What are you disclosing? If it's personal information, you aren't required to give any information to your employer, as you are covered under HIPAA. Prior work experiences, whether good or bad, can only help by being shared. Part of problem solving and team work is being able to adapt to different situation, and knowing how each individual works will allow them to be used appropriately in a team.
When you are interacting with people in the work place, the amount of personal information you give out should be limited to just enough for you to get the job done. You can share your past experiences in different projects or positions, but you may want to limit that to a professional level. As you get to know the people and the company better, you will get the feel of how personal and intimate the group is.