A judge was also told prospective patients in the Province are nearly 50 times more likely than those in Wales to face a year-long wait for care.
The figures were disclosed in a joint legal challenge by two women from Belfast over hold-ups in providing them with treatment.
May Kitchen, 77, and Eileen Wilson, 48, claim the authorities have unlawfully failed to provide them with necessary medical care within a reasonable time.
In the first case of its kind in the United Kingdom, they allege failures to meet the minimum legal standards in the running of a health service and a breach of their human rights.
But their barrister argued that everyone in Northern Ireland could be exposed to the ordeal of spiralling waiting lists.
Ronan Lavery QC said: “This is a problem right across the board, and it demonstrates the catastrophic nature of it.”
Mrs Kitchen, a retired nurse who lives alone in north Belfast, was diagnosed with cataracts in 2015.
Amid fears that she would lose her sight, the pensioner was told that the waiting list for surgery was 42 months.
The pensioner eventually used medical insurance for private treatment, but insists she should not be out of pocket due to her entitlement to free healthcare.
Ms Wilson, a mother of six from east Belfast, has been seeking an urgent consultation with a neurologist about her suspected multiple sclerosis since June 2017.
In proceedings centred on alleged delays predating the pandemic, judicial review challenges have been brought against the Department of Health as well as the Belfast and South Eastern Health and Social Care Trusts.
Northern Ireland’s Commissioner for Older People, Eddie Lynch, has intervened in the case to support Mrs Kitchen’s challenge.
With 40% of people on waiting lists aged over 60, the court heard that the elderly are being disproportionately affected by the delays.
Their quality of life in later years could become so intolerable due to the impact of the wait for medical care that some may feel life is less worth living, it was contended.
“Wherever that line is drawn, we are far beyond it in Northern Ireland,” Mr Lavery said.
Citing situations where people wait years for hip replacements, he claimed: “There is effectively nonfeasance.”
During submissions he set out a series of bleak findings in a report by Ulster University Professor Deirdre Heenan on the “gulf” between waiting lists in Northern Ireland and the rest of the UK:
l By September 2021 one in four people were waiting to see a consultant for the first time – increasing by almost 10% in a year.
l Over half of patients had been on a list for more than 12 months.
l Some people have been waiting for up to five years for routine orthopaedic treatment, four years for ear, nose and throat procedures, and up to seven years for urology appointments.
Mr Lavery stressed: “Another staggering statistic, a citizen in Northern Ireland was at least 48 times as likely as a person in Wales to wait more than a year for care.”
The court also heard that by last September more than a quarter of a million people within the Province had waited longer than 12 months to go into hospital.
Mr Lavery went on: “At the end of September 2021, 191,000 people were waiting longer than 52 weeks for a first outpatient appointment.
“And the number of people waiting longer than one year for a first hospital appointment and elective treatment surged by 23% and 45% respectively between September 2020 and 2021.”
Mr Justice Colton was told no attempt has been made to dispute the figures.
“It seems to be uncontroversial, that’s the state of waiting lists,” counsel said.
Alleging the state has breached Article 8 of the European Convention on Human Rights, he submitted: “There can’t be any doubt that your family and private life is affected by the ordeal of waiting for years on a waiting list.”
When it was put to him that the court should not interfere in clear issues of political strategy and resources, Mr Lavery acknowledged that no judicial direction on policy matters could be made.
“The most the court can do is declare that what is happening at the moment is unlawful, it may even declare that a plan should be put in place,” he added. The hearing continues.