The squeeze on public spending and the drop in nurse numbers since 2010 has contributed to 120,000 unnecessary deaths in England, according to new research.
There could be as many as 100 excess deaths a day from now on if the NHS does not get an urgent cash injection, a study found.
Over-60s and care home residents were found to be the most at risk, with researchers establishing nursing numbers to be the most important factor determining premature death.
The research, published in the British Medical Journal, found that between 2001 and 2010 the number of nurses rose by an average of 1.61% every year.
From 2010 to 2014, the rise was just 0.07% – 20 times lower than the previous decade – while spending on social care fell 1.9% every year over the same period.
It found the number of deaths in England fell by an average of 0.77% every year between 2001 and 2010, but rose by an average of 0.87% every year between 2011 and 2014.
Researchers at the Department of Applied Health Research at University College London said it would take an extra £6.3 billion every year to plug England’s “mortality gap”.
The sum takes into account the increase in the number of people living beyond the age of 85, who are the most likely to need social care.
The number of people aged 85 and over is expected to reach 1.8 million by 2020, up from 1.6 million in 2015.
Every £10 drop in spend per head on social care was associated with five extra care home deaths per 100,000 of the population, the study found.
Researchers predict that more than 150,000 deaths between 2015 and 2020 will be linked to lack of funding, or the equivalent of 100 deaths every day.
The authors said the study indicated lower spend on health and social care is “associated with a substantial mortality gap”, but warned that it was an observational study based on observational data and no firm conclusions could be drawn.
Janet Davies, chief executive of the Royal College of Nursing, said: “This is yet more evidence that links the current shortage of nurses with increased patient mortality.
“Despite years of warnings, all parts of the NHS and social care system do not have enough nurses and people, particularly vulnerable and older individuals, are paying the highest price.”
She added: “For too long, the Government has allowed nursing on the cheap. Hospital wards and care homes alike increasingly rely on unregistered healthcare assistants, especially at night.
“Ministers cannot ignore further evidence on the risks of these shortages.”
Elsewhere, Caroline Abrahams, charity director at Age UK, said: “If these findings are anything like true they are incredibly worrying and they certainly reinforce the case, which is already very strong, for a big injection of funds into the NHS and Care in next week’s Budget.
“Anyone who works with older people in poor health, with growing care needs, knows that not only the quality of their lives but sometimes their sheer survival depends in large part on the skill and dedication of health and care professionals and the timely availability of the right treatment and support.”
A spokesman for the Department of Health said: “As the researchers themselves note, this study cannot be used to draw any firm conclusions about the cause of excess deaths.
“The NHS is treating more people than ever before and funding is at record levels with an £8 billion increase by 2020-21.
“We’ve also backed adult social care with £2 billion investment and have 12,700 more doctors and 10,600 more nurses on our wards since May 2010.”