I briefly searched the forums and could not find any info on if this was changed. My Companion's HP are much less than they used to be. Was this changed at some point? My Max Level Isobel with no armor weapons or jewelry on for instance only has 22.5k HP when she used to have I think 30k and according to this forum post it was 30k at base:
https://forums.elderscrollsonline.com/en/discussion/620245/companions-basics-traits-and-mechanics
I put a lot of coin into purple vigorous gear and now it seems like this was waste! Please let me know if its just a bug or something.