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The next challenge for biodesign: constraining health-care costs

The next challenge for biodesign: constraining health-care costs

This post is part of the Biodesign’s Jugaad series following a group of Stanford Biodesign fellows from India. (Jugaad is a Hindi word that means an inexpensive, innovative solution.) The fellows will spend months immersed in the interdisciplinary environment of Stanford Bio-X, learning the Biodesign process of researching clinical needs and prototyping a medical device. The Biodesign program is now in its 14th year, and past fellows have successfully launched 36 companies focused on developing devices for unmet medical needs.

5445002411_0f22229afd_z 300Founder and director of the Stanford Biodesign Program Paul Yock, MD, describes himself as a “gismologist.” His inventions include a balloon angioplasty system that is in widespread use and many other devices primarily related to ultrasound imaging of the vascular system. I recently spoke with him about the program he helped found, the iterative biodesign process, and the ongoing relationship with the Stanford-India Biodesign Program.

What’s next for the Stanford Biodesign Program?

We’ve been really pleased with the results of the Biodesign Program so far in terms of being able to take newcomers into the process, then repeatedly and reliably seeing good ideas coming out and seeing patients getting treated from those good ideas.

The challenge is that the world has changed profoundly since we founded this program. There’s no question that new technologies – despite being good for patients – contribute to escalation of health-care costs. We are in a phase of reinventing our process to take into account the fact that the sickest patient in the system is the system itself. We have to invent technologies that help constrain costs. We will need to modify the process of needs-finding not only to look for important clinical needs but important value needs as well. Inventors in general don’t like thinking about economics and so we have to not only figure out how to update the process but also figure out how to make it attractive for our fellows to learn and practice.

Could the India fellows help you incorporate affordability into the process?

One of the big reasons we decided to do the India program in the first place was to shock our system into thinking about really affordable technology innovation. It is remarkable how good our fellows from India are at thinking this way and how immersed they have been from an early age with value-based design and invention.

Affordability is very much a part of the Indian culture and technology innovation is clearly something that we are very good at here. I think we have only started to capitalize on the fusion of their culture and ours. I think there is a hybridization here that really is going to be cool. Our grand strategy is to have a number of different platforms – it could be companies, incubators, or other experiences – where our fellows can get a deep exposure in India. We aren’t fans of parachuting people in for two weeks to invent something good to give to India. What we really want to do is have trainees get a deep experience in what it’s like to invent and develop technologies in that setting to influence the way we invent here.

How did you arrive at the drawn out, iterative process the fellows use to identify medical needs they want to address?

There’s a long tradition of what is called user centered design that says if you want to design a product you need to talk to the user and understand what their needs are. That’s essentially where our process starts. What’s fundamentally different with health care is that there isn’t just one user. There’s this really complex network of stakeholders who influence whether a technology will actually make it into patient care. You can’t just design for the patient because there are also the doctors, nurses, hospitals, insurance companies, regulatory agencies and financers to name a few. To make it all still more complex, this whole system is in tremendous flux because of health-care reform.

So what we’ve done is blow out the needs characterization stage to take all these stakeholders into account in a rigorous way, up front, before any inventing happens.  There’s also a bit of psychology at play here. In health care it is really easy to fall in love with the first need that comes your way. Looked at in isolation, pretty much any clinical need looks compelling. You need to put in a disciplined process, a semi-quantitative way of weighing one need against the other in order to make a good decision about which need to pursue. It is easier to get rid of the one you thought you loved if it really doesn’t meet the criteria you set out.

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Ask Stanford Med, Global Health, Stanford News, Technology

Stanford-India Biodesign co-founder: Our hope is to “inspire others and create a ripple effect” in India

Stanford-India Biodesign co-founder: Our hope is to "inspire others and create a ripple effect" in India

This post is part of the Biodesign’s Jugaad series following a group of Stanford Biodesign fellows from India. (Jugaad is a Hindi word that means an inexpensive, innovative solution.) The fellows will spend months immersed in the interdisciplinary environment of Stanford Bio-X, learning the Biodesign process of researching clinical needs and prototyping a medical device. The Biodesign program is now in its 14th year, and past fellows have successfully launched 36 companies focused on developing devices for unmet medical needs.

shutterstock_258773231Rajiv Doshi, MD, is the executive director (U.S.) of the Stanford-India Biodesign Program and was part of the Stanford team that initially flew to India in 2007 to propose the program to the Government of India. He has commercialized devices to treat sleep apnea and snoring and later served on boards of multiple medical device companies. In 2012 he was named by Forbes India as one of the top 18 Indian scientists who are changing the world.

Doshi answered questions about the early days of the Stanford-India Biodesign program and the hurdles entrepreneurs face in India.

Why did you want to start the Stanford-India Biodesign program?

Starting the program was both an opportunity and an obligation. My belief was that this was going to be a difficult challenge spanning perhaps a decade. We were working with a partner [the Indian government] where we didn’t know the people very well and we didn’t know many of their systems. We had never assembled such an international collaboration of this scale. If we failed then at least we tried and did our best. If we were successful then we would have helped a lot of people. I felt that this was a once in a lifetime opportunity to have an impact of this scale.

What were some of the hurdles the early fellows faced when they tried to develop technologies in India?

Probably the number one problem they face in India is that there is really little mentorship as we know it here. Few people in India have successfully developed a medical device from scratch so it is really hard to find mentors who are already domain experts in medical technology. The next issue is raising capital. There is very little early stage venture capital focused on medical technology in India.

Then there are challenges with research and development. Imagine you’re creating a difficult-to-make medical device that has small, complicated parts. Odds are the suppliers aren’t available for all these parts in India. Then there’s manufacturing and supply chain issues. Let’s say the entrepreneurs are able to develop a product, then they may struggle to find an in-country manufacturer to make this product. In many cases, in-country manufacturing capabilities just aren’t at the same level as you would see here or in Singapore, Germany or other locations. So you start stacking these challenges together and you realize that they are pretty serious.

Does it get easier once they’ve developed the device?

No, I think the greatest challenges are related to commercialization – after development has been completed. Let’s imagine you created a great product, you’ve figured out all these issues. Your next challenge is then to market your product and convince healthcare providers in India to start using your product. This takes time and money to support your marketing and sales efforts. Additionally, many of the providers may not be as trained as their US or UK counterparts and may be less likely to adopt your product if it requires a certain level of training. Finally, there is the issue of who is going to pay for the product. In India, only about 25 percent of people have basic health insurance so any device in India needs to be quite low cost to be broadly used.

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Ask Stanford Med, Cardiovascular Medicine, Events, Genetics

A conversation about using genetics to advance cardiovascular medicine

A conversation about using genetics to advance cardiovascular medicine

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In recognition of American Heart Month, Stanford Health Care is hosting a heart fair on Saturday. The free community event includes a number of talks ranging in topic from the latest developments in treating atrial fibrillation to specific issues related to women’s heart health.

During the session on heart-disease prevention, Joshua Knowles, MD, PhD, will deliver a talk titled “How We Can (and Will) Use Genetics to Improve Cardiac Health.” Knowles’ research focuses on familial hypercholesterolemia, a genetic disease that causes a deadly buildup of cholesterol in the arteries. He and colleagues recently launched a project that uses a big-data approach to search electronic medical records and identify patients who may have the potentially fatal heart condition.

To kick off the conversation about preventing heart disease, I contacted Knowles to learn more about how the genomics revolution is changing the cardiovascular medicine landscape and what you can do to determine if you have a genetic heart disorder. Below he explains why heart disease is a “complex interplay between genetics and environment” and what the future may hold with respect to personalized treatments and pharmacogenetics.

Let’s start by talking about your work on familial hypercholesterolemia (FH). How has the understanding of the genetic basis of FH evolved over the last few years, and what key questions remain unanswered?

For FH, there has been a revolution in our understanding. FH causes very elevated cholesterol levels and risk of early onset heart disease. We used to think that it affected 1 in 500 individuals, but recent studies have pointed out that this is probably an underestimate and it may affect as many as 1 in 200 people. This means that there may be as many as 1 million people in the United States who are affected. We have also identified new genes that cause FH, and the identification of some of these genes has directly translated into the development of a new class of drugs (so called PCSK9 inhibitors) to treat this condition.

What steps can patients take to determine if they are at risk of, or may have, a genetic cardiovascular disorder like FH?

The easiest way is to know about your family history of medical conditions- to know what illnesses affected parents, grandparents, uncles, aunts and other relatives. Of course, genes aren’t the only things that are passed in families. Good and bad habits, such as exercise patterns, smoking and diet, are also passed down through the generations. But a family history of heart disease or certain forms of cancer is certainly a risk factor.

Past research suggests that patients with a genetic predisposition to heart disease can significantly reduce their chances of having a heart attack or stroke by making changes to their lifestyle, such as eating a diet rich in fruits and vegetables. Can lifestyle changes overcome genetics?

Heart disease is a result of the complex interplay between genetics and environment – lifestyle, for instance. For some people with specific genetic conditions, such as familial hypercholesterolemia or hypertrophic cardiomyopathy, the effect of genetics tends to dominate the effect of environment because the genetic effect is so large.

For the vast majority of people without these “Mendelian” forms of heart disease, which follow the laws of inheritance were derived by nineteenth-century Austrian monk Gregor Mendel, it’s difficult to determine at an individual level how much of the risk is due to genes and how much is due to environment (this is for things like high blood pressure, high cholesterol, coronary disease). One clue is certainly family history. However, for most of these diseases the genes are not “deterministic” – that is, people are not destined to have these diseases. Some are more at risk than others, but there are certainly ways to mitigate genetic risk through lifestyle choices. Choosing not to smoke and exercising regularly are two examples of ways you can help to greatly minimize genetic risk.

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Ask Stanford Med, Events, Nutrition, Obesity, Stanford News

Sticky situation: How sugar affects our health

Sticky situation: How sugar affects our health

132244825_dbf0e21d9f_zHere’s a shocking statistic: On average, Americans consume three pounds of sugar each week, or 3,550 pounds in an entire lifetime. This leads some to blame the sweet stuff for the increase of chronic disease in modern society. But simply reducing our sugar intake is easier said than done, in part because identifying foods with added sugars can be tricky.

This Thursday, Alison Ryan, a clinical dietician with Stanford Health Care, will deliver an in-depth talk on sugar and our health as part of a Stanford Health Library lecture series. Those unable to attend can watch the presentation online here.

In the following Q&A, Ryan discusses the controversies surrounding sugar and the role of sugar in our diet, and she offers tips for making sure your consumption doesn’t exceed daily guidelines.

Why does our body need sugar?

Sugar, in the form of dextrose or glucose, is the main fuel or energy source for the cells of the human body. Without glucose, our body has to get creative and rely on other metabolic pathways, like ketosis, to keep our brain and other organs running. There is an optimal range for our blood sugar levels, and our bodies are making constant efforts to keep blood sugar within this range.

Our body can make glucose from any carbohydrate that is consumed, so consuming monosaccharide (glucose and the like) is not biologically required. This is one of the reasons it’s difficult to determine the right amount of sugar that is required for the human body. Do we think of the optimal amount as the amount needed to function at peak level? Or an amount not to go over in order to avoid detrimental effects on our health?

Sugar intake has been on the rise in human diets. Why do you think that is?

At one time, sugar used to be a seldom available food item. It is now ubiquitous and more of a hallmark for highly processed, low nutritional value foods. Now, consider the food industry and the politics of sugar. Soda companies, makers of desserts, cakes, sugary snack foods, the sugar and corn syrup refiners all lobby to keep their products “part of a balanced diet.” The food industry is deeply involved (or at least vocal about) the food and nutrition guidelines in the U.S. Then there’s the reality that sugar tastes good! Most people enjoy the taste of sweet foods and are drawn to consuming them.

What are some of the health risks of consuming too much sugar?

Sugar has been implicated as playing a role in some obvious ways, like obesity, diabetes, and tooth decay; but also in less direct appearing ways such as heart disease, chronic inflammatory conditions, cancer, etc. Often, when we’re consuming foods high in sugar, we’re not consuming foods that are rich in nutrients. These calorie-dense foods displace the nutrient-dense foods. The net effect is higher intake of calories, with concurrent lower intake of vitamins, minerals, phytonutrients, protein, etc.

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Ask Stanford Med, Health and Fitness, Nutrition, Obesity

How to keep New Year’s resolutions to eat healthy

How to keep New Year's resolutions to eat healthy

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New Year’s Day always offers the opportunity to hit pause, reflect on our lives and set goals to improve our health and well-being. For many of us, this year also involved making promises to eat healthier and lose weight. To help you achieve your nutrition goals, I reached out to Stanford health educator Jae Berman. Below she shares how to select New Year’s resolutions that you’ll actually keep (perhaps you’ll have to tweak the ones you made last week!), offers strategies for eating healthy even when you’re pressed for time, and explains why cooking for yourself is a key factor in changing nutritional habits.

What are some examples of smaller, more manageable, goals that could help someone make better food choices?

People often jump in too hard, too fast when creating New Year’s resolutions. This perfectionist and “all or nothing” attitude tends to result in grand, lofty goals that we quit if we have a setback or don’t see immediate results. When considering health and weight loss-related goals make sure they are realistic and sustainable.

Instead, closely examine your routine and note one thing you can improve. This behavior may be something obvious, such as you drinking soda every day and wanting to stop. Or, it could be an aspiration to make healthy habits more sustainable, for example, bringing your lunch to work so you can lose weight and save money. Those who already eat well and exercise regularly may want to adopt a goal on a larger scope and learn to cook or try a new form of exercise.

Pick one thing (just one!) and make sure it is SMART – specific, measurable, achievable, results-focused and time-bound. Pick a resolution that is within reach, yet a bit of a stretch so that it’s a challenge. Additionally, goals should lead towards creating a sustainable habit. Some ideas include: Bring your lunch to work Monday-Thursday for the entire month of January; eat five fist-sized servings of vegetables every day; drink coffee only at breakfast; go to sleep at at the same time every night and wake up at the same time every morning for the month of January; or do 30 minutes of weight training three times a week.

In an effort to slim down in the New Year, some individuals may go on the Atkins diet and other popular weight-loss plans, or decide to do a juice fast, like the Master Cleanse. What’s your advice for those considering these approaches?

It’s very difficult to change someone’s mind when they decide to try these types of weight loss plans. So I usually say, “Go for it!” After a few days, the person often feels miserable and wants to create a long-term plan for managing their weight. I will say the one benefit of these quick fixes and fad diets, which I do not endorse, is that they teach a person what it feels like to be hungry. This may sound strange, but this awareness is an important lesson.

Many people overeat and are used to eating to avoid being hungry. We also tend to mindlessly eat out of boredom, or simply because food is in front of us. Going on a restrictive diet results in some feeling hungry for the first time in long time and, as a result they learn their hunger cues. When you experience a hunger cue, which is right when you think “I could eat,” then you should eat just enough food to get through the next three to four hours. You don’t need a huge meal to feel stuffed and small; unsatisfying snacks aren’t helpful either. Understanding what it feels like to be satiated is very important for long-term success.

Ongoing research at the Stanford Prevention Research Center shows that “one diet really does not fit all.”  So I can’t tell you exactly what to eat, but I can tell you that creating a long-term sustainable plan is key.

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Ask Stanford Med, Chronic Disease, Nutrition

Diabetes and nutrition: Healthy holiday eating tips, red meat and disease risk, and going vegetarian

Diabetes and nutrition: Healthy holiday eating tips, red meat and disease risk, and going vegetarian

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Despite greater awareness about diabetes in recent years, a recent study found that nearly three in 10 Americans have the disease but don’t know it. The findings also showed that among those who were diagnosed with diabetes, a significant percentage weren’t meeting goals to control their blood sugar and blood pressure or lower their LDL cholesterol.

This Thursday, Kathleen Kenny, MD, a clinical associate professor at Stanford, and Jessica Shipley, a clinical dietitian at Stanford Hospital & Clinics, will discuss why eating healthy is a key component of diabetes management and prevention. The Stanford Health Library event will be held at the Arrillaga Alumni Center on campus; those unable to attend the event can watch a live webcast of the discussion.

In the final installment of our two-part Q&A with Kenny, she offers tips to avoid overindulging on sugary treats during the holidays, explains why you should consider limiting your consumption of red meat, and outlines the benefits of a vegetarian diet.

Many of us have a hard time refraining from indulging in high-calorie foods during the holidays. What’s your advice to those trying to make healthy choices during holiday season?

The holidays don’t have to be a stressful or trying time for patients with diabetes. Patients can adhere to a few simple strategies to help prevent weight gain and hyperglycemia. Some people will find it beneficial to eat a nutritious snack, particularly one that is high in fiber, and to drink lots of water in advance of a holiday party, rather than arriving hungry.

Buffet tables and appetizer trays can be problematic. Count toothpicks and stop snacking when you reach a certain number of toothpicks in your pocket. It is always a good idea to find the smallest plate available, when there are options, so as to reduce portions. Another tip is to limit alcohol intake; not only will this itself reduce liquid calories, but it will help individuals to make smarter choices. Substitute sparkling mineral water with lemon or lime. Eat lots of veggies at snack tables. Avoid calorie and sugar-dense sweets, or limit to one.

The most important aspect is to devise a plan in advance of a holiday gathering, and stick to it. Set your predetermined limits. Spontaneous choices will tend to be less healthy ones. Finally, if you are going to indulge a bit more, try to take a brisk walk afterwards to help reduce the glycemic impact of your meal.

Previous research has shown that decreasing your red meat consumption can lower your type 2 diabetes risk. Why does eating red meat influence a person’s diabetes risk? 

A study published in the Journal of the American Medical Association last year found an association of higher-diabetes risk with increased intake of red meat (about 30 percent higher with average increased red meat intake of ½ serving daily, adjusted for weight and BMI), and the converse, a lower risk in those who decreased their red meat consumption over a four-year period in the subsequent four years (14 percent reduction in diabetes risk by reducing consumption by more than ½ red meat serving daily over the baseline measure, some of which was mediated by reduced BMI with lower red meat intake).

This data was based on food questionnaires, and was a compilation from three prospective cohort studies involving almost 150,000 men and women. One of these cohorts, the Women’s Health Study, showed a 28 percent increased risk of developing diabetes in women in the highest quintile of red meat intake.  On further analysis, this seemed to be largely mediated by higher intake of processed meats such as hot dogs and bacon. Note that these studies do show an association, but not clear causation in terms of red meat and diabetes risk.

One theory of causality proposed is that compounds such as nitrates and nitrites added in meat processing  (sandwich meats, hot dogs, bacon), can be converted to “N-Nitrosamines”, which are thought to be toxic to the pancreas insulin-secreting beta cells. Thus, eating a bologna sandwich may be different in risk than eating grass-fed organic beef. But we don’t have enough data at this time to be clear on this.  Regardless of the nitrate content, red meat is still high in saturated fats, and this in and of itself is associated with higher cardiovascular disease risk. Additionally, higher red meat intake was associated with more weight gain and higher BMI in this analysis.

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Ask Stanford Med, Chronic Disease, Events, Nutrition

Diabetes and nutrition: Why healthy eating is a key component of prevention and management

Diabetes and nutrition: Why healthy eating is a key component of prevention and management

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The prevalence of type 2 diabetes is expected to rise sharply over the next three decades. Recent data from the Centers for Disease Control and Prevention shows that if current trends continue, an estimated 1 in 3 adults will be diagnosed with the disorder by 2050. Eating healthy is a key component of managing diabetes and reducing one’s risk for developing the disease. But what does eating right for diabetes actually mean?

Kathleen Kenny, MD, a clinical associate professor at Stanford, and Jessica Shipley, a clinical dietitian at Stanford Hospital & Clinics, will answer this question during a talk focused on diabetes and nutrition on Dec. 4. The Stanford Health Library event will be held at the Arrillaga Alumni Center on campus, where attendees can also have their blood glucose checked. The conversation will also be webcasted for those unable to attend in person.

To promote discussion on the topic in advance of the lecture, I reached out to Kenny and asked about nutrition principles and guidelines for patients with diabetes and others interested in how healthy eating can prevent or delay onset of the disease. In the first installment of a two-part Q&A, she explains the advantages of eating a Mediterranean diet and the importance of eating fiber-rich foods.

Are there any ways to reverse or slow the progression of pre-diabetes? Are there specific diets that may be useful to help prevent or control diabetes?

One of the most common questions my diabetic patients ask is how they can reduce or eliminate diabetes medications. Others are found to be pre-diabetic on the basis of an “A1c” or an impaired fasting glucose, and want to know how to prevent diabetes. Several randomized trials have shown that healthy diet and exercise can reverse and also delay the onset of diabetes.

One of the largest trials is the often-cited Diabetes Prevention Program, which randomized more than 3,000 patients to diet/lifestyle versus metformin versus placebo. The most effective strategy was diet and lifestyle, showing a dramatic 58 precent reduction in the rate of developing diabetes. This surpassed the drug therapy with metformin. Approximately 5 percent of patients in the lifestyle group developed diabetes annually, as compared to 11 percent in the placebo arm. Notably, there was a 16 percent reduction in diabetes risk with every 1 kg reduction in weight. This seems attainable for many patients.

There was also meta-analysis last year looking at different diets for patients with known diabetes, in terms of weight loss and improving their diabetes control. In this data compilation, the Mediterranean diet had the greatest weight loss, followed by the low carbohydrate diet. In terms of A1c reduction, the Mediterranean diet had a reduction of -0.47 percent, and the low carbohydrate -0.12 percent. But all the diets studied resulted in better glycemic control. Many studies have shown that diets high in glycemic load are linked to higher diabetes risk (particularly in overweight women), and contribute to central body fat , so it is recommended that diabetics or those at risk limit their intake of high glycemic index foods both to delay and to help control their diabetes. Additionally, there are some data suggesting that adherence and success rate may be higher for low-carbohydrate diets in patients with diabetes and insulin resistance.

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Ask Stanford Med, Chronic Disease, Events, Health and Fitness

Examining the role of exercise in managing and preventing diabetes

Examining the role of exercise in managing and preventing diabetes

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More than 29 million adults and children in the United States are living with diabetes, and it’s estimated (.pdf) that an additional 86 million Americans ages 20 years or older have prediabetes, putting them at increased risk of developing the disease.

The good news is that lifestyle modifications can be an effective method for managing or preventing diabetes. In recognition of National Diabetes Month, I reached out to Baldeep Singh, MD, a clinical professor at Stanford who focuses on chronic disease management, to discuss the importance of regular physical activity for patients diagnosed with diabetes and those working to limit their risk of developing the disease. This Thursday, Singh will explore the topic more in-depth during a Stanford Health Library event at the Arrillaga Alumni Center on campus, where attendees can also have their blood glucose checked. The discussion will also be webcasted for those unable to attend in person.

In this Q&A, Singh highlights scientific evidence showing that staying active has a beneficial effect on insulin sensitivity, and discusses the potential of exercise, in combination with other behavioral changes, to induce partial, or full, remission of type 2 diabetes.

How does regularly exercising help in preventing or delaying type 2 diabetes?

The benefit of exercise in preventing diabetes has been demonstrated in several studies. A meta-analysis of 10 studies of physical activity and type 2 diabetes reported a lower risk of developing diabetes with regular moderate physical activity, including brisk walking, compared with being sedentary

Additionally, in a subsequent prospective cohort study in men, either weight training or aerobic exercise for at least 150 minutes per week was associated with a lower risk of developing type 2 diabetes compared to those with  a control group who did no physical activity.

Why is engaging in physical activity important in managing type 2 diabetes?

In patients with type 2 diabetes, studies show that short-term exercise training improves insulin sensitivity just as it does in non-diabetics. In patients with type 2 diabetes treated with medication, exercise tends to lower blood glucose concentrations.

Exercise improves glycemic control in patients with type 2 diabetes, as illustrated by the findings of several meta-analyses of trials examining the effect of exercise on glycemic control in patients with type 2 diabetes. Exercise training reduces glycosylated hemoglobin (A1C) values by approximately 0.5 to 0.7 percentage points compared with control participants.

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Ask Stanford Med, Neuroscience, Surgery

A Stanford neurosurgeon discusses advances in treating brain tumors

A Stanford neurosurgeon discusses advances in treating brain tumors

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Last year, an estimated 70,000 people were diagnosed with a primary brain tumor, which originates and remains in the brain, and far more will develop metastatic brain tumors, those that begin as cancer elsewhere in the body and spread to the brain. Although physicians face a number of challenges in treating these tumors, the encouraging news is that advances in technology and new therapies are improving patient outcomes.

During a Stanford Health Library event on Thursday, Steven Chang, MD, director of the Stanford Neurogenetics Program and the Stanford Neuromolecular Innovation Program, will deliver an update on the latest in surgical and non-surgical treatments of brain tumors. (The lecture will also be webcasted for those unable to attend.) In anticipation of the talk, Chang answered some questions related to the topics he’ll be addressing.

Why has a greater understanding of genetics and the biology of tumors improved physicians’ understanding of how patients will respond to certain therapies?

Having a greater understanding of the genetics and biology of brain tumors helps neurosurgeons to tailor treatments for each patient. In essence, we are able to deliver personalized medicine if we understand which subsets of brain tumors respond to specific treatments. For example, we now understand that gliomas with certain genetic makers are more likely to respond to chemotherapy treatments. The presence or absence of these genetic markers will also help guide patients in determining which clinical trials it may be most appropriate for them to enroll in.

How have advances in brain-mapping technologies made a difference in treating low-grade gliomas, which are slow growing and often affect younger patients?

Low-grade gliomas don’t typically contrast enhance on brain MRI scans. Furthermore, low-grade gliomas are more likely than higher-grade gliomas to have appearances similar to normal brain tissue, with no obvious color or consistency distinction between tumor and normal brain. These factors make resection of low-grade gliomas potentially more complex than high-grade gliomas, which often have distinct appearances from normal brain tissue. Advances in brain-mapping technologies include both image guided navigation and electrophysiologic mapping. Image-guided navigation consists of the use of MR imaging to provide real-time guidance during tumor resections. High-speed computer workstations provide images that show neurosurgeons exactly where they are with respect to brain anatomy during tumor resections. Electrophysiologic mapping is the use of specific electrical simulations of the brain tissue to identify eloquent brain cortex. By mapping out these critical brain regions, the neurosurgeon can safely avoid them when performing tumor resection.

In what ways have improvements in imaging technology over the last decade changed the treatment approach for both surgical and non-surgical treatment of brain tumors?

Improvements in imaging technology over the last several years have provided valuable tools for neurosurgeons in the treatment of brain tumors. A significant advance in surgical treatment of brain tumors has been the development of intraoperative MRI scanners. This allows a surgeon to perform a tumor resection, and then, post resection, perform a set of MR imaging directly in the operating room. If this MR imaging shows residual tumor, the surgeon has an opportunity to perform a further resection prior to completing the surgical operation. Additional imaging advances include functional MR imaging. This provides a graphic representation of critical functions such as speech or motor function. This is useful in determining both whether a patient is inoperative candidate and in assessing risk of the surgical resection.

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Ask Stanford Med, Health and Fitness

Director of Stanford Runner's Injury Clinic discusses treating and preventing common injuries

Director of Stanford Runner's Injury Clinic discusses treating and preventing common injuries

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It may surprise you to learn that past studies show that runners have a 50 percent chance of sustaining an injury that disrupts their training, and those that compete in marathons have an incidence rate as high as 90 percent. But don’t hang up your sneakers just yet. Many common aches and pains that nag runners can easily be treated or avoided.

On Thursday, Michael Fredericson, MD, who is director of the Stanford Runner’s Injury Clinic and has been head team physician with the Stanford Sports Medicine Program since 1992, will talk about the latest running prevention and treatment methods during a Stanford Health Library lecture. (For those unable to attend the event in person, you can watch the live webcast starting at 7 PM Pacifiic time.) To kick off the conversation, I reached out to Fredericson to discuss some of the topics of his upcoming talk, including the harms of overstriding, the benefits of cross-training, and remedies for prevalent joint problems. He and Adam Tenforde, MD, a sports medicine fellow at Stanford, responded to my questions.

How can overstriding lead to injury?

The term “overstriding” refers to running with the foot striking the ground too far forward from normal stride length. This results in heel strike pattern that may increase stress in the hip and knee joints. Research has shown that forefoot strike patterns tend to reduce stress on the knees and hips, although this may lead to greater stress on the foot and ankle. We conduct a clinic called RunSafe, where we evaluate gait of runners using video and markers. More efficient stride frequency is 90 strides per leg per minute. When a runner overstrides, this may result in a lower stride rate and an inefficient gait. We evaluate for the causes of overstriding, including poor hip extensor strength (weak gluteal muscles), decreased flexibility and technique and encourage correction of these biomechanical contributors. Also, we may suggest shoes with reduced weight, such as ‘minimalist shoes’ as these tend to encourage a runner to run with a more mid-foot strike pattern. However, we caution any changes in shoe type or technique be introduced gradually to decrease risk of developing an injury from changes in gait pattern that stress the body in a new way.

Why is it important for runners to cross-train?

Cross-training refers to forms of aerobic exercise that do not involve running. Doing exercises that do not involve the repetitive ground-impact experienced during running help to rest tired muscles and decrease stress on bones, assisting in recovery while building aerobic capacity. There are no established forms of cross-training to prevent injuries, but performing exercises that do not involve impact loading through the legs, such as elliptical trainer, cycling or deep water running may be helpful.

Many runners select shoes that compensate for how their foot pronates. But recent research shows that pronating too much or too little may not actually increase a runner’s risk of injury. How important is pronation and foot type in preventing injuries?

We evaluate foot type and pronation during our RunSafe clinics. Pronation is a normal motion that helps to distribute forces while landing through the foot and ankle, reducing stresses through the lower extremities. If the foot abruptly stops moving from too much or too little pronation, the other joints and lower limbs may absorb these forces and can become injured. Foot type (having too high an arch or too flat a foot) may also result in higher forces in the legs and joints through associated biomechanics. Foot type and concerns of pronation need to be put into context of prior injury history, as recent research has suggested that foot type and pronation do not necessarily predict future injury risk.

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