The new generation of antipsychotic drugs, used to treat conditions ranging from schizophrenia to anxiety, put patients at higher risk of sudden death due to cardiac arrest, says a new study.
Though the odds of a heart problem are low, and specialists insist the drugs are appropriate for certain patients, doctors, families and patients should still be cautious, said study lead author Wayne Ray, director of the Vanderbilt University School of Medicine's Division of Pharmacoepidemiology.
With all drugs, points out Health24's CyberShrink, Prof Michael Simpson, one has to balance the risks and benefits. "The risks of untreated, or inadequately treated psychotic illness are significant," says Simpson. "Some of these drugs can be very valuable but should only be used with caution and usually when alternatives are insufficient."
Ray concurs: "If they're being used for schizophrenia, consider a cardiology evaluation. If you're considering using them for bipolar disorder, think about using another alternative drug first."
And patients should rarely, if ever, take the drugs to treat other conditions, he said.
Drugs used for "off-label" uses
At issue are newer antipsychotic drugs - clozapine (Clozaril), quetiapine (Seroquel), olanzapine (Zyprexa) and risperidone (Risperdal). US health officials have approved these to treat schizophrenia and bipolar disorder, though doctors also prescribe them for so-called "off-label" conditions such as anxiety, attention deficit disorder in children and dementia in the elderly.
Simpson confirmed that all these drugs are frequently prescribed in South Africa.
"Zyprexa and Seroquel do seem to be used by some doctors rather too easily. The reason for using the drug must be serious and safer alternatives should have proved ineffective… I see no sense in using them for anxiety disorder, except perhaps in rare instances,” he said.
"For schizophrenics, they work pretty well. They're pretty much the only alternative," Ray said. But other drugs offer alternatives for bipolar patients, he said.
With regard to dementia, Simpson suggested these second generation antipsychotics might well be the only treatment that enables sufferers to live a life with any quality and independence. "For this reason they must remain available. There are no effective alternatives, and even partial alternatives have their own risks – and not providing such drugs in the dementing causes significant risks too."
Expanded on earlier research
For the new study, published in the New England Journal of Medicine, Ray and his colleagues expanded on earlier research that suggested the newer drugs disrupt the heart's rhythm. The researchers examined the medical records of 44 218 patients who used the older antipsychotic drugs and 46 089 patients who used the newer ones. All the patients lived in Tennessee and were recipients of Medicaid, the government-sponsored insurance program that serves low-income people.
The researchers also looked at the records of 186 600 people who didn't use antipsychotic drugs.
They found that users of the newer drugs were 2.26 times more likely to suffer from sudden cardiac death than those not on the medications. Those who used the older drugs were 1.99 times more likely to die versus those not taking the medications.
3-in-1 000 risk of sudden cardiac death
Patients who took the highest doses were at the highest risk. Overall, the patients had a three-in-1 000 risk of sudden cardiac death a year, Ray said.
The numbers may seem low, but they're significant, Ray said. "If I were talking to a friend or family member, I'd advise them to avoid [the drugs] if possible."
The drugs appear to cause problems by disrupting potassium in the heart, causing its electrical rhythm to fail, Ray said.
Dr Sebastian Schneeweiss, an associate professor of medicine and epidemiology at the Harvard School of Public Health, co-wrote an accompanying commentary in the journal. He said that, considering the risk and lack of evidence that the drugs are useful beyond limited cases, doctors should "sharply" reduce their use to treat conditions other than acute psychosis and schizophrenia.
- (Randy Dotinga/HealthDay News, Health24)
Antipsychotics can kill
Antipsychotics a death risk?