New figures show an average of 132 employees at the East of England Ambulance Service are taking mental health-related leave each month, up from just 37 in 2015.
The trust, which was recently ranked the worst performing in an NHS league table, has faced growing scrutiny over staff welfare.
At the time, union bosses said morale was at “rock bottom” and the new figures will raise concerns about a growing sickness culture at the organisation and the impact that might have on its response times and care for patients.
The data, which was obtained via a freedom of information request, shows that on average last year 121 members of staff were off each month for mental health reasons.
That figure rose to 137 in the first five months of 2025.
The organisation says that its headcount has grown by around 1,000 since 2015, but its monthly mental health absence rates have outstripped that growth, rising from 0.9pc of the workforce a decade ago to 2.64pc this year.
The statistics also paint a wider picture beyond the mental health of staff.
They show that reports of physical assaults on paramedics have more than doubled since 2015, rising from 191 to 412 incidents in 2024.
Meanwhile, staff are leaving earlier than ever – with annual resignations more than doubling since 2016 and the average length of service dropping from 10.7 years to 8.6.
Caroline Hennessy, UNISON Eastern head of health, said: “Ambulance staff face huge personal challenges every day at work.
“Too often staff are expected to simply absorb whatever’s thrown at them, but without proper support from managers, workers just can’t carry on.
Ambulance staff are also facing a rise in physical assaults(Image: East of England Ambulance Service / File photo)
“And when stress and burnout set in, the situation spirals. Experienced staff quit, leaving bigger gaps and more stress for those remaining.
“The trust must do more to protect the health and wellbeing of staff doing such high-stakes work.”
EEAST said they are investing “significantly” in wellbeing services.
New measures being implemented include a dedicated support hub, 24-hour crisis line, trauma therapists and a new support app.
A spokesman for the trust said: “We take staff wellbeing very seriously and offer a wide range of support.
“Since 2015, our workforce has grown by around 1,000 people. As awareness of mental health has increased, we’ve worked hard to remove stigma and encourage staff to seek help.”