A KMPT spokesman said full investigations were carried out into the three Regulation 28 incidents and immediate action taken.
They added: “Patient and staff safety is our absolute priority.
“We take all incidents seriously, act upon and take learning where possible. We have responded to the Regulation 28 reports and have set out the steps we will be taking.”
In the same period 465 patients went missing while in the trust’s care.
The trust was unable to give figures for individual hospitals due to data protection concerns and could not say whether they were secure or open centres.
The highest number were in Canterbury, where the trust filed 207 missing persons reports from KMPT’s rehabilitation unit and St Martin’s Hospital inpatient units.
In Maidstone, there were 91 incidents, the third highest in the county, with the trust providing inpatient care at five sites in the town.
These are: Hermitage Lane’s Priority House and the Trevor Gibbens Unit, the rehabilitation centre at 111 Tonbridge Road, the eating disorder service in Oakapple Lane and a detoxification centre in Upper Fant Road.