I don't think it's a causative relationship. My feeling is that there are a group of disorders related to Dopamine production that overlap with ADHD, for obviou

I don't think it's a causative relationship. My feeling is that there are a group of disorders related to Dopamine production that overlap with ADHD, for obvious reasons, and if you have one of those you're more likely to get diagnosed with ADHD. On the flip side, getting treatment for those disorders, provided you have one of them, can also help with some of the ADHD symptoms.