In England, the rates of adult autism and psychotic disorders paint a striking picture of stability—or, depending on how you look at it, stagnation. Autism prevalence has been stuck at about 1 in 100 adults, a mere 0.8%, since at least 2007. That’s right, decade after decade, no significant rise. Meanwhile, childhood diagnoses are skyrocketing. So, what gives?
The fifth Adult Psychiatric Morbidity Survey (APMS) conducted interviews with nearly 7,000 adults, which included both diagnosed and undiagnosed cases, confirming that autism rates haven’t budged. It seems adults are being left out of the diagnosis party. Over 89% of middle-aged and older autistic adults in the UK are still wandering around undiagnosed, especially those over 40. And let’s not even get started on the waiting lists for autism assessment—193,203 people in England are in limbo, waiting for help. That’s a staggering backlog! Furthermore, many autistic individuals do not use mental health services at higher rates than non-autistic adults. Additionally, a 2023 study estimated that 150,000 to 500,000 individuals aged 20 to 49 in England may be undiagnosed.
Over 89% of middle-aged autistic adults remain undiagnosed, highlighting a significant gap in support and assessment.
Then there’s psychotic disorders. They’re not rising either. Prevalence remains at a comfy 0.4%, unchanged since 2007. Most people with psychotic disorders are getting treatment, which is nice, but the rates aren’t budging. It’s almost like a game of freeze tag, but nobody’s winning.
Despite the stability in reported rates, the situation feels dire for many autistic adults. Undiagnosed individuals are at a greater risk for social isolation and poorer health outcomes, especially as they age.








