I would not mind too much about medical information being shared;
a, If it was secure and completely anonymous (why they can't just remove the name and day of birth records before handing them over is beyond me)
b, Independant regulation and monitoring, with harsh penalties for breaking the rules.
c, It was provided to public and private sector entities that could actually do good and progress the healthcare system, i.e. University medical research, pharmaceutical companies, care providers, etc. Not just for insurance companies to target individuals to inflate already grossly over priced premiums, or market research and advertising.
But lets be honest, it's is about the money, and always will be.