NHS Digital figures show that 7,055 older people in Lincolnshire have a dementia diagnosis, however the number of those living with the condition is estimated to be around 11,403, and research by the Alzheimer's Society predicts that the number will swell to 17,940 in 2030.
Marking Dementia Action Week, the charity warns that a lack of drugs to cure or slow down the condition means families rely on social care that is often inadequate.
Kate Lee, chief executive officer at the Alzheimer's Society, said: “Lack of time and dementia-specific training among the often overworked and underpaid care workforce means people with dementia aren’t getting the support they need to live.
"From the man with dementia forced to choose between a hot meal and a wash during a home care visit, to the woman rushed to hospital dehydrated because carers weren’t trained in dementia – poor care is all too common.
“Decades of chronic underfunding and neglect have led to a care system that’s difficult to access, costly, inadequate, and deeply unfair.
“This cannot be the kind of society that we expect today and that we want to grow old in."
The charity estimated the total cost of caring for people with dementia in Lincolnshire to be of around £520 million, with the figure expected to increase to £850 million by 2030.
Across England, the health and social care cost for those with dementia is expected to reach £50.5 billion when the unpaid support from family and friends is factored in.
The costs refer to the entire sum required to support older people living with dementia, rather than the extra cost of dementia care alone.
Ms Lee added: "The legacy of this terrible year must be a reformed social care system, which is free at the point of use and put on an equal footing with the NHS.
"That’s why Alzheimer’s Society has launched its Cure the Care System campaign this Dementia Action Week, calling on Governments to honour their promise to rebuild the broken social care system with a concrete budgeted plan, including a funding solution – because dementia isn’t curable yet, but the care system is."
The Government came under fire after it failed to announce clear plans for a social care reform during the Queen's Speech earlier this month, despite the Prime Minister pledging to overhaul social care when he was elected back in 2019.
The Department for Health and Social Care said the reform and funding arrangements are complex and options to deliver the commitment are under consideration.
A spokesman said: "We are committed to significantly increasing research funding to improve detection and care for people living with all kinds of dementia, and as part of our 2020 Challenge on Dementia, the Government has already spent £344 million on dementia research in the past five years.
“We have pledged to improve adult social care to give everyone who needs care the dignity and security they deserve and are committed to bringing forward a long-term plan to reform the social care system later this year.”