Interest on the debt was $263 billion in 2017 and $310 billion in 2018. That's not the reason for most if the increase in the deficit. Medicaid, Social Security, and Defense are the reason. Interest on the 10 year T-bills actually went down. The increase in interest expense is due to the increase in debt.
The elephant in the room is the size of the federal government. Trump submitted a budget that would not have added to the debt. He did it by slashing useless agencies like the CPB. Speaker Ryan took one look at it, tossed it in the trash, and passed a bloated bill just like always.