Mental health and substance use evolution in Swiss ED residents: a 6-month prospective longitudinal single-center study.

The challenging nature of emergency medicine places residents at risk of psychological strain and unhealthy consumption habits. Research on the impact of emergency department (ED) work on residents' mental health, substance use, and lifestyle is scarce. This exploratory mixed methods longitudinal study assessed ED residents at Lausanne University Hospital from 2020 to 2022. Residents completed surveys at the beginning and end of a 6-month ED rotation, including validated tools, such as the Maslach Burnout Inventory and the Hospital Anxiety and Depression Scale, alongside direct questions addressing substance use and lifestyle. Semi-structured interviews were then conducted to explore residents' experiences and coping mechanisms. Primary outcomes included changes in burnout, anxiety, depression, and substance use. Secondary outcome was to gather residents' experiences in ED. Of 47 residents recruited, 31 completed follow-up surveys. Emotional exhaustion and depersonalization scores, subscales of the Maslach Burnout Inventory, increased slightly (p = 0.0259 and p = 0.0064), while personal accomplishment remained stable. Anxiety scores decreased (p = 0.0068), depression scores worsened (p = 0.0185), and sleep quality declined (p = 0.0022). Substance use and personal factors, such as religious beliefs and personal development activities, remained stable over the 6-month period. Interviews highlighted themes including patient flow pressure, irregular shifts, and departmental atmosphere. After 6 months in the ED, residents experienced minor changes in mental health with limited clinical significance. Protective factors like senior peer support may buffer against adverse effects. Future research should explore these dynamics in diverse EDs and over longer periods to better understand the impact on residents' well-being.