but...

Anxiety is also associated with some medical conditions.

Diabetes, certain heart conditions, TBI and PCS (Post Concussion Syndrome), asthma, hormonal issues especially thyroid problems, people with polycystic ovarian syndrome (PCOS) and many others.

If a person didn't have anxiety as a child and there is a sudden onset of anxiety related issues then it is very important to have a complete physical to exclude other causes.

There is of course the matter of genetic predisposition.

It's not all in the mind.