There are all kinds of biosensors available that don't connect to the Internet. An Apple device presumably will.
There is enough concern with the amount of information being collected with an iPhone. Consumers should be cautious about providing their personal health info with Apple. I would only hope whatever information is stored on Apple servers, it is regulated like other HIPAA info. At the least, if Apple needs to be HIPAA compliant and information is breached, big fines and other penalties will/should follow.