Introduction Several factors influence the effectiveness of labour reintegration after an episode of sick leave due to mental disorders (MD). When workers remain working more than 30 days after being back to work is known as sustained return-to-work (S-RTW). This study aims to analyse factors associated to the effectiveness of S-RTW after sickness absence due to MD.

Methods A longitudinal study was conducted in the city of São Paulo, Brazil, from 2014–2016 and included 204 workers requiring sickness social security benefit due to MD. In baseline, participants fill questionnaires about sociodemographic info, health risk behaviours, work characteristics, health conditions and social security history. They were followed for 365 days after the first day of sickness absence. Those who have returned to work within this period were interviewed about employer´s RTW process (n=128). A multiple logistic regression was performed to analyse the factors that contributed to the S-RTW.

Result The average time for return to work was approximately six months among the 63.0% who tried to resume their work activities. The effectiveness rate among those who tried to return was 74%. Factors associated to the S-RTW were: working for 5 or more years in the current job (HR 3.69; 95% CI: 1.13 to 12.02), high return-to-work self-efficacy at baseline (HR 0.25; 95% CI: 0.07 to 0.91) and was evaluated by a physician before RTW (HR 4.93; 95% CI: 1.48 to 16.43) – when adjusted by sex, job title, depressive symptoms and social security benefit type.

Discussion Workers psychological conditions, occupational aspects and employer´s RTW process are associated to the effectiveness of the workers reintegration to work. It is important to understand this process in order to encourage and to stimulate public and private intervention policies on tertiary prevention, focused in effective RTW after sick leave due to MD. Acknowledgment: CNPq for financial support (Grant n° 442051/2014–0).