Depression, stress, loneliness, a positive (or negative) outlook on life, and other psychosocial factors extend beyond affecting mood and reach into the heart. How you think, feel, and behave can affect heart disease for better or for worse, reports the June issue of the Harvard Heart Letter.

In terms of their contribution to heart attacks, psychosocial factors are on a par with smoking, high blood pressure, obesity, and cholesterol problems. How do emotions, behaviors, or social situations promote heart disease or make it worse? No one really knows, says the Harvard Heart Letter, which will be exploring the mind-heart connection in its next two issues as well. But there are plenty of theories.

Stress hormones top the list. They constrict blood vessels, speed up the heartbeat, and make the heart and blood vessels especially reactive to further stress. Psychosocial factors have also been linked with factors that signal increased inflammation, which plays an important role in artery-clogging atherosclerosis. Psychosocial factors could also make people more or less likely to pick up habits that tip them toward heart disease or away from it.

The connection between psychosocial factors and heart disease is so strong that today’s cardiologists should ask their patients about moods, stress, and support, says the Harvard Heart Letter. Most don’t, at least not yet. If yours doesn’t, it’s worth bringing up these issues yourself. Because physicians get little training in this area, though, don’t be surprised if yours is uncomfortable discussing psychosocial factors, or doesn't know how to help. If that’s the case, don’t hesitate to ask for a referral to a mental health professional.