Walking as a daily exercise helps reduce the risk of heart attack in elderly men, especially if they walk more than a mile and a half a day, a Hawaiian study suggests.

The findings, combined with other evidence of the value of regular exercise, hint that "important health benefits could be derived by encouraging the elderly to walk," researchers concluded.

They studied more than 2,600 men aged 71 to 93. All were free of obvious heart disease and physically capable of walking for at least an hour a day.

During the study, 109 of the men had heart attacks. But heart attacks were least common in the group that walked the most. The rate of heart attack among those who walked at least 1.5 miles a day was about half that found in the other groups. The findings were published last week in the American Heart Association journal Circulation.

"From a public health standpoint, the finding that exercise that is neither strenuous nor prolonged can benefit an individual at any age is encouraging," wrote two specialists from the University of Texas Southwestern Medical Center in Dallas in an accompanying editorial.

Researchers noted that walking "may simply reflect an overall healthy lifestyle," including good nutrition and an active life. Whether walking can reduce the risk of coronary heart disease when it is begun late in life by previously sedentary people is a question still to be answered, they said.

The study, based on a large investigation of Hawaiian men of Japanese ancestry, was conducted by researchers from the University of Virginia, the University of Minnesota and the University of Hawaii.

--Don Colburn


Black and white youths differ significantly in their perceptions of fatness and desired weight, according to an analysis of data from the National Health and Nutrition Examination Survey (NHANES) III. Boys also view body weight differently than girls.

Richard S. Strauss, a pediatric gastroenterologist at the University of Medicine and Dentistry of New Jersey, examined data including heights and weights of 1,932 youths between the ages of 12 and 16. He found that the participants' reports of whether they considered themselves overweight or not were poorly correlated with medical definitions of overweight or obesity and were strongly linked to sex and race.

Fifty-two percent of girls who believed they were too fat were of normal weight, compared to only 25 percent of boys. White girls were much more likely to consider themselves overweight than were black girls, black boys or white boys, noted Strauss in the July issue of the Archives of Pediatric and Adolescent Medicine.

Strauss found that girls, especially white girls, were more than twice as likely as boys to want to weigh less, while boys of the same age tended to want to weigh more.

"There is no doubt that increasing emphasis on thinness by television, advertising and marketing campaigns has a profound effect on the desire to be thinner, especially among females," he wrote. "Most alarmingly, girls as young as 5 or 6 years old already express fear of gaining weight."

Strauss also cited racial differences in perceptions of excess weight. "In general African American women do not perceive overweight as unhealthy or unattractive" and report "more positive feelings about their bodies and less concern about body weight than white women. In addition, black men and women are more accepting of larger figures," he concluded.

--Sandra G. Boodman


Two drugs have shown some success in relieving depression by targeting a different brain chemical than does the popular drug Prozac, according to presentations at the annual American Psychiatric Association meeting here in May.

Prozac, first approved in 1988, is part of a class of drugs called selective serotonin reuptake inhibitors (SSRIs) that affect the way the brain uses the chemical serotonin. One of the new drugs, reboxetine, is a selective norepinephrine reuptake inhibitor (NRI). It affects the compound norepinephrine, which helps the brain cells transmit messages. The second new drug, venlafaxine, is both an NRI and an SSRI.

"We think the norepinephrine pathway may have a critical role in depression," said one of the study's researchers, Dennis S. Charney, deputy chairman of academic and scientific affairs and professor of psychiatry at Yale University School of Medicine in New Haven, Conn.

In a study of 549 patients with major depressive disorder in Europe, Latin America and Australia, participants received reboxetine, Prozac or a placebo. At the end of eight weeks, participants were assessed using a standard self-evaluation psychiatric test. Those who had received reboxetine showed a 10.3 percent improvement, compared with 7.6 percent for the Prozac group and 3.4 percent for the placebo group.

Reboxetine has been available under the brand name Edronax in 10 European countries since 1997. Its manufacturer, Pharmacia & Upjohn, filed for permission to market it in the United States in April 1998; that application is under review by the FDA.

In the second study, 895 participants received venlafaxine, marketed as Effexor by Wyeth-Ayerst Laboratories, and 769 patients were treated with SSRIs. After eight weeks, 43 percent of the venlafaxine users reported that their symptoms had disappeared, compared with 33 percent of the SSRI users.

"It's very rare to see one of the newer antidepressants beat out another in a clinical trial," said Stephen Stahl, professor of psychiatry at the University of California at San Diego, who presented the findings at the APA meeting. "But the test has broader implications in that it tells me that synergy--the use of several drugs working side by side--works in psychiatry."

--Pamela Gerhardt