A Birmingham consultant says he is disappointed a Worcestershire hospital has been criticised for its care, eight months after he first raised concerns.
Dr Michael Bond complained his father Harry, 85, was ignored and treated without dignity during his stay at the Alexandra Hospital in Redditch in June.
It is also failing in other parts of its elderly care, an NHS watchdog says.
The hospital accepts the watchdog's findings. It apologised to Dr Bond and invited him in to discuss his concerns.
The Care Quality Commission (CQC) has published its first report into dignity and nutrition for older people in hospital and said in some cases Worcestershire Acute Hospitals NHS Trust, The Ipswich Hospital NHS Trust and the Royal Free Hampstead NHS Trust in London had not helped elderly patients to eat and drink and their dignity had not been respected.
Dr Bond, a consultant forensic psychiatrist at the Reaside Clinic in Rubery, said his father had been admitted to the Alexandra Hospital on 4 June last year, following a fall at home in Bromsgrove.
On 9 June he was released from hospital into a nursing home. He was readmitted to the hospital as an emergency patient on 21 June and died from internal bleeding on 25 June, 2010.
Dr Bond said: "I started to warn staff that he had had problems before with internal bleeding on the medication they had put him on when he was admitted, but nobody took any notice."
Mr Bond's granddaughter Emily said: "The standard of care was very bad.
"It was very distressing really to see, he had slid down the bed and was just left there with no-one noticing or paying him any attention.
"The water was often out of reach and he was dehydrated because he wasn't drinking enough."
Between the first and second admission, Dr Bond wrote to the hospital chief executive to complain about the standard of care as other patients on the ward had shared similar experiences.
Following the publication of the CQC report on Thursday, Dr Bond said: "I worry about the general culture within the hospital, which is such that staff are not talking to patients, or each other, or listening to relatives.
"This problem is too big for one person, one chief executive or manager to solve, it is going to need a lot of resources committed.
"I just worry whether the culture is so ingrained that it is going to be an impossible task."
Dr Charles Ashton, medical director for Worcestershire Acute Hospitals NHS Trust, said the trust had met Dr Bond already and had formally apologised to him for the "deficiencies in care" his father had received.
He added: "We took on board his concerns and did take action at that time. We offered him the opportunity to come back to us if he was not satisfied.
"We have accepted and apologised in relation to the findings in the CQC report, but do not feel these are directly comparable with Dr Bond's concerns."
"As medical director of the trust I would like to meet with Dr Bond to resolve any of his outstanding worries," Dr Ashton added.