Medical errors are now the third-leading cause of death in the United States, claiming more than 250,000 deaths per year, according to a new study published Tuesday in the journal BMJ.

Only heart disease and cancer take more American lives, say the study’s authors. 

But even that stunning finding probably understates the true incidence of death due to medical error because U.S. death certificates do not provide a way of acknowledging such errors and because the estimate is based only on inpatient (hospital) deaths, say the study’s authors, Dr. Martin Makary, a professor of surgery, and Michael Daniel, a research fellow, at Johns Hopkins University in Baltimore, Md.

Even so, the new estimate of medical-error deaths is more than 100,000 higher than that presented in a much-publicized 1999 study by the Institute of Medicine (now the National Academies of Science, Engineering and Medicine) — a study that Makary and Daniel say was based on limited data and is now outdated.

How estimates were reached

Medical errors are defined in the new study as “an unintended act (either of omission or commission) or one that does not achieve its intended outcome, the failure of a planned action to be completed as intended (an error of execution), the use of a wrong plan to achieve an aim (an error of planning), or a deviation from the process of care that may or may not cause harm to the patient.”

As Makary and Daniel point out, many medical errors are nonconsequential, but some “can end the life of someone with a long life expectancy or accelerate an imminent death.” It was those lethal errors that the two researchers focused on.

For their study, Makary and Daniel examined four studies that examined medical death rate data from 2000 to 2008 — since the IOM study. Then, using hospital admission rates from 2013, they extrapolated that based on a total of 35,416,020 hospitalizations, 251,454 deaths resulted from a medical error.

That’s about 9.5 percent of all deaths each year in the U.S.

More Americans died of heart disease (611,105) and of cancer (584,881) in 2013, according to statistics from the Centers for Disease Control and Prevention (CDC).   

But if Makary and Daniel’s estimates are correct, medical errors shortened more lives than all other causes of death on the CDC list, including chronic respiratory disease (149,205), accidents (130,557), stroke and other cerebrovascular diseases (128,978), Alzheimer’s disease (84,767) and diabetes (56,979).

“Top-ranked causes of death as reported by the CDC inform our country’s research funding and public health priorities,” said Makary in a released statement. “Right now, cancer and heart disease get a ton of attention, but since medical errors don’t appear on the list, the problem doesn’t get the funding and attention it deserves.”

Strategies for improvement

This is not just a U.S. problem. “Medical error leading to patient death is under-recognized in many other countries, including the UK and Canada,” write Makary and Daniel.

Nor is it a problem that will ever go away completely. As the two researchers point out, “Human error is inevitable.”

Yet, as they also note, “although we cannot eliminate human error, we can better measure the problem to design safer systems mitigating its frequency, visibility, and consequences. 

Makary and Daniel suggest several strategies to reduce deaths from medical care.  Errors should be made more visible so that doctors, nurses and others are aware of their effects — and so that more safety nets can be put in place to prevent them, they say.  Furthermore, hospitals should undertake a rapid independent investigation into deaths to determine if human error was a possible contributor.

Such efforts are “an important prerequisite to creating a culture of learning from our mistakes, thereby advancing the science of safety and moving us closer towards creating learning health systems,” they stress. 

This transparency should be extended to death certificates, the researchers add. 

“Instead of simply requiring cause of death, death certificates could contain an extra field asking whether a preventable complication stemming from the patient’s medical care contributed to the death,” they write. “… When a medical error results in death, both the physiological cause of the death and the related problem with delivery of care should be captured.”

That data could then be shared with researchers to improve patient safety, both nationally and internationally — “in the same way as clinicians share research and innovation about coronary artery disease, melanoma, and influenza,” write Makary and Daniel.

“Sound scientific methods, beginning with an assessment of the problem, are critical to approaching any health threat to patients,” they conclude. “The problem of medical error should not be exempt from this scientific approach. More appropriate recognition of the role of medical error in patient death could heighten awareness and guide both collaborations and capital investments in research and prevention.”

FMI: You can read Makary and Daniel’s analysis on the BMJ website.