Another interesting finding of the study was that people who did take their medications regularly also tended to do other things right when it came to their health.
"We believe better compliance with medications also tracks with other more favorable behaviors," said Dr. Marc A. Pfeffer, professor of medicine at Brigham and Women's Hospital in Boston. "We found that patients with heart failure that took more of their medications did better -- even those [taking] placebos."
"It might not be just the effect of the medications. It might be a marker of patients that don't pay as much attention to their health," Gehi adds.
Despite all of the data showing the profound effects of medication noncompliance, the most important question remains: How do we fix the problem?
"Better patient education regarding the need for following directions and information [about] side effect" may help improve compliance, says Rubenfire. He adds that getting the message across to patients that while there may be side effects and toxicity associated with their drugs, the benefits of taking their meds may outweigh the risks of skipping them.
As for reducing the financial burden of ongoing prescription drug use, Rubenfire suggests using "generic drugs, combination drugs and once per day [drugs] if possible to reduce doses and numbers of pills."
The study did have its weaknesses. Whooley said the research does not look at specific medications, and the study population may not have been entirely representative of everyone who takes prescription medications.
"The patients were mostly men, so it's unclear whether the same relationship would be true for women," she says.
But overall, the authors believe the study plays an important role in emphasizing the importance of compliance.
"I think it's a fairly straightforward study with a pretty simple message," said Gehi. "Physicians, patients and the public health sector need to pay more attention to adherence."
"It's not rocket science -- taking the medicines as your doctor tells you to is actually going to prolong your life," says Whooley. "That's the take-home message."