Women age 60 years or less are the most likely patients to become depressed during hospitalization for an acute myocardial infarction, according to an article in the April 24 issue of the Archives of Internal Medicine.

Depression is common in patients with cardiovascular disease, including acute myocardial infarction, according to background information in the article. Depressed patients with acute myocardial infarction are more likely to be hospitalized and die of heart problems and tend to have worse health and higher health care costs than patients who are not depressed. Identifying patients who are at higher risk for depression could help physicians screen and treat those at highest risk.

Susmita Mallik, MD, MPH, Emory University School of Medicine, Atlanta, and colleagues assessed the prevalence of depression in 2,498 patients who were hospitalized with acute myocardial infarction between January 2003 and June 2004 at one of 19 study sites across the United States.

The 814 women and 1,684 men were interviewed during hospitalization and asked how often they experienced each of nine symptoms of depression. For each patient, researchers compiled an overall depression score between 0 and 27 by adding points for each answer?from zero for each symptom that bothered the patient “not at all” to three for each that he or she experienced “nearly every day.” Individuals with a score of 10 or higher were classified as depressed. Participants’ medical records also were reviewed.

Patients were interviewed an average of 2.9 days after they arrived at the hospital. About 22 percent of all participants were depressed, and those who were depressed had more associated illnesses, were in poorer health and were more likely to have a history of heart problems and diabetes than those who were not. Women and younger patients (age 60 years or younger) were more likely to be depressed than men and older patients, with younger women at highest risk.

The prevalence of depression was 40 percent in women age 60 years or younger, 21 percent in women older than 60, 22 percent in men 60 or younger, and 15 percent in men older than 60. In additional analysis in which other factors were considered, the odds of depression were three times higher for women age 60 years and younger than for men older than age 60 years.

Researchers are not sure why younger women are most likely to be depressed after heart attack, but the authors suggest that hormones and social pressures may contribute to their increased risk. “Differential sex roles and exposure to social and environmental stressors, such as poverty, lower level of education, responsibilities both at work and home, single parenthood and caring for children and aging parents, could theoretically contribute to a higher preponderance of depression in younger women, who may have greater exposure to these stressors compared with other groups,” they wrote.

These findings also suggest that depression may be part of the reason that younger women are more likely than younger men to have complications or die after myocardial infarction, although further study is needed to evaluate this connection. Either way, younger women may benefit from more aggressive screening and treatment of depression after myocardial infarction, the authors conclude.