Image caption Toni was delayed in an acute unit for six months

Mental health patients across the UK are spending years stranded in acute units awaiting discharge, figures show.

Over the past two years, at least 91 patients have waited more than a year to be discharged, with at least seven patients waiting more than two years.

At least 320 patients had to wait at least 100 days to be discharged, BBC Freedom of Information requests show.

Experts say a lack of suitable accommodation and wrangling over budgets are to blame for the delays.

'I felt frustrated'

Toni Adeniyi, 32, has spent 15 years as a mental health inpatient, suffering from emotional unstable personality disorder, and schizoaffective disorder.

"At times I wasn't well, I used to attack people, I wasn't taking my medication properly. I just wasn't allowed off the unit," she said.

However, when Toni was ready to be released, she was stuck on an acute ward for another six months.

"I think it was due to funding, and paperwork. It was a bit frustrating," she said.

"I used to see other people leaving before me, and I would think, 'I've been ready a long time, and I'm more equipped', but they seemed to get out quicker."

Eventually, she was placed in mental health charity Together's supported step-down unit in Wellingborough, which helped her adjust to life outside hospital.

Image caption Toni hopes to gain more independence by moving to a self-contained flat at the unit

She explained that the transition to the unit, and the freedom to do little things she couldn't do while on a ward, made all the difference.

"It's doing my own cooking, doing things I want to do.

"I can have things in my room like mirrors, razors, glass and aerosols, because you are not allowed that in hospital," she said.

Three year delays

In England, the longest delay recorded was 1,159 days, for a 62-year-old patient at Sussex Partnership NHS Foundation Trust.

In Scotland, the longest delay recorded was 1,200 days, at NHS Lothian.

In Wales, Hywel Dda health board saw a delay of 975 days, while in Northern Ireland, a 76-year-old patient was delayed for 1,235 days at the Southern Health and Social Care Trust.

Due to differences in how the data is recorded, direct comparisons between delays in each nation are not possible.

Five longest delays in England

Sussex Partnership NHS Foundation Trust: 62-year-old awaiting a residential home, delayed by 1,159 days. Sussex Partnership NHS Foundation Trust: 60-year-old awaiting suitable housing, delayed by 868 days. Central and North West London NHS Foundation Trust: 27-year-old originally admitted to A&E, awaiting suitable supported housing. Delayed by 668 days. Pennine Care NHS Foundation Trust: 59-year-old delayed by 602 days. Essex Partnership University NHS Foundation Trust: 65-year-old awaiting a placement, delayed by 583 days.

Supported accommodation 'shelved'

Image caption Dr Kalidindi explained that a shortage of supported accommodation could cause delayed discharges

Dr Sridevi Kalidindi, of the Royal College of Psychiatrists, explained that disagreements between different health bodies over how to fund a patient's placement could lead to delay.

"Where those relationships are not quite right, where everyone feels under a lot of pressure in terms of their own finances that's often where people can disagree," she said.

She also said the benefits cap was making it harder for providers to meet demand for accommodation for patients in the community.

"We know around the country of supported housing placements closing down as a result of this.

"We also know of supported housing that was going to come online being shelved by large housing providers who are in this space."

Five authorities with highest percentage of beds in delay

NHS Tayside: 29.4% Hywel Dda Health Board: 20.0% Sheffield Health and Social Care NHS Foundation Trust: 17.1% Hertfordshire Partnership University NHS Foundation Trust: 15% Kent and Medway NHS and Social Care Partnership Trust: 12.3%

The report of the Crisp Commission into mental health care last year found one in six acute patients were clinically well enough to be discharged but could not be for other reasons.

Some authorities reported as many as 29% of their acute beds being used by patients in delay on 28 February 2017.

Most mental health authorities across the UK saw at least one patient delayed by six months over the period.

Lack of correct support

Image copyright Julie Quiery Image caption Julie's daughter Naeema has suffered from anorexia since the age of 13

One such patient struggling to find the correct care is Naeema Austin Quiery, 16, who has suffered from anorexia nervosa for three years.

Her mother, Julie Quiery, says while Naeema has been helped to keep up her weight, the underlying mental health issues have not properly been treated.

"She hasn't received the psychotherapy care that she needs in order to try and overcome her illness," Julie explained.

Julie thinks her daughter has often been discharged too early, once her weight was restored, leading to re-admission.

"It's a very short-sighted view. Because unless you are working with the mental health, and the thoughts and behaviours around the illness, one can't work without the other."

"It has to be a two-pronged approach", she said.

Image caption Julie says her daughter has not been receiving the psychotherapy that she needs

A spokeswoman for NHS England said: "The NHS is now increasing alternatives to hospital admissions."

"There is an extra £400m for crisis resolution home treatment teams, as well as investment in community mental health services."