Labour market participation and sick leave among patients diagnosed with myasthenia gravis in Denmark 1997–2011: a Danish nationwide cohort study

BACKGROUND: To examine labour market participation and long-term sick leave following a diagnosis with myasthenia gravis (MG) compared with the general Danish population and for specific subgroups of MG patients. METHODS: A nationwide matched cohort study from 1997 to 2011 using data from population-based medical and social registries. The study includes 330 MG patients aged 18 to 65 years old identified from hospital diagnoses and dispensed prescriptions, and twenty references from the Danish population matching each MG patient on age, gender, and profession. Main outcome measures are labour market participation (yes/no) and long-term sick leave ≥9 weeks (yes/no) with follow-up at 1- and 2 years after the time of MG diagnosis or match. Based on complete person-level information on all public transfer payments in Denmark, persons having no labour market participation are defined as individuals receiving social benefits for severely reduced workability, flexijob, and disability pension. RESULTS: MG is consistently associated with higher odds of having no labour market participation and long-term sick leave compared with the general Danish population (no labour market participation & ≥9 weeks sick leave at 2-year follow-up, adjusted OR (95% CI): 5.76 (4.13 to 8.04) & 8.60 (6.60 to 11.23)). Among MG patients, females and patients treated with both acetylcholinesterase inhibitors and immunosuppression have higher odds of lost labour market participation and long-term sick leave. CONCLUSIONS: This study suggests that MG patients have almost 6 times higher odds of no labour market participation and almost 9 times higher odds of long-term sick leave 2 years after diagnosis compared with the general Danish population. In particular female MG patients and patients treated with both acetylcholinesterase and immunosuppression have high odds of a negative labour market outcome. Future research should focus on predictors in workplace and labour market policy of labour market participation among MG patients.