The five most-read stories this week on Scope were:

What other cultures can teach us about managing postpartum sleep deprivation: A recent Huffington Post piece from the Stanford Center for Sleep Sciences and Medicine examined how mothers in other countries cope with postpartum sleep deprivation.

Stanford bioengineer develops a 50-cent paper microscope: Manu Prakash, PhD, assistant professor of bioengineering, has developed an ultra-low-cost paper microscope to aid disease diagnosis in developing regions. The device is further described in a technical paper.

How much caffeine is really in one cup of coffee?: As described in a Scientific American piece, new research shows the caffeine and caffeoylquinic acid content can vary greatly depending on the type and preparation of coffee.

Why sleeping in on the weekends may not be beneficial to your health: This blog entry links to a Wired Science article describing the dangers of oversleeping.

In medicine, showing empathy isn’t enough: In the latest installment of our SMS Unplugged series, medical student Moises Gallegos discusses some of the things he’s learned and observed about health disparities.

And still going strong – the most popular post from the past:

The mystery surrounding lung-transplant survival rates: A 2012 article in the San Francisco Chronicle offered a look at the challenges facing lung transplant patients and explored why a significant number don’t live beyond the five-year mark, despite improvements in survival rates.

This summer high school students from around the Bay Area are interning at labs and departments across Stanford. A recent Stanford Report story highlights the type of projects students are working on and how the internships provide them with valuable work experience and the opportunity to discover their passion. From the article:

Palo Alto High School student Catherine Yu [pictured to the right], for example, is interning at the Stanford Blood Center in the immunology and pathology lab. She described her task as gathering data to help her supervisor’s research project.

“Every intern is assigned to a supervisor who is working on an experiment, which will hopefully be turned into a paper submitted for a journal,” said Yu, who will be a senior in September. “My work consists of separating blood into T cells, monocytes, dendritic cells, and then culturing them together; it’s very neat.”

Yu said being the only high school student in her lab presents her with a series of challenges.

“It’s definitely a different dynamic where they expect you to learn a lot of information at a very fast pace,” Yu said. “I have to stay on my toes so I don’t fall behind.”

Previously: Internships expose local high-schoolers to STEM careers and academic life, Residential learning program offers undergrads a new approach to scientific inquiry, The “transformative experience” of working in a Stanford stem-cell lab and Stanford’s RISE program gives high-schoolers a scientific boost
Photo by L.A. Cicero

Scientist-moms out there might enjoy this playful (tongue-in-cheek) Huffington Post essay on how having a science degree made the writer a better parent. I had to chuckle at Sarah Gilbert’s list of how she’s found uses for the sciences in her day-to-day life:

Physics: Knowing that my house will return to complete disorder immediately after I clean it, because entropy.

Biology: Knowing everything my baby ate by the contents of her diaper, because scat identification.

Neuro-psychology: Knowing that my toddler freaking out over sandwich crusts is just a phase, because frontal lobe development.

…

Statistics: Knowing that the chance of having a baby brother is 50/50 no matter what my mother-in-law thinks, because mutually exclusive events.

Astronomy: Knowing that the woman judging me by my yogurt-spattered shirt isn’t the only thing in the universe, because cosmology.

Most biomedical research is focused on disease and specific treatments for illness, rather than on understanding what it means to be healthy. Now researchers at Stanford, in collaboration with Duke University and Google [x], are planning a comprehensive initiative to understand the molecular markers that are key to health and the changes in those biomarkers that may lead to disease. The was featured in a Wall Street Journal article today.

The study is at the very early stages, with researchers planning to enroll 175 healthy participants in a pilot trial later this year. The participants will undergo a physical exam and provide samples of blood, saliva and other body fluids that can be examined using new molecular testing tools, such as genome sequencing.  The pilot study will help the researchers design and conduct a much larger trial in the future.

“We continue as a global community to think about health primarily only after becoming ill,” Sanjiv Sam Gambhir, MD, PhD, professor and chair of radiology, told me. “To understand health and illness effectively, we have to have a better understanding of what ‘normal’ or ‘healthy’ really means at the biochemical level.”

“The study being planned will allow us to better understand the variation of many biomarkers in the normal population and what parameters are predictive of illness and may eventually change as a given individual transitions from a healthy to a diseased state. This will be a critical study that will likely help the field of health care for decades to come,” said Gambhir, who also directs the Canary Center at Stanford for Cancer Early Detection.

The researchers hope the work will provide insights on a variety of medical conditions, such as cancer and heart disease, and point to new methods for early detection of illness. Their studies will focus on the genetic basis of disease, as well as the complex interplay between genes and environment.

These kinds of studies haven’t been done before because of the cost and complexity of molecular measurement tools, the scientists say. However, the cost of some technologies, such as DNA sequencing, has been steadily declining, while some new tools and new ways of analyzing large quantities of data have just recently become available. So a first step in the study is to determine how best to use these technologies and determine what questions need to explored on a larger scale.

The work is sponsored by Google [x] and will be led by Andrew Conrad, PhD, a cell biologist and project manager at the company.

Californians, step away from the beach and grab a hat and sunscreen. Our team of researchers from the Cancer Prevention Institute of California/Stanford Cancer Institute released a new report (.pdf) this week documenting the rapidly growing burden of melanoma in Marin County, Cali. This small, homogenous (and wealthy) county just over the Golden Gate Bridge from San Francisco has been the focus of cancer studies before, as high rates of breast cancer were first reported there in the late 1990’s (rates declined there as in the rest of the country in 2003 when women stopped taking hormone therapy).

Our most recent cancer registry data show that rates of malignant melanomas in Marin County are 43 percent higher than the rest of the San Francisco Bay Area and 60 percent higher than other parts of California among non-Hispanic whites, who because of their fairer skin tones are diagnosed with melanoma at 20-30 times the rate of other ethnic groups. Also of concern is that the death rate due to melanoma is 18 percent higher in Marin whites than whites in other regions, a significant difference not seen before. Most of the elevated rates are limited to persons over age 65, especially men.

The Bay Area news media reported our findings as front-page news. Most coverage centered on the question of why the rates are so much higher in Marin County. Our best guess is that the higher average socioeconomic status of its residents corresponds to a higher proportion of people with the known risk factors for melanoma: fair complexion (pale skin, blonde or red hair, blue or green eyes) and a history of “intense intermittent” sun exposure over their lifetimes (exposure in big doses like you might get on a beach vacation in the winter).

However, it is also likely that better access to health care and skin screening has resulted in earlier diagnosis, a notion confirmed by the higher proportion of melanomas in Marin County caught when thin and more curable. Local dermatologists reacted to the statistics with some surprise, but didn’t change their standing advice regarding skin cancer prevention: talk to your doctor about skin screening and stay sun safe by wearing hats, long-sleeves and broad-spectrum sunscreen during outdoor activities.

One statistic mostly overlooked by the media was our finding that melanoma is now the second most common cancer diagnosed in men living in Marin County, as rates have surpassed those for lung cancer. This pattern is very different than that observed for whites in the US and world, for whom prostate or lung are first, and melanoma is ranked much lower. With one of the most successful public tobacco control efforts in the world, most populations in California have seen rapid declines in the incidence of smoking-related cancers of the lung and respiratory system.

Unfortunately, it seems for older white persons in Marin County (as well as parts of Utah and Hawaii, where smoking rates have also declined), melanoma and skin cancers represent a major—and relentlessly growing—cancer threat. Perhaps putting down the cigarettes was accompanied by more time at the pool or beach without adequate sun protection. Although California was the first state to ban tanning bed use by minors, we should look to Australia and other countries also battling rising skin cancer rates for innovative new policies and strategies for encouraging safe sun exposure in our at-risk communities.

Christina A. Clarke, PhD is a Research Scientist and Scientific Communications Advisor for the Cancer Prevention Institute of California, and a member of the Stanford Cancer Institute.

Previously: Beat the heat – and protect your skin from the sun, Working to protect athletes from sun dangers, As summer heats up take steps to protect your skin, Stanford study: Young men more likely to succumb to melanoma and How ultraviolet radiation changes the protective functions of human skin
Photo by stefan klocek

Previous research has shown that regularly drinking coffee could offer a number of health benefits, including reducing prostate cancer risk, improving symptoms related to Parkinson’s disease, staving off the development of Alzheimer’s, decreasing diabetes risk and providing antioxidants.

But too much caffeine can make you jittery, disrupt your sleep and, potentially, shorten your life span. So it’s often recommended that you drink coffee in moderation, which is defined as two or three eight-ounce cups of brewed or drip coffee.

The problem with recommending a certain number of cups, reports Scientific American, is that new research shows the caffeine and caffeoylquinic acid (CQA) content can vary greatly depending on the type and preparation of the coffee. From the piece:

Results showed that the caffeine-to-CQA ratio in espressos ranged from 0.7–11, depending on the preparation conditions. With serving volumes from 13–104ml, it’s no wonder that Crozier says ‘cup of coffee is an exceedingly variable unit. To estimate health benefits using cups may be very difficult,’ – and inadvisable in epidemiological studies.

But what are CQAs? Beans contain various (poly)phenols, including 3-, 4- and 5-O-caffeoylquinic acids, the main phenolic compounds in coffee. Epidemiological studies have suggested the link between the lower risk of type 2 diabetes, cardiovascular diseases, and endometrial and hepatocellular cancer in habitual coffee consumers might be due to the presence of CQAs in coffee. They sound like super-compounds, but that’s a big ‘might’, and research continues.

Whilst the biological effects of CQAs are uncertain, one thing we do know about them is they are more sensitive to roasting than caffeine. The bean or blend also affects the caffeine-to-CQA ratio. Arabica and Robusta are the most common bean types and the latter contains twice as much caffeine as the former.

The article highlights the need to better inform consumers about the actual amount of caffeine in coffee and the need for more research on the health benefits of coffee.

Previously: How the body’s natural defenses help protect cells from toxins in everyday foods and flavorings, What is coffee?, For new moms, coffee scores a point: Caffeine doesn’t seem to interfere with baby’s sleep in study and Does coffee lower the risk of prostate cancer?
Photo by Nina Matthews

When it comes to diagnosing disease and choosing a course of treatment, gender is a significant factor. In a Stanford BeWell Q&A, Marcia Stefanick, PhD, a professor of medicine at the Stanford Prevention Research Center and co-director of the Stanford Women & Sex Differences in Medicine Center, discusses why gender medicine research benefits both sexes and why physicians need to do a better job of taking sex difference into consideration when make medical decisions.

Below Stefanick explains why a lack of understanding about the different clinical manifestations of prevalent diseases in women and men can lead to health disparities:

…Because we may have primarily studied a particular disease in only one of the sexes, usually males (and most basic research is done in male rodents), the resulting treatments are most often based on that one sex’s physiology. Such treatments in the other sex might not be appropriate. One example is sleep medication. Ambien is the prescription medicine recently featured on the TV show, 60 Minutes. Reporters found out that women were getting twice the dose they should because they had been given the men’s doses; consequently, the women were falling asleep at the wheel and having accidents. Physicians had not taken into account that women are smaller and their livers’ metabolize drugs differently than do men’s. Some women have responded by reducing their own medication dosages, and yet that practice of self-adjusting is not the safest way to proceed, either.

Previously: A call to advance research on women’s health issues, Exploring sex differences in the brain and Women underrepresented in heart studies
Photo by Mary Anne Enriquez

One in four adults in the United States has two or more chronic conditions, according to the latest data from the Centers for Disease Control and Prevention. And, findings published in the August issue of Medical Care show that the burden of multiple chronic diseases could explain why life expectancy increases among elderly Americans are slowing.

In the study (subscription required), researchers at Johns Hopkins Bloomberg School of Public Health analyzed a nationally representative sample of 1.4 million Medicare beneficiaries. According to a release:

The analysis found that, on average, a 75-year-old American woman with no chronic conditions will live 17.3 additional years (that’s to more than 92 years old). But a 75-year-old woman with five chronic conditions will only live, on average, to the age of 87, and a 75-year-old woman with 10 or more chronic conditions will only live to the age of 80. Women continue to live longer than men, while white people live longer than black people.

It’s not just how many diseases you have, but also what disease that matters. At 67, an individual with heart disease is estimated to live an additional 21.2 years on average, while someone diagnosed with Alzheimer’s disease is only expected to live 12 additional years.

On average, life expectancy is reduced by 1.8 years with each additional chronic condition, the researchers found. But while the first disease shaves off just a fraction of a year off life expectancy for older people, the impact grows as the diseases add up.

Previously: Americans are living longer, but are we healthier in our golden years?, Longevity gene tied to nerve stem cell regeneration, say Stanford researchers, Study shows regular physical activity, even modest amounts, can add years to your life and TED Talk with Laura Carstensen shows older adults have an edge on happiness
Photo by Marcel Oosterwijk

A few nights after the recent plane crash in Ukraine, I ran into an acquaintance who was heading to Europe later in the week. “It feels weird to fly,” she told me, comparing it to how she felt about boarding a plane for the first time after the 9/11 attacks 13 years ago. I could relate: During my first post-9/11 flight, I was jittery and uneasy the entire way from San Francisco to Minneapolis. (It didn’t help that I was flying alone, in the darkened cabin of a red-eye.)

If plane crashes and tragedies like the one in Ukraine can leave passengers feeling unsettled (or worse), how might they affect people who take to the skies on an almost daily basis? In a piece on The Atlantic yesterday, writer Rebecca Rosen reported on the work of Jeffrey M. Lating, PhD, a professor of psychology at Loyola University Maryland who has studied this issue. Rosen writes:

For flight attendants who worked at American Airlines on 9/11, the rates [of PTSD] were… just over 18 percent. This number is so high, Lating says, it is comparable to the rates seen among people living south of Canal Street in Manhattan, the neighborhoods closest to Ground Zero.

Lating and his colleagues found no statistical difference in probable PTSD rates between West Coast flight attendants and East Coasters, who were much more likely to have known the flight attendants killed on 9/11. For flight attendants, it seems that the trauma they experience following a crash comes not only from the loss and tragedy itself, but also from a deep sense of vulnerability. A follow-up study in 2006 found similarly high rates of probable PTSD at another airline, further suggesting that “it didn’t matter what airline you worked for,” says Lating. “The virulent factor in this was, ‘I wonder if I could possibly be next.’ ”

…

Those fears can make just doing one’s job as a flight attendant incredibly challenging. Many suffering from PTSD try to avoid sights and triggers that recall the initial trauma. But for flight attendants, those reminders are unavoidable, part of the work itself. To have to work through that anxiety, all the while servicing others and maintaining a sense of calm on a flight— “you could imagine how uncomfortable that would be,” Lating say

Previously: 9/11: Grieving in the age of social media and What 9/11 has taught us about PTSD
Photo by epsos.de

Given the topic of today’s SMS-Unplugged entry, during which Moises Humberto Gallegos discusses how things like housing insecurity and financial hardship can contribute to poor health, I was interested to come across this Covering Health quiz on the social determinants of health. Writer Joe Rojas-Burke asks 10 true-or-false questions, and I think some of the answers may surprise you. For example:

Expanding health insurance coverage and access to medical care (the focus of the federal Affordable Care Act) is unlikely to reverse the health disparities caused by the social determinants of health.

TRUE: In countries that established universal health coverage decades ago, lower social status still correlates with worse health and shorter lives. The research on social determinants suggests that progress is likely to require broader social changes, such as improving access to education, boosting economic opportunity and making disadvantaged neighborhoods safer and and more vital.

And:

Food deserts – neighborhoods with few or no grocery stores selling fresh, affordable produce – are a well-defined root cause of obesity and other health problems in disadvantaged communities.

FALSE: There is evidence showing that low-income and minority Americans are more likely to live in food deserts. But it’s not at all clear to what extent the lack of supermarkets and grocery stores contributes to obesity or other health outcomes.

Previously: In medicine, showing empathy isn’t enough, Should the lack of access to good food be blamed for America’s poor eating habits? and Hopkins researchers find place, rather than race, may be greater determinant of health