The number of people on disability benefits in the UK has been steadily rising, despite reforms aimed to reduce that number being introduced, in another signs that the system is under strain.
Analysis from the Institute for Fiscal Studies (IFS), disability claimants have risen from 2% of the working-age population in the early 1990s (591,000) to 6% in 2020–2021 (2.2 million).
The IFS claims that the growth in disability benefit claims has been primarily driven by an increased prevalence of mental health conditions.
Four-fifths of the rise in the number of disability benefit recipients over the past 20 years is accounted for by those with psychiatric conditions as their main disabling condition, making up 44%, or 944,000, of all working-age disability benefit claimants.
Psychiatric conditions include mental health problems and learning disabilities.
The big rise in claims means the disability benefits bill is 70% higher than expected, the IFS said.
Since 2012, the disability living allowance (DLA) has been replaced by personal independence payment (PIP). The reform was intended to reduce spending on disability benefits by 20%.
However, the think tank argues that instead, since PIP started to be introduced, spending on disability benefits has risen and at a faster rate than before the policy change.
Spending just before the start of the pandemic was around £11bn per year, it said, with forecasts from before the reform had expected it to be around £6.5bn.
According to the think tank, this "likely contributes to the link between disability and deprivation", with disabled people now making up nearly half of the most deprived working-age adults in the country, it said.
Heidi Karjalainen, a research economist at IFS and an author of the paper, said: "Over the past three decades, the fraction of working-age people claiming disability benefits has increased from 2% to 6%, with much of the rise driven by growth in claims for mental health or other psychiatric problems.
"This reflects an increasing rate of mental health conditions across society as a whole. If this trend continues – or is even hastened by the pandemic – it will add further pressure to disability benefit spending."
Of the most deprived tenth of the working-age population, 1.5 million (44%) are also disabled, the research found. But 1.1 million of this group do not receive disability benefits.
It found that, of these million disabled and deprived people who do not get disability benefits, 59% are not in paid work. Of those, 58% are women, 77% do not have a degree, 58% are single, and 60% have mental health, social or behavioural problems.
These are all higher proportions than for the overall working-age disabled population.
The research, published on Wednesday, suggests that on average claimants are now waiting around five months between applying for benefits and receiving them.
"In some cases, they do not receive disability benefits because their condition is not of the sort or severity that the disability benefit system supports," said Tom Waters, a senior research economist at IFS and author of the paper. "Others will be eligible but not claim – perhaps because they find the application process too difficult."
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