Experts have long thought that depression could be bad for your heart. A new study demonstrates just how dangerous it can be. Brenda Penninx, a gerontologist ( 老年病学家 ) at Wake Forest University, North Caroline, and her colleagues followed 2847 people over the age of 55-both with and without heart disease -- for four years in order to trace the effects of depression. In the end, they found that people with major depression were at least three times as likely to die of heart disease as patients who weren't depressed. Even subjects with mild depression experienced a fatality rate that was 50 percent higher than normal. Brenda Penninx isn't sure exactly what the connection between heart disease and depression is, but since depression can raise stress, and stress triggers an outpouring of the hormone cortisol( 荷尔蒙 ), and this could cause heart rate and blood pressure to rise. Other factors could also play a part: Depressed people are less likely to do physical exercise or eat right than those who do not suffer from the malady. "Depression deserves a lot more attention that it usually gets", Penninx warns. "It's a huge risk factor, so it's really crucial to take care of your emotions."