How does living in the UK affect your US credit score?

I am just curious as to whether living in the UK might be having a detrimental affect on my credit score in the US.

If I ever moved back, would I find that I was unable to borrow, due to not having had a track record of spending/paying bills in the US for several years? I do still own a property in the US, and so I have a tenant who pays monthly rent -- that is the full extent of my US financial activity for the past three years, really. Could this be a problem in future?

We've stayed financially active in the US this time, but from 2005-2007 we were not. In fact, DH hadn't any credit at all.

It didn't impact us significantly; we were able to return, rent an apartment and buy a car with relatively little fuss.