Wednesday, March 21, 2007

Obesity Doubles Odds of Prostate Cancer Mortality

SEATTLE, March 15 -- Obese men diagnosed with prostate cancer in middle age are at a 2.6-fold higher risk of dying from the disease than are patients of normal weight, according to a case-control study.

Surprisingly, the increased prostate-cancer-specific mortality risk was independent of treatment and key prognostic factors at diagnosis, including disease grade and stage, reported Alan R. Kristal, Dr.P.H., of the Fred Hutchinson Cancer Research Center here, and colleagues, in the March 15 issue of Cancer.

Epidemiology data has consistently indicated a modest increase in prostate cancer mortality among men with a body mass index (BMI) of 30 kg/m2 or greater. However, it was unclear whether the effect was due to poor prognostic factors or an effect on progression after treatment.

So, the researchers looked at 752 men ages 40 to 64 with newly diagnosed, histologically confirmed prostate cancer in the Seattle-Puget Sound Surveillance, Epidemiology, and End Results (SEER) cancer registry.

The men reported their pre-diagnosis height and weight in a baseline interview and were followed through the registry for an average of 9.5 years.

The mean BMI was 26.7 kg/m2, and 17.0% of the men were obese. About a quarter had regional- or distant-stage prostate cancer at diagnosis (27%), and 14% had Gleason scores of 7 or higher. Most underwent radical prostatectomy as the primary treatment (63%).

During follow-up, 50 men died of prostate cancer, 64 died of other causes, and 36 developed metastases.

The researchers found that obesity at diagnosis significantly increased risk of prostate-cancer-specific mortality (hazard ratio 2.64, 95% confidence interval 1.18 to 5.92, P=0.03 for trend) after controlling for age, race, smoking status, and clinical prognostic factors at baseline. Mortality from other causes was not linked to BMI (P=0.40).

The prostate-cancer-specific mortality rates were:

  • 6.5 per 1,000 person-years for normal or underweight men (BMI less than 25 kg/m2).
  • 5.4 per 1,000 person-years for overweight men (BMI 25 to 29.9 kg/m2).
  • 13.0 per 1,000 person-years for obese men.

When the researchers stratified mortality by BMI categories, the adjusted findings were:

  • No significant associations between obesity and Gleason score (P=0.72 for interaction), cancer stage (P=0.78 for interaction), or serum prostate specific antigen level at diagnosis (P=0.11).
  • No significant trend for higher mortality with higher BMI whether the primary treatment was radical prostatectomy (P=0.26 for trend) or androgen-deprivation therapy only (P=0.07 for trend).
  • No significant association between mortality and androgen-deprivation therapy use (P=0.32 for interaction) though there was a suggestion that the risk was higher among those that did not receive it (HR 15.92, 95% CI 1.37 to 85.18).

Obesity also significantly increased the risk of metastasis for men diagnosed with local- or regional-stage disease (HR 3.61, 95% CI 1.73 to 7.51, P=0.0006 for trend). This finding did not vary significantly across BMI strata with Gleason score, cancer stage, or primary treatment.

Mechanisms by which obesity could affect cancer outcomes may include altered steroid hormone concentrations, high levels of leptin and other adipokines, and inflammation, Dr. Kristal and colleagues suggested.

They said their findings were unlikely to be biased by the effects of treatment or diagnosis on weight since men reported their pre-diagnosis weight and androgen-deprivation treatment showed no interaction with reported BMI.

However, they noted that such self-reports may have introduced error.

While it is unknown whether weight reduction post-diagnosis could affect prostate cancer outcomes, the researchers said the study suggests that this avenue should be studied.

"Although a randomized clinical trial would be needed to definitively determine whether weight reduction would be an effective adjunct treatment for men diagnosed with prostate cancer," they wrote, "these results provide yet one more important reason for men to adopt healthful patterns of diet and physical activity to achieve and maintain a normal weight."

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Friday, March 16, 2007

Study shows why exercise boosts brainpower

WASHINGTON (Reuters) -- Exercise boosts brainpower by building new brain cells in a brain region linked with memory and memory loss, U.S. researchers reported Monday.

Tests on mice showed they grew new brain cells in a brain region called the dentate gyrus, a part of the hippocampus that is known to be affected in the age-related memory decline that begins around age 30 for most humans.

The researchers used magnetic resonance imaging scans to help document the process in mice -- and then used MRIs to look at the brains of people before and after exercise.

They found the same patterns, which suggests that people also grow new brain cells when they exercise.

"No previous research has systematically examined the different regions of the hippocampus and identified which region is most affected by exercise," Dr. Scott Small, a neurologist at Columbia University Medical Center in New York who led the study, said in a statement.

Writing in the Proceedings of the National Academy of Sciences, the researchers said they first tested mice.

Brain expert Fred Gage, of the Salk Institute in La Jolla, California, had shown that exercise can cause the development of new brain cells in the mouse equivalent of the dentate gyrus.

The teams worked together to find a way to measure this using MRI, by tracking cerebral blood volume.

"Once these findings were established in mice, we were interested in determining how exercise affects the hippocampal cerebral blood volume maps of humans," they wrote.

They of course could not dissect the brains of people to see if new neurons grew, but they could use MRI to have a peek.

They recruited 11 healthy adults and made them undergo a three-month aerobic exercise regimen.

They did MRIs of their brains before and after. They also measured the fitness of each volunteer by measuring oxygen volume before and after the training program.

Exercise generated blood flow to the dentate gyrus of the people, and the more fit a person got, the more blood flow the MRI detected, the researchers found.

"The remarkable similarities between the exercise-induced cerebral blood volume changes in the hippocampal formation of mice and humans suggest that the effect is mediated by similar mechanisms," they wrote.

"Our next step is to identify the exercise regimen that is most beneficial to improve cognition and reduce normal memory loss, so that physicians may be able to prescribe specific types of exercise to improve memory," Small said.


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Friday, March 09, 2007

Health costs will surge without better prevention

The cost of caring for aging Americans will add 25 percent to the nation's
health care bill by 2030 unless people act now to stay healthy, the U.S.
Centers for Disease Control and Prevention said on Thursday.

Currently, 80 percent of Americans 65 or older have at least one chronic
disease that could lead to premature death and disability, CDC researchers

The report, The State of Aging and Health in America 2007, projects that by
2030, 71 million Americans will be over 65, accounting for 20 percent of the
U.S. population, up from 10 to 11 percent now.

With the cost of caring for older Americans at three- to five-times greater
than care for younger adults, CDC researchers believe policymakers and
individuals should take steps to help aging adults forestall chronic

"Given the demographics ... the economic impact on healthcare will be
enormous," said Dr. Richard Murray, a vice president at Merck & Co. Inc.,
whose foundation funded the study.

If people adopt healthier lifestyles, they will not develop the expensive,
chronic diseases that raise health costs sharply, such as diabetes, cancer
and heart disease.

"We are going to see an increase in health care costs, but the goal has to
be to restrain the rate of increase. Prevention is the key to that," said
Bill Benson, a health care benefits and policy analyst who advised the CDC
on the report.

The report noted that three behaviors -- smoking, poor diet and physical
inactivity -- caused almost 35 percent of U.S. deaths in 2000.


Those three behaviors often lead to the development of the nation's leading
chronic diseases: heart disease, cancer, stroke and diabetes, they said.

"Having a chronic disease that's well managed doesn't necessarily put a
person at risk for functional decline, but when someone starts developing
problems, they are much more at risk," said Lynda Anderson, a chronic
disease and aging expert at the CDC.

The report looks at how states are faring in terms of elderly health and
providing preventive care such as immunizations and health screenings and
taking steps to prevent falls, a major risk for the elderly.

"You have some regions that are doing extremely well in a lot of areas and
others that are struggling to get these services to older adults," she said.

Elderly people in Hawaii, for example, are likely to fare better in many key
measures of health. The state ranked best in overall health, mental health,
and disability and had the lowest percent of obese elderly. But Hawaii
ranked last in terms of screening for colorectal cancer.

West Virginia ranked worst in terms of overall health, oral health and
disability, while Kentucky had the highest level of elderly people reporting
mental health problems. Louisiana reported the highest levels of obesity,
with more than 25 percent of the elderly population considered obese.

"There are certainly areas that we need to really pay attention to,"
Anderson said.

She hopes the data will give state policymakers the right tools to start
building prevention programs now, before chronic disease begins.

"We have the opportunity for prevention," Merck's Murray said. "We need to
be serious about it."


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Tuesday, March 06, 2007

Exercise Helps Slow Smokers' Lung Function Decline

Activity levels tied to 21% drop in new cases of chronic obstructive pulmonary disease

THURSDAY, March 1 (HealthDay News) -- Moderate to high levels of regular exercise may help slow lung function decline in smokers and lower their risk of developing chronic obstructive pulmonary disease (COPD), a Spanish study suggests.

Researchers publishing in the March issue of the American Journal of Respiratory and Critical Care Medicine examined the physical activity, smoking history and lung function of nearly 6,800 people over 11 years. None of them had COPD at the start of the trial, but 928 of the participants developed the lung disease during the study.

The researchers found that moderate to high levels of exercise among smokers in the study were associated with a 21 percent decline in potential new cases of COPD. They believe that regular exercise suppresses the production of inflammatory markers in the lungs caused by smoking.

It had been believed that quitting smoking and reducing occupational exposure to smoke were smokers' only options for slowing lung function decline. This study showed that exercise may provide another important option, the study authors said.

"The interaction between physical activity and smoking should be taken into account when projecting the future burden of this respiratory disease," researcher Dr. Judith Garcia-Aymerich, of the Center for Research in Environmental Epidemiology at the Institut Municipal d'Ivestigacio Medica in Barcelona, said in a prepared statement.

COPD, the fourth leading cause of death in the United States, results from chronic bronchitis and emphysema. Smoking is the primary cause of COPD.


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Obesity May Trigger Earlier Puberty for Girls

Breast development at 9 linked to weight gain in younger years, study finds

MONDAY, March 5 (HealthDay News) -- Childhood obesity may lead to earlier onset of puberty for girls, a U.S. study concludes.

The study of 354 girls from 10 different regions in the United States found that increased body fat in girls as young as age 3 and large increases in body fat between the age of 3 and the start of first grade were associated with earlier puberty, defined as the presence of breast development by age 9.

"Our finding that increased body fatness is associated with the earlier onset of puberty provides additional evidence that growing rates of obesity among children in this country may be contributing to the trend of early maturation in girls," study lead author Dr. Joyce Lee, a pediatric endocrinologist at the University of Michigan, said in a prepared statement.

Her team published the findings in the March issue of Pediatrics.

Lee noted that girls in the United States are entering puberty at younger ages than they were 30 years ago. Over that same time, there's been a significant increase in obesity rates among American children.

"Previous studies had found that girls who have earlier puberty tend to have higher body mass index (BMI), but it was unclear whether puberty led to the weight gain or weight gain led to the earlier onset of puberty. Our study offers evidence that it is the latter," said Lee, who is also assistant professor in the department of pediatrics and communicable diseases at the U-M Medical School.

"Beyond identifying how obesity causes early puberty, it's also important to determine whether weight control interventions at an early age have the potential to slow the progression of puberty," she noted.

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Friday, March 02, 2007

BabyCenter, LLC, is the leading online resource for new and expectant parents

SAN FRANCISCO, Feb. 22 /PRNewswire/ -- According to BabyCenter, LLC,
("BabyCenter") the leading online resource for new and expectant parents, a
majority of women increase their focus on health, fitness and nutrition once
they become a mother, than before they planned to conceive and/or had a
child. New research shows approximately 65 percent of women exercise more or
try to exercise more since becoming mothers, and 82 percent reported eating
healthier since becoming a mom.

"We found that becoming a mom is a catalyst for getting healthy. Women begin
making diet and exercise changes during pregnancy and those changes stay
with them long after the baby is born. In our survey, three out of four
women say they change their eating habits during pregnancy and after their
kids are born, and more than half say they exercise more since becoming
moms," said Linda Murray, editor in chief, BabyCenter. "Motherhood is good
for your health."

BabyCenter(R) recently surveyed approximately 600 members looking for
greater insight on the role of health and nutrition in women in the
preconception and pregnancy stages. The research, conducted in partnership
with AVEENO(R) Baby, a Johnson & Johnson Consumer Products Company brand and
leader in ACTIVE NATURALS(R) technology, found of the 40 percent of members
planning to begin or expand their family in 2007, there was an overall
commitment to healthier lifestyles whether trying to conceive, while
pregnant, or while caring for a baby or toddler.

More than 75 percent of the women in the survey reported that being
physically fit is somewhat or very important. Most moms, 57 percent,
exercise on a weekly basis, with the majority walking to stay in shape.
Nearly a quarter of pregnant moms say they plan to take yoga.

"Walking is one of the best exercises for moms-to-be. It's safe throughout
pregnancy and easy to start doing even if you've never exercised before.
Regular strolls are also a great stress reliever," said Murray.

Since becoming pregnant, 14 percent of moms increased their amount of
exercise, while 43 percent exercised less often. At least 55 percent of
pregnant moms exercised on their own while their child was occupied or in
the care of others, while 41 percent exercised with their child in or out of
the home. Only eight percent belonged to parent/child interactive exercise

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