Scientists Higher mortality through the heart drug Digitalis

The treatment of cardiac patients with digitalis may involve a significantly higher risk than previously assumed. For example, a recent study by scientists at the University Hospital Frankfurt concludes that mortality in patients with heart problems is significantly increased by digitalis. Patients with heart failure or atrial fibrillation showed a significantly higher mortality rate when taking digitalis. Stefan Hohnloser and colleagues in the "European Heart Journal".

"There is conflicting evidence as to whether digitalis leads to increased mortality in patients with cardiac arrhythmias (atrial fibrillation) or heart pump weakness," the researchers write. However, in the largest metastatic study to date with the use of the active substance Digitalis, the researchers now come to the unequivocal conclusion that the groups of patients mentioned "actually have an increased mortality rate when treated with digitalis." This applies in particular to patients with atrial fibrillation.

Imminent serious side effects
Digitalis is extracted from the foxglove plant and has been used in medicine for centuries. Even today, the plant extract is used in patients with heart failure and an irregular heart rhythm due to atrial fibrillation. However, the dose range of the drug - ie the dosage at which digitalis is effective and harmless - according to the Frankfurt scientists very close. This narrow therapeutic window sometimes presents a significant problem when used. If the dosages are too high, there is a risk of serious side effects. In addition, numerous interactions of digitalis with other drugs are known. For this reason, "regular blood tests are recommended to determine digitalis blood concentration," report Hohnloser and colleagues.

21 percent higher risk of death
In the current meta-analysis, the researchers at the Frankfurt University Hospital took into account all published studies from 1993 to 2014. In the end, 19 relevant studies were identified in which data from a total of 326,426 patients (235,047 atrial fibrillation patients and 91,379 heart failure patients) were included the message of the University Hospital Frankfurt. The researchers conclude that "in the patients treated with digitalis, the mortality risk was increased by 21 percent compared to the patients who did not receive these drugs." Looking more closely at two groups of patients with atrial fibrillation or heart failure digitalis was accompanied by a 29 percent or 14 percent increase in risk.

Restraint offered in the application
Digitalis still has a place in the European and US therapy recommendations for the treatment of heart failure and atrial fibrillation, although these recommendations reflect only the hitherto highly unsatisfactory data on the use of digitalis, according to the Frankfurt scientists. There is a lack of "randomized controlled trials with digitalis to demonstrate the efficacy and safety of this medication"; so scornless and colleagues. Until these studies are available, they believe Digitalis should be used with great restraint. In addition, a careful monitoring of the patients, including determination of the plasma digitalis concentration, is necessary. "My personal opinion is that the time of digitalis therapy - especially as a heart rate-controlling drug for atrial fibrillation - is over," says Professor Hohnloser. However, this hypothesis must still be examined in corresponding studies.

Ongoing risk assessment process on digitalis
In Germany, six drugs are approved with the digitalis derivative digoxin, reports the news agency "dpa", citing the Federal Institute for Drugs and Medical Devices (BfArM). In addition, a preparation with the digitoxin variant is available, which also forms a digitalis derivative, Prof. Hohnloser is quoted by the news agency. A spokesman for the BfArM explained to the "dpa" that the European Medicines Agency (EMA) is currently checking the risks of the active substance and as soon as the results of this risk assessment procedure are known, the BfArM will inform about possible safety measures. However, quite a bit is already known about individual risks. For example, there is a potentially dangerous interaction between digoxin and the heart drug dronedarone. The technical information points out the danger. Of course, doctors should be aware of this risk and take it into account when treating their patients. Overall, the BfArM, according to the news agency "dpa" 20 suspected cases of interaction since 1978 reported, including one death.

Do not discontinue digitalis medications on your own
Independent withdrawal of the digitalis medication by the patients is urgently advised against despite possible risks, according to the "dpa", citing the German Cardiac Society. Stephan Willems from the Eppendorf University Hospital in Hamburg is quoted by the news agency with the statement that the person concerned should sit down with their doctor and check whether it makes sense to continue to take the digitalis preparations. There are quite different alternatives here. According to Willems, the current study should definitely be a food for thought - not only for the patients, but also for the doctors. With well-adjusted patients is not necessarily a change of the drug required, but "setting a new patient on digitalis is no longer useful today, one can say for sure," Willems is quoted by the "dpa". (Fp)

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