The DSM is based on symptoms being present before age 12, but to meet criteria for the diagnosis now requires symptoms to be present now too, regardless of history.
Hyperactivity and impulsivity usually improve over the course of childhood/adolescence. As does executive dysfunction (probably because people learn skills/workarounds). Much of the dysfunction associated with ADHD has to do with the fact that traditional school is an inappropriate environment for kids with ADHD. Once people grow up and can choose a more suitable environment, it causes fewer problems, particularly if there are relatively few psychosocial problems.
Do you know that, or is that a gut instinct? Antidepressants change the architecture of the brain after just one dose; it seems plausible that stimulants over the developmental period of the brain might cause long-term changes—beneficial, perhaps. As in the case with bipolar where medication is known to prevent brain damage from manic and depressive episodes.
I agree with you. I don't really care whether someone even had symptoms as a kids. If they have adhd symptoms now that negatively impact life and meds help, who cares about the epidemiology.
There are some very good population studies of ADHD in the UK, Egypt, Scandinavia, and Australia off the top of my head that are able to trace patients longitudinally much easier due to their national health care registry. Keep in mind that ADHD can be a delay in the formation of the neural pathways rather than just permanent dysfunction. We see teenagers and young adults on a regular basis who age out of stimulants, finding the treatment begins to worsen symptoms or be unnecessary even full brain maturity has been reached (both in hyperactive and inattentive subtypes, although it is certainly true raw hyperactivity is the sx most likely to improve over time).
I have several attendings who regularly tell patients "we know from research that chronic marijuana use will make your anxiety and depression worse." I've tried to find research to back this up and the best I can tell, aside from the relationship with psychosis, the research on chronic use of THC in regards to psychiatric symptoms is inconclusive. My theory is that there are a lot of people in medicine who are biased against substances that make people feel good and cherry-pick studies that confirm their biases. I think if ADHD was treated with SSRIs, no one would care about who "ages out."
I agree with you in general and think your bring up good points. I should have clarified that I was thinking about adults not children/adolescents. Logically, a developing brain is more at risk of a psychoactive substance causing problems. I'm also not convinced that the confounders that the researchers used in the paper you cited are necessarily the most likely confounders. To me, this study does not read as a slam dunk indictment against marijuana use, even in teens.Literally the first google scholar hit for "cannabis anxiety":
Cannabis and Anxiety and Depression in Young Adults: A Large Prospective Study
To examine whether age of first use or frequency of use of cannabis is associated with anxiety and depression (AD) in young adults, independent of kno…www.sciencedirect.com
There is a more clearly established dose-response relationship as regards psychosis for sure, but a) using a lot of marijuana does not seem, at best, to prevent the development of depression or anxiety in people predisposed towards and b) our most successful therapies for anxiety to date all center around not engaging in avoidance and safety behaviors. It is hard to imagine a more pure safety behavior than getting high when you don't feel good. Take the empirical evidence plus a compelling theoretical explanation together and I reckon you have good reason to be concerned that MJ use does not make things better in this regard and probably makes them worse for many people.
