I was diagnosed with Autism Spectrum Disorder (ASD) at 50, in the middle of a breakdown, during the COVID years. I was 50. Half a century of tics and habits and obsessions and passions that came and went like weather, of people telling me I was "a bit much," and nobody had a name for it. Me included. Especially me.
So, short answer: yes, you can be diagnosed autistic at 50. Or 60. Or 75. Autism doesn't show up in childhood and then leave at 18. You were born with it, and an adult assessment is looking for something that has been there the whole time, usually buried under decades of coping.
The NHS page on autism assessments describes it pretty plainly. Questionnaires about yourself. Questions about how you behave, your early life, your life now. And sometimes they'll want to speak to someone who knew you as a kid.
That last bit gets complicated at our age. I'll come back to it.
Why so many of us get missed until 50
Here's the thing nobody told me. The way autism is diagnosed today is fairly recent. A guide on adult diagnosis hosted by the Fédération québécoise de l'autisme points out that current criteria were developed in the early 1990s, so a lot of adults went "under the radar" as kids and for a good chunk of their adult lives too.
I was already out of school by then. Nobody was looking at a loud, intense, all-or-nothing young guy and thinking autism. Some days they were thinking "jerk." Some days they had a point.
I wrote a whole post on why nobody saw mine for 50 years, so I won't repeat it all here. The short version is that if you were good at faking it, or just loud enough that people noticed the behaviour and not the reason, you probably slipped through.
Usually something breaks first
For me it wasn't curiosity. It was collapse. The breakdown came first, and the word "autistic" came out of trying to understand why I'd broken.
I don't think that's unusual. The NHS even notes that you can be referred for an autism assessment while you're getting help for something else, because a mental health professional notices the signs. Depression, anxiety, a burnout that won't lift, a marriage on fire. Somebody looks at the pattern instead of the symptom.
If you're 50-something and reading this because something just gave out, that's a pretty common door in. It's a lousy door. But it's a door.
What an assessment looks like when you're older
It's mostly talking. And remembering, which is harder than it sounds.
They want to know whether the stuff you struggle with has been there your whole life, and whether it shows up everywhere (work, home, friendships) and not just in one bad job. That's the core of it. You'll probably fill in questionnaires. The FQA guide mentions common ones like the AQ (autism quotient) and the ADOS, which is an observed assessment.
Now the childhood problem. At 50, your parents might be gone, or old, or they remember you as "a good boy who liked his trains" and nothing else. That's normal and it doesn't sink an assessment. The same guide suggests writing down examples from your own life, as far back as you can remember, and bringing them. If I were starting from scratch, that's the first thing I'd do. Get it on paper before you walk in, because in the room your brain will go blank.
Who actually does the assessment depends on where you live. In Québec there's a public route through the CLSC and a private route through a psychologist. I've laid that out in getting an adult autism assessment in Québec.
Can you just screen yourself online?
You can do a screening questionnaire. The Embrace Autism tests page has free versions of the common ones, with explanations of the scoring (they're a private, autistic-run clinic in Toronto, so keep that in mind). The Autism Research Centre at Cambridge, who made the AQ, also publish theirs.
A screen is a flashlight. It tells you whether it's worth looking. It doesn't give you the answer, and a high score from a quiz at midnight isn't a diagnosis. Plenty of anxious, depressed, burned-out people score high on these things.
Was it worth it, this late?
For me, mostly yes. It didn't fix anything. I'm still the same guy who starts a project with a nuclear amount of energy and then crashes. What changed is I stopped reading every crash as proof I was broken or lazy.
It's a real question though, and the answer isn't yes for everybody. I went into it properly in was getting diagnosed worth it at my age?
If you want one book to read while you wait, this is the one people keep handing late-diagnosed adults:
Unmasking Autism
Devon Price
My take. The book I wish someone had handed me decades ago. Written by an autistic psychologist, about the mask most of us didn't know we were wearing.
Good to know. Very identity-affirming. Some clinicians push back on its take on self-diagnosis.