Cohort profile: the COVID-19 Coping Study, a longitudinal mixed-methods study of middle-aged and older adults' mental health and well-being during the COVID-19 pandemic in the USA.

Purpose: The COVID-19 pandemic, beginning in early 2020, has resulted in massive social, economic, political and public health upheaval around the world. We established a national longitudinal cohort study, the COVID-19 Coping Study, to investigate the effects of pandemic-related stressors and changes in life circumstances on mental health and well-being among middle-aged and older adults in the USA.

Participants: From 2 April to 31 May 2020, 6938 adults aged ≥55 years were recruited from all 50 US states, the District of Columbia and Puerto Rico using online, multi-frame non-probability-based sampling.

Findings To Date: Mean age of the baseline sample was 67.3 years (SD: 7.9 years) and 64% were women. Two in three adults reported leaving home only for essential purposes in the past week (population-weighted proportion: 69%; 95% CI: 68% to 71%). Nearly one in five workers aged 55-64 years was placed on a leave of absence or furloughed since the start of the pandemic (17%; 95% CI: 14% to 20%), compared with one in three workers aged ≥75 years (31%; 95% CI: 21% to 44%). Nearly one-third of adults screened positive for each of depression (32%; 95% CI: 30% to 34%), anxiety (29%; 28% to 31%) and loneliness (29%; 95% CI: 27% to 31%), with decreasing prevalence of each with increasing age.

Future Plans: Monthly and annual follow-ups of the COVID-19 Coping Study cohort will assess longitudinal changes to mental health, cognitive health and well-being in relation to social, behavioural, economic and other COVID-19-related changes to life circumstances. Quantitative and in-depth qualitative interview data will be collected through online questionnaires and telephone interviews. Cohort data will be archived for public use.