Caveat to this post: I don't know too much about motivational interviewing, except that it is a type of interviewing, and isn't it associated with substance abuse treatment? Now I'm wondering--do PCPs get training in this, so they can use it to address smoking, obesity, exercise, etc? I thought it was classified as psychotherapy so my guess is no...
Does the patient need to start out with some motivation or can you start from zero? I wouldn't go out on a limb with this theory but one thing that makes psych patients unique is they don't really present for well patient visits, unlike primary care patients. Also PCPs follow multiple systems which is why they catch things like smoking, when the patient may only care about their knee pain. Psych patients don't come in unless they want to change something about themselves, however much they may actually resist doing so. So although I hate to say psych patients are "motivated" (many are not--many are self defeating even...)--I would think you could try to reach the patient at the level where they want to change, whereas with PC patients, they may have zero motivation to change at all, yet they come to the doctor reliably and take their meds. That's the puzzling thing--people with intact capacity, normal mental status, who yet are damaging themselves with bad habits!
Is there something out there that can help move a person from zero to 0.1 motivation on issues like exercise, smoking, etc? Can MI do that?
In any case this would have been helpful to me earlier today with my 350 pound smoker s/p hemorrhagic stroke now with TIAs and chest pain, who know he should quit smoking and walk more but won't even give a smoking cessation class a try!