I understand where you are coming from. However the term you are looking for is "categorical" rather than "acute". The terms "acute" and "chronic refer to duration and intensity rather than presence or absence. The alternative to "categorical' is "dimensional". (as an aside , it is estimated...
ADHD is a disorder which is dimensional, ie, you can go from very little to very much. The rational view is that when the aspects central to ADHD, of impulsivity, distractibility and disruption of attention become such that they interfere with your ability to carry out normal life functions ...