This week, pharmaceutical giant CVS announced it was preparing to buy the insurance company Aetna for $69 billion.

The merger could have a profound impact on the way Americans receive healthcare — and it also raises a number of privacy concerns, said medical ethicist Arthur Caplanat the NYU School of Medicine.

"I think CVS and other big pharmacy chains are going to get more into the business of delivering primary health care services," Caplan said.

That development will have mixed results, Caplan believes. On one hand, easier access to medical care could increase the likelihood that people will actually visit the doctor and reduce the number of unnecessary emergency room visits, he said. 

"That's okay, as long as everybody is qualified and so forth. That sounds like an easier way to get primary care for many people," Caplan said.

But Caplan is concerned that insurance companies could use a patient's medical information against them.

"If these big insurance companies own CVS, are they going to start underwriting you and saying 'you're not compliant...[you] never fill your prescriptions, I don't think that's a person we want to insure anymore?'" he asked.

"When you merge in with a big insurance company, boy, it's the end of privacy," Caplan said.

Click the audio player above to hear the full interview with Art Caplan.