How to use User features(such as age, demographics) to construct the Sequential Recommendation System ?

[np-n]

I want to train a next-procedure prediction for the medical dataset. After checking the data processing pipeline, what I have figured out is: the emphasis is done on the sequence of item interaction for users along with the timestamp in the loaded data. But there is no consideration of user features.
But, what I know is user features and item features also play a role, In my case, user features are very critical. How I can use such features to design the sequential recommendation system? Thank you!