HEALTH AND WELLNESS

NEW YORK (Reuters Health) - People with mild cognitive impairment appear to have a lower risk of progressing to full blown dementia than previously thought, according to a new report.

Mild cognitive impairment is a transitional stage between normal brain function and dementia/Alzheimer's disease.

It's estimated that up to 15 percent of people with mild cognitive impairment go on to develop dementia, Dr. Alex J. Mitchell, of the University of Leicester, and Dr. M. Shiri-Feshki, of Nottinghamshire Healthcare NHS Trust, note in a report in the journal Acta Psychiatrica Scandinavica.

However, based on pooled data from 41 published studies they analyzed, the proportion of patients with mild memory problems who progress to full dementia is 10 percent per year in high-risk groups and 5 percent per year in low-risk groups.

"Moreover, only a minority (20 to 40 percent) of people developed dementia even after extended follow-up, and the risk appeared to reduce slightly with time," Mitchell noted in a university statement.

Mild cognitive impairment can no longer be assumed to always be a simple transitional state between normal aging and dementia," the researchers conclude.

SOURCE: Acta Psychiatrica Scandinavica, April 2009.

Copyright © 2009 Reuters Limited.

NEW YORK (Reuters Health) - Women who conceive in the spring or summer may run a higher risk of having a baby with a birth defect -- and pesticide exposure might help explain why, a new study suggests.

Using government data on U.S. births between 1996 and 2002, researchers found that birth defect rates were highest among women who'd conceived between April and July.

During those same months, surface-water concentrations of pesticides and other agricultural chemicals generally increased based on government water-quality assessments.

The findings, reported in the journal Acta Pediatrica, point to correlations between pesticide levels and birth defects, but do not prove a cause-and-effect relationship.

However, some of the chemicals tracked in the study, such as the weed killer atrazine, are suspected of causing harm to developing embryos, the researchers point out.

"While our study didn't prove a cause and effect link, the fact that birth defects and pesticides in surface water peak during the same four months makes us suspect that the two are related," lead researcher Dr. Paul Winchester, of the Indiana University School of Medicine in Indianapolis, noted in a written statement.

Birth defects, such as cleft lip, spina bifida and Down syndrome, affect about 3 percent of U.S. newborns. Certain risk factors, including older age, smoking or drinking in mothers, have been established, but researchers are still trying to piece together the other environmental factors that might be at work.

If further studies confirm the current findings, Winchester noted, then there will be yet another modifiable risk factor for birth anomalies.

"What we are most excited about," he said, "is that if our suspicions are right and pesticides are contributing to birth defect risk, we can reverse or modify the factors that are causing these lifelong and often very serious medical problems."

SOURCE: Acta Pediatrica, April 2009.

Copyright © 2009 Reuters Limited.

NEW YORK (Reuters Health) - Eating broccoli sprouts can help keep stomach cancer-causing bacteria at bay, new research from Japan shows.

"This study supports the emerging evidence that broccoli sprouts may be able to prevent cancer in humans, not just in lab animals," Dr. Jed Fahey of Johns Hopkins School of Medicine in Baltimore, who was not involved in the research, said in a press release from the American Association for Cancer Research (AACR). AACR publishes Cancer Prevention Research, the journal where the current findings appear.

Broccoli and broccoli sprouts contain glucoraphanin, a substance the body metabolizes into the powerful anti-inflammatory and antioxidant sulforaphane, Dr. Akinori Yanaka of Tokyo University of Science and his colleagues note in their report.

There is evidence from lab, animal and human studies that sulforaphane can kill Helicobacter pylori, a bacterium "strongly associated" with stomach cancer, they add.

Yanaka and colleagues examined the effects of broccoli sprouts in mice infected with H. pylori and fed a high-salt diet, which can promote stomach cancer.

Rodents fed the sprouts showed less inflammation in their stomach tissue, and less H. pylori in their stomachs, the researchers found. But mice genetically engineered to lack a gene important in producing anti-inflammatory and antioxidant proteins didn't show these effects.

The researchers had 48 people infected with H. pylori eat 70 grams a day of broccoli sprouts or alfalfa sprouts, which don't contain sulforaphane, for eight weeks. In the men and women eating broccoli sprouts, markers of gastric inflammation were significantly reduced. Markers indicating the amount of H. pylori in gastric tissue also fell, but neither changed in the people eating alfalfa sprouts.

Once the study participants stopped eating the sprouts, their markers of inflammation and H. pylori levels returned to pre-study levels.

The findings suggest, Yanaka and colleagues say, that sulforaphane may fight stomach cancer both by reducing inflammation and by fighting H. pylori infection.

They conclude: "The findings in this study strongly suggest that sulforaphane has promise both as an antibacterial agent directed against H. pylori and as a dietary preventive agent against the development of human gastric cancer."

SOURCE: Cancer Prevention Research, April 2009.

Copyright © 2009 Reuters Limited.

NEW YORK (Reuters Health) - People who are obese may have an increased risk of developing the neurological disorder restless legs syndrome (RLS), researchers reported Monday.

In a study of more than 88,000 U.S. adults, researchers at Harvard Medical School found that obese men and women were 42 percent more likely to have RLS than normal-weight study participants.

Abdominal obesity, in particular, was linked to RLS risk. Study participants with the largest waistlines had a 60 percent greater risk than those with the trimmest midsections, according to findings published in the journal Neurology.

RLS causes unpleasant sensations in the legs when a person is at rest, triggering an uncontrollable urge to move the legs to get relief. The cause is unknown, but researchers suspect that an imbalance in the movement-regulating brain chemical dopamine plays a role. Drugs that increase dopamine activity are sometimes used to treat RLS.

Past research has shown that obese adults tend to have lower dopamine activity in the brain than their thinner counterparts, but the relationship between obesity and RLS has been unclear.

"Our study suggests that obesity could be a risk factor for RLS," lead researcher Dr. Xiang Gao told Reuters Health. However, the findings do not prove that obesity leads to RLS, and further studies that follow people over time are needed to confirm obesity as a risk factor, Gao added.

In theory, dopamine could help explain the connection between obesity and RLS. But Gao said there are likely to be multiple mechanisms through which excess weight contributes to the neurological disorder.

One possibility, he noted, is the higher risk of heart disease among overweight adults. Studies have found links between cardiovascular disease and RLS, and it's thought that dysfunction in the blood vessels may play a role in RLS.

SOURCE: Neurology, April 7, 2009.

Copyright © 2009 Reuters Limited.

LONDON (Reuters) - Up to 70 percent of melanoma skin cancers may be triggered by a gene mutation that causes cells to become cancerous after excessive exposure to the sun, researchers said on Monday.

The discovery could lead to better treatments for the most deadly form of skin cancer after scientists at Britain's Institute of Cancer Research established the BRAF gene mutation is often the first event in the cascade of genetic changes leading to melanoma.

Scientists already knew the BRAF gene was frequently damaged in patients with melanoma, but it was unclear if this was a cause or effect of the cancer.

The British institute published its findings in the journal Cancer Cell.

"Our study shows that the genetic damage of BRAF is the first step in skin cancer development," said lead author Richard Marais. "Understanding this process will help us develop more effective treatments for the disease."

The hope is that knowing the genetics behind skin cancer will lead to the development of targeted drugs that can fix the faulty genetic machinery.

While melanoma accounts for only a small percentage of skin cancers, it is responsible for most skin cancer deaths. The disease is characterised by the uncontrolled proliferation of pigment-producing skin cells called melanocytes.

Over-exposure to sunlight is to blame for at least two-thirds of cases as DNA in sunburnt skin cells become damaged, leading to the genetic mutations.

Copyright © 2009 Reuters Limited.