The older people's commissioner in Northern Ireland warned Edwin Poots about closing residential care homes more than a year ago, it was revealed.
Claire Keatinge told the health minister a timetable for the changes should have been clearly set out and overseen by his department on a regional basis during a briefing more than a year ago.
The Health Minister has apologised "unreservedly" for stress felt by the residents of homes due to shut and halted the process for six months after health trusts announced the controversial step recently.
Ulster Unionist MLA Roy Beggs said: "Bearing in mind that the health minister was warned of the potential pitfalls more than a year ago, it is even more incredible that he permitted the disaster which emerged in the last fortnight to occur.
"The commissioner for older people gave him 12 months' warning of what could go wrong. That the minister ignored her advice merely compounds his shame."
It was announced recently that 18 NHS care homes would close, affecting 307 residents. Some elderly people felt they had not been properly consulted.
In what critics branded a u-turn, Mr Poots instructed all five health and social care trusts, which run services, to drop contentious plans to close the State-run residential homes and said the matter would be handled by the central Health and Social Care Board instead. He said he never supported the trusts' proposals in the first place.
The commissioner's briefing document from April last year warned: "The effect a home closure has on residents' health and psychological well-being is likely to be influenced by the way in which a home is closed and the relocation managed.
"It is possible to manage the process of relocation into another care arrangement in ways that are least damaging for the residents involved."
The briefing note covered a wide range of issues relating to good practice. These included a recommendation that minimising any adverse impact on the current residents has to be at the heart of the process of home closures.
Other suggestions included:
:: The planned manner of home closures should be led and developed on a regional basis through the health department.
:: The process of care management planning should be clearly set out.
:: Independent advocacy support should be available to all residents who are affected by the home closure process.
:: A clear communications plan through the DHSSPS (Department of Health, Social Services and Public Safety) should be in place.