The drugs are so expensive that some people are saying that only those who can and will comply should get them. I think this is scary. On the other hand, it is truly difficult to take all the meds we have to take the right way. Great question, and a tough one. I don't know of any other disease in which compliance is so important.
Doctors often make decisions about therapy based on compliance.
In fact, study after study has shown that you cannot predict compliance based on anything except past compliance. The one exception might be active drug use, though even that has to be individualized. Ideally, this decision is made after a frank discussion with the patient. This patient was an alcoholic who came to about a quarter of her clinic visits. T usually lasted her for about six months.