IIRC,
@michaelrack is IM/Psych/Sleep. I could be wrong though.
Although
@DrMetal and I have
very different views on the role of board certification in the ongoing practice of medicine, I'm gong to agree with them here. Unless you have hospital or practice privileges that are contingent on your maintaining IM boards, why would you do that to yourself?
I have no intention of retaking my general IM boards (which actually expire on Friday) since I don't choose to practice general IM any longer. I will keep maintaining my subspecialty boards though.
I do know people who choose to maintain boards unnecessarily as a point of pride, proving to themselves (I assume, since nobody else actually cares) that they can do it. But I have better things to do with my time and money.
Should you decide to continue this route, the LKA is new enough that I don't know that we have good data to support the best study materials. I suspect MKSAP (or the millions of other options out there) will be more than enough.