A total of five of the old 19th century psychiatric hospital buildings were still open and housing patients at the end of 2013, according to the Mental Health Commission (MHC).

According to the MHC, these hospitals were housing 179 patients at the end of last year.

The hospitals are St Davnet's in Monaghan, St Ita's in Portrane, St Fintan's in Portlaoise, the Central Mental Hospital in Dublin and St Joseph's in Limerick.

Since 2007, 10 old psychiatric hospitals have been closed down, including St Brendan's Hospital in Grangegorman, Dublin.

Back in 2007, there were 1,551 patients being treated in 15 hospitals in their original 19th century buildings.

In the late 1950s, there were over 20,000 patients accommodated in these hospitals. The number of patients started to drop considerably the 1980s with the introduction of community mental health services and acute psychiatric units in general hospitals.

Referring to old hospitals currently in use, the MHC, in a report, said Blackwater House in St Davnet's in Monaghan continued to accommodate 22 residents in its 19th century building, and this was unsuitable for the provision of a modern mental health service.

There are currently 93 patients in the Central Mental Hospital. The MHC says the current plan is to move this hospital to new premises on the campus of St Ita's in Portrane, North Dublin.

The policy for many decades of housing thousands of people, not all of whom whom would have had mental illnesses, in these institutions has been raised again recently following the revelations about mother and baby homes.

There have been calls to extend the planned statutory inquiry into mother and baby homes to mental hospitals , particularly in light of the number of deaths that occurred in these institutions in the past.

In 1932, 1,070 patients died in psychiatric hospitals, while in 1959, the deaths total was 1,082.