Drug Overdose Linked To More Heart Deaths Than Previously Believed: Study

The findings of a new study suggest that drug overdoses may play a bigger role in sudden cardiac death than previously believed, but the connections often go unreported. 

Researchers at the University of California San Francisco found that about 40% of deaths classified a sudden cardiac deaths (SCDs) were actually incorrectly categorized, and that one of the top actual causes of those types of deaths was drug overdose. The findings were published last week by the medical journal Circulation.

More than 90% of sudden cardiac deaths occur in non-medical settings, and in most cases, there are no autopsies performed, according to the researchers. Therefore the cause of death is often assumed.

In this latest study, researchers looked at all incident deaths attributed to out-of-hospital cardiac arrest for individuals from 18 to 90 years old in San Francisco County from February 1, 2011, through March 1, 2014. Researchers looked at autopsy data, toxicology, histology and other records. They compared that data to the World Health Organization’s criteria for sudden cardiac death.

The findings indicate that 57% of the deaths involved no cardiac history. The researchers found that while the leading cause of death was coronary disease, which is to be expected, that was only 32% of the cases. Drug overdose came in second at 13.5%, followed by cardiomyopathy, cardiac hypertrophy and neurological causes.

According to the study, more than half of the drug overdose deaths involved lethal levels of opioids.

“Because none of the WHO-defined SCDs found to be due to occult overdose had evidence or suspicion of drug use at the scene and all had a primary EMS impression of cardiac arrest, overdoses and other metabolic emergencies may be underrecognized as underlying causes of sudden death,” the researchers reported.

The findings suggest that the death toll from drug overdoses, particularly opioids, is significantly higher than currently assumed.

This study appears to confirm previous research indicating opioid problems are widely under reported.

Even under current estimates, the opioid crisis has worsened in recent years, as overdose deaths continue to rise, accounting for two-thirds of drug overdose deaths in the U.S.

The U.S. Centers for Disease Control and Prevention reports the opioid crisis hit an all time high, with overdose deaths increasing nearly 140%. The FDA recently announced plans to address the opioid crisis, including  a focus on pain management to reduce new addictions, non-drug treatments, new opioid formulations, and prescriber programs.

Many critics point to doctor prescribing habits as a major factor in the crisis. A recent study indicated that nearly half of all patient who are given opioids don’t actually need them for pain relief.