Archives for: March 2004
AUTHORS: Max H. Pittler MD , Katja Schmidt MSc
ABSTRACT: The aim of this meta-analysis was to assess the evidence from rigorous clinical trials of the use of hawthorn extract to treat patients with chronic heart failure.
COMMENTARY: Experts on and manufacturers of commercial preparations containing hawthorn extract were asked to contribute published and unpublished studies. There were no restrictions about the language of publication.
Two reviewers independently performed the screening of studies, selection, validation, data extraction, and the assessment of methodological quality. To be included, studies were required to state that they were randomized, double-blind, and placebo controlled, and used hawthorn extract monopreparations.
Thirteen trials met all inclusion criteria. In most of the studies, hawthorn was used as an adjunct to conventional treatment. Eight trials including 632 patients with chronic heart failure (New York Heart Association classes I to III) provided data that were suitable for meta-analysis. For the physiologic outcome of maximal workload, treatment with hawthorn extract was more beneficial than placebo (weighted mean difference, 7 Watt; 95% confidence interval [CI]: 3 to 11 Watt; P < 0.01; N = 310 patients).
The pressure–heart rate product also showed a beneficial decrease (weighted mean difference, −20; 95% CI: −32 to −8; N = 264 patients) with hawthorn treatment. Symptoms such as dyspnea and fatigue improved significantly with hawthorn treatment as compared with placebo. Reported adverse events were infrequent, mild, and transient; they included nausea, dizziness, and cardiac and gastrointestinal complaints.
These results suggest that there is a significant benefit from hawthorn extract as an adjunctive treatment for chronic heart failure.
STUDY: Major study may explain puzzling hike in cancer cases.
JOURNAL: The Lancet Medical Journal
AUTHORS: Eugina Calle
ABSTRACT: The number of children women have and the length of time they breast-feed them are the most important factors influencing their chance of developing breast cancer — even more important than genetic factors, major new research shows.
COMMENTARY: The landmark study, published this week in The Lancet medical journal, found that if women in the industrialized world breast-fed each of their children six months longer, they could reduce their chance of breast cancer by 5 percent, even if they have a strong family history of the disease.
Experts said the findings help explain the discrepancy between low rates of breast cancer in developing countries and the rising number of cases in wealthier nations.
In the developed world there have been enormous changes over the last 100 years in childbearing patterns and this illustrates that those changes can explain a great deal of the increase in breast cancer rates.
The study involved 200 researchers across the globe examining more than 47 studies that investigated a total of 150,000 women worldwide. The analysis of the pooled information was conducted by epidemiologists at Oxford University in England.
The idea that childbearing is linked to breast cancer dates to 1743, when an Italian researcher called the disease an occupational hazard of nuns, attributing their relatively high rate of breast cancer to their childlessness.
Breast cancer rates really started to climb at the end of the 19th century, and by the 1950s, it was well established that the number of children a woman had was a major factor in breast cancer.
In 1970, a study found that the age at which a woman had her first child was key, but that neither the number of children she had nor her breast-feeding habits mattered.
Since that time, almost every study on breast cancer has confirmed that finding on age at first birth, but there’s been a lot of confusion about whether the number of children and breast-feeding had an effect on breast cancer. Confusion has remained, particularly about the role of breast-feeding, because individual studies have been too small to provide answers, she said.
The Oxford group started by looking at 20,000 women who had only one child and who had never breast-fed, and compared them with women who did not breast-feed but continued to have children.
The risks go down the more children you have. Even if they’d never breast-fed, the risk of breast cancer went down by 7 percent for every additional child.
The researchers also found that, regardless of the number of children, the risk of breast cancer dropped by 4.3 percent for every year the women breast-fed.
It was shown that prolonging breast-feeding and having more children pushes down breast cancer rates.
The magnitude of protection was the same in all women, regardless of other characteristics, such as ethnic origin, drinking habits and age at menopause.
In the developed world, women have on average two or three children and breast-feed each for about two or three months. 50 percent of mothers in the United States, about 25 percent in Europe and about 10 percent in Scandinavia choose not to breast-feed.
A century ago — before oral contraception, infant formula, improved infant survival and career opportunities for women — Western women used to have six or seven children and breast-feed each for about two years — a pattern still dominant in many parts of the developing world.
Today, women in the industrialized world have a 6.3 percent chance of getting breast cancer by age 70, compared with a 2.7 percent chance for their counterparts in poor countries.
Part of the reason is that women in poor countries have children earlier, at about 18 or 19, compared with 23 or 24 in the developed world. But that couldn’t explain all the difference in the breast cancer rates.
People have been struggling to fill that gap. Things like diet, alcohol ... all these things have come up in an attempt to explain the difference. It appears that it’s prolonging breast-feeding and having lots of children that really pushes breast cancer rates down.
There are obviously other determinants, but they are much smaller. Those two factors account for much of the difference in breast cancer rates between developed and developing countries.
The researchers calculated that if western reproductive and breast-feeding habits mimicked those in poor countries, a woman’s breast cancer risk by the age of 70 would fall from 6.3 per 100 women to about 2.7.
The researchers also calculated what would happen to breast cancer risk if women still had only two or three children but breast-fed each for six months longer than the norm of two or three months. That would translate to a maximum breast-feeding time of nine months per baby. They found that the chances of breast cancer would decrease from 6.3 percent to 6 percent, a 5 percent drop.
The National Childbirth Trust, which promotes breast-feeding, said the research clearly shows the benefits for mothers as well as children.
“We hope that this important finding — that the longer women breast-feed, the more they are protected from breast cancer — will encourage more women to consider breast-feeding their baby,” said Belinda Phipps, the chief executive of the trust.
The scientists are not sure how childbirth and breast-feeding reduce breast cancer risk but they believe the findings could pave the way for better prevention and treatment methods.
STUDY: Choosing low-calorie foods--can help people who just can't seem to resist the temptation to eat
JOURNAL: American Journal of Clinical Nutrition 2002;75:476-483
AUTHORS: Dr. Susan B. Roberts
ABSTRACT: A person's degree of inhibition when it comes to chowing down on snacks and goodies is tied to his or her likelihood of being overweight, according to researchers at Tufts University in Boston, Massachusetts.
COMMENTARY: The good news is that using some restraint--for example by choosing low-calorie foods--can help people who just can't seem to resist the temptation to eat.
The reasons why some people are able to stay trim while others gain weight remain unclear, Roberts and her colleagues note in the current issue of the American Journal of Clinical Nutrition.
To investigate the role of eating behavior in weight gain, the researchers evaluated three eating behaviors--restraint, disinhibition and hunger--as well as the weight and height of 638 healthy, non-smoking women aged 55 to 65.
Restraint is the ability to consciously restrict food intake in order to maintain weight or lose pounds. Disinhibition is the inclination to overeat when tempting food is available, or to overeat in the presence of factors that can loosen inhibitions, such as emotional distress, regardless of whether or not a person is hungry. Hunger is a person's sensitivity to feelings indicating a need for food.
The researchers found that the higher a person's degree of disinhibition, the higher their weight.
The main finding of the study is that disinhibited eating is very strongly associated with obesity.
Being disinhibited also predicts adult weight gain--30 pounds more over 25 years up to age about 60 years.
However, being a restrained eater also helps offset the effect of disinhibition. Restrained eaters are those who count calories (and) tend to shop for low-fat foods. So these behaviors seem to help some, but not as much as not overindulging when you don't need to.
Roberts recommends that people who are concerned about their weight fight the urge to gobble up all the food that is offered to them. Instead, Roberts tells people to think about whether or not they are hungry and not to assume that if they overeat at one meal, they will eat less later.
If you really want (the food) but you are not hungry, take a really small piece...(and) don't finish large portions just because they are there. Save them for another day.
STUDY: Something to think about
JOURNAL: Rheumatology international.; 2003 Jul 16;() p0
AUTHORS: Endresen G
ABSTRACT: Chronic fatigue syndrome (CFS) and fibromyalgia syndrome (FMS) are characterised
by a lack of consistent laboratory and clinical abnormalities.
Although they are distinguishable as separate syndromes based on established criteria, a great number of patients are diagnosed with both. In studies using polymerase chain reaction methods, mycoplasma blood infection has been detected in about 50% of patients with CFS and/or FMS, including patients with Gulf War illnesses and symptoms that overlap with one or both syndromes.
COMMENTARY: Such infection is detected in only about 10% of healthy individuals, significantly less than in patients.
Most patients with CFS/FMS who have mycoplasma infection appear to recover and reach their pre-illness state after long-term antibiotic therapy with doxycycline, and the infection can not be detected after recovery.
By means of causation and therapy, mycoplasma blood infection may permit a further subclassification of CFS and FMS. It is not clear whether mycoplasmas are associated with CFS/FMS as causal agents, cofactors, or opportunistic infections in patients with immune disturbances.
Whether mycoplasma infection can be detected in about 50% of all patient populations with CFS and/or FMS is yet to be determined.
STUDY: Heart Rate and Immunity
JOURNAL: Brain, Behavior, and Immunity 2002;16:411-420
AUTHORS: Dr. Noha H. Farag
ABSTRACT: The temporary rise in blood pressure that accompanies a stressful situation can be caused by an increase in heart rate and a stiffening of blood vessels. Now, researchers report that people who are more likely to experience a rapid heart rate may also be more prone to problems with immunity.
COMMENTARY: The findings may help to explain why chronic stress can lower immunity and make some people more prone to inflammatory diseases such as atherosclerosis.
The researchers took blood samples and monitored the heart rates of 49 healthy adults who were asked to give a speech in response to two stressful scenarios. First, study volunteers talked their way out of shoplifting accusations and then confronted a car dealer for failing to honor a warranty. The volunteers were categorized as "cardiac" or "vascular" reactors. For cardiac reactors, the main stress response was an increase in the heart rate, while vascular reactors showed increased blood vessel stiffness.
The cardiac reactors showed changes in immune system activity not seen among those in the other group. Specifically, there was an increase in the numbers of certain immune cells suggesting that cardiac reactors have a greater immunological response to stress.
These cells, known as lymphocytes, are involved in the "fight or flight" response in which certain hormone levels rise to prepare the body to confront a physical or emotional challenge.
Cardiac and vascular reactors can be differentiated on the basis of immunological changes.
Interestingly, it is only cardiac responders that show a significant redistribution of lymphocytes in response to stress.
STUDY: Surgery to remove a child's tonsils or adenoids may be unjustified
JOURNAL: Pediatrics 2002;110:7-15
AUTHORS: Dr. Jack L. Paradise
ABSTRACT: Surgery to remove a child's tonsils or adenoids may be unjustified if the child's recurrent throat infections are less than severe, new study findings suggest.
COMMENTARY: Children who haven't had a lot of trouble with their tonsils should not have surgery. It's not free of risk and it's a relatively major operation.
Paradise and his colleagues studied 328 children aged 3 to 15 who suffered repeated throat infections to determine whether or not tonsillectomy was always warranted. Because most tonsil removal operations also involve the removal of the child's adenoids, they examined whether this additional operation provided greater benefit.
The children were divided into two groups, which consisted of 151 children who had recurrent ear infections and obstructed nasal passages, indicating a need to have their adenoids removed, and 177 children without such symptoms.
Overall, the children who underwent surgery had lower rates of later throat infections than did children in a comparison group who did not have surgery, the investigators report in the July issue of Pediatrics. However, their overall rates of moderate or severe infections were relatively low, the researchers note.
For example, in any given year of follow-up, 70% to 84% of children in the two study groups did not experience any throat infections. And over the 3 years of follow-up only about 11% of the throat infections were moderate or severe.
Furthermore, adenoid removal surgery was of no additional benefit, the authors point out.
"Like any other operation in medicine (adenoid removal surgery) is useful for selected patients but shouldn't be done for children who don't need it," Paradise said.
Roughly 8% of the 203 children who had their tonsils or their tonsils and adenoids surgically removed experienced hemorrhage, red rashes or some other type of complication either during or after surgery, the report indicates.
In light of the findings, Paradise advises parents not to rush to have their child's tonsils removed. "Make sure the children are really having a lot of difficulty because most children tend to outgrow their symptoms," he said.
Here at the clinic we treat many children with great success.
STUDY: Women who consume cranberry juice (Vaccinium macrocarpon) on a daily basis may help prevent the urinary tract infections (UTIs)
JOURNAL: Journal of the American Medical Association (2002;287:3082–3)
ABSTRACT: Women who consume cranberry juice (Vaccinium macrocarpon) on a daily basis may help prevent the urinary tract infections (UTIs), according to a new study in the Journal of the American Medical Association.
COMMENTARY: Urinary tract infections are bacterial infections of the bladder that affect women more often than men and can lead to infection in the kidneys if untreated. Antibiotics are recommended by most doctors to treat UTIs, but the incidence of antibiotic resistance has increased dramatically over the last couple of decades.
New strategies are now needed to help in the prevention and treatment of a condition that leads to over 11 million physician visits each year in the United States.
Researchers collected urine specimens from 39 women between 18 and 39 years old with confirmed bladder infections with E. coli (the most common cause of UTIs), before and after they had consumed 240 ml (approximately 8 ounces) of cranberry juice. Most of the women had bladder infections that were resistant to antibiotics.
A series of test tube studies was then performed to determine whether cranberry juice could prevent the E. coli obtained from the women's urine from sticking to bladder cells.
Urine specimens collected from 80% of the women after cranberry juice consumption prevented E. coli from adhering to bladder cells, whereas none of the urine specimens collected prior to drinking cranberry juice blocked this process.
These findings suggest that cranberry juice protects the bladder against E. coli infection, even against strains of E. coli that are resistant to antibiotics. However, it is unknown whether cranberry juice would have the same effect against other types of bacteria that cause urinary tract infections.
Another herbal treatment that may be helpful for UTIs is uva ursi (Arctostaphylos uva-ursi). Studies show that uva ursi is an effective treatment for bladder infections, even if the infection is caused by bacteria other than E. coli. The product used in these studies was a standardized extract containing 400 to 800 mg of arbutin per day.
Other herbs that have historically been used by herbalists and may be helpful include goldenseal (Hydrastis canadensis), goldenrod (Solidago sp.), juniper (Juniperus communis) and buchu (Agathosma betulina), but scientific studies have not yet been done to determine whether they are effective.
For more specific information on herbal treatments and amounts to take, consult a practitioner of herbal medicine.
It is important to note that most herbal remedies for bladder infections should not be used continuously for more than two weeks. On the other hand, cranberry juice has been safely used for prolonged periods of time.
These herbs are also not appropriate to use for kidney infections. If you develop fever, chills, nausea, vomiting, or severe back pain, consult a physician immediately.
STUDY: New Avoid: Negative Feelings
JOURNAL: The Proceedings of the National Academy of Sciences
ABSTRACT: Most people accept the idea that stress and depression chip away at the body's natural ability to fight off disease. But many medical scientists have remained skeptical that the mind can exert such a direct influence over the immune system.
COMMENTARY: In recent years, however, evidence has accumulated that psychology can indeed affect biology. Studies have found, for example, that people who suffer from depression are at higher risk for heart disease and other illnesses.
Other research has shown that wounds take longer to heal in women who care for patients with Alzheimer's disease than in other women who are not similarly stressed. And people under stress have been found to be more susceptible to colds and flu, and to have more severe symptoms after they fall ill.
Researchers at the University of Wisconsin are reporting today that the activation of brain regions associated with negative emotions appears to weaken people's immune response to a flu vaccine.
During a task that required experiencing negative emotions, greater electrical activity in the brain's right prefrontal cortex predicted a weaker immune response six months later, as measured by the subjects' level of antibodies to the flu shot, the researchers found.
Greater activation in the left prefrontal cortex was associated with a stronger immune response.
The right prefrontal cortex are active during emotional responses involving anger, fear and sadness.
The left prefrontal cortex appears to be more active in association with positive emotions, like feeling enthusiastic and upbeat, according to the research.