Time to recurrence of mental health-related absence from work.

BACKGROUND It is unclear when occupational health providers should re-evaluate workers after mental health-related absences from work. AIMS To investigate the time to recurrence of mental health-related absences, stratified by International Classification of Diseases-Tenth Revision (ICD-10) diagnostic categories. METHODS A 10-year observational study of workers employed at a steel mill. Sickness absence data were retrieved from an occupational health register. Mental health-related absences were defined as absence due to emotional disturbance or mental and behavioural disorders. The first mental health-related absence since baseline was called the index episode. Recurrences were defined as mental health-related absences occurring >28 days after recovery from the index episode. The frequency of recurrent mental health-related absence was assessed by the recurrence density (RD) per 1000 person-years. The time to recurrent mental health-related absence was investigated by Kaplan-Meier survival analysis. RESULTS Of 15461 workers, 391 had recurrent mental health-related absences. RD was 30.5, 34.3, 29.9 and 37.7 per 1000 person-years after index episodes due to emotional disturbance, mood disorders, neurotic disorders and other psychiatric disorders, respectively. RDs did not differ across ICD-10 diagnostic categories. The median time to recurrent mental health-related absence was 15.2 months [95% confidence interval (CI) 12.6-17.7] and was shortest for mood disorders (5.2, 95% CI 1.4-8.9 months) and specific psychiatric disorders (5.3, 95% CI 1.0-13.1 months). CONCLUSIONS Based on this observational study, we suggest that occupational and primary health care providers consider reviewing the mental health status of workers 6 months after recovery from mental health-related absence.