He said delays in discharging hospital patients into social care at home cost£69m in 2006-07, when the number of delays fell but their length increased.
The scale of the problem was distorted where councils and the NHS had an agreed period after a patient was declared fit for discharge during which they would remain in hospital and not be counted as a delayed transfer into care.
“This masks the extent of the problem and underestimates the impact on the independence of vulnerable people,” Mr Colman said. He urged the government to develop a policy, “which includes how long it is reasonable for a vulnerable elderly person to remain in a hospital bed awaiting the placement of their choice”.
The Welsh Local Government Association said fewer than a third of delayed discharges were the fault of social care.
Moyna Wilkinson, joint lead director on older people for the Association of Directors of Social Services Wales, said: “It is important that delayed transfers of care are not seen as a problem solely at the point of discharge. Factors such as confidence, isolation, family contacts can be important determinants in health.”