The number of outpatients enduring long waits for appointments increased by almost 40 per cent last month, despite a promise by Minister for Health Leo Varadkar to eliminate such delays.
Some 13,763 outpatients were waiting more than 15 months for an appointment at the end of January, according to new figures, up from 9,887 a month earlier.
Mr Varadkar had pledged to eliminate waits of more than 15 months by the end of last year, but failed to meet the target despite additional health spending of more than €50 million.
The increase is most likely due to outpatient appointments being cancelled due to emergency department overcrowding and the threat of industrial action by nurses in some hospitals.
The overall outpatient waiting list has also grown, reversing a downward trend in recent months, according to the figures from the National Treatment Purchase Fund.
There were 383,713 outpatients on the list in January, up by more than 8,000 from 375,440 a month earlier.
The number of outpatients on the list peaked at more than 414,000 in mid-2015.
Overcrowding
The problem of long waiting lists is concentrated in a handful of hospitals, many of which are struggling with emergency department overcrowding.
Beaumont Hospital in Dublin has more than 2,000 outpatients waiting more than 15 months for an appointment.
Tullamore, Tallaght and Galway hospitals also have high numbers of long waiters.
Delays are worst in ear, nose and throat departments, orthopaedics and dermatology.
Almost a year ago, Mr Varadkar set a target that no patient would be waiting for more than 18 months by mid-2015 and for more than 15 months by the end of 2015.