Since always? It’s a developmental disorder, and a disease is “a disorder of structure or function in a human, animal, or plant, especially one that produces specific symptoms or that affects a specific location and is not simply a direct result of physical injury.”
Pretty much every medical body would list it under its classification of illnesses.
Pretty much every medical body would list it under its classification of illnesses.
e.g. NHS: https://www.nhsinform.scot/illnesses-and-conditions/brain-ne...