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Events, Immunology, Infectious Disease, Microbiology, Public Health

A look at our disappearing microbes

A look at our disappearing microbes

8146322408_5312e9deb2_zCould obesity, asthma, allergies, diabetes, and certain forms of cancer all share a common epidemiological origin? NYU microbiologist Martin Blaser, MD, thinks so – he calls these “modern plagues” and traces them to a diminished microbial presence in our bodies, caused by the overuse of antibiotics and the increased incidence of caesarian sections.

I attended a recent public lecture sponsored by UC Santa Cruz’s Microbiology and Environmental Toxicology department, during which the charismatic Blaser cited statistics about antibiotic use in childhood. Alarmingly, American children receive on average seventeen courses of antibiotics before they are twenty years old, taking a progressively bigger toll on their internal microbial ecosystems. We also have an unprecedented rate of c-sections – at nearly 33 percent. Babies delivered this way are deprived of contact with their mothers’ vaginal microbes, which in vaginal deliveries initiates the infant’s intestinal, respiratory, and skin flora. Breastfeeding has implications for beneficial bacterial transfer, too.

It’s not news that antibiotics are being overused – Stanford Medicine hosts an Antimicrobial Stewardship Program dedicated to this cause, and the CDC has been hosting a campaign for awareness about appropriate antibiotic use for several years, including their use in farm animals. (Seventy to eighty percent of antibiotic use takes place on farms to promote growth – that is, not for veterinary reasons.)

Overuse leads to antibiotic resistance, a serious problem. Meanwhile, research by Blaser and others – notably Stanford microbiologist David Relman, MD – has shown that abundant bacterial and viral life is essential to healthy bodies, and that imbalances in the microbial ecosystems that inhabit our gut play an important role in the chronic diseases of the modern age. Blaser said he is concerned that we’re going down a path where each generation has fewer and fewer species of microbes; part of his research is to compare human gut biodiversity in different parts of the globe, and people in remote areas of New Guinea have far more variety than those in Western nations.

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In the News, Infectious Disease, Pediatrics, Public Health

Infectious disease expert discusses concerns about undervaccination and California’s measles outbreak

Infectious disease expert discusses concerns about undervaccination and California's measles outbreak

3480352546_ab985b66a6_zStanford’s Yvonne Maldonado, MD, who heads up Lucile Packard Children’s Hospital Stanford infectious disease team, weighed in on California’s measles outbreak last week on KQED’s Forum program.

The state reported 59 confirmed measles cases following an outbreak at Disneyland in December and fueled by high rates of under-vaccination.

“Measles is one of the most infectious viruses in humans that we know of,” Maldonado said. Spread by tiny droplets, measles remains contagious in a room for up to two hours after an infected person has left, she said.

At first, the disease appears like a lot of childhood diseases with three primary symptoms, what doctors call the “3 c’s,” — cough, coryza (runny nose) and conjunctivitis (red, watery eyes). The disease also produces fever, the charactoristic rash and in rare cases, pneumonia or other complications.

“It is not a simple, easy disease to deal with,” Maldonado said.

All children should receive two doses of the vaccine, which is 99 percent effective at preventing the disease, Maldonado said.

Adults who are born after 1957 and do not believe they have had measles, or a vaccine, should also be checked. Although measles has been basically eliminated in the U.S., it is prevalent in other countries and under-vaccination  can lead to outbreaks, the researchers said.

Previously: Measles is disappearing from the Western hemisphere, Measles are on the rise; now’s the time to vaccinate, says infectious-disease expert and A look at the causes and potential cost of the U.S. measles outbreaks 
Photo by Dave Haygarth

Infectious Disease, Parenting, Pediatrics, Pregnancy, Public Health

Cocooning newborns against pertussis

Cocooning newborns against pertussis

Grandparent hand with babyAt my last prenatal visit, I got a booster shot for whooping cough (sometimes called pertussis). The Centers for Disease Control and Prevention recommends women get a booster in the third trimester of every pregnancy. Whooping cough has been on the rise for years, and there’s an outbreak happening in California, where we live.

Newborns are especially vulnerable to severe complications from the disease, so doctors suggest that anyone who’s going to be in close contact with newborns and isn’t up-to-date also get a booster: fathers, siblings and even visiting grandparents. The strategy is called “cocooning.”

But what do you do when a grandparent doesn’t want to get a shot? A lot of people don’t like getting vaccinations, either because they want to avoid the discomfort of a shot in the arm or they don’t believe vaccines are effective. (They are.) It’s a question that comes up more often than I expected in online communities. Many pregnant women insist that grandparents who won’t get pertussis shots won’t be allowed to see the new grandchild. Others argue that you can’t force a medical decision like that on someone else. Throw in the added complication that if you’re a first-time parent, it might be the first time you’ve had to confront your parents about how you plan to raise your child. What a mess.

I’m lucky that most of my daughters’ grandparents are already vaccinated for pertussis: My parents and my mother-in-law came to stay and help us with the baby a few years ago and all got vaccinated at the time. But with all the things occupying us as new parents, we didn’t even think to ask my father-in-law, who lives nearby but didn’t have any extended stays in our home. As it turns out, he’s not a fan of vaccinations, and he insists that he got the flu from his last flu shot. (He didn’t.) Obviously, he hadn’t gotten the pertussis booster.

For this baby, we’re planning on bringing up the shot with him, but we’re not expecting him to actually get one. So what will we do? I surprised myself by deciding that I won’t insist he get one in order to see the baby, as long as he doesn’t have any cold symptoms when he visits. (Pertussis usually starts as a mild cold that gets progressively worse; by the time most people are diagnosed, they’ve been sniffling and shedding pertussis bacteria for weeks since they first showed symptoms.) But, who knows? Maybe Grandpa Lesko will surprise us and get the shot for the baby’s sake – or just to avoid the sniffle quarantine policy.

We’ll see.

Previously: Failure to vaccinate linked to pertussis deathsCDC: More U.S. adults need to get recommended vaccinations, and Whooping cough vaccine’s power fades faster than expected
Photo by Ashley Grant

Patient Care, Pediatrics, Public Health, Research, Stanford News

Study finds gaps in referring California’s tiniest babies to follow-up care

Study finds gaps in referring California's tiniest babies to follow-up care

preemie feet2When very fragile babies go home from the hospital after birth, they often require special follow-up care. But a new Stanford study has found that some high-risk infants aren’t receiving referrals to the follow-up care they need.

The study, which appears in the February issue of The Journal of Pediatrics, analyzed statewide data on more than 10,000 California babies born in 2010 and 2011 who were considered high risk because they had very low birth weights. Of those who survived to hospital discharge, 20 percent did not receive referrals to the state’s high-risk follow-up program.

From our press release on the research:

Babies who weigh less than 3.3 pounds at birth, nearly all of whom are born prematurely, are at risk for a variety of neurologic and developmental problems in childhood. In California, all babies with a very low birth weight who received care in a California Children’s Services-approved neonatal intensive care unit qualify for a state-supported, follow-up program that provides diagnostic assessments and services until they turn 3.

“If we cannot succeed in that first step of getting these babies referred to follow-up, we’re at a critical disconnect for what we can offer them as they grow and develop,” said Susan Hintz, MD, professor of neonatal and developmental medicine and lead author of the study.

The study analyzed which very-low-birth-weight babies were receiving referrals. Neonatal intensive care units that treated more of these babies referred a higher proportion of such patients to follow-up care, and babies with several types of medical problems were more likely than others to receive referrals. Babies whose birth weights were on the higher end of the low-weight category were less likely to get referrals, as were those of African-American and Hispanic descent.

The good news, however, is that the data was collected just after California revamped its high-risk follow-up program. Hospitals with low referral rates are already receiving feedback to help them improve, and those with high referral rates are being studied to see how their successes can be transferred to other settings. More from our release:

“We’ve already made substantial improvements in site-specific online tools and resources available to hospitals for nearly real-time feedback, and referral rates now appear to be higher than they were during 2010 and 2011,” Hintz said.

California is ahead of other states in having a comprehensive, statewide program to help high-risk infants, [she] added. “The expectation that all our high-risk infants will be referred is enormously innovative in this country,” she said.

Previously: Preemies face increased risk of death in early adulthood, Stanford study finds, NICU trauma intervention shown to benefit mothers of preemies and How Stanford researchers are working to understand the complexities of preterm birth
Photo by Jenny

Behavioral Science, Health and Fitness, Medical Apps, Public Health, Technology

What needs to happen for wearable devices to improve people’s health?

What needs to happen for wearable devices to improve people's health?

15353072639_f3a79557df_z“Wearable devices” are pieces of technology that are worn in clothes or accessories, and they often have biometric functionality – they can measure and record heart rates, steps taken, temperature, or sleep habits. Numerous tech companies have begun manufacturing and marketing such devices, which are part of a larger movement often referred to as the “quantified self” – where data about one’s life is meticulously gathered and recorded. Only 1% to 2% of Americans have used a wearable device, but annual sales are projected to increase to more than $50 billion by 2018.

Health and fitness apps are also proliferating, from software that maps where you run or provides a digital workout community, to programs that count calories or suggest how to improve your sleep. But what’s the real impact for people’s health?

Earlier this month, a report from the Journal of the American Medical Association called into question the idea that wearable devices will effect population-scale changes in health. There is a big gap, the authors claim, between recording health information and changing health behavior, and little evidence suggests that this gap is being bridged. Wearable devices might be seen as facilitating change, but not driving it. Mitesh Patel, MD, MBA, from University of Pennsylvania, and colleagues wrote:

Ultimately, it is the engagement strategies—the combinations of individual encouragement, social competition and collaboration, and effective feedback loops—that connect with human behavior.

The difficulty of population health is that changes have to be sustained to have meaningful effects, and that is quite difficult. The authors identify four steps that must be taken to bridge this gap towards sustained change.

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Nutrition, Public Health

Eating for good blood: Tips for boosting iron levels and hemoglobin

Eating for good blood: Tips for boosting iron levels and hemoglobin

eggs and chard

Have you ever gone to donate blood only to be deferred for low iron count? Also referred to as low blood count, low iron, or low hemoglobin, approximately 10 percent of donors are deferred for this reason. When a donor is deferred, that means they’re unable to donate blood that day. You’ve probably wondered why this happens and if there’s anything you can do about it. Hopefully, the following information will shed some light on the subject.

What is iron and what does it have to do with blood donation?

Iron is a nutrient that is found in the foods we eat, which then combines with certain proteins to become hemoglobin in your red blood cells. The red blood cells are important because they carry oxygen from the lungs to other parts of the body. When the body experiences low iron and hemoglobin, this essentially means you do not have enough red blood cells in your body to donate blood. Low iron levels may cause you to feel tired, and extremely low iron levels may cause damage to organs. There are several reasons one may have a low blood count – including not eating enough iron-rich foods, donating blood too frequently, chronic illness, or other invisible causes.

Testing your blood

In order to keep our donors safe and healthy, our collections staff must ensure that each donor we see has sufficient levels of iron and hemoglobin before they donate. Therefore, when you visit a center to donate, the collections staff will do a finger prick to test a small amount of blood to assess hemoglobin levels. If your levels are low, we will not be able to collect your blood that day but do encourage you to try some simple measures to raise your levels in order that you can come back to donate again in the future.

What can I do to improve my hemoglobin levels prior to donation?

One way to try to boost your iron levels is through your diet. By eating iron-rich foods, you can promote blood regeneration and increase the amount of iron in your body. Typically, iron-rich foods are colorful and deeply pigmented. Some examples of good sources of iron include:

  • Chard
  • Dates
  • Eggs
  • Lean beef and pork
  • Raisins
  • Shrimp
  • Spinach
  • Whole grain breads

For a more detailed list of foods and their iron content, the USDA provides a nutrient database for reference.

Kristin Stankus is the digital community & social media specialist at Stanford Blood Center. This blog entry originally appeared on the blood center’s blog.

Photo by Patent and the Pantry

Clinical Trials, Patient Care, Public Health, Research, Stanford News

Screening for diseases doesn’t necessarily save lives, study shows

Screening for diseases doesn't necessarily save lives, study shows

6143531948_a9bdfe6fb5_zIt seems like it should work: If everyone was tested for every disease, lives would be saved, right? These conditions would be spotted quickly, treated and voilà – the deadly disorder would go away.

Not necessarily, according to a new study from a team led by Stanford epidemiologist John Ioannidis, MD, DSc, published this week in the International Journal of  Epidemiology. Here’s Ioannidis:

Screening for diseases that can lead to death typically does not prolong life substantially; a few screening tests may avert some deaths caused by the disease being screened, but even then it is difficult to document an improvement in overall survival.

Ioannidis and his team examined whether screening prevents death in 19 diseases with 39 screening tests, looking at evidence from randomized controlled trials and from meta-analyses combining the results of the trials. Patients were asymptomatic when tested.

In their meta-analysis, the researchers found that mortality from the disease dropped in these cases: ultrasound for abdominal aortic aneurysm in men, mammographyfor breast cancer, and fecal occult blood test and flexible sigmoidoscopy for colorectal cancer. But no other tests reduced the number of deaths caused by the disease in meta-analyses.

What gives?

The test might not be able to detect accurately enough early stages of the disease, or there might not be life-saving treatments available, Ioannidis and colleagues write.

Ioannidis acknowledges that screening might ward off other ill-effects of disease aside from death. But in general, few screening tests among the many new ones being proposed are subjected to a randomized controlled trial before they are introduced, Ioannidis said.

“This is unfortunate. All screening tests should be evaluated with rigorous randomized controlled trials. I see no alternative to prove that they are worth being adopted in large populations,” he told me.

This work follows another recently published paper, in which Ioannidis and colleagues argue that screening all baby boomers for hepatitis C isn’t necessarily beneficial.

Previously: To screen or not to screen for hepatitis C, Bad news for pill poppers? Little clear evidence for Vitamin D efficiency, says Stanford’s John Ioannidis, John Ioannidis, MD: Research’s researcher and Screening could slash number of breast cancer cases
Photo by david_jones

CDC, Chronic Disease, Health Policy, In the News, Infectious Disease, Public Health

To screen or not to screen for hepatitis C

Hep CIn the past few years, newer, more effective treatments have been introduced for hepatitis C – a disease that can lead to chronic liver problems and in the worst cases, liver cancer. In 2012, the Centers for Disease Control and Prevention recommended screening for the disease in anyone born between 1945-1965, since about three-quarters of cases occur in this age group, the Baby Boomers. Last year, the World Health Organization also called for more screening for the disease.

But in a recent analysis piece in The BMJ (formerly the British Medical Journal), several scientists, including Stanford epidemiologist John Ioannidis, MD, DSc, lay out the case that universal screening in this age group may not be warranted. A story in the San Francisco Chronicle today quotes Ioannidis:

“The question is whether these aggressive screening policies are justified and whether they would result in more benefit than harm,” said Dr. John Ioannidis...“We know very little about the potential harms of these drugs, especially in the long-term. And we don’t know how they will translate into long-term benefits.”

Ioannidis and his colleagues suggest that instead of rolling out widespread screening programs, researchers, as soon as possible, start a randomized trial to test the usefulness of screening and who may benefit from it.

On top of the medical uncertainties of the new treatments, they’re expensive, costing about $84,000 for the 12-week treatment. But they’ve been shown to cure patients of their hepatitis C infections at the end of that 12 week stint. Not all people who contract the disease will develop chronic infections, but a majority – two-thirds -will. Twenty percent of those cases will go on to develop severe liver disease.

Advocates of universal screening say that the new screening strategy could identify many people who don’t know they’re sick – symptoms from hepatitis C chronic infections can take years to manifest. But Ioannidis and his colleagues note that many people will get unnecessary treatment and that the long-term uncertainties of the treatment should be taken into consideration.

Previously: Despite steep price tag, use of hepatitis C drug among prisoners could save money overallA primer on hepatitis CFor patients with advanced hepatitis C, benefits of new drugs outweigh costsDrugs offer new hope for hepatitis C and Program examines hepatitis C, the “silent epidemic”
Photo of hepatitis C virus by AJ Cann

Addiction, Pain, Public Health, Research

Medical marijuana and the risk of painkiller overdose

Medical marijuana and the risk of painkiller overdose

medical marijuanaAfter a study published this fall showed that that opioid overdoses (e.g., with painkillers such as Oxycontin) occur at lower rates in states with legalized medical marijuana, many people interpreted the results as proof that using medical marijuana lowers an individual’s risk of overdose. For example, some speculated that marijuana allows people in pain to forgo using opioids or at least use them in lower doses. Other suggested that medical marijuana reduces users’ consumption of alcohol and anti-anxiety medications, both of which make opioid use more likely to lead to overdose. Still others hypothesized that medical marijuana improves mental health, reducing the risk of intentional opioid overdose (i.e., suicide attempts),

However, all of this speculation was premature. Many things that are associated when geographic areas are compared are not associated in the lives of the individuals who reside in those areas. For example, geographic areas with higher rates of cigarette smoking and higher radon exposure have lower cancer rates, even though individuals who smoke and/or get exposed to radon have higher rather than lower risk of cancer.

The only way to understand the influence of medical marijuana on individuals’ risk of opioid overdose is to actually research individuals, and that is what an Australian team has done. In a recently published study of more than 1,500 people who were on prescribed opioids for pain, they examined experiences with medical marijuana.

Seeking pain relief from medical marijuana was common in the sample, with 1 in 6 participants doing so and 1 in 4 saying they would do so if they had ready access to it. The results did not support the idea that medical marijuana users are at relatively low risk of opioid overdose. Indeed, on every dimension they appeared to be at higher risk than those individuals who did not use medical marijuana for pain.

Specifically, relative to individuals who only used opioids for pain, the medical marijuana users were on higher doses of opioids, were more likely to take opioids in ways not recommended by their doctor, were over twice as likely to have an alcohol use disorder and four times as likely to have a heroin use disorder. Medical marijuana users were also over 50 percent more likely to be taking anti-anxiety medications (benzodiazepines), which when combined with opioids are particularly likely to cause an overdose.

Neither did the medical marijuana users have better mental health. Almost two-thirds were depressed and about 30 percent had an anxiety disorder.   These rates were half again as high as those for non-medical marijuana users.

Medical marijuana thus appears to be commonly sought for pain relief among people who are taking prescribed opioids for pain. But in this population, it’s a marker for much higher rather than lower risk for opioid overdose.

Addiction expert Keith Humphreys, PhD, is a professor of psychiatry and behavioral sciences at Stanford and a career research scientist at the Palo Alto VA. He has served in the past as a senior advisor in the Office of National Drug Control Policy in Washington, DC. He can be followed on Twitter at @KeithNHumphreys.

Previously: Assessing the opioid overdose epidemicTo reduce use, educate teens on the risks of marijuana and prescription drugs and Study shows prescribing higher doses of pain meds may increase risk of overdose
Photo by David Trawin

Health Costs, Pain, Public Health, Research

Study examines trends in headache management among physicians

Study examines trends in headache management among physicians

4175034274_63cd0d4a7c_zAn estimated 12 percent, or 36 million Americans, suffer from migraines, resulting in an economic loss of $31 billion each year due to lost productivity, medical expenses and absenteeism.

Making lifestyle changes, such as exercising regularly, getting adequate sleep, reducing stress and cutting food triggers from your diet, have been shown (.pdf) to be effective ways to manage headache symptoms. But research recently published in the Journal of General Internal Medicine shows that physicians are increasingly ordering medical tests and providing referrals to specialists instead of offering counseling to patients on how changing their behavior could relieve their pain. Medical News Today reports:

The study, which analyzed an estimated 144 million patient visits, found a persistent overuse of low-value, high-cost services such as advanced imaging, as well as prescriptions of opioids and barbiturates. In contrast, the study found clinician counseling declined from 23.5 percent to 18.5 percent between 1999 and 2010.

The use of acetaminophen and non-steroidal anti-inflammatory drugs like ibuprofen for migraine remained stable at approximately 16 percent of the medications. Meanwhile, the use of anti-migraine medications such as triptans and ergot alkaloids rose from 9.8 percent to 15.4 percent. Encouragingly, guideline-recommended preventive therapies – including anti-convulsants, anti-depressants, beta blockers and calcium channel blockers – rose from 8.5 percent to 15.9 percent.

Unlike with the treatment of back pain, researchers found no increase in the use of opioids or barbiturates, whose usage should be discouraged, although they were used in 18 percent of the cases reviewed.

Researchers also found a significant increase in advanced imaging such as CT scans and MRIs, from 6.7 percent of visits in 1999 to 13.9 percent in 2010. The use of imaging appeared to rise more rapidly among patients with acute symptoms, compared to those with chronic headache.

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