When patients are hospitalized, they are at much greater risk for having their chronic condition medications unintentionally discontinued rather than restored at discharge, which increases the chance they'll be back in an emergency room, be emergently readmitted, or die.
The lapse in restoring needed prescription medications as the patient leaves the hospital is especially problematic in patients that have been cared for in an intensive care unit.
Those are findings from a Canadian study of nearly 400,000 patients 66 years of age and older who were cared for in Ontario hospitals between 1997 and 2009. The patients had shown stability and compliance because they had been on the medications for at least one year before the study. But after discharge, the report found, as many as 22.8% who should have been on anti-platelet drugs failed to renew prescriptions within 90 days.
The report is published in Thursday's Journal of the American Medical Association.
"Gaps in the continuity of care are an area of vulnerability for patient safety," said the authors, led by Chaim Bell, MD, of St. Michael's Hospital and the Institute for Clinical Evaluative Sciences in Toronto, and colleagues. "We found that patients discharged from the hospital have an elevated risk of not continuing their long-term medications for chronic diseases and that treatment in the ICU appears to further increase this risk."
The study calls for hospital teams to pay increased attention to transitions in care so that medications temporarily and reasonably discontinued during hospitalization are restored when the patient returns home.
The report revealed unintentional discontinuation trends in five drug categories, but the greatest drop-off was in patients' use of anti-platelets and anticoagulants, a class of drugs which also had the highest risk of resulting in an ED visit, emergent re-hospitalization, or death.
But inadvertent discontinuation of other medications had adverse effects as well, including statins, levothyroxine medication for thyroid problems, respiratory inhalers, and gastric acid-suppressing drugs. "Discontinuing a proton pump inhibitor may result in gastrointestinal tract symptoms or peptic ulcer, whereas an unintended discontinuation of warfarin medication in a patient with atrial fibrillation increases the risk of an embolic stroke," they wrote.
Precisely why the drugs were discontinued is unclear and complicated. In ICU settings medications are deliberately suspended if they might interfere with other drugs, such as those used for resuscitation, and drugs used to treat chronic conditions may have side-effects that complicate a critically ill patient.
The researchers suggest also that some medications may not be restarted because they were erroneously thought to have been initiated in the ICU.
The researchers called for "formal programs such as medication reconciliation and standard discharge summaries" to provide a way to improve communication,
In a related editorial, Jeremy Kahn, MD and Derek Angus, of the University of Pittsburgh Graduate School of Public Health, criticized the report in part because, as the authors acknowledged, they could not be absolutely certain that discontinuation of the medications in all cases was not intentional.
"New contraindications may have arisen that were not captured in the investigators' administrative database. Physicians may have used the admission as an opportunity to rethink the original medication indication," they wrote.
And, they said, the patients may have decided that the side effects of certain medications outweighed any benefit, in light of a new condition with which they had to grapple.
But Kahn and Angus said Bell and colleagues did everything they could to minimize this effect, using only medications with solid evidence and strong benefit-to-risk profiles "that are unlikely to be stopped without good clinical reason."
Another possibility, Kahn and Angus suggested, is the finding in the study that patients were prescribed "a median of 12 different medications in the year prior to the hospitalizations, and 75% were prescribed nine or more medications."
"As a consequence, hospital-based physicians increasingly not only must attend to the patient's acute medical problems, but also have to manage an ever-expanding array of complex and unfamiliar medications [which carry...] unknown adverse effects and put patients at risk for unexpected interactions between medications.
"Thus, for some patients, hospital care is now as much about organizing and reorganizing a litany of medications as it is managing acute disease...It is not so surprising that important medications become lost in the mix."