Heart Disease News:

Clot-Busting Drugs Add to Risk for Oldest Patients

Harvard Medical School researchers have added to the growing body of evidence that clot-busting drugs known as thrombolytics increase the overall risk of death for the very oldest patients.

The study, published in the March 11 Archives of Internal Medicine, found that eligible patients between the ages of 80 and 90 who received such drugs had a 40 percent greater risk of death in the hospital compared with patients who did not receive the drug.

The researchers examined records of 2,659 patients with acute myocardial infarction admitted to 37 Minnesota community hospitals from 1992 to 1996. Of this group, 719 patients were eligible for thrombolytic therapy according to the guidelines.

The study found several reasons why elderly patients may not share the benefits of this therapy seen in younger patients. The elderly are more likely to have contraindications, their risks for bleeding and stroke are markedly increased and they tend to experience longer delays between symptom onset and hospitalization that substantially reduce the drugs' effect on survival.

"The oldest patients, even those without contraindications to therapy, experienced an excess risk of mortality compared with untreated patients," the authors write. "Findings of this study suggest a need to re-assess our approach to the use of thrombolytic therapy in the treatment of acute myocardial infarction patients older than 75 years."

A study from John Hopkins University, reported on in the May 16, 2000 Circulation, showed similar results: patients over age 75 who got thrombolytic drugs were nearly 40 percent more likely to die within 30 days than patients not receiving the drugs.

The Harvard Medical School research suggests that national guidelines on the use of these drugs such as streptokinase and tissue plasminogen activator should be applied with greater selectivity, and possibly revised, to maximize benefit and minimize risk due to bleeding or stroke, said lead author Stephen Soumerai, professor of ambulatory care and prevention at Harvard Medical School and Harvard Pilgrim Health Care.

Soumerai told Medical Week that the study means that physicians should "certainly be more vigilant" in selecting appropriate candidates for treatment regardless of age.

"Doctors should be more certain than they have been in prescribing drugs to the oldest patients," Soumerai said, while adding that he and his colleagues would never go as far as to issue a blanket recommendation that such drugs should never be prescribed to such patients. "A physician has to use his or her judgment. That's what we're saying."

Soumerai said family members advocating for an elderly heart attack victim should take into account all of the existing data that questions the efficacy of clot-busting drugs on the oldest patients.

For family members accompanying a loved one having a heart attack to the hospital, Soumerai said they could speak to the staff based on their knowledge of the data, express their opinions and have a shared discussion with physicians. He said family members that have seen the studies might attempt to dissuade the use of such drugs in the oldest and most frail patients.

Source: Heart Disease Week of March 17, 2002