From Medscape Medical News

 

By Zosia Chustecka

June 16, 2010 — A consensus statement issued jointly by the American Diabetes Association (ADA) and the American Cancer Society (ACS) notes that there are some links between diabetes and cancer, but points out that there are also many unanswered questions.

The statement was written by a panel of experts assembled by the ADA and ACS and headed by Edward Giovannucci, MD, ScD, from the Harvard School of Public Health in Boston, Massachusetts. It is published online June 16 in Cancer.

“Probably the most important point to re-emphasize is that modifiable risk factors (overweight, obesity, lack of exercise, poor diet, and smoking) contribute to both diabetes and cancer risk, probably in part through similar mechanisms, such as insulin resistance and increased inflammation,” Dr. Giovannucci told Medscape Oncology.

The report notes that diabetes, primarily type 2, is associated with an increased risk for some cancers, including liver, pancreas, endometrium, colorectal, breast, and bladder, but it is also associated with a decreased risk for prostate cancer. For other cancer types there is no association or the evidence is inconclusive, they note.

“The 2 diseases are diagnosed within the same individual more frequently than would be expected by chance, even after adjustment for age,” the experts comment, but this association might not be causal, they point out.

“Both diseases are complex, with multiple subtypes,” they note.

“It remains unclear whether the association between diabetes and cancer is direct (e.g., due to hypoglycemia), whether diabetes is a marker of underlying biological factors that alter cancer risk (e.g., insulin resistance and hyperinsulinemia), or whether the association between cancer and diabetes is indirect and due to common risk factors such as obesity,” the authors write.

Some, but not all, epidemiologic studies have suggested that diabetes significantly increases mortality in patients with cancer, the report notes.

“Whether cancer risk is influenced by the duration of diabetes is a critical and complex issue, and may be complicated further by the multidrug therapy often necessary,” they add.

Dr. Giovannucci told Medscape Oncology that diabetics have a higher mortality from all causes, including cancer. “In general, diabetics require careful scrutiny for treatment,” he said. He also said that the treatment of cancer patients who are also diabetics “may be made more complex because of their diabetes,” because they are more likely to have comorbidities and might already be taking drugs that could lead to interactions.

Action Points

Although the data so far suggest that there are links between diabetes and cancer, “it is too early to draw definite conclusions,” said another of the authors, Michael Pollak, MD, professor of medicine and oncology at McGill University in Montreal, Quebec.

“It is certainly important for diabetics, especially diabetics on insulin, to receive at least routine screening for cancer according to standard recommendations,” Dr. Pollak told Medscape Oncology.

In addition, he emphasized that “people with both diseases should try to maintain an ideal body weight . . . to improve the prognosis of both conditions.”

Cancer Risk for Diabetes Drugs

The issue of diabetic treatments being associated with cancer risk has come up only recently, the experts note.

Thus far, early evidence suggests that metformin is associated with a lower risk for cancer and that exogenous insulin is associated with an increased risk (but whether insulin glargine is associated with more of a risk than other insulins is unclear).

However, these observed associations might be confounded by biologic changes that occur with diabetes, for which the drugs are being prescribed, the expert group points out. In addition, the association appears to exist for some types of cancer but not others.

Dr. Pollak added that the possibility that metformin actually reduces the risk for certain cancers in diabetics is being investigated. “Evidence for this is not strong enough at present to recommend the use of metformin for cancer prevention or cancer treatment,” he said, “although this is an active research area.”

When it comes to choosing between available diabetes therapies for the average patient, the experts state that “cancer risk should not be a major factor” in the choice, although “more careful consideration” might be required for selected patients who have a very high risk for cancer occurrence.

Summarizing the new report in a statement to the press, Dr. Giovannucci said: “Traditionally, there hasn’t been much overlap between research in cancer and diabetes. But recently, it’s become clearer that there are fascinating links between the 2. Our summary may raise more questions than answers, but we hope that it will spur additional studies.”

Dr. Giovannucci has disclosed no relevant financial relationships. Dr. Pollak reports receiving research support from Pfizer and serving as a consultant to Sanofi-Aventis and Novo Nordisk. Many of the coauthors also report relationships with pharmaceutical industries; these are detailed in the paper. The conference at which this consensus statement was developed was supported by unrestricted grants from Amylin, Lilly, Merck & Co, Novo Nordisk, and Sanofi Aventis.

Cancer. Published online June 16, 2010.

Authors and Disclosures

Journalist

Zosia Chustecka

Zosia Chustecka is news editor for Medscape Hematology-Oncology and prior news editor of jointandbone.org, a Web site acquired by WebMD. A veteran medical journalist based in London, UK, she has won a prize from the British Medical Journalists Association and is a pharmacology graduate. She has written for a wide variety of publications aimed at the medical and related health professions. She can be contacted at ZChustecka@webmd.net.

Zosia Chustecka has disclosed no relevant financial relationships.

The New York Times, May/June, 2010, by Gretchen Reynolds  –  Most of us think that exercise improves sleep. But it may be that thinking that exercise improves sleep improves sleep. That, at any rate, is the provocative finding of a new study completed recently in Switzerland and published last month in the journal of the American College of Sports Medicine.

For the study, 862 Swiss college students were asked to record how much they exercised, how fit they believed themselves to be (on a scale from 1 to 10) and how well they slept (on a scale from 1 to 8). The correlations between how much some of the students exercised and how fit they believed themselves to be was not very precise. More than 16 percent of the students who rated themselves low on the fitness scale actually exercised the most. In other words, they worked out more than many of the other students but felt they weren’t doing enough.

Those students who perceived that they weren’t exercising enough also tended to report sleeping less well, even though they were exercising more than some of the other students. In the end, the researchers found almost no correlation between how much students exercised and how well they slept. What mattered was whether they believed that they were being active enough. Those students who perceived that they were fit slept well. Those who didn’t, did not.

As Markus Gerber, a researcher at the Institute of Exercise and Health Sciences at the University of Basel and lead author of the study told me in an e-mail message that the findings suggest that, when it comes to the role of exercise and sleep, “what people think is more important than what they do.”

That conclusion is not, in fact, anomalous. It actually fits neatly into a large if little-known body of science intimating that exercise may not ease you to sleep after all. The relationship between exercise and sleep “is certainly complicated,” said Shawn Youngstedt, an associate professor of exercise science at the University of South Carolina and author of some of the science in question.

In a representative study that he led several years ago, for instance, college students — some athletic, some sedentary — kept detailed sleep and exercise diaries for months. At the end of that time, the researchers cross-referenced the diaries and found no notable correlation between exercising more and sleeping better or vice versa. Meanwhile, in a second part of the same study, a group of adults wore monitors that recorded their movements and sleep patterns. The participants also filled out activity diaries. Using the objective data from the monitors, together with the diary reports, the researchers found only marginal impacts on sleep from exercise. The most active volunteers tended to fall asleep about a minute and a half faster than those who were the least active. Otherwise, their sleep was virtually identical.

But most of us continue to believe that working out is helpful to snoozing, as shown in a number of large-scale, international surveys completed in the past decade, during which respondents have consistently reported that they slept better on days when they exercised. Parse the results closely, though, and the link grows more tenuous. Respondents often report, for instance, that they sleep well on the weekends, when they have enough time to exercise, but also when they’re free of bosses, deadlines, rushed lunch breaks and other stressors that can disrupt sleep. Similarly, as Mr. Youngstedt points out, the surveys rarely are able to take into account such confounding issues as smoking, weight, anxiety or exposure to sunlight, all of which have been found in studies to affect sleep.

Perhaps the most surprising finding of the current science about exercise and sleep, however, is that wearing yourself out physically is not the same as being sleepy. “The two are easily mistaken,” Mr. Youngstedt said, but they seem to affect various bodily systems at the same time in different ways. Hard, long workouts or severe overtraining may be just as likely, in fact, to lead to wakefulness and sleep problems, Mr. Youngstedt said, than to better sleep. On the other hand, a related truism about exercise and sleep appears to be a myth. There is “absolutely no scientific evidence” that working out in the late evening keeps you from sleeping, Mr. Youngstedt said.

In the end, the current state of the science about sleep and exercise is somewhat cloudy. But more clarity may come, Mr. Youngstedt said. He, for one, is not convinced that there is no link between exercise and sleep. But most laboratory studies to date, including his, have involved volunteers without underlying sleep problems.

“There’s no room for exercise to improve sleep, if people are sleeping fine,” he said.

To sidestep that issue, he and his colleagues have a number of studies under way that use volunteers with sleep pathologies, like sleep apnea, to discern whether exercise helps in those cases. Results, so far, Mr. Youngstedt said, “are promising.”

Still, the most practical advice that science can offer at the moment about exercise and sleep is not to fret too much about whether you’re getting enough of either. Worrying, as the Swiss study showed, is what will keep you awake long into the night.

“I would give the following recommendation,” Mr. Gerber, the Swiss scientist, wrote. “It does not matter how much exercise” you actually complete “as long as it make you feel good and feel fit.”

Massively enlarged tonsils can cause episodes of cessation of breathing known as obstructive sleep apnea. Cessation of breathing can last 10 seconds or longer, causing extremely low levels of oxygen in the blood.
 

THE FACTS

The New York Times, May/June, 2010, by Anahad O’Connor  –  For people suffering from sleep apnea, specialized breathing machines are the standard treatment.

The machines use a method called continuous positive airway pressure, or CPAP, which keeps the airway open and relieves potentially dangerous pauses in breathing during the night. But the machines are expensive, and some people complain that the mask and headgear cause uncomfortable side effects, like congestion.

One free and fairly simple alternative may be exercises that strengthen the throat. While they aren’t as established or as well studied as breathing machines, some research suggests they may reduce the severity of sleep apnea by building up muscles around the airway, making them less likely to collapse at night.

In a study published last year in The American Journal of Respiratory and Critical Care Medicine, scientists recruited a group of people with obstructive sleep apnea and split them into two groups. One was trained to do breathing exercises daily, while the other did 30 minutes of throat exercises, including swallowing and chewing motions, placing the tip of the tongue against the front of the palate and sliding it back, and pronouncing certain vowels quickly and continuously.

After three months, subjects who did the throat exercises snored less, slept better and reduced the severity of their condition by 39 percent. They also showed reductions in neck circumference, a known risk factor for apnea. The control group showed almost no improvement.

Other randomized studies have found similar effects. One even showed that playing instruments that strengthen the airways, like the didgeridoo, can ease sleep apnea.

THE BOTTOM LINE

For people with sleep apnea, throat exercises may be a cheap and useful therapy.

ANAHAD O’CONNOR scitimes@nytimes.com

 

NIH.gov

Guimarães KC, Drager LF, Genta PR, Marcondes BF, Lorenzi-Filho G.

Sleep Laboratory, Pulmonary Division, Heart Institute (InCor), University of São Paulo Medical School, Av Dr Enéas Carvalho de Aguiar, 44, CEP 05403-904, São Paulo, Brazil.

Comment in:

       Am J Respir Crit Care Med. 2009 May 15;179(10):858-9.

Abstract

RATIONALE: Upper airway muscle function plays a major role in maintenance of the upper airway patency and contributes to the genesis of obstructive sleep apnea syndrome (OSAS). Preliminary results suggested that oropharyngeal exercises derived from speech therapy may be an effective treatment option for patients with moderate OSAS. OBJECTIVES: To determine the impact of oropharyngeal exercises in patients with moderate OSAS. METHODS: Thirty-one patients with moderate OSAS were randomized to 3 months of daily ( approximately 30 min) sham therapy (n = 15, control) or a set of oropharyngeal exercises (n = 16), consisting of exercises involving the tongue, soft palate, and lateral pharyngeal wall. MEASUREMENTS AND MAIN RESULTS: Anthropometric measurements, snoring frequency (range 0-4), intensity (1-3), Epworth daytime sleepiness (0-24) and Pittsburgh sleep quality (0-21) questionnaires, and full polysomnography were performed at baseline and at study conclusion. Body mass index and abdominal circumference of the entire group were 30.3 +/- 3.4 kg/m(2) and 101.4 +/- 9.0 cm, respectively, and did not change significantly over the study period. No significant change occurred in the control group in all variables. In contrast, patients randomized to oropharyngeal exercises had a significant decrease (P < 0.05) in neck circumference (39.6 +/- 3.6 vs. 38.5 +/- 4.0 cm), snoring frequency (4 [4-4] vs. 3 [1.5-3.5]), snoring intensity (3 [3-4] vs. 1 [1-2]), daytime sleepiness (14 +/- 5 vs. 8 +/- 6), sleep quality score (10.2 +/- 3.7 vs. 6.9 +/- 2.5), and OSAS severity (apnea-hypopnea index, 22.4 +/- 4.8 vs. 13.7 +/- 8.5 events/h). Changes in neck circumference correlated inversely with changes in apnea-hypopnea index (r = 0.59; P < 0.001). CONCLUSIONS: Oropharyngeal exercises significantly reduce OSAS severity and symptoms and represent a promising treatment for moderate OSAS. Clinical trial registered with www.clinicaltrials.gov (NCT 00660777).

PMID: 19234106 [PubMed – indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/19234106

Aaron Houston for The New York Times

Dan Hajjar testing a breathing device at a sleep clinic in Morristown, N.J. Though awkward, the device, called C.P.A.P., still is the most effective treatment for sleep apnea.

By BENEDICT CAREY

In Brief:

Sleep helps to consolidate long-term memories and rejuvenate damaged tissues.

These functions are performed during different stages of sleep, recent brain imaging studies suggest.

There may be many forms of sleep deprivation: some patients may be missing the shallow state called rapid eye movement, while others may be deficient in slow-wave sleep.

To induce sleep with all of its benefits, scientists must develop drugs that emulate each of its stages.

Why do we sleep?

It’s a fundamental fact of animal and human life, but researchers still do not know for sure why sleep is necessary. Theories abound: Perhaps the body repairs damaged, worn tissues when asleep. Maybe it recharges itself, as if it were a biological battery. Or perhaps sleep affords the brain the opportunity to integrate important facts, memories and emotional impressions recorded from the previous day.

The answer is probably all of the above, but the researchers increasingly are focused on the role sleep plays in stabilizing and consolidating memories. Recent studies appear to catch the process of memory integration in action, and they hint at a neural nightlife that is richer than previously known. The sleeping brain not only sorts important facts from trivia, the findings suggest, but it also replays social interactions and carefully shades experiences with emotional color so they will be more comprehensible.

That’s why interruptions to normal sleep can be so insidious. More than 50 million Americans suffer some sleep problem, from mundane nagging insomnia to more exotic disorders, like bruxism, the official name for teeth grinding, restless leg syndrome or narcolepsy. Of these, a disorder called obstructive sleep apnea causes perhaps the most misery: during the night, the upper airway narrows so much that the body jerks awake, continually gasping for breath.

Each interruption of sleep breaks the spell of “nature’s soft nurse,” in Shakespeare’s phrase. No one who has slept poorly for a week or more is surprised to hear that sleeping problems are linked to physical problems, like high blood pressure, and emotional trouble, especially depression. And those who go long enough without sleep are at risk of a psychotic break, complete with hallucinations.

As neurologists now see it, each awakening throws light into the brain’s darkroom just as an intricate mental photo is being developed. Some of the latest research tries to link stages of sleep to specific functions, like stabilizing memory, so that doctors can better treat sleep-related problems.

Sleep comes in several forms, including deep, or slow-wave, sleep and the shallow, dream-rich state called rapid eye movement, or R.E.M. It is during slow-wave sleep that the body circulates high levels of hormones thought to be involved in tissue repair. And it is during the same stage that the brain seems to reinforce intellectual memories most effectively, like memorized words and numbers.

Recently scientists have gained unprecedented glimpses into the workings of the brain during slow-wave sleep. In one study, German researchers demonstrated that the whiff of a familiar scent helped sleeping students better remember things they had learned the night before. The smell of roses — delivered to people’s nostrils as they studied and, later, as they slept — seemed to intensify the process of normal memory consolidation. When the student were exposed to the fragrance while in slow-wave sleep, an area of their brains called the hippocampus flared with activity, apparently working to make sense of the previous day’s events.

Bursts of the fragrance delivered during R.E.M. sleep had no effect, the researchers found. This makes some sense; the students had studied the location of card pairs, a strictly intellectual task devoid of the narrative or emotional content that so often fills R.E.M.

The dreamy riot of images during R.E.M., some scientists argue, may reflect the brain’s efforts to integrate emotional reactions, in effect attaching mood lighting to a scene whose details might be consolidated in other brain areas.

Researchers in Massachusetts recently analyzed the dream journals of students, comparing entries before and after Sept. 11, 2001. The students’ dreams changed markedly after the attacks, containing four times as many threatening images, many clearly echoing the catastrophe.

“When things are emotional, and context and meaning become important, and you’re thinking about how all these pieces fit together — that seems to migrate to R.E.M.,” said Dr. Robert Stickgold, a psychiatrist at Harvard University.

And a 2005 study, which analyzed dream journals as well as readings from eyelid movement sensors, found that aggressive social interactions were more likely to be processed during R.E.M. than during non-R.E.M. sleep.

Scientists are coming to believe that each stage of sleep is specialized for the brain’s deconstruction and processing of a particular kind of information, and so the fine distinctions between R.E.M. sleep, slow-wave sleep and other stages are increasingly important. While sleep medications now on the market effectively induce sleep, they do not usually increase the slow-wave variety. Pill-induced slumber is far better than insomnia, but it may not truly substitute for naturally deep sleep and the concentrated memory consolidation that it brings.

Individuals vary widely in the amount and quality of sleep they get, and as we age, our bodies seem less able to plumb sleep’s rich depths. Some of us probably are in desperate need of slow-wave sleep; others are likely to be starved for R.E.M.

In the coming years the challenge for sleep research, and its promise, is to give doctors and red-eyed patients opportunities not only to sleep more, but to reshape the quality of the sleep they get.

Karen Tam for The New York Times

Dr. Lee Surkin, with his wife, Elizabeth Webster, uses a Watermark Medical device to record patients’ sleep patterns, which specialists interpret and summarize for him.

The New York Times, May/June, 2010, by Steve Lohr  –  MENTION health care reform and the image that instantly comes to mind is a big government program. But there is another broad transformation in health care under way, a powerful force for decentralized innovation. It is fueled in good part by technology — low-cost computing devices, digital sensors and the Web.

The trend promises to shift a lot of the diagnosis, monitoring and treatment of disease from hospitals and specialized clinics, where treatment is expensive, to primary care physicians and patients themselves — at far less cost.

The new models emphasize early detection of health problems, prevention and management of chronic disease. The approaches have adopted a range of labels including “wellness,” “consumer-directed health care” and the “medical home.”

The potential transformation faces formidable obstacles, to be sure. Some of those hurdles include getting patients to embrace healthier lifestyles and persuading the government and insurers to reimburse at-home testing and monitoring devices.

Yet the promise, according to Dr. David M. Lawrence, the former chief executive of Kaiser Permanente, the nation’s largest private health care provider, is “an array of technology-enabled, consumer-based services that constitute a new form of primary health care.”

To glimpse the business opportunity — and the challenge — at the forefront of this emerging, decentralized health care market, let’s look at a start-up in the field of sleep medicine.

The start-up, Watermark Medical, offers an at-home device and a Web-based service for diagnosing sleep apnea. Characterized by snoring and pauses in breathing, sleep apnea is a serious health problem that often goes undiagnosed.

Typically caused by tissue in the back of the throat obstructing the airway to the lungs, it contributes to the severity of chronic conditions including diabetes, heart disease, obesity, hypertension and depression, adding an estimated $3.4 billion to the nation’s health costs.

Sufferers battle chronic fatigue, and sleep experts suspect that apnea is the cause of many workplace and car accidents. Treatments include a masklike apparatus that pumps air to keep the patient’s airway open; an oral appliance, resembling an orthodontic retainer, that helps open the throat; and surgery to shave tissue that blocks the air passage.

Today, sleep apnea diagnoses are mainly done in specialized sleep clinics, where the patient sleeps under observation for a night or two, at a cost of up $4,000 — with the expense usually shared by insurers and patients. Given the cost and inconvenience, physicians say, patients often do not go to a clinic and seek treatment until their sleep troubles are severe.

Watermark Medical traces its technical origins to the work of Dr. Philip Westbrook, a Stanford-educated sleep expert who led the sleep disorder centers at the Mayo Clinic in Rochester, Minn., and at Cedars-Sinai Medical Center in Los Angeles. But during a brief period in private practice in California, seeing the expense and trouble sleep-testing was for patients, Dr. Westbrook decided there had to be a simpler, more efficient way.

He teamed up with a pair of medical-device technologists and won an innovation grant from the National Institutes of Health to finance a prototype. They came up with a headband that holds a blue plastic device — smaller than a deck of cards and resting on the forehead — equipped with a microprocessor and sensors, and a tube that fits into a patient’s nose. If the tube falls out, the patient hears a voice prompt.

In 2004, the device was approved for use by the Food and Drug Administration. “We had a better mousetrap, but no business or marketing expertise,” Dr. Westbrook said.

But there also wasn’t a real market, until the Centers for Medicare and Medicaid Services approved reimbursement for home sleep-testing in 2008. That was when two young entrepreneurs, Sean Heyniger and Charles Alvarez, who had recently sold PDSHeart, a remote heart-monitoring company, to a larger corporation, were looking for another opportunity. They researched the sleep market and found Dr. Westbrook, who is now Watermark’s chief medical officer.

They founded Watermark in March 2008, tweaked Dr. Westbrook’s device, produced a business model and conducted pilot projects. Watermark began introducing its testing device last September. Its sensor-equipped headband, powered by Intel’s Atom microprocessor, measures 10 things, including blood-oxygen saturation, air flow, pulse rate and snoring levels.

The patient wears the device for a night or two, then returns the device to the doctor’s office. The data is downloaded to a personal computer, then sent on the Web to a network of sleep professionals, one of whom delivers a report to the physician within 48 hours, with a diagnosis and suggested treatment. The physicians typically charge from $250 to $450 a test, and a doctor collects $100 to $150 of that. “It’s a new revenue stream for the physician,” said Mr. Alvarez, Watermark’s president.

Watermark also charges the physicians $4,000 for each digital headband.

So far, 35,000 patients have been tested using the Watermark device, with more than 1,000 doctors prescribing about 4,000 tests a month.

DR. LEE SURKIN, a sole practitioner in Greenville, N.C., is one of them. He has three Waterman devices and has done at-home tests on 50 patients so far.

Owning his own sleep lab, Dr. Surkin said, would be far more lucrative under current insurer reimbursement rates, but he prefers the at-home tests as a low-cost way to diagnose and treat far more patients. “This is a tool that moves health care toward where it has to go,” he said.

If successful with sleep, Watermark plans to branch out to other kinds of Web-based personal devices to monitor chronic conditions like heart disease and diabetes. The company’s executives talk of their technology as a platform that can add many other services someday, a bit like Apple’s applications store for its consumer devices.

Indeed, Watermark’s co-chairman and a major financial backer is John Sculley, the former chief executive of Apple. “We’re starting with sleep, but the model can extend to many other diagnostic services,” he said.