CHECKUP : NEWS, TIPS AND TRENDS ESTROGEN THERAPY AND BAD NEWS.

Women who are taking estrogen replacement therapy to relieve the hot flashes of menopause and to help forestall bone loss due to osteoporosis may be getting bad news when they don't need to, according to a new study.

The reason: Women taking ERT are more likely to get an incorrect reading on a mammogram than other women, according to the study, published in a recent issue of the Journal of the National Cancer Institute.

Researchers who examined 8,779 post-menopausal women ages 50 and older found that those taking ERT were 71 percent more likely to get a false positive reading - a reading that suggests cancer is present when it is not - than those not taking estrogen.

False positive readings can cost a woman and her family dearly, both in emotional worry and in having extensive, unnecessary and expensive tests done to confirm the reading, said the researchers, led by Dr. Mary B. Laya, acting assistant professor of medicine in the Women's Health Care Center at the University of Washington.

Women taking hormone therapy also appeared to be more likely to get a false negative reading - a failure to detect cancer where tumors existed - than women who did not take estrogen, according to the study.

This new finding in particular reinforces how important it is for women 50 and older - particularly those taking hormone replacement therapy - to have regular mammograms, said Robert A. Smith, senior director for detection and treatment at the American Cancer Society.

Heartfelt problem: People who feel persistently ``blue'' may be more likely to have a heart attack, a new study shows.

Previous studies have shown that depression can impede recovery after a heart attack.

But this research, published in the June 1 issue of Circulation, is among the first to show that depressive symptoms - including low self-esteem and low motivation - actually may facilitate its development.

In the study, spanning more than two decades, Danish researchers found that both men and women who scored high on an initial test measuring depressive symptoms were 70 percent more likely to have a heart attack, compared with those who did not report signs of depression.

And of the 730 Danish men and women followed, those who reported feeling depressed at the beginning of the study were 60 percent more likely to die from any disease, researchers reported.

Although exactly how feeling depressed can trigger the onset of disease is unknown, it may be that depressed people are more likely to engage in self-destructive habits such as smoking, speculated researchers led by John C. Barefoot, a psychologist and associate research professor at Duke University Medical Center in Durham, N.C.

Another reason that may account for the link between the two conditions is that depression stimulates the sympathetic nerves. When stimulated, these nerves tend to increase heart rate, tighten blood vessels and raise blood pressure - all of which are known risk factors for heart disease, the researchers wrote.