Health briefs

Compiled from Times wires

© St. Petersburg Times, published April 15, 2001

Study looks at effects of men's biological clocks

Men, take note: you, too, have a biological clock.

True, it does not tick toward the absolute deadline that ends women's child-bearing years. As notables like Tony Randall, Yasser Arafat, George Plimpton, Anthony Quinn, Clint Eastwood, Strom Thurmond and others have demonstrated, men can father babies no matter how old they get.

But a growing body of evidence shows that the fruit of aging loins is burdened with increased risk of a wide variety of gene-influenced illnesses. A study released last week raised the possibility that some cases of schizophrenia fall into that category.

The study found that older fathers are more likely to have children with schizophrenia. Fathers older than 50 have three times the risk of having a child who develops schizophrenia as fathers younger than 25, the study found. Earlier studies linked advanced paternal age to a variety of conditions, including the most common type of dwarfism, neural tube defects, nervous system cancer and prostate cancer.

Dr. Dolores Malaspina, a researcher at Columbia University and the lead author of the schizophrenia study, said that scientists have been seeing signs of a male biological clock for some time. "While scientists have known for years that older fathers are a major source of gene mutations," she said, "the public doesn't seem to have absorbed it, which may have something to do with a culture that sees older fathers as triumphantly virile."

As research continues, her team suggests it might be that the father's sperm will turn out to play as big a part in children's genetic problems as the mother's eggs.

While women are born with all the eggs they will have, the cells that become sperm divide and reproduce throughout a man's life -- with each division introducing a slight risk of error in the genetic material the sperm passes on to the children.

But the impulse to assess reproductive health by looking solely at the mother is a widespread one. In industry, efforts to keep women out of certain workplaces with dangerous substances have been turned back only with findings that the same substances can harm sperm -- so the better approach is to create an environment that will be safe for men and women.

While the club of biological clock watchers is not a happy one, some women say there is a certain satisfaction in welcoming male members.

"It's not a totally free ride for men," Pollitt said, "and that seems fair, that both men and women have lots to think about."

Mothers' influence linked to boys' aggression

Boys who are likely to become violent teens can be identified as early as kindergarten by their aggressive behavior, which accelerates as they grow, shows a study in the April issue of the Archives of General Psychiatry.

While most boys in the study group outgrew their aggressive tendencies, a small percentage had worsened by their teen years. What those boys had in common were poor, under-educated mothers who gave birth as teenagers.

"Our interpretation is that child-rearing skills are at a premium when you have a difficult child," said Daniel Nagin, a professor of public policy at Carnegie Mellon University. "On average, these mothers are at greater risk to lack skills to effectively parent a difficult child."

Nagin said the results will be beneficial for early intervention programs designed to turn the boys around and help at-risk mothers.

"Helping children learn to control their violent impulses can yield big returns not only to the child, but for society, and we should be doing more of that," Nagin said.

Nagin and co-author Richard Tremblay of the University of Montreal began tracking 1,037 high-risk, 6-year-olds in 1984 in Montreal to identify parental and child characteristics linked to aggression.

The researchers found the most powerful predictor of violence in adolescence was a high level of hyperactivity and oppositional behavior in kindergarten, as assessed by the teacher and parents.

Oppositional behavior was defined as not sharing, blaming others, being inconsiderate, irritable and disobedient. Hyperactivity was defined as being squirmy, fidgety and unable to keep still.

Aggressive fathers were not a factor in predicting violent behavior in teenagers, perhaps because they did not spend as much time with the child as did the mother, Nagin said.

Fast-evolving bacteria resists even newest drugs

CHICAGO -- Five Chicago patients have caught some of the first recorded infections from a strain of bacteria that has evolved so quickly it can overcome even the newest antibiotic, a study published Saturday says.

Doctors had counted on new drugs to provide a fresh arsenal in the fight against super-bugs that have grown resistant to older antibiotics. But the new research, published Saturday in the British journal The Lancet, shows that such dangerous bacteria have fashioned some resistance to the drugs.

The enterococcus germ, which affects mostly people recovering from transplants or severe illnesses, struck the five patients in Chicago hospitals during the last three months of 2000.

After other drugs failed, all five received the synthetic antibiotic Zyvox, which was approved for use last April. Some scientists had thought it would be especially difficult for bacteria to evade Zyvox because it attacks germs differently than most other drugs.

Although the antibiotic worked for most patients, researchers at the University of Illinois at Chicago Medical College found the bacteria grew resistant in these five, leaving them with little defense against infection.

The antibiotic still is extremely useful, experts said, since drug resistance has been confirmed in only a small number of patients. But Levy said the findings show the urgent need for more antibiotics to combat the advance of bacteria that are resistant to multiple drugs.

Of the five patients who developed Zyvox-resistant infections, two died. But Quinn said those patients suffered from severe illnesses and did not undergo autopsies, making it difficult to pinpoint their infections as the cause of death.

The emergence of some resistance does not mean that more patients will develop resistance over time. Some experts are hopeful that such trends can be reversed. The makers of Zyvox stress that the drug is meant only for cases where other antibiotics have failed -- making it less likely that overuse will lead to more resistance.

Even older drugs might be rehabilitated, said Levy of Tufts. By developing more antibiotics and cutting down on overuse of old drugs, common resistant bacterial strains might begin to fade.

Hormone therapy may not prevent osteoporosis

Hormone replacement therapy has taken its lumps in recent years, as two major studies have questioned whether it prevents heart disease in older women. A new study of estrogen supplements has failed to show that it prevents bone fractures and osteoporosis.

But the lead author, University of Pittsburgh epidemiologist Jane Cauley, said this latest study was hardly the last word on the subject. The findings were gleaned from a study that was designed primarily to see if hormone replacement prevented heart disease, she noted; the results might have been different if the women in the study had osteoporosis, rather than heart disease.

The study is, however, one of the few randomized clinical trials to test the effectiveness of hormone replacement on osteoporosis. The findings are being reported in the current issue of the American Journal of Medicine.

The research was performed as part of the Heart Estrogen/Progestin Replacement Study, or HERS, which enrolled more than 2,700 postmenopausal women in Pittsburgh and several other cities in the mid 1990s. About half were put on hormone replacement therapy and half weren't.

In the primary analysis, reported several years ago, investigators concluded that estrogen supplements did not protect women from further heart attacks.

When Cauley and colleagues from four other institutions looked at bone fractures in this same group of women, they found that after a little more than four years of follow-up about the same number of women on hormone replacement suffered bone fractures as did the women in the placebo -- 138 vs. 148.

A number of factors might explain this lack of benefit, Cauley said. It might take more than four years of hormone replacement therapy before women see benefits. They might also benefit if they started taking estrogen at a younger age; women in the HERS trial were an average of 18 years beyond menopause.

Cauley emphasized that women who are on hormone replacement therapy for osteoporosis should not abandon the therapy based on these latest findings.

A clearer picture should emerge in 2005, when results are expected from a larger study, the Women's Health Initiative.

Study disputes effect of 'smart drug' on Down's

CHICAGO -- One of the first studies of a so-called "smart drug" for Down's syndrome suggests it does not boost children's intellectual ability, despite testimonials on television and the Internet.

The drug, called piracetam, had side effects such as aggression, irritability and poor sleep in some of the youngsters.

Piracetam, though legal, is not approved for use in the United States.

"We did not identify even a single case that would suggest the possibility that piracetam therapy generally improved cognition," researchers said in the study, which appears in April's Archives of Pediatrics & Adolescent Medicine.

The study of 18 children ages 6 through 12 found no significant difference in mental function between those who took the drug and those who were given placebo pills.

Each child got four months of piracetam and four months of placebos.

Though parents of 11 children thought they seemed brighter or more focused on piracetam, intelligence tests showed no improvement compared with the placebo.

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