The Association Between Case Manager Interactions and Serious Mental Illness Following a Physical Workplace Injury or Illness: A Cross-Sectional Analysis of Workers' Compensation Claimants in Ontario.

Poor mental health is a common occurrence among workers recovering from a work-related injury or illness. The objective of this cross-sectional study was to estimate the association between adverse interactions with workers' compensation case managers and experiencing a serious mental illness 18-months following a workplace injury or illness. A cohort of 996 workers' compensation claimants in Ontario Canada were interviewed 18 months following a disabling work-related injury or illness. Perceptions of informational and interpersonal justice in case manager interactions were defined as the primary independent variables, and Kessler Psychological Distress (K6) scores greater than 12, indicative of a serious mental illness, was defined as the outcome. Multivariate modified Poisson models estimated the association between perceptions of adverse case manager interactions and a serious mental illness, following adjustment for sociodemographic and work characteristics and pre-injury mental health. The prevalence of serious mental illness at 18 months was 16.6%. Low perceptions of informational justice, reported by 14.4% of respondents, were associated with a 2.58 times higher risk of serious mental illness (95% CI 1.30-5.10). Moderate and low perceptions of interpersonal justice, reported by 44.1% and 9.2% of respondents respectively, were associated with a 2.01 and 3.57 times higher risk of serious mental illness (95% CI moderate: 1.18-3.44, 95% CI poor: 1.81-7.06). This study provides further support for the impact of poor interactions with claims case managers on mental health, highlighting the importance of open and fair communication with workers' compensation claimants in ensuring timely recovery and return-to-work.