Effects of biopsychosocial factors on the association between loneliness and mental health risks during the COVID-19 lockdown

Previous data suggest that loneliness is a hallmark of the mental health issues triggered by the SARS-CoV-2 pandemic. The purpose of the present study was to examine the impact of loneliness on mental health and behavioural outcomes, as well as the moderating and mediating effects of biopsychosocial variables on these relationships. The data were collected during France’s first national COVID-19 lockdown and included 556 participants (M(age) = 30.06 years, range = 18–87) who completed well-known validated measures assessing symptom-levels of anxiety, depression, and insomnia. They also indicated their level of worry about the COVID-19 crisis, and provided sociodemographic and health status data. Responses were submitted to hierarchical linear regression and mediation analyses. In terms of prevalence of loneliness, 18.9% of participants reported severe loneliness. High levels of loneliness were significantly associated with the three mental health and behavioural outcomes. The loneliness – anxiety relationship was moderated by employment and working arrangements. The loneliness – insomnia relationship was moderated by living conditions, history of medical or psychological problems, and COVID-19-related worry. Further findings supported the indirect effects of COVID-related worry on pathways from loneliness to the three mental health and behavioural health outcomes. The mediation models accounted for 28.9%, 33.7%, and 15.0% of the variance in anxiety, depression, and insomnia. The present evidence-based findings revealed that loneliness and worry were major contributing factors of mental health and behavioural concerns during the COVID-19 lockdown. They could inform treatment recommendations for tackling prolonged-self isolation and loneliness in specific vulnerable groups. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12144-021-02246-w.