A record number of 883,727 patients are now on some form of National Treatment Purchase Fund (NTPF) waiting list, according to new figures.
At the end of April, 630,305 patients were waiting for an outpatient appointment, 76,972 patients for inpatient or day case treatment and 34,394 for an endoscopy.
Currently 21,096 people have been given a date for their inpatient/day case or endoscopy procedure, 90,013 patients are recorded in the planned procedure category and 62,002 of these patients have indicative dates in the future or have an appointment.
The Irish Hospital Consultants Association (IHCA) president Alan Irvine called it a "very disappointing performance".
He said the Scheduled and Unscheduled Care Performance Unit (SUCPU) set up by the Department of Health in late 2017 had not delivered.
The IHCA blamed the waiting list on the fact that one in five permanent hospital consultant posts have not been filled.
Consultants say that despite the existence of the dedicated unit set up at the Department of Health in late 2017, an additional 130,000 people are now awaiting an outpatient appointment to see a consultant - an increase of 26 per cent over the past three-and-a-half years since its establishment.
Prof Irvine said: "The Department of Health's unit should be an imaginative solution-focused hub and incubator for new ideas.
“This requires shared leadership and collaborative engagement with hospital consultants who provide the medical and surgical care and their representatives to ensure an improved public hospital service for the Irish people.”
The IHCA has said the low number of consultants due to the difficulty in filling permanent consultant posts is the root cause of the waiting lists.
The association says it is likely to worsen in the coming months as more restrictions are lifted and people who have put off seeking care enter the system.
Sinn Féin health spokesperson David Cullinane TD said the figure was closer to a million when a 176,408 drop-in outpatient referrals were taken into account.
He warned of a “tsunami of missed care” as a result of waiting lists dating back to 2019.
“That is going to have serious consequences for patient health and wellbeing,” he said.
“This represents a serious shortfall in healthcare delivery that will need to be caught up on urgently to prevent conditions from getting far worse.”
