Archives by Author: Laura Blue
How Safe is Gastric-Bypass Surgery?
It's one of the most famous procedures in surgery—and one of the most radical and effective medical treatments for obesity. But how safe is bariatric surgery, also known as gastric-bypass surgery or (more crudely) stomach-stampling?
A study of 86,520 bariatric-surgery procedures conducted in 17 states between 2002 and 2004 has uncovered a big difference in the health outcomes from bariatric surgery. The survey—by the for-profit hospital-ranking service HealthGrades—found that patients at hospitals with the highest success rates were 66% less likely to suffer a major surgery complication than patients at hospitals with the lowest success rates.
Complications from bariatric surgery, which helps patients lose weight by constricting the stomach to limit food intake, include bleeding and respiratory and cardiac problems. The hospitals with the fewest complications, it seems, are the also ones that performed the procedure most often. Those hosptials whose quality results merited a five-star score from HealthGrades conducted roughly twice as many bariatric surgeries as those receiving a one-star score.
What it means: No surgery is without risk, and bariatric surgery is a serious procedure: the U.S. Department of Health and Human Services' Agency for Healthcare Research and Quality announced in July that 4 in 10 patients suffer complications within six months. (Only 2 in 1,000 of the HealthGrade study had complications while still in hospital.)
Still, this is not the first study to suggest that even good doctors can perform poorly if they're carrying out an unfamiliar procedure. If you have a choice about where you undergo surgery, it doesn't hurt to do research which institutions specialize in the procedure you need.
From the Archive:
Nov. 17, 2003: Desperate Measures
Jun. 19, 2006: The Politics of Fat
Who's Having Sex?
Kids aren't
having sex at younger and younger ages. Africans do not typically have
more sexual partners than people in the West, even though HIV/AIDS has
spread rapidly on their continent. Married people have more sex than
the single—and marriage is not always a good defense against STDs.
All of these
are findings of the first comprehensive global study of sexual
behavior, published in <i>The Lancet</i> last week. The
study's authors, led by Kaye Wellings of the London School of
Hygiene and Tropical Medicine, reviewed survey data from 59 countries
that had been collected since 1996 by researchers in medicine, public
health, and social sciences. Wherever possible, Wellings and her team
then compared the recent data to survey results collected over the
previous two decades.
The
conclusions? The study suggests that globally there has been less
change in sexual behavior in recent decades than is often assumed. More
people are having pre-marital sex, the authors say, but much of this is
attributable to the rise in average marriage ages around the world.
Although there are significant regional differences—the median age at
which middle-aged men in Indonesia lost their virginity, for example,
is 24.5 years—almost everywhere men and women lose their virginity
when they are aged 15 – 19.
Researchers
note the surprising lack of clear link between sexual behavior and
sexual health. High rates of sexually transmitted diseases, like AIDS,
are not strongly associated with promiscuous populations. Instead,
factors like education and condom use may keep the relatively
promiscuous Westerners in better health than poorer counterparts.
What it means: This is the
first time anyone has set out to do a large-scale study of sexual
behavior all over the world. As a result, the study has great value not
just in debunking myths about sex, but also in shaping sexual-health
policy. The researchers note, however, that the data vary greatly from
country to country. They caution that it is simply not possible to
develop a sexual-health program that would fit every community. They
stress that policy should focus on what they see as the underlying
determinants of sexual health—poverty, mobility, and gender equality—not just individuals' sexual choices.
However, there are
significant problems with the study's data. The study's authors say
there are limited sources available from the Middle East and parts of
Asia. Globally, men reported many more sexual partners than women—which suggests a tendency for women to under-report the number of
people they sleep with or for to men over-report, or both. (Other
explanations for the discrepancy, researchers suggest, is that women
who sleep with many men, like sex-trade workers, are underrepresented
in sexual-behavior surveys.) Still, the global study of sexual health
goes a long way towards busting myths and providing information on
which to base public-health interventions.
From the Archive:
Jun. 21, 2006: The "Promiscuity" Vaccine
Jun. 15, 2006: Where'd You Learn That?
Suggesting that Women are Worse in Math
Even suggesting to women that men may be naturally better at math can cause those women to underperform, according to a new study published last week in Science.
In two separate trials, researchers at the University of British Columbia gave more than 220 women a three-part test to study stereotypes and math performance. The test was divided into two math sections, separated by one of four essays about gender and math performance which the women were told was a reading-comprehension test. Women who received essays reminding them that females tend to score worse on math tests than males had markedly lower scores on the second math section than women who read essays that argued there was no math-related gender difference.
The most remarkable result, however, was that women who received an essay that argued experiences —for example, favoritism toward boys in math class—account for differences between men's and women's math performance scored just as well as women who were told there was no difference in performance between the genders at all. But women who read an essay that argued genetics account for men's better performance scored as poorly as women who were reminded of the stereotype with no explanation of the cause.
What it means: The study did not address whether men and women do in fact have innate differences that affect the way they do math—still a hot-button issue. But it reminds readers that people can be very suggestable, and stereotypes can be self-perpetuating. The researchers note that studies on other groups have shown similar results about stereotype and performance: for example, one study in American Psychology in 1997 found that African Americans performed worse on intelligence tests when their race was highlighted.
Because participants in the current study scored significantly better when nuture, rather than nature, was used to explain the math-and-gender stereotype, it seems people believe they have more control over how society influences their abilities than over how genes influence them. The most significant conclusion, then, may be that scientists should take care when explaining their results linking genes to certain traits—and that teachers and other communicators should be careful about how they explain scientific theories to students and to the public. Even suggesting that a group of people may be naturally bad at something can reinforce stereotypes and lead to underperformance.
From the Archive:
Mar. 7, 2005: The Math Myth
Your Insect Bite Might be Staph
MRSA – a type of staph infection resistant to many common antibiotics – is now the most common cause of skin infections brought to U.S. emergency rooms. That's the finding of UCLA researchers publishing in today's New England Journal of Medicine.
The researchers looked at 422 adults who visited 11 metropolitan emergency rooms with culturable acute skin or soft-tissue infections in August 2004. While the rates of MRSA varied between the cities, located across the U.S., the bacteria were a significant problem in all. In ten of the 11, MRSA was the most common cause of infections presented, and in nine of 11 MRSA accounted for more than half of all infections, says Dr. David Talan, an author on the study and a professor of medicine in the Department of Emergency Medicine and Division of Infectious Diseases at Olive View-UCLA Medical Center. All told, 249 of the 422 patients – 59% – were found to have MRSA.
Doctors worry about methicillin-resistant Staphylococcus aureus, better known as MRSA, because drug-resistance makes the MRSA infections very tough to treat. In the past, MRSA has posed huge challenges in hospitals, where frail patients have difficulty fighting it off. Only more recently has MRSA spread to other communities in the U.S. where people have a lot of contact, for example among members of sports teams or among prison inmates. "Now it's sort of past a tipping point where it's common in the general population," says Talan.
In fact, since the data from this latest report is from 2004, the findings may underrepresent the current scope of the problem. Many reporting mechanisms in the U.S. suggest MRSA is on the rise.
What it Means: Although the study only includes data from metropolitan areas, it is the largest and most geographically diverse study of its kind to date in the U.S., Talan says. And the findings, which showed cases of MRSA in all the cities submitting data, suggest that MRSA is now common all over the country.
Studies are underway to determine which drugs are most effective at combatting MRSA, but early trials have already given researchers strong hints about which treatments work best. Now it's up to doctors to keep track of those developments so patients can get effective treatment. The report's authors also caution that doctors should not assume every skin infection they see is the common staph – so common and so easily treated in the past. That may mean culturing more infections before prescribing antibiotics in the future.
Patients also have a role to play. Basic measures like avoiding others' used bandages and keeping skin clean (especially frequent hand washing) are easy ways to cut the risk of infection. Patients who do develop a warm, red lesion should consider seeing a doctor. MRSA is more likely than other types of staph infection to occur in skin where there's been no cut or wound already, so the infection is sometimes mistaken for an insect or spider bite. But as with many things, the sooner MRSA is detected, the easier it is to treat – and the easier it is to prevent it from spreading.
From the Archive:
Jun. 26, 2006: Surviving the New Killer Bug
Aug. 4, 2006: A Tale of Two Infections
Why the Wealthiest are Healthiest
It's no secret America's rich are healthier than its very poor. But
a new study released in the New England Journal
of Medicine shows that wealthy baby-boomers and seniors also
suffer from fewer disabilities than those Americans who
earn only slightly less.
The new study linking disability and income, led by a professor at
UC Berkeley's School of Public Health, is based on data from 335,000
Americans aged 55 and older that was collected in the Census 2000
American Community Survey. Many previous studies have shown a link
between life expectancy and income, but researchers here looked at the
relationship between earnings and "functional limitations": long-term
conditions that seriously hinder one or more basic activities, like
walking or lifting objects. Among those aged 55 to 74,
researchers found, functional limitation is associated with income,
just as longevity is.
According to the survey, 80,791 of the respondents suffered from a
functional limitation. Perhaps unsurprisingly, there were significant
differences in disability rates among the poorest and the richest. But
even in the higher income brackets, among people earning six or seven
times the poverty cut-off ($8,259 per year for a senior living alone),
disparities were evident. For example, men aged 65 to 74 who earned
600-699% of the poverty cut-off were 44% more likely to suffer a
functional limitation than men of the same age who earned 700% or more.
What It Means: Long-term physical limitations, like life expentancy, are linked to
income. Although most people don't have the option to make themselves
richer, less wealthy individuals who worry about their health can take
comfort: at least some of the affluent's healthy lifestyle traits can
be mimicked with a bit of work. The study's authors suspect that rich people
suffer less partly because wealth makes it easier to follow up on good
intentions. The rich generally live in safer, less polluted
neighborhoods where walking may be easier. Comprehensive health
insurance policies also encourage regular check-ups and early intervention
for conditions requiring treatment. And the rich are less likely to
smoke. With some dedication, a health-conscious middle-class American
might be able to follow similar healthy patterns.
For policy experts, however, the study is a reminder that
socioeconomic status remains a major determinant of health. Public
health programs should account for the fact that whatever the reasons
may be, poorer Americans generally suffer from physical disabilities
more often than the rich.
From the Archive:
Jun. 23, 2006: San Francisco's Universal Health Care
Mar. 27, 2006: The Politics of Fat
Vitamins Don't Always Help in Pregnancy
Antioxidants don't protect against a common condition in pregnant women that can lead to premature birth, low birthweight, and—in severe cases—death of the mother or her baby, a study published in The New England Journal of Medicine has found.
Pre-eclampsia, a disorder characterized by hypertension and protein in the urine, occurs in the second half of some 5% to 10% of pregnancies. Symptoms can include swelling, headaches, and changes in vision. Pre-eclampsia is a major cause of death among pregnant women in developing countries and is the root of 15% of premature births and associated complications in the U.S., the NEJM reports.
Since low levels of antioxidants have been linked to pre-eclampsia, some scientists had suggested that women given extra antioxidants would be better defended against the condition. To test the hypothesis, an Australian team conducted a randomized trial of 1,877 women who were between 14 and 22 weeks into their pregnancy. All were pregnant with their first child—first-time mothers are at greater risk—and were healthy, with normal blood pressure when the trial began. The women were given 1000 mg of Vitamin C and 400 IU of Vitamin E, both of which are antioxidants.
The results showed little impact. The women who took vitamin supplements did not have significantly lower rates of developing pre-eclampsia. Nor were rates of low birthweight, or serious illness or death in the infant meaningfully different.
What It Means: Healthy pregnant women will not decrease their odds of pre-eclampsia by taking antioxidants. In fact, scientists know of little that can be done to prevent pre-eclampsia: calcium and low-dose aspirin have not had meaningful effects on the condition in other studies either.
It's still unclear, however, whether vitamin treatment might be more beneficial to women in the Third World, where diet may include fewer antioxidants. But at least one study in developed nations—published in The Lancet earlier this year—found that women at increased risk of pre-eclampsia who were given antioxidants actually had even higher rates of certain complications, including low birthweight, than those in the placebo group. Given the minimal benefits of antioxidant vitamins and the possible risks, researchers do not recommend regular use of the supplements to prevent pre-eclampsia.
From the Archive:
03/30/2006 Antioxidant Overload and Pregnancy
10/28/2004 Born Too Soon
Health Effects of Mercury Fillings
Mercury by itself is toxic, but using the heavy metal in dental work does not seem to pose a health risk. That's the finding of two separate studies, both published in the April 19 issue of the Journal of the American Medical Association. In them, investigators measured the neurological and kidney function of children who had cavities filled with silver amalgam (which contains mercury) vs. kids with fillings made from mercury-free material.
The new studies are the first randomized trials to look at the health impact of mercury vapor released from fillings. It's long been known that people with long-term exposure to mercury vapors can suffer tremors, memory loss, lack of coordination, and psychiatric ills. But there has been some dispute over whether the small amount of mercury in fillings could cause problems.
Both JAMA studies tracked several hundred children over a few years to find out. (The first followed 534 New England children, aged six to 10, with an average of 15 tooth surfaces restored over five years. The second looked at 507 children, aged eight to 10, in Lisbon, Portugal.) Both found that kids in the amalgam group had higher levels of mercury in their urine, but neither found any negative health affects as a result. Most importantly, there was no statistically significant difference in memory, IQ, attention, or visual motor function between the kids with amalgam fillings and those without.
What It Means: The studies conclude that there's no reason to avoid amalgam fillings. In fact, silver fillings have some advantages over plastic ones. The amalgam typically lasts longer than resin composite materials—and it's usually a lot cheaper too.
From the Archive:
08/19/2002 White Is the New Mercury
12/11/1995 Are Your Teeth Toxic?
Heart Problems in the Tall
Tall people may have plenty of advantages in life. But they are also more likely to suffer atrial fibrillation—an abnormal quivering of the heart's upper chambers or atria—than shorter people, according to a study appearing this month in the Journal of the American College of Cardiology. Unlike ventricular fibrillation, which affects the lower, pumping chambers of the heart, atrial fibrillation is not usually life-threatening, although it can sometimes lead to stroke.
Researchers decided to study the relationship between stature and heart function because of a known link between atrial fibrillation and the size of a person's left atrium. The scientists had hypothesized—correctly, it seems—that bigger people, with bigger left atria, would be at higher risk for atrial fibrillation. (Another tip-off to the scientists: large animals, like horses, frequently suffer from the condition, while smaller animals do not.)
Researchers from Georgia and Kentucky analyzed data from a registry of more than 25,000 people who had another heart problem, left ventricular dysfunction, and noted a clear link: the prevalence of AF was 32% higher among the tallest quartile of patients than it was among the shortest.
<b>What It Means</b>: Since adults can't change their height, there is unfortunately little or nothing that can be done to affect this risk factor.
The study does go a long way to explain, however, why men are more likely than women to experience atrial fibrillation.
And tall patients should be aware, doctors say, that they may need more aggressive treatment or lifestyle changes to mitigate other risk factors for stroke. AF is the most common sustained cardiac arrhythmia, becoming increasingly likely as a patient ages. The American Heart Association estimates AF affects 3% to 5% of people over 65.
From the Archive:
11/27/2000 The State of the Heart
12/20/1999 A Candidate's Racing Heart
Too Much of a Good Thing
JOE BATOR / CORBIS
The Journal: Journal of Advanced Nursing
The Study: More than half of feverish children are medicated incorrectly by their parents.
Australian researchers combed through more than 70 studies published worldwide in the past 20 years to see how parents' medication habits had changed over time and found that, overall, the trend has been towards increased medication. Even though the proportion of parents giving their children correct doses has increased (from about a third in the 1980s to nearly half in the most recent studies), more than half of children are still not treated properly.
Most alarmingly, the investigators found the percentage of parents giving their children overdoses—doses either too high or too frequent—has increased dramatically: 33% of parents now overdose their feverish kids, compared to 12% in 1987.
What It Means: A growing number of parents seem to believe that if a little medicine is good, more must be better. The study's authors suggest a major reason is inaccurate temperature readings or uncertainty about about the child's normal temperature, which leads parents to think the child is sicker than he or she actually is.
The researchers recommend treating children based on overall well-being, rather than just thermometer measurements. The researchers also found some parents were administering different medicines simultaneously, like acetaminophen and ibuprofen, if one didn't seem to be effective immediately.
Perhaps counter-intuitively, younger children and low-weight children are more likely to be under-dosed than others. That might be because parents overcompensate for their children's small size, cutting the recommended dosages by too much.
From the Archive:
01/10/2005 What Risks Lurk in Your Medicine Cabinet?
07/05/2004 Curbing the Drug Marketers
Alcohol's Benefits May Be Overstated
The Journal: Addiction Research and Theory
The Study: Alcohol's potential health benefits may be overstated. Previous studies have shown a link between moderate alcohol consumption and reduced mortality, particularly when it comes to heart disease. A team of scientists from the U.S., Canada, and Australia went through 54 past studies on alcohol use and longevity, however, and found that once data were regrouped to exclude subjects who had stopped drinking because of health concerns, there was no significant relationship between moderate alcohol consumption and life span.
The researchers point to the past practice of counting people who have recently given up alcohol as "abstainers," even though many of those people gave up alcohol because their health was declining, or because they were taking medications that conflicted with alcohol. When moderate drinkers were compared only with long-term abstainers, there was no significant health difference.
What It Means: Moderate drinkers do tend to be in better health; it's just not clear whether drinking is a sign of good health or a cause of it. Despite the large volume of data reviewed, the study's authors say they cannot discount theories that light alcohol use improves health. New studies that account for the possible "abstainer error" are needed before those conclusions can be drawn. The study strongly suggests, however, that the health benefits of alcohol could have been exaggerated in the past.
From the Archive:
08/20/2004 How To Live To Be 100
01/27/2003 Where's the Proof?
