Concerns about burnout among doctors are growing as new research is beginning to quantify the dangers and costs of the problem.

In the past few years, researchers have found that 54 percent of doctors report feeling burned out. Doctors experiencing burnout are twice as likely to log major medical errors. The suicide rate among physicians is twice that of the general population and one of the highest among all professions.

A study published Friday shows that as medical residents’ symptoms of burnout increase, they become more prone to racial bias.

“It’s becoming clearer with each study just how big of a problem this is,” said Liselotte Dyrbye, a researcher at the Mayo Clinic, who wrote Friday’s study on racial bias and several other studies on the problem.

Doctors are especially prone to burnout, experts say, because of the workload, pressure and chaos under which they often operate. Doctors say their work has become increasingly burdened with bureaucratic work because of cumbersome electronic records and what they call “defensive documentation” to guard against malpractice lawsuits.

Symptoms of burnout among physicians include emotional exhaustion, cynicism, loss of enthusiasm and joy in their work, and increasing detachment from their patients and their ailments. Burnout has been linked to higher rates of depression, substance abuse and suicide.

Most research to date has focused on problems such as increased risk of errors or doctors leaving the profession. Its effect on doctors’ biases has not been previously been studied in depth.

“No doctor wants to think implicit or explicit bias do play a factor, but we know that for anyone emotions impact behavior and decision. And doctors are not exempt from that,” Dyrbye said.

The medical community is increasingly recognizing that doctors’ biases — based on race, gender, obesity or other factors — can harm patients’ health.

“When a woman goes into the hospital with chest pain, for example, there are concerns about whether her pain is taken as seriously as a man’s. Whether doctors are going to miss a heart attack because they interpret it as a possible panic attack,” said Vineet Arora, a doctor and medical researcher at the University of Chicago, who was not involved in the study but has studied how to improve medical students’ training.

African American patients are routinely undertreated for their pain compared with white patients, for example, with doctors more hesitant to prescribe black patients pain medications.

African American women are three to four times more likely to die of pregnancy and birth-related complications than white women — a disparity that received more attention when Serena Williams and Beyoncé talked about their own life-threatening experiences.

Friday’s racial bias study — published in the American Medical Association’s JAMA Network Open — measured self-reported symptoms of burnout among nonblack physicians during their second and third years of residency, an intensive training phase when doctors begin practicing medicine under supervision and learn a specialized field.

The researchers administered tests for explicit bias by asking residents to rate their feelings toward black or white people on a scale from cold and unfavorable to warm and favorable. The researchers tested implicit bias by asking residents to sort pictures of people of different races along with words like “beautiful,” “cheerful,” “failure,” “scorn” and measuring how quickly they linked favorable traits to black or white faces.

Residents with more symptoms of burnout had higher scores on the measures of explicit and implicit racial bias. The study also found that as burnout decreased in some residents over time, their explicit racial bias also decreased.

While the study suggests a relationship between burnout and bias, it did not establish causation. “You can’t say from the work whether one causes the other,” said Arora, who reviewed the study. “The assumption is that burnout weakens decision-making and susceptibility to bias. But it could go the other way, too. If you have underlying bias, maybe you’re more prone to burnout because you’re caring for patients of color when you don’t want to be.”

Aside from impairing doctors’ ability to care for patients properly, burnout is expensive. A study published last month in the Annals of Internal Medicine provided the most comprehensive estimate to date of how much burnout is costing the industry. The authors, including researchers from Harvard Business School, the National University of Singapore, Stanford University, the American Medical Association and the Mayo Clinic, analyzed data from previous surveys on doctor burnout in the United States.

The researchers concluded that burnout is costing the medical system $4.6 billion a year. Some of this cost comes from burnout prompting doctors to reduce their hours, quit their jobs or leave medicine altogether. With each doctor affected by burnout, the estimated average cost to the medical industry in America is roughly $7,600 per doctor.

Those numbers don’t include costs from increased medical errors, malpractice lawsuits, and other doctors’ having to pick up the work of those who are burned out.

“It makes a compelling economic and business case for considering changes to the system,” said Joel Goh, a researcher at National University of Singapore and co-author of the cost study.