* 70% of Americans are currently using some form of prescription drug. Would you be comfortable if this information was given to, say, the next employer you interview with?
* Many health issues can be embarrassing for people, even relatively benign ones. This isn't always obvious until you've experienced it.
* Mental health issues often carry a social stigma. Yet 11% of the American population currently take antidepressants.
* Health records, by necessity, include vast amounts of personal information that isn't directly medical. Addresses. Phone numbers. Social security numbers.
from CDC/NCHS Data Brief: "Antidepressant Use in Persons Aged 12 and Over: United States, 2005–2008": http://www.cdc.gov/nchs/data/databriefs/db76.htm
"Nearly 70 percent of Americans are on at least one prescription drug, and more than half take two, Mayo Clinic and Olmsted Medical Center researchers say."
from Mayo Clinic, "Nearly 7 in 10 Americans Take Prescription Drugs, Mayo Clinic, Olmsted Medical Center Find": http://www.mayoclinic.org/news2013-rst/7543.html
I would never have guessed that the number of people taking antidepressant drugs would be so high.
Except it can leave you vulnerable to blackmail. Say your rash is a symptom of a STD which was caused by a drunken one night stand with a x/y person you met at a bar. "Now you wouldn't your partner to find out would you?" says the guy in guy in the suit...
Other ways health records can be abused if your partner or child needs a transplant and they are way down the waiting list...