Nearly 2.5 million bed days have been lost to NHS hospitals in England in the past five years as older people wait to be moved to social care, according to analysis by a charity.
Age UK calculated that the average number of patients kept in hospital unnecessarily because social care was unavailable increased by 19.3% between 2013/14 and 2014/15, with 44% more people waiting for health and care packages at home compared with the previous year, and 32.8% more patients waiting for a place in a nursing home.
The charity said 2,431,120 bed days were lost to the NHS between June 2010 and March 2015, including 215,662 days that people were waiting for a nursing home place to become available and 206,053 days they spent needing help from social care workers or district nurses before they could return to live in their own home.
Not only is this upsetting for the individuals and their families and detrimental to their health but it also comes at a huge cost to the taxpayer, Age UK said, costing £669 million to keep people in hospital waiting for social care.
The charity said that an NHS bed costs on average £1,925 a week, compared with about £558 for a week in residential care or £356 for home care based on three hours of care per day over the course of one week.
It said these waits for care and support outside hospital are happening against the backdrop of £2.4 billion cuts from social care budgets for older people since 2010, mostly as a result of reduced funding for local government from central government, and therefore local authorities are finding it more and more difficult to provide the social care people need.
Caroline Abrahams, charity director at Age UK, said: "These figures show that year on year, older people are being trapped in hospital in ever greater numbers because of a delayed assessment, care home place, home care package or home adaptation.
"Without decent social care when discharged, whether to their own home or to a care home, hospital stays are often much longer than they need to be and older people are more likely to be readmitted because their recovery stalls.
"Not only would a properly resourced social care system transform many older people's lives and make sound financial sense, more people of all ages could also get speedier treatment in hospital when they need it.
"Policy makers must face up to the fact that an ageing population means increasing numbers of older people needing good social care, and unless and until we provide it the pressures on our hospitals will become more and more unsustainable."
Elliot Dunster, head of policy, research and public affairs at disability charity Scope, said: "Today's figures confirm that the care system is on its knees.
"Chronic underfunding of adult social care has seen dramatic year-on-year rationing of support, leaving many disabled people without the care they need to get up, get dressed and get out of the house.
"People become isolated, can't live on their own and slip into crisis. The health service is often forced to pick up the pieces.
"The Government urgently needs to address the crisis in care funding to prevent the care system from total collapse in the next decade."
A Department of Health spokesman said: "In fact, over the last five years the proportion of older people delayed in hospital because of social care has been improving - and we're going further with the £5.3 billion Better Care programme, which is joining up health and social care services for the first time.
"Next year, there will be 84,400 fewer days spent unnecessarily in hospital as a result, and our plan to create a seven-day NHS will take this even further."