(Dave Murray/For The Washington Post)

Having a bad boss can make your work life a misery, but it can also make you sick, both physically and mentally, researchers say.

“The evidence is clear that the leadership qualities of ‘bad’ bosses over time exert a heavy toll on employees’ health,” says Jonathan D. Quick, an instructor in medicine at Harvard Medical School and a co-author of the book “Preventive Stress Management in Organizations.” “The evidence is also clear that despite the rationalizations some leaders may use to defend their stress-inducing, unsupportive style, such behavior by leaders does not contribute to improved individual performance or organizational productivity.”

Research has linked having a lousy boss to an increased risk of heart attack, Quick said. Chronic stress that can result when someone must deal daily with a bad boss has been linked to high blood pressure, sleep problems and anxiety and is also associated with several unhealthy behaviors such as smoking, excessive use of alcohol and overeating.

[Related: How to protect your health against a bad boss]

Difficult bosses can come in many forms, including hypercritical micromanagers, inept managers, bosses who push blame for problems onto others or hurl obscenities, and those who make unwanted sexual advances. But researchers say that whatever the type, when employees deal with a bad boss day in and day out, negative health effects often begin to pop up.

(Dave Murray/For The Washington Post)
A link to heart disease

One key study published in 2009 in Occupational & Environmental Medicine analyzed data on 3,122 men to see whether the leadership qualities of their managers were associated with a risk for fatal or nonfatal heart attack, angina and death due to heart disease.

Men who rated their managers as good (essentially meaning considerate, and providing information, feedback and sufficient control to employees) had at least a 20 percent lower risk of developing heart disease over a 10-year period than those who rated their managers as poor on such attributes. Although the study did not prove causality, the association became stronger the longer the employee stayed at the same workplace and was independent of other factors such as smoking and exercise.

Anna Nyberg, the lead author of the study and a researcher at the Stress Research Institute at Stockholm University, says there’s an important takeaway from the research: “The longer you have worked at a workplace, the better or worse the situation becomes. So if you are working under a boss who stresses you in a destructive manner, and your possibilities or chances to change the situation are limited, you should try to change jobs as soon as possible.”

Research also has linked the degree to which supervisors demonstrate fairness (such as giving timely feedback, including praise when warranted, and showing trust and respect) to employees’ blood pressure. A small 2003 study published in Occupational & Environmental Medicine found that workers’ blood pressure readings were significantly higher when they worked for supervisors they perceived unfavorably on such traits than when they worked for supervisors they viewed more favorably.

A more recent meta-analysis published in 2012 in the Journal of Applied Psychology looked at 279 studies to examine the associations between perceived unfairness and employee health; it found a link between unfairness and mental health complaints, such as depression, and physical ailments, such as sleep problems, high blood pressure and being overweight.

While changing jobs when faced with a bad boss is often the quickest way to restore your health, other approaches can help when quitting isn’t possible, says Richard O’Connor, a psychotherapist in New York and the author of “Undoing Perpetual Stress.” If there are people you trust within the workplace to talk to about the problem, for example, you may be reassured to learn that they are having similar conflicts with the same manager, he says. That by itself can reduce stress.

“One of the ways that bad bosses work is through splitting people,” O’Connor says. “They play favorites and develop a network of informers, so that you don’t trust anybody and you really do feel more isolated. You feel that there must be something wrong with me because everybody else seems to be getting along okay.”

Emily Wilson, a 25-year-old communications professional who lives and works in Washington, says she once had a micromanager boss who hovered over her and humiliated her in meetings by routinely dismissing her suggestions and commenting about errors she had made. Wilson says the anxiety she experienced at that job caused her to suffer panic attacks. “I felt like I couldn’t breathe, and I could barely talk,” she says. She left that job after five months and hasn’t had a panic attack since.

When Darryl Defilippi, who lives in Woodbridge, Va., was promoted to assistant manager of an automotive retail shop earlier in his career, his supervisor constantly pushed off his own responsibilities and didn’t provide any training. The job led to anxiety, the loss of a relationship and insomnia, says Defilippi, who is now 30. After realizing that other managers at that job were “giant balls of stress . . . they were all bald, overweight and some even had heart attacks,” Defilippi was able to get transferred about six months later to a different location and began working for a better manager. There his health issues cleared up within a couple of weeks.

Not surprisingly, problems with bosses are a common reason that people seek out mental health support, explains Larney R. Gump, a psychologist with a private practice in Washington.

Some people come in feeling unhappy, depressed or anxious, says Gump, who is also a professor of clinical psychology at George Washington University, and through talking about it, they realize that their bosses are part of the problem. Those patients could be dealing with “hostile, abrasive or mean bosses . . . or ones who are ineffective, passive or [who] don’t manage at all,” he explains.

People who have bad bosses often describe the situation as a living hell, says E. Kevin Kelloway, Canada Research Chair in Occupational Health Psychology at St. Mary’s University in Halifax, Nova Scotia. He was lead author of a 2010 review of studies about the effect of leaders on the psychological and physical well-being of their subordinates. “From the time you get out of bed, you’re dreading going to work.”

This produces a fight-or-flight response, which causes your body to pump out adrenaline and other stress hormones — just as it would if you were running from a tiger baring its teeth, Kelloway says. Your breathing quickens and your heart beats faster as your body prepares to spring into action. When this stress response goes on too long or occurs too often, it can take a toll on the body by destabilizing hormone levels and promoting other physiological changes that can increase the risk of chronic disease.

“If a tiger is chasing you, then it’s appropriate to run away,” he explains. “But you don’t get to run away from your boss.”

Shannonhouse is a writer who lives in Connecticut.