Non-binary gender, vulnerable populations and mental health during the COVID-19 pandemic: Data from the COVID-19 MEntal health inTernational for the general population (COMET-G) study

Background: The COVID-19 pandemic has brought significant mental health challenges, particularly for vulnerable populations, including non-binary gender individuals. The COMET international study aimed to investigate specific risk factors for clinical depression or distress during the pandemic, also in these special populations. Methods: Chi-square tests were used for initial screening to select only those variables which would show an initial significance. Risk Ratios (RR) were calculated, and a Multiple Backward Stepwise Linear Regression Analysis (MBSLRA) was followed with those variables given significant results at screening and with the presence of distress or depression or the lack of both of them. Results: The most important risk factors for depression were female (RR = 1.59–5.49) and non-binary gender (RR = 1.56–7.41), unemployment (RR = 1.41–6.57), not working during lockdowns (RR = 1.43–5.79), bad general health (RR = 2.74–9.98), chronic somatic disorder (RR = 1.22–5.57), history of mental disorders (depression RR = 2.31–9.47; suicide attempt RR = 2.33–9.75; psychosis RR = 2.14–10.08; Bipolar disorder RR = 2.75–12.86), smoking status (RR = 1.15–5.31) and substance use (RR = 1.77–8.01). The risk factors for distress or depression that survived MBSLRA were younger age, being widowed, living alone, bad general health, being a carer, chronic somatic disorder, not working during lockdowns, being single, self-reported history of depression, bipolar disorder, self-harm, suicide attempts and of other mental disorders, smoking, alcohol, and substance use. Conclusions: Targeted preventive interventions are crucial to safeguard the mental health of vulnerable groups, emphasizing the importance of diverse samples in future research. Limitations: Online data collection may have resulted in the underrepresentation of certain population groups.