow-up. The primary outcome was change in self-measured weight from baseline to four months;secondary outcomes included depression, anxiety, stress, psychological flexibility, eating behaviour (cognitive restraint, uncontrolled eating and emotional eating), physical activity, and health-related quality of life. Analysis was based on the intention-to-treat principle. We estimated baseline-adjusted differences between the study groups in change in weight (and secondary outcomes) from baseline to 4 months using linear regression models, also adjusting for randomisation stratifiers (sex, BMI group). Results: We recruited and randomised 388 participants (196 standard advice, 192 SWiM-C). 187 (97%) SWiM-C participants started the intervention, 167 (87%) completed the coach call, 161 (84%) were sent tailored coach emails, and 93 (48%) completed at least 8 sessions. Follow-up for the primary outcome was completed by 325 (84%) participants. Analysis of the effectiveness of SWiM-C is currently underway and will be completed before the conference. Conclusion: There is a need for user-friendly and remotely delivered weight management interventions to support adults with overweight and obesity during the COVID-19 pandemic. SWiM-C has demonstrated excellent uptake and engagement levels for a predominantly digital intervention, and we will report on the effectiveness of this approach. Findingswill inform the evidence base on digital interventions for weight management and can be used to inform existing services which are currently transitioning from face-to-face to online delivery.