WEDNESDAY, April 9 (HealthDay News) -- The same 10 gene mutations responsible for cardiac hypertrophy (thickening of the heart muscle) in adults are also associated with many cases of this rare but life-threatening condition in children, says a U.S. study.

The mutations even showed up in children who had no family history of the condition, the researchers noted.

Currently, little is known about the causes of cardiac hypertrophy in children, so no diagnostic tests for children have been developed. The findings of this study suggest that the same genetic test designed for adults can be used in children, which may help increase knowledge about the condition and lead to new kinds of treatments, said study authors Christine and Jonathan Seidman, professors at Harvard Medical School in Boston.

About one in 100,000 children develops cardiac hypertrophy, which can lead to sudden death. About 3 percent to 4 percent of adults have the condition. Most of the genes implicated in cardiac hypertrophy encode sarcomere proteins, which help the heart tighten and relax to pump blood.

"Cardiac hypertrophy increases your risk of all types of negative cardiovascular outcomes, including heart failure and sudden death. Although the condition is rare in children, the prognosis is even worse. Kids with cardiac hypertrophy are often candidates for transplantation," Jonathan Seidman said in a prepared statement.

"Labs have done work on the genetic underpinnings of cardiac hypertrophy in adults, but few thought that the research applied to children. For years, doctors assumed the two conditions were clinically distinct," Christine Seidman, who is also a member of the HMS-Partners HealthCare Center for Genetics and Genomics, said in a prepared statement.

In this study, the Seidmans and their colleagues from Children's Hospital Boston and Baylor College of Medicine analyzed DNA from 84 children diagnosed with cardiac hypertrophy before age 15. Of those, only 33 had family histories of the condition.

The researchers identified mutations in the 10 suspect genes in 25 of the 51 children without family histories of cardiac hypertrophy and in 21 of the 33 with family histories.

"I think it's remarkable that we found mutations in nearly 50 percent of the kids who don't have family histories," Christine Seidman said.

The researchers also analyzed DNA from 11 pairs of parents and found that in seven of those couples, one parent had the same mutation as his or her child. The parents with these mutations believed their hearts were healthy, but echocardiograms revealed thickening of the muscle in some cases.

"We still don't know why the children presented symptoms so much earlier than their parents. We suspect that other genes must influence the disease presentation," Jonathan Seidman said.

Further genetic testing of children with cardiac hypertrophy and their parents may explain this and help doctors select appropriate treatments, the researchers said.

The study was published online April 9 in the New England Journal of Medicine.

More information

The MedlinePlus Medical Encyclopedia has information about hypertrophic cardiomyopathy.

TUESDAY, April 8 (HealthDay News) -- Exercise does a body good -- two bodies when the one exercising is a pregnant woman.

A new study shows that when a mom-to-be works out, her fetus reaps cardiac benefits. The benefits show up as lower fetal heart rates, according to the finding to be presented this week at the Experimental Biology 2008 annual meeting in San Diego.

"This study suggests that a mother who exercises may not only be imparting health benefits to her own heart, but to her developing baby's heart as well. As a result of this pilot study, we plan to continue the study to include more pregnant women," study co-author Linda E. May, of the Department of Anatomy at Kansas City University of Medicine and Biosciences, said in a prepared statement.

Ten women participated in the study, half of whom were exercisers and the other half who weren't. Fetal movements such as breathing, body and mouth movements were monitored and recorded from 24 weeks into pregnancy to term.

The researchers found significantly lower heart rates among fetuses that had been exposed to maternal exercise throughout the study period. The heart rates among the fetuses not exposed to exercise were higher, regardless of the fetal activity or the gestational age.

More information

The U.S. Department of Health and Human Services has more about prenatal care.

MONDAY, April 7 (HealthDay News) -- Schools that serve healthier foods, offer nutrition education and reward students for nutritious eating habits can make a major difference in preventing childhood obesity, according to a Temple University study.

Schools that implemented such a multifaceted nutrition program reduced the number of overweight children by 50 percent, the study, published in the April issue of Pediatrics, found.

"The increasing prevalence and serious consequences of childhood obesity have pushed us to find solutions that go beyond the clinic and reach greater numbers of children," lead author Gary Foster, director of Temple's Center for Obesity Research and Education, said in a prepared statement. "We focused on school, because children spend most of their lives there and eat at least one if not two meals there."

In the study, five Philadelphia schools introduced a School Nutrition Policy Initiative that included:

• Eliminating less healthy snacks and sodas available at school or replacing them with better options, such as water, low-fat milk or 100 percent fruit juice.
• Training teachers to teach about nutrition and giving students 50 hours of nutrition education during the year.
• Rewarding kids with raffle tickets to win prizes when they practice healthy snacking.
• Encouraging parents and students to purchase healthy snacks outside of school, and challenging the kids to eat better and be more physically active.

Over the course of two years, researchers followed students in grades 4 through 6 at these schools and five control schools, measuring the weight, height and physical activity of all 1,349 study before and after the study period.

Only 7.5 percent of students in schools with the new nutrition policy became overweight, compared with 15 percent of student who became overweight in the control schools. The nutrition policy appeared even more effective in preventing black students from becoming overweight when comparing the two groups of schools.

Despite the success, researchers expressed concerns that some students in School Nutrition Policy Initiative schools still gained weight. They suggested that stronger or additional interventions are needed, such as increasing physical education time, instituting more aggressive nutrition policies, and finding ways to change the nutrition environment outside of schools.

The researchers also recommend that prevention programs begin even earlier than fourth grade, as the prevalence of overweight children in grades 4 through 6 is already at 41.7 percent.

More information

The U.S. Department of Health and Human Services has more about childhood obesity.

TUESDAY, March 11 (HealthDay News) -- More than 3 million teenaged girls have at least one sexually transmitted disease (STD), a new government study suggests.

The most severely affected are African-American teens. In fact, 48 percent of African-American teenaged girls have an STD, compared with 20 percent of white teenaged girls.

"What we found is alarming," Dr. Sara Forhan, from the U.S. Centers for Disease Control and Prevention, said during a teleconference Tuesday. "One in four female adolescents in the U.S. has at least one of the four most common STDs that affects women."

"These numbers translate into 3.2 million young women nationwide who are infected with an STD," Forhan said. "This means that far too many young women are at risk of the serious health effects of untreated STDs, including infertility and cervical cancer."

These common STDs include human papillomavirus (HPV), chlamydia, herpes simplex virus and trichomoniasis, Forhan said.

Forhan announced the results as part of the CDC's 2008 National STD Prevention Conference, in Chicago.

"These findings are really giving us a lot of pause about how we provide care to adolescent girls who are sexually active," said Dr. Elizabeth Alderman, an adolescent medicine specialist at Children's Hospital at Montefiore in New York City and chairperson of the Executive Committee of the Section of Adolescent Health of the American Academy of Pediatrics. "The numbers are really astonishing."

Forhan noted that most of the burden of STDs falls on young African-American women. "Among African-American teenagers, about one in two were affected compared to one in five white teens," she said.

In terms of the racial disparity, "it's what we've always seen, which is very unfortunate," Alderman said.

In the study, Forhan's team collected data on 838 girls aged 14 to 19 who took part in the 2003-2004 National Health and Nutrition Examination Survey. The study did not include syphilis, gonorrhea or HIV, as earlier studies found very low prevalence of these diseases in this age group.

HPV and chlamydia are the most common STDs found among teenage girls, Forhan said. "Almost one in five overall had a strain of HPV associated with cervical cancer or genital warts," she said.

"We need to be screening adolescent girls who are sexually active and providing them with HPV vaccine," Alderman said. "The recommendations are to screen sexually active girls, but many girls don't disclose to their health-care provider that they are sexually active, even when asked," she said.

As for chlamydia, 4 percent of teenaged girls had this STD, Forhan said. "The majority of chlamydia infections do not have symptoms. If left untreated, it can lead to pelvic inflammatory disease, which leaves these young women at risk for atopic pregnancy, chronic pelvic pain or infertility," she said.

In addition, the study found that 2.9 percent of young women had trichomoniasis, and 2 percent were infected with genital herpes, Forhan said.

According to Forhan, about 50 percent of the teens reported having sex, and the prevalence of STDs in this group was 40 percent. "Even for young women with only one reported lifetime sexual partner, one in five had an STD," she noted.

"If you choose to be sexually active, you need to protect yourself and be screened for these infections," Alderman said. "And all girls between the ages of 11 and 26 should get vaccinated for HPV."

Among women with an STD, 15 percent had more than one infection, Forhan added.

"These data provide a clearest picture to date of the overall burden of STDs in adolescent women in the United States," Forhan said. "The study also underscores the importance of addressing racial disparities in STD rates among young women."

Race itself is not a risk factor for STDs, Forhan said. However, factors such as limited access to health care, poverty, community prevalence of STDs, and misperceptions about individual risk are some of the reasons that STD rates are particularly high among African-Americans, she said.

More information

For more on STDs, visit the U.S. Centers for Disease Control and Prevention.