The longitudinal effect of COVID-19 infections and lockdown on mental health and the protective effect of neighbourhood social relations

RATIONALE: The effect of COVID-19 lockdowns on mental health is a major concern worldwide. Measuring the impacts, however, is difficult because of a lack of data that tracks and compares outcomes and potential protective social factors before and during lockdowns. OBJECTIVE: We aim to quantify the impact of a second lockdown in 2020 in the Australian city of Melbourne on levels of depression, anxiety, and loneliness, and analyse whether social relations in the neighbourhood may buffer against the worst effects of lockdown. METHODS: We draw on quasi-experimental data from a nationally-representative longitudinal survey conducted in Australia. We use a difference-in-difference approach with a number of control variables to estimate changes in mental health among respondents in Melbourne following the imposition of the lockdown. A measure of perceived neighbourhood social relations is included as an explanatory variable to analyse potential protective effects. RESULTS: Lockdown is estimated to have increased depressive symptoms by approximately 23% and feelings of loneliness by 4%. No effect on anxiety was detected. Levels of neighbourhood social relations were strongly negatively associated with mental health symptoms. A significant interaction between lockdown and neighbourhood social relations suggests that lockdown increased depressive symptoms by 21% for people with average perceived neighbourhood relations, compared with a 9.7% increase for people whose perceived relations is one standard deviation greater than average. CONCLUSION: The results add to evidence of the harsh impacts of the COVID-19 pandemic and associated lockdowns on mental health. Importantly, neighbourhood social relations and social cohesion more broadly may be an important source of social support in response to lockdowns. These findings provide important insights for researchers and policy-makers in how to understand and respond to the mental health impacts of COVID-19.