This is medical data. "Open repository" and "medical data on individuals" doesn't really mix well. Ask the next person denied health insurance based on an open access fmri scan (Just to name the most basic/trivial example).
In fact, "simpler" things like heart rate etc, are not so simple, as mixed with other factors that are needed for control, such data can be surprisingly hard to meaningfully anonymize. I'm not saying we should give up on open medical data, but it is definitively different from eg: open data regarding a physics or chemical experiment, material science etc.
[ed: There's of course projects to collect data, but limit access - in that sense it can be "open" but one would need permission approval to work with the data. There are many such projects, like for Norway, for questionnaires and similar research: http://www.nsd.uib.no/personvern/om/english.html - research that uses standard clauses for possible re-use is also available to be combined with new studies and meta-studies. Often these data are only available in aggregate and/or anonomyzed form.]