The Decision Tree

Archive

Archive for the ‘disease management’ Category

Sharing data on social media

September 26th, 2011 Comments off

facebook like button By Sean MacEntee, http://www.flickr.com/photos/smemon/5684115572/

People use Facebook, Twitter, or other social media sites as channels for self-expression. But whether updating or uploading, people are telling their social stories with only two tools: text and images.

But what if social media wasn’t confined to words and pictures, but instead, allowed users to uploaded graphs or tables? In other words, could data, pure data, become a token in our social currency?

Read more…

Share

Storm Surge

September 5th, 2011 4 comments

Temple in the rain @ China By Yorick_R, http://www.flickr.com/photos/yorickr/5905162253/

The idea that climate change is linked to the spread of a disease is not new. Some bacteria and viruses, after all, piggyback on an animal or insect, and the infectious advance depends on the host’s reaction to climbing temperatures. Consider dengue, a disease once anchored to tropical climates by its host’s penchant for heat and humidity, which is now pushing further north with its mosquito transits as the upper latitudes get warmer. But according to a study published this past June in PNAS, it’s not only climbing temperatures that are worrisome; in the past, even heavy rains have altered the course of disease, though often in divergent directions.

During the third plague pandemic (China, 1850-1964), researchers found that, for better or worse, the seasonal rains were a strong predictor of how the disease spread. There, storms governed Pestilence’s toll, prodding the disease in the arid north, and quelling it in the humid south.

Rats are the primary host for the bubonic plague, and in general, the more that infected rats move, the more the disease will spread. In the dry north, they figure, the rains quenched the parched landscape, causing the rats, and the disease, to stir. In the southern part of the country, the rains only served to make the humidity worse, perhaps forcing the rats to sit tight.

Keeping tabs on the spread of infectious disease is one thing; understanding the interaction of pathogens, hosts, and behavior is yet another.

Photo via Flickr / Yorick_R

Share

The New Face of Addiction: Prescription Painkillers

August 24th, 2010 Comments off

The Washington Post reports that nearly 21% of Americans, aged 12 and older, have used prescription medication for non-medical reasons.  At the same time, we’ve seen more than a four-fold increase in the number of prescriptions handed out for opiate painkillers (like Percocet, Vicodin, and Oxytocin).

Why are these drugs becoming more popular than illicit street drugs?  The Post article cites two reasons.  First, these drugs are available.  Users will often shop around for doctors who will provide them with extra pills with minimal hassle.  Second, there is a common misconception that these pharmaceuticals are less dangerous or addictive than street drugs.  But the reality is, they activate the same opioid receptors as heroin.

Simply cracking down the amount of drugs handed out isn’t the solution.  Neither is making sweeping modifications that make it harder to get these drugs.  Many chronic pain patients rely on these medications to function, and their quality of life might suffer because of the irresponsible use of others.

It seems patient education is currently the best system for preventing addiction and abuse of prescription painkillers.  Every time another prescription for these medications is torn from a doctor’s tablet, a serious conversation about the proper use and risks of abuse should follow.

Share

New Biomarkers for Diabetes

April 14th, 2010 Comments off

Obesity (determined by BMI) and blood glucose levels are by far the best predictors of whether a person will develop diabetes. Yet doctors are always on high alert for new biomarkers that may be more sensitive indicators of which patients will develop diabetes in the near future.

The idea of using biomarkers to predict diabetes is not entirely new. Glycated hemoglobin (HbA1C) values are now routinely being monitored to screen for at-risk patients. However, a new study in PLoS One shows that several new biomarkers in the blood may further our understanding of exactly who’s at risk for diabetes, and increase our knowledge of the etiology of the disease.

Veikko Salomaa and colleagues from the Department of Chronic Disease Prevention at the National Institute for Health and Welfare in Helsinki, Finland, tested nearly 13,000 people and found almost 600 cases of diabetes during routine follow-up exams.

According to the study, low levels of adiponectin, and high levels of apoB, C-reactive protein (CRP), and insulin, increase the chance that a woman will develop diabetes. When these factors were measured, proper diabetes prediction increased by 14% compared to when doctors only use classic risk factors, such as BMI and blood glucose levels, to predict disease.

The biomarkers that best predicted diabetes in men were low adiponectin, and high levels of CRP, interleukin-1 receptor antagonist, and ferritin. Accounting for these biomarkers led to a 25% increase in correct diabetes detection in the cohort.

read the study here.

Share

Screening HPV at Home

March 16th, 2010 Comments off

In Chapter 6 of The Decision Tree, “Screening for Everything”, Thomas talks about the human papilloma virus (HPV), the virus that causes cervical cancer. Traditionally, doctors detected HPV by looking for irregular cells in the pap smear. But now, a cheap ($5) test can detect and analyze the DNA of the virus, determining if it is the high- or low-risk type, which can determine the likelihood of a patient developing cervical cancer.

One problem remains: you still have to get women into the clinic to be tested. However, a new study in the British Medical Journal shows that home testing is not only a reality, but it may actually boost compliance rates. Roughly 28% of women using the home testing kit, which consisted of a simple cervicovaginal lavage, effectively screened themselves, while only about 17% of women required to go into the doctor’s office for screening showed up.

The HPV DNA test is primarily looking for the high-risk virus serotype, and the authors of this study claim that home screening kits have the same sensitivity as the doctor’s protocol when specifically looking for the aggressive virus.

Special thanks to Lindsay Crouse for bringing this to my attention. In her email to me, she brilliantly summed up the significance of home HPV testing:

While screening has been tremendously successful in Western countries at reducing cervical cancer cases and deaths, the obstacle of reaching all women through screening remains. Currently, if a woman is to be screened for cervical cancer, she must visit a health care provider for a gynecological exam. If she is unable or reluctant to do that, whether due to transportation, cost, or comfort issues, she is less likely to get screened at all, and is consequently at increased risk for developing cervical cancer. More than half of such cancers are typically diagnosed in women who do not get screened regularly.

Share

Sugar-coated Laziness

March 10th, 2010 Comments off

Check out this study.

Researchers found that when “teenage” rats (30-45 days old) consumed massive amounts of sugar, they became extremely difficult to train as adults. For two weeks or so during adolescence, one group of rats had free access to a tasty 5% sucrose solution, while the control group only had water available. Similar to some American teenagers, the experimental group of rats consumed about 20% of their daily caloric intake as simple sugar.

To give you some background, it’s extremely easy to train adult rats to perform simple tasks, such as pulling levers or pressing buttons in return for a food reward. However, the researchers couldn’t motivate the rats that had consumed large amounts of sugar as teenagers to learn the task. My first reaction while reading this paper was: “Big deal. That group of rats just had sugar overload. It no longer had any real value for them, so there was no incentive to learn the new task”.

But here’s where the story gets interesting: if you repeat the experiment, but replace the teenage rats with adult rats, you get strikingly different results. When adult rats have free access to a sugary drink for two weeks, they never lose motivation for the sweet reward, and easily learn the new lever-pull task later in life. So it’s not that rats are simply sick of the sweet reward, but rather, it seems the sweet drink over-stimulated the reward pathway in the brain during adolescent development, leading to problems with motivation in adulthood.

Were the calories in the sugary drink or the sweet taste to blame for hyper-activating the reward circuits in the brain? To answer this, the authors took another group of teenage rats and gave them free access to a drink flavored with artificial sweetener, which has no calories. These rats were also unmotivated and rather difficult to train later in life, so the authors concluded that the sweet taste, but not the sugar itself, was hyper-activating the brain’s reward circuits.

Besides, ahem, crazy neuroscientists writing for health blogs, who cares about lazy rats? Well, the authors argue that a sign of depression in rodents is lack of motivation to perform simple tasks. Given that incidence rates for depression and other psychological illness are increasing in today’s society, it’s interesting to see how seemingly benign events during adolescence — a critical time in brain development — affect the mental state of adult animals.

Share

The Truth About Cholesterol

March 9th, 2010 Comments off

We’ve all heard the mantra: keep LDL levels – the “bad” cholesterol – down, and the “good” HDL cholesterol up. But thanks in part to the ubiquity of statins, such as Lipitor, which allow us to simply pop a pill to limit LDL production in the body, we’ve recently adopted tunnel vision when thinking about managing cholesterol. LDL levels are all we seem to care about now, as we strive for lower and lower numbers at each visit to the doctor’s office.

However, I think we’re missing the bigger picture by focusing solely on LDL. First, it’s made us reliant on medication to solve a problem that can many times be addressed with changes in diet and exercise regimes. Once someone starts Lipitor treatment, they’ll be taking it for life, and if LDL levels don’t quite get as low as they should, it’s all too easy to solve the problem by increasing the dose. When patients first begin Lipitor treatment, physicians typically prescribe the lowest possible amount, 10mg. However, dosing can go as high as 80mg, which begs the question: Do higher doses of the drug really improve outcomes?

Read more…

Share

Can High Blood Glucose Levels Cause Cancer?

February 19th, 2010 Comments off

Diets high in simple sugars and refined carbs cause metabolic disorders and Type II diabetes in millions of Americans. But to make matters worse, new evidence suggests that high sugar diets may be even more dangerous than we initially thought.

Having too much excess sugar in the bloodstream is never a good thing, and can lead to medical complications such as kidney failure, cardiovascular disease, and eye problems. But could high blood sugar also cause cancer? A Swedish research team addressed this question by tracking over 500,000 patients for 10-25 yeas, and published their results in the December issue of PLoS Medicine.

Similar to the findings of a study conducted in Korea in 2005, the European research team discovered that having elevated blood glucose levels increased the risk of developing certain types cancer later in life, such as pancreatic tumors in women and liver tumors in men. Not only had more cases of cancer occurred when people had high blood sugar, but the chance of survival also plummeted, especially when the person had cervical, espohageal, or colorectal cancers.

The authors present two theories on why elevated blood glucose levels could cause cancer: 1.) high sugar diets may cause an overproduction of insulin or insulin-like growth factor 1 (IGF-1), both of which promote rapid growth of new cells, the catalyzing step to tumor formation. 2.) More glucose in the blood stream could simply be adding fuel to the fire, feeding rogue tumor cells that need lots of energy to run.

Because the studies lacked certain controls, we can’t say for sure whether elevated blood glucose levels cause certain tumors to form. For example, the people with high blood glucose levels may have been sedentary, and so the lack of exercise may be what’s actually increasing the chances of developing cancer. Regardless, this study gives yet another example of unhealthy lifestyles contributing to comorbidity, a topic discussed at length by Thomas in The Decision Tree book.

Share

A Microbial Census

January 20th, 2010 2 comments

One morning, a little over a year ago, I woke up with a very sore, and slightly swollen elbow. I remembered that I had cut my arm on a neighborhood bar table while watching a football game with some friends a few days prior, and I wondered if the cut was infected. I made an appointment with my primary care physician, who quickly diagnosed me with bursitis, an inflammation of the fluid-filled sac that pads the elbow. Since I had broken skin, the doctor wisely prescribed clindamycin, an antibiotic, to treat any tissue infection that may have seeped in.

As the hours crept by, the pain in my elbow worsened, until I woke up in the middle of the night with extreme arm pain. I immediately checked the elbow that had been swollen the previous day. The swelling had doubled in size, and the skin was an angry-red color. The following morning, I was back in the clinic, and my doctor started to suspect that this was no ordinary infection on my elbow, and may in fact be a drug-resistant staph infection. Gulp. Nonetheless, he felt confident that the clindamycin should clear it up.

Read more…

Share

How “The Science of Success” Redefines Psychology

December 1st, 2009 Comments off

I just finished reading Dave Dobbs’ new article in the the December issue of The Atlantic, “The Science of Success”.  Dobbs turns the classic question of Nature vs. Nurture, whether our genes or our environment are the deterministic drivers of our fate, on its head.  Traditionally, those who support “nature” say that our genes are most influential in defining us.  On the other hand, those that support the “nurture” side say that our environment plays a more important role.

Based on new research, Dobbs introduces the idea of two types of people, “dandelions” and “orchids”.  Dandelions can thrive anywhere, despite their environment or upbringing.  Orchids, however, are more temperamental, and require a stable environment to survive.  At first glance, the orchids may seem like a liability, and in fact, they often carry genes that make them susceptible to mood disorders and psychological disease.  The astounding part of Dobbs’ report is that he shows that given the right care, or environment, the orchids don’t just do OK, but far surpass the dandelions in perfomance.  In other words, given the right training, orchids may in fact be destined for greatness.

This finding redefines conditions we typically may have classified as undesirable.  ADHD, depression, and generalized anxiety disorder, are no longer conditions to dread, because given the right training, people with these predispositions may in fact be the true “movers and shakers” in the world.

Please read the full article for yourself.  And, as always, I’d welcome a discussion here…

Share