A study conducted by City College of New York psychology Professor Irvin Schonfeld in the Colin Powell School for Civic and Global Leadership connects burnout and depression, according to PsyPost.

Over 5,500 school teachers were evaluated for burnout. Of those identified as burned out, 90 percent also met diagnostic standards for depression. Atypical depression was identified in 63 percent of those participants with major depression.

Symptoms of atypical depression are listed by the Mayo Clinic as:

• "Depression that temporarily lifts when you're cheered up by good news or positive events but returns later;
• "Increased appetite with unintentional weight gain;
• "Increased desire to sleep, usually more than 10 hours a day;
• "Heavy, leaden feeling in your arms and legs that lasts an hour or more in a day;
• "Trouble maintaining long-lasting relationships because of sensitivity to rejection or criticism, which affects your relationships, social life or job."

"The study suggests that the burnout- depression overlap has been largely underestimated," said Schonfeld, according to PsyPost. "Atypical depression may account for a substantial part of this overlap. Overall, our findings point to depressive symptoms and depressive disorders as central concerns in the management of burnout. The clinical research on treatments for depression offers solutions that may help workers identified as burned out."

"Is Burnout a Depressive Disorder? A Reexamination with Special Focus on Atypical Depression," was published in "International Journal of Stress Management."