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No one likes to walk into work after just a few fitful hours of sleep. But now there's evidence that not getting enough sleep may have more serious consequences than dark circles under your eyes the next morning. Researchers at the University of Chicago report in the Journal of the American Medical Association that too little sleep can promote calcium buildup in the heart arteries, leading to the plaques that can then break apart and cause heart attacks and strokes.

The University of Chicago team documented for the first time exactly how much of a risk shortened shut-eye can be — one hour less on average each night can increase coronary calcium by 16%. Among a group of 495 men and women aged 35 to 47, 27% of those getting less than five hours of sleep each night showed plaque in their heart vessels, while 11% of those sleeping the recommended five to seven hours did, and only 6% of subjects sleeping more than seven hours each night showed such atherosclerosis. "We were surprised by the findings," says Diane Lauderdale, a professor of health studies at the University of Chicago and lead author of the study. "We really were not expecting to find an association at all, and certainly not one that was this strong." (See the Top 10 Medical Breakthroughs of 2008.)

Lauderdale and her team had reason to be skeptical. While the connection between sleep and heart disease is of growing interest to researchers, earlier studies had been inconclusive, and plagued by biases, including the fact that most of the trials relied on people's self-reported accounts of their sleeping habits. The scientists knew that teasing apart the myriad processes that contribute to sleep, and then drawing scientifically sound connections between them and the host of things that can trigger heart disease, would be difficult at best. So the Chicago team isolated the most common confounding variables that could explain both poor sleep and heart problems, such as smoking, alcohol, and other medical conditions, and also found a way to record, as accurately as possible, the amount of sleep that the subjects got each night. Each volunteer wore a wrist monitor that measured and recorded activity at 30 second intervals; when the monitor was quiet, the subject was asleep.

While Lauderdale acknowledges that her results are far from the last word on sleep and heart disease, the study does suggest that doctors and patients should consider sleep in addition to the more familiar hazards for the heart such as high cholesterol, hypertension and diabetes. In Lauderdale's analysis, one additional hour of sleep was equivalent to lowering systolic blood pressure by 16.5mm Hg. "We have enough evidence from this study and others to show that it is important to include sleep in any discussion of heart disease," says Dr. Tracy Stevens, spokesperson for the American Heart Association and a cardiologist at Saint Luke's Mid-America Heart Institute. "We talk about the traditional risk factors, and now the other important thing we need to include is sleep." (See pictures of how animals sleep.)

Exactly how a lack of sleep is feeding plaque in the heart arteries isn't yet clear, but one explanation may involve inflammation. Too little sleep can raise cortisol levels, which fuels inflammation that can destabilize plaques. Once these deposits rupture, they can block vessels in the heart or brain, causing a heart attack or stroke. While the Chicago team did not track levels of cortisol to test this theory, future studies might.

A simpler explanation might involve blood pressure. In general, blood pressure dips during sleep, and over a 24 hour period, people sleeping less will have shorter periods of lower blood pressure, thus increasing their tendency to dislodge any unstable plaques.

Whatever the reason might be, the results of this study make it clear that sleep isn't just for dreamers. Getting enough sleep might just save your heart.

Read more: http://www.time.com/...l#ixzz2NeMOooxh

New research published in the American Journal of Clinical Nutrition (AJCN) suggests drinking sodas and other sugary beverages may significantly increase stroke risk, particularly among women. The study out of Japan found that, compared to women who drink virtually no sugary beverages, women who drink about one a day are 83 percent more likely to suffer an ischemic stroke, the most common form of stroke, and the type that involves a blood clot blocking blood flow to the brain.

Dr. Hiroyasu Iso from Osaka University and his colleagues evaluated data collected on 40,000 people who filled out questionnaires at three time intervals, once in 1990, and again in 1995 and 2000. These individuals shared details about their dietary and lifestyle habits, including how many sodas or sugar-sweetened juices and other beverages they consumed daily. Excluded from consideration were so-called "diet" sodas and 100 percent fruit juices.

Upon analysis, the team observed that ischemic stroke risk increased progressively depending on how many sugary beverages participants consumed in a given week. At lowest risk were women who drank virtually no soft drinks or sugary beverages at all -- out of 11,800 in this group, only 205, or 1.7 percent, had an ischemic stroke in the followup years. At the same time, 28 women out of 921 who drank at least one sugary beverage per day went on to have a stroke, representing a three percent stroke rate for this group.

"It makes sense, if (sugar sweetened beverages) increase the risk for obesity, diabetes, insulin resistance, inflammation, then it should, in fact, raise the risk for cardiovascular disease, and that's what we're seeing," said Dr. Adam Bernstein from the Cleveland Clinic, who was not directly involved with the research, about the study. "No single strategy is going to solve the problem, and I think a multi-pronged approach is going to work."

by Jonathan Benson

New research about brain stimulation, the passing of electrical currents through the brain, was discussed at a major science conference in Chicago this week. The new therapy may lead to improved recoveries from stokes.

A conference held in April in Chicago of cognitive neuroscientists discussed a technique of brain stimulation, or , to give it the full scientific name - transcranial direct current stimulation (tDCS). The research team behind a series of trials were based at University College London, UK.

tDCS is a form of neurostimulation which uses constant, low current delivered directly to the brain area of interest via small electrodes. The technique works by sending constant, low direct current through electrodes. When these electrodes are placed close to the region of the brain of concern, the current induces electrical flow. The flow can then either increase or decrease the the way that brain neurones react which leads to alteration of brain function.

What the research team behind some recent studies put forwards was the tDCS ) can have various positive effects on the brain lasting for up to 12 months, Science News reported. In particular, non-invasive brain stimulation had a positive effect in aiding recovery among stroke sufferers.

One aspect of the new research demonstrated that tDCS treatment can aid the recovery of language skills. The positive benefits highlighted by the UK team also related to a different set of experiments from the Mackenzie Presbyterian University in Sao Paolo, which showed brain stimulation can trigger better memory retention.
To add to this, further research from the University of Oxford showed that the technique can aid people with numeracy problems. In relation to this, Roi Cohen Kadosh, the lead researcher said in a press release "These experiments advance our understanding of how numerical abilities are subserved in the typical and atypical brain, and provide a possible means to improve numerical cognition, thus having important implications for education, intervention, and rehabilitation."
The sum total of the research suggests several wide-ranging applications. One key benefit of the therapy is that it is painless, relatively inexpensive and is apparently safe.

Although such therapies are evidently in their 'early days', the methods do have potential and are worth keeping track of.

By Tim Sandle
Apr 12, 2012