Does it make a difference if i have went to the united states or not regarding my renewal?

I have a tourist US Visa but wasnt able to use it bec.of medical reasons. it was granted 1993 expired 2003 muliple entry. Now that im planning to renew it will it affect my status bec. it wasnt used? or will the chances of approval be high if it was used? or it doesnt really matter whether it was used or not.