ABSTRACT
BACKGROUND: Our aim was to investigate the mediating role of worsening sleep quality in the association of the incidence of physical inactivity, high TV-viewing, and high computer/tablet use with loneliness, sadness, and anxiety. METHODS: Data of 45,161 Brazilian adults from a nationwide behavior survey, conducted between April 24th and May 24th (2020), were used. Participants reported physical inactivity (PI; <150 min/week), high TV-viewing (TV; ≥4 h/day), and high computer/tablet use (PC; ≥4 h/day) before and during COVID-19 quarantine (exposures). For incidence indicators, we only considered participants without the risk behavior before quarantine. Changes in sleep quality during the quarantine period (maintained/got better or worsened) were treated as a mediator. Elevated frequencies of feelings of loneliness, sadness (feel sad, crestfallen, or depressed), and anxiety (feel worried, anxious, or nervous) during the pandemic period were the study outcomes. Analyses were adjusted for sex, age group, highest academic achievement, working status during quarantine, skin color, previous diagnosis of depression, and adherence to quarantine. Mediation models were created using the Karlson Holm Breen method. RESULTS: The incidence of PI, high TV, and high PC use were associated with loneliness, sadness, and anxiety feelings. Worsening sleep quality partly mediated the association of the incidence of PI, high TV, and high PC use with loneliness (PI:30.9%; TV:19.6%; PC: 30.5%), sadness (PI:29.8%; TV:29.3%; PC: 39.1%), and anxiety (PI:21.9%; TV:30.0%; PC:38.5%). CONCLUSION: The association of the incidence of physical inactivity and sedentary behaviors with mental health indicators is partly mediated by worsening sleep quality during the COVID-19 pandemic quarantine.