The true toll of the NHS winter crisis has been revealed by analysis showing that patients who spend 12 hours in A&E are twice as likely to die within 30 days.
An Office for National Statistics report examined the impact of hospital delays in 2021-22.
Risk of death within a month after discharge was 2.1 times higher for patients who spent 12 hours or more in A&E before being admitted or sent home, compared with those who spent two hours or less.
It rose by 1.9 times for those spending nine hours, 1.6 times for those spending six hours, and 1.1 times for three-hour stays.
The analysis included patients classified as “very urgent, urgent, standard or low” but not those with “potentially life-threatening, critical conditions” who are more likely to die soon after reaching hospital.
The increase in risk was even more dramatic among younger patients, with odds 4.6 times higher for 20-year-olds facing the longest waits.
It was also significantly higher patients in London, those seeking care for eye problems, and those who were not admitted to hospital following their visit.
Figures typically used to describe A&E waits only count the time between a decision to admit a patient and when a bed is found.
Analysis by the Lib Dems found these so-called trolley waits had reached unprecedented levels, with more than half a million breaching the 12-hour mark in 2024.
But the picture becomes even more stark when waiting times are measured from the point of arrival. Provisional NHS figures show 1.75 million people spent longer than 12 hours in departments after arriving at A&E last year.
Such delays affected almost 167,000 patients in December as hospitals came under intense pressure from soaring winter virus cases and cold weather.
Professor Julian Redhead, NHS national clinical director for urgent and emergency care this week warned that hospitals were “not out of the woods yet” despite flu cases peaking.
He said: “Staff are working incredibly hard in sometimes challenging surroundings, but winter viruses are much higher than usual for this time of year, and this coupled with the cold snap and problems discharging patients means hospitals are jam-packed with patients – even as more beds have been opened to manage increased demand.”
Meanwhile, analysis of the Government’s plan to ensure 92% of patients receive planned treatment within 18 weeks suggests the NHS will need to carry out millions of extra treatments.
The number of people being removed from the waiting list would need to increase from 20.8 million a year last July to 23.5 million a year in July 2029 in order to hit the target, the Health Foundation concluded.
It said such a feat “looks achievable based on historical trends, but whether it is enough to meet the 18-week standard will also depend on how fast referrals increase”.
Tim Mitchell, president of the Royal College of Surgeons of England, said the research “should offer food for thought to the government”.
He added: “Too many patients are enduring months of pain and anxiety on waiting lists and it is positive that the NHS has set out a clear plan for how it will improve waiting times for patients.
“The NHS can only work within its means…at the current pace of improvement, the government may fall short of meeting its 92% target by the end of this Parliament.
“Success will require the proposed reforms to work and investment in NHS infrastructure, updating IT and strengthening the surgical workforce.”