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Tuesday, May 31, 2016

A Personalized Virtual Heart Predicts the Risk of Sudden Cardiac Death

New Technology Finds Patients Who Are Most Likely to Face Lethal Arrhythmias

Newswise, May 31, 2016 — When electrical waves in the heart run amok in a condition called arrhythmia, sudden death can occur. 

To save the life of a patient at risk, doctors currently implant a small defibrillator to sense the onset of arrhythmia and jolt the heart back to a normal rhythm.

But a thorny question remains: How should doctors decide which patients truly need an invasive, costly electrical implant that is not without health risks of its own?

To address this, an interdisciplinary Johns Hopkins University team has developed a non-invasive 3-D virtual heart assessment tool to help doctors determine whether a particular patient faces the highest risk of a life-threatening arrhythmia and would benefit most from a defibrillator implant. 

In a proof-of-concept study published May 10 in the online journal Nature Communications, the team reported that its new digital approach yielded more accurate predictions than the imprecise blood pumping measurement now used by most physicians.

“Our virtual heart test significantly outperformed several existing clinical metrics in predicting future arrhythmic events,” saidNatalia Trayanova, the university’s inaugural Murray B. Sachs Professor of Biomedical Engineering. “This non-invasive and personalized virtual heart-risk assessment could help prevent sudden cardiac deaths and allow patients who are not at risk to avoid unnecessary defibrillator implantations.”
Trayanova, a pioneer in developing personalized imaging-based computer models of the heart, supervised the research and was senior author of the journal article. She holds faculty appointments within Johns Hopkins’ Whiting School of Engineering and its School of Medicine, and she is a core faculty member of the university’s Institute for Computational Medicine. 

For this study, she joined forces with cardiologist and co-author Katherine C. Wu, associate professor in the Johns Hopkins School of Medicine, whose research has focused on magnetic resonance imaging approaches to improving cardiovascular risk prediction.

For this landmark study, Trayanova’s team formed its predictions by using the distinctive magnetic resonance imaging (MRI) records of patients who had survived a heart attack but were left with damaged cardiac tissue that predisposes the heart to deadly arrhythmias. 

The research was a blinded study, meaning that the team members did not know until afterward how closely their forecasts matched what happened to the patients in real life. This study involved data from 41 patients who had survived a heart attack and had an ejection fraction—a measure of how much blood is being pumped out of the heart—of less than 35 percent.

To protect against future arrhythmias, physicians typically recommend implantable defibrillators for all patients in this range, and all 41 patients in the study received the implants because of their ejection fraction scores. But research has concluded that this score is a flawed measure for predicting which patients face a high risk of sudden cardiac death.

The Johns Hopkins team invented an alternative to these scores by using pre-implant MRI scans of the recipients’ hearts to build patient-specific digital replicas of the organs. 

Using computer-modeling techniques developed in Trayanova’s lab, the geometrical replica of each patient’s heart was brought to life by incorporating representations of the electrical processes in the cardiac cells and the communication among cells.

 In some cases, the virtual heart developed an arrhythmia, and in others it did not. The result, a non-invasive way to gauge the risk of sudden cardiac death due to arrhythmia, was dubbed VARP, short for virtual-heart arrhythmia risk predictor. 

The method allowed the researchers to factor in the geometry of the patient’s heart, the way electrical waves move through it and the impact of scar tissue left by the earlier heart attack.

Eventually, the VARP results were compared to the defibrillator recipients’ post-implantation records to determine how well the technology predicted which patients would experience the life-threatening arrhythmias that were detected and halted by their implanted devices. 

Patients who tested positive for arrhythmia risk by VARP were four times more likely to develop arrhythmia than those who tested negative. Furthermore, VARP predicted arrhythmia occurrence in patients four-to-five times better than the ejection fraction and other existing clinical risk predictors, both non-invasive and invasive.

“We demonstrated that VARP is better than any other arrhythmia prediction method that is out there,” Trayanova said. “By accurately predicting which patients are at risk of sudden cardiac death, the VARP approach will provide the doctors with a tool to identify those patients who truly need the costly implantable device, and those for whom the device would not provide any life-saving benefits.”
Wu agreed that these encouraging early results indicate that the more nuanced VARP technique could be a useful alternative to the one-size-fits-all ejection fraction score.

“This is a ground-breaking proof-of-concept study for several reasons,” Wu said, “As cardiologists, we obtain copious amounts of data about patients, particularly high-tech imaging data, but ultimately we use little of that information for individualized care. 

"With the technique used in this study, we were able to create a personalized, highly detailed virtual 3-D heart, based on the patient's specific anatomy. Then, we were able to test the heart virtually to see how irritable it is under certain situations. 

"We could do all this without requiring the patient to undergo an invasive procedure. This represents a safer, more comprehensive and individualized approach to sudden cardiac death risk assessment.”

Wu pointed out that an implantable defibrillator also has a few risks of its own and that avoiding implantation of this device when it is not truly needed eliminates these risks. 

Implantable defibrillators, she said, require invasive access to the heart, frequent device checks and intermittent battery changes. Complications, she added, can include infection, device malfunction and, in rare instances, heart or blood vessel damage.

In addition to eliminating unnecessary device implantations, Trayanova noted that this new risk prediction methodology could also be applied to patients who had prior heart damage, but whose ejection fraction score did not target them for therapy under current clinical recommendations. Thus, Trayanova said, VARP has the potential to save the lives of a much larger number of at-risk patients.
With the proof-of-concept study completed, the researchers next hope to conduct further tests involving larger groups of heart patients. The VARP technique is covered by patent protection obtained through the Johns Hopkins Technology Ventures office.
The first author of the Nature Communications article was Hermenegild J. Arevalo, who conducted the VARP simulations for the cohort of 41 patients. Arevalo earned his doctorate in Trayanova’s lab, then served as a postdoctoral fellow, supervising the undergraduates who contributed to the virtual heart research. 

For his work on this project Arevalo won the 2016 Young Investigator Award at the Heart Rhythm Scientific Sessions. 

The co-lead author was Fijoy Vadakkumpadan, who also worked as a postdoctoral fellow in Trayanova’s lab. Along with Trayanova and Wu, the co-authors were Eliseo Guallar, a professor of epidemiology in Johns Hopkins’ Bloomberg School of Public Health; and Alexander Jebb and Peter Malamas, both Whiting School of Engineering undergraduates majoring in biomedical engineering.

Funding for the research was provided by Trayanova’s NIH Pioneer Award DP1-HL123271; American Heart Association grant 13SDG145100061; W.W. Smith Charitable Trust Heart Research grant H1202; and Wu’s NIH Grant HL103812.

Wednesday, May 25, 2016

Chronic Fatigue Patients More Likely to Suppress Emotions

'Fight or flight' biological response may contribute to fatigue

Chronic Fatigue Patients Likely t Suppress EmotionsNewswise, May 25, 2016-- Chronic fatigue syndrome patients report they are more anxious and distressed than people who don’t have the condition, and they are also more likely to suppress those emotions.

In addition, when under stress, they show greater activation of the biological ”fight or flight” mechanism, which may add to their fatigue, according to new research published by the American Psychological Association.

“We hope that this research will contribute to a greater understanding of the needs of people with chronic fatigue syndrome, some of whom may tend not to communicate their experiences of symptoms or stress to other people,” said the study’s lead author, Katharine Rimes, PhD, of King’s College London.

“Others may be unaware of the difficulties experienced by chronic fatigue syndrome patients and therefore not provide appropriate support.”

Participants who felt that expressing their emotions was socially unacceptable were more likely to suppress them. This was the case for both chronic fatigue patients and healthy people, according to the study published in the APA journal Health Psychology.

This study of 160 people in the U.K. relied on self and observer reports, as well as physiological responses that were collected before, during or after the participants watched a distressing film clip. Half of the participants had been diagnosed with chronic fatigue syndrome while the rest were healthy.

Half of each group were instructed to suppress their emotions and half were told to express their feelings as they wished.

Their reactions were filmed and rated by independent observers. Skin conductance was measured because this increases with greater sweating, which is a sign of activation of the body’s sympathetic nervous system. This is often known as the biological fight or flight system used to cope with stress.

Regardless of the instruction they received, the chronic fatigue syndrome participants reported higher anxiety and sadness, and their skin responses indicated they were more distressed than the healthy control group, both before and after the film.

However, those emotions in the chronic fatigue group were less likely to be picked up by the independent observers.

Greater activation of the fight or flight system was associated with greater increases in fatigue in the people with chronic fatigue syndrome, but not among healthy people.

 “Patients with chronic fatigue syndrome often tell us that stress worsens their symptoms, but this study demonstrates a possible biological mechanism underlying this effect,” said Rimes.

The authors note that this study was conducted with mainly white patients who were attending a special clinic for chronic fatigue syndrome patients and that more research is needed to determine whether elevated emotional suppression would also be found in chronic fatigue patients in more diverse populations.

Since this study was conducted among people who had already been diagnosed with chronic fatigue syndrome, this does not indicate a causal link between emotional suppression and the syndrome itself, Rimes added.

“These findings may help us understand why some chronic fatigue syndrome patients don’t seek out social support at times of stress,” said Rimes. 

Wednesday, May 18, 2016

Research Indicates That Many Are Using Sunscreen Incorrectly

Use Sunscreen Correctly
Dermatologists recommend comprehensive sun protection for skin cancer prevention

Newswise, May 18, 2016— How well do you understand sunscreen? For many consumers, the answer is not so well. According to new research, many people are still puzzled by the wide range of SPF numbers on product labels, and some may not be using sunscreen properly, which could increase their skin cancer risk.

In a 2016 American Academy of Dermatology survey, only 32 percent of respondents knew that an SPF 30 sunscreen does not provide twice as much protection as an SPF 15 sunscreen. Moreover, only 45 percent knew that a higher-SPF sunscreen does not protect you from the sun longer than a lower-SPF sunscreen.

“It’s important that everyone understands what they are seeing on a sunscreen label,” says board-certified dermatologist Abel Torres, MD, JD, FAAD, president of the AAD.

“A sunscreen with an SPF of 30 blocks up to 97 percent of the sun’s rays. Higher SPFs block slightly more rays, but a higher-number SPF does not allow you to spend more time outdoors without reapplication; all sunscreens should be reapplied every two hours, or after swimming or sweating.”

And while 85 percent of participants in the AAD survey knew that sunscreen needs to be reapplied after swimming, a new study from the Johns Hopkins University School of Medicine, published in the Journal of the American Academy of Dermatology on May 16, indicates that some people may not be using sunscreen correctly.

In studying 758 people with a history of nonmelanoma skin cancer and 34,161 control subjects, the authors found that those with a history of NMSC were more likely to seek shade, wear protective clothing and apply sunscreen, but they still received sunburns as often as those without a history of NMSC. While seeking shade and wearing protective clothing were associated with lower odds of sunburn, sunscreen use was not.

“While it makes sense that people with a history of skin cancer were more likely to practice sun protection, we were surprised to see that their methods were not always effective,” says board-certified dermatologist Anna L. Chien, MD, FAAD, one of the study’s co-authors.

“Our results reinforce the importance of everyone using multiple types of sun protection; people who rely only on sunscreen may not be applying enough, covering all their exposed skin or reapplying often enough to shield themselves from the sun’s harmful UV rays.”
The AAD recommends that everyone protect themselves from the sun by seeking shade; wearing protective clothing, such as a long-sleeved shirt, pants, a wide-brimmed hat and sunglasses; and using a broad-spectrum, water-resistant sunscreen with an SPF of 30 or higher, applying enough to cover all exposed skin — for most adults, this is about 1 ounce, or enough to fill a shot glass. Sunscreen should be applied 15 minutes before sun exposure and reapplied every two hours, or after swimming or sweating.

For more information about how to prevent and detect skin cancer, including instructions on how to perform a skin self-exam, There,you can download a body mole map for tracking changes in your skin and find free SPOTme® skin cancer screenings in your area. SPOT Skin Cancer™ is the AAD’s campaign to create a world without skin cancer through public awareness, community outreach programs and services, and advocacy that promote the prevention, detection and care of skin cancer.

About the AAD
Headquartered in Schaumburg, Ill., the American Academy of Dermatology, founded in 1938, is the largest, most influential, and most representative of all dermatologic associations. With a membership of more than 18,000 physicians worldwide, the AAD is committed to advancing the diagnosis and medical, surgical and cosmetic treatment of the skin, hair and nails; advocating high standards in clinical practice, education, and research in dermatology; and supporting and enhancing patient care for a lifetime of healthier skin, hair and nails. The Journal of the American Academy of Dermatology was the third most cited dermatology journal in 2015. For more information, contact the AAD at 1-888-462-DERM (3376) or Follow the Academy on Facebook (American Academy of Dermatology), Twitter (@AADskin) or YouTube(AcademyofDermatology).

About the Academy’s Survey
The survey was conducted by Relevant Research Inc. of Chicago on Jan. 4 and 5, 2016. A total of 1,020 respondents completed the online survey. Data were weighted by sex, age, race/ethnicity and income according to the 2014 U.S. Census Bureau’s American Community Survey for adults ages 18-64. The margin of sampling error at the 95 percent confidence level is ± 3.1 percent. 

Tuesday, May 17, 2016

Study: Regular Exercise at Any Age Might Stave Off Alzheimer’s

Fitness Level Correlates with Increased Blood Flow to Essential Areas of the Brain

Newswise , May 17, 2016-- Recent research suggests that exercise might provide some measure of protection from Alzheimer’s disease and other dementias.

A group of researchers led by Nathan Johnson PT, DPT, PhD of the University of Kentucky College of Health Sciences, was able to demonstrate a positive correlation between fitness and blood flow to areas of the brain where the hallmark tangles and plaques of AD pathology are usually first detected.

Thirty men and women ages 59-69 were put through treadmill fitness assessments and ultrasounds of the heart. Then they received brain scans to look for blood flow to certain areas of the brain.

“We set out to characterize the relationship between heart function, fitness, and cerebral blood flow, which no other study had explored to date,” Johnson said.

“In other words, if you’re in good physical shape, does that improve blood flow to critical areas of the brain? And does that improved blood flow provide some form of protection from dementia?”

The results showed blood flow to critical areas of the brain – and so the supply of oxygen and vital nutrients – was higher in those who were more physically fit.

In layman’s terms, this study demonstrates that regular exercise at any age could keep the mind young, according to Johnson.

“Can we prove irrefutably that increased fitness will prevent Alzheimer’s disease? Not at this point,” Johnson said.

“But this is an important first step towards demonstrating that being physically active improves blood flow to the brain and confers some protection from dementia, and conversely that people who live sedentary lifestyles, especially those who are genetically predisposed to Alzheimer’s, might be more susceptible.”

Since people who exercise frequently often have reduced arterial stiffness, Johnson and his group postulate that regular physical activity – regardless of age – maintains the integrity of the “pipes” that carry blood to the brain.

“In the mid-late 20th century, much of the research into dementias like Alzheimer’s focused on vascular contributions to disease, but the discovery of amyloid plaques and tangles took prevailing research in a different direction” Johnson said.

“Research like this heralds a return to the exploration of the ways the vascular system contributes to the disease process.”

Johnson’s research, which was supported by a grant from the National Institutes of Health CTSA (UL1TR000117) and the University of Kentucky's Clinical Services Core, was published in the current issue of NeuroImage.

In Large Study, Sleep Apnea Associated With Heart Attack, Stroke, and Other Serious Outcomes After Coronary Revascularizatio

Risks from Untreated Sleep ApneaNewswise, May 17, 2016─ In an ongoing prospective study involving 1,311 patients from five nations, researchers found that untreated obstructive sleep apnea (OSA) was associated with increased risk of a Major Adverse Cardiac and Cerebrovascular Event (MACCE) -- cardiovascular death, non-fatal myocardial infarction (heart attack), non-fatal stroke, and unplanned revascularization such as heart bypass surgery and angioplasty.

The new research, from the Sleep and Stent Study, was presented at the ATS 2016 International Conference.

“Patients with OSA in this study were found to have 1.57 times the risk of other patients of incurring an MACCE at a median follow-up of nearly two years,” said Principal Investigator Lee Chi-Hang, MBBS, MD, FCRP (Edin), FACC, FSCAI, of the National University Heart Centre, Singapore.

“This held true after adjusting for other variables including age, sex, ethnicity, body mass index, diabetes and hypertension.”

The study included patients from Singapore, China and Hong Kong, India, Myanmar, and Brazil who had undergone a common artery-widening procedure known as a percutaneous coronary intervention (PCI).

Within seven days of undergoing the PCI, all patients in the study participated in an in-hospital sleep study, using a portable diagnostic device. The sleep studies were manually scored by a committee directed by a sleep physician and Registered Polysomnographic Technologist, both of whom were blinded to the demographic and clinical characteristics of study subjects. The reported MACCEs, along with source documents, were judged by a clinical event committee.

The prevalence of OSA was 45.3%. Although the purpose of the study was to analyze outcomes in untreated OSA patients, patients were still allowed to seek treatment.

Dr. Lee was able to determine that only 1.3% of patients in the study diagnosed with OSA were on regular CPAP therapy at the end of the study. A majority of the 1,311 patients had state-of-the-art drug-eluting stents implanted.

“As OSA is highly prevalent and has a prognostic implication in patients with coronary artery disease, we recommend that all patients scheduled for a PCI be routinely screened for OSA, just as they would be for diabetes mellitus, hypertension and hyperlipidemia,” said Dr. Lee.

“This screening is now more feasible with the advent of reliable portable devices like those used in our study.”

Dr. Lee added, “Since a vast majority of patients were not on CPAP therapy, our findings highlight that there is a significant gap between medical knowledge and clinical practice in the management of OSA. This should receive serious examination.” 

Dr. Lee and colleagues plan continued follow up with study participants to secure long-term outcome data. 

Exacerbations in COPD Patients Hasten Lung Function Loss

Newswise, May 17, 2016 ─ In patients with chronic obstructive pulmonary disease (COPD), exacerbations accelerated lung function loss, according to a new study presented at the ATS 2016 International Conference. 

The effect was particularly prominent in those with mild disease.

The investigators embarked on their research because previous studies failed to adequately examine if exacerbations in patients with mild COPD, or similar acute respiratory events in current and former smokers without airflow obstruction, affect lung decline, said Ken M. Kunisaki, MD, MS, of the Minneapolis VA Health Care System in Minneapolis.

Investigators analyzed data from 2,861 patients in the COPDGene 5-year follow-up cohort study. All COPDGene participants were current or former smokers. Spirometry, used to diagnose COPD and assess lung function, was performed at study entry in all subjects and at follow-up in 2,000 subjects.

Exacerbations were defined as acute respiratory symptoms that required antibiotics or systemic steroids; severe events were defined by the need for hospitalization. (In those without established COPD, the criteria were used to define acute respiratory events.)

Thirty-seven percent of patients reported at least one exacerbation/acute respiratory event. In patients with COPD, each exacerbation was associated with excess loss of lung function, as measured by FEV1—the amount of air a person can forcefully blow out of their lungs in one second.

The investigators saw the greatest excess loss of FEV1 in those with mild COPD. Acute respiratory events were not associated with additional FEV1 decline in subjects who did not have airflow obstruction.

“Our findings are particularly novel due to our large numbers of persons with mild COPD—a group that has not been well studied in previous investigations,” Kunisaki said.

The investigators recommend additional trials to test existing and novel therapies in subjects with early or mild COPD, to potentially reduce the risk for progression to more advanced lung disease.

Meetings with Palliative Care Do Not Improve Anxiety and Depression Symptoms in Family Caregivers of Chronic Critically Ill Patients

Palliative Care Counseling need improvement
Newswise, May 17, 2016– Additional support by palliative care specialists failed to improve anxiety and depression symptoms in caregivers of patients with chronic critical illness, according to new research presented at the ATS 2016 International Conference.

Patients also saw little benefit as the additional support did not lead to reduced time on a breathing machine or in the hospital.

“Family members indicated that they were satisfied with the information and support provided by the ICU physicians, and this may explain why the additional support from palliative care specialists did not improve family or patient outcomes,” said Shannon Carson, MD, of the University of North Carolina at Chapel Hill in Chapel Hill, North Carolina.

The study enrolled 256 adult patients and their caregivers from medical ICUS at three tertiary care centers and one community hospital. To be eligible, patients had to require at least seven days of mechanical ventilation. Patients were randomized to either usual care or two meetings with a palliative care physician and nurse practitioner.

Given that palliative care specialists, who are trained to provide emotional support and share difficult information, are routinely consulted to provide family support and facilitate goals of care discussions for chronically critically ill patients, the authors wanted to determine if these specialists would help to reduce psychological stress for families.

“Findings of our study indicate that routine referral of these patients for palliative care consultation does not improve psychological distress for families as compared to effective communication by ICU physicians,” said Dr. Carson.

“ICU physicians should continue to make communication and support for family decision-makers an important part of their practice in the ICU. They should meet with families early and provide additional support as needed. Support for this physician effort by insurers is a good use of resources.”

Being Fit May Slow Lung Function Decline as We Age

Newswise , May 17, 2016– Being fit may reduce the decline in lung function that occurs as we grow older, according to research presented at the ATS 2016 International Conference.

“While everyone’s lung function declines with age, the actual trajectory of this decline varies among individuals, “ said Lillian Benck, MD, a medical resident at Northwestern University Feinberg School of Medicine, Chicago, Illinois, and study lead investigator. “What is less known is, beyond smoking, what factors affect this rate of decline.”

Dr. Benck added that even though the majority of people will not develop lung disease in their lifetime, “declining lung function is known to increase overall morbidity and mortality even in the absence of overt pulmonary disease.”

Dr. Benck and her colleagues analyzed data from the National Heart, Lung, and Blood Institute’s CARDIA (Coronary Risk Development in Young Adults Study), which began in 1985-86 with 5,115 healthy black and white men and women, aged 18-30. 

The study has measured participant’s cardiopulmonary fitness periodically over 20 years using a graded treadmill test. At the beginning of the study and at each follow-up assessment, pulmonary function (PF) was also assessed by measuring forced expiratory volume in one second (FEV1) and forced vital capacity (FVC).

After adjusting for age, smoking, body mass index and change in BMI, the association between fitness and lung function remained statistically significant.
Researchers found that participants:

• in the top quartile of baseline fitness experienced the least annual decline in PF.
• with the greatest decline in fitness experienced the greatest decline in FEV1and PF over 20 years.
• with sustained or improved fitness experienced the least decline in PF over 20 years.
Dr. Benck said that the last finding is noteworthy because it indicates that fitness matters, not just at a single point in time but over many years. “Fitness early in life and at middle age appears to attenuate this natural decline,” she said, noting that the benefit of fitness was even seen among smokers.

Because it is an observational study, researchers cannot claim cause and effect. However, they noted several important strengths, including a large study population and long-term follow-up and objective measurements of fitness and lung health.

Dr. Benck said that CARDIA will continue to follow participants and may eventually provide insights into whether fitness not only preserves lung function, but also reduces the risk of developing lung disease.

Thursday, May 12, 2016

Mobility Assessment Tool May Help Predict Early Postoperative Outcomes for Older Adults

Mobility Assessment Tool for Older Adults Newswise, May 12, 2016– A quick, reliable and cost-effective mobility assessment tool may help to identify elderly patients at risk for adverse post-surgery outcomes, according to Wake Forest Baptist Medical Center researchers.

In their study of 197 men and woman over age 69 who underwent elective, non-cardiac, inpatient surgery at Wake Forest Baptist over a 20-month period, the researchers found that the participants’ preoperative scores on the Mobility Assessment Tool: Short Form (MAT-sf) were predictive of early postoperative complications, longer hospital stays and discharges to nursing homes.

“Preoperative assessment of patient characteristics that may lead to adverse postoperative outcomes is important to patients, their families and their surgeons, especially with older adults, in whom complications are more likely,” said Leanne Groban, M.D., professor of anesthesiology at Wake Forest Baptist and lead author of the study, published in the April issue of the journal Anesthesiology.

““Mobility is a powerful indicator of overall health in the elderly, and our results indicate that self-reported mobility, as measured by the MAT-sf, can complement existing assessment tools in determining which patients are at risk of adverse postoperative outcomes.”

The MAT-sf features animated video clips of 10 common physical activities, each followed by questions about the participant’s ability to perform the particular task. In addition to the MAT-sf, participants in the study also underwent four other commonly employed preoperative risk assessments.

After controlling for factors such as the participants’ age, sex and body mass index and their scores on the other tests, the researchers found that low (poor) scores on the MAT-sf were associated with short-term complications, later time to discharge and increased nursing home placement to a greater degree than any of the other indicators.

“The traditional risk assessments may be too comprehensive, too focused on single organ systems or too impractical to be effective in this setting,” Groban said.

The next steps, she said, are to validate these findings in a larger, multi-center study and to test whether preoperative strength and balance training might limit undesirable postoperative outcomes in older adults with mobility limitations.

“Studies such as this will help determine future clinical pathways aimed at reducing adverse outcomes while improving patients’ functionality and speeding their return to independence,” Groban said.

Sleep Loss Detrimental to Blood Vessels

Newswise, May 12, 2016 — Lack of sleep has previously been found to impact the activation of the immune system, inflammation, carbohydrate metabolism and the hormones that regulate appetite. Now University of Helsinki researchers have found that sleep loss also influences cholesterol metabolism.

The study examined the impact of cumulative sleep deprivation on cholesterol metabolism in terms of both gene expression and blood lipoprotein levels.

With state-of-the-art methods, a small blood sample can simultaneously yield information about the activation of all genes as well as the amounts of hundreds of different metabolites. This means it is possible to seek new regulating factors and metabolic pathways which participate in a particular function of the body.

"In this case, we examined what changes sleep loss caused to the functions of the body and which of these changes could be partially responsible for the elevated risk for illness," explains Vilma Aho, researcher from the Sleep Team Helsinki research group.

The study established that the genes which participate in the regulation of cholesterol transport are less active in persons suffering from sleep loss than with those getting sufficient sleep.

This was found both in the laboratory-induced sleep loss experiment and on the population level.

While analysing the different metabolites, the researchers found that in the population-level data, persons suffering from sleep loss had fewer high-density HDL lipoproteins, commonly known as the good cholesterol transport proteins, than persons who slept sufficiently.

Together with other risk factors, these results help explain the higher risk of cardiovascular disease observed in sleep-deprived people and help understand the mechanisms through which lack of sleep increases this risk.

"It is particularly interesting that these factors contributing to the onset of atherosclerosis, that is to say, inflammatory reactions and changes to cholesterol metabolism, were found both in the experimental study and in the epidemiological data," Aho says.

The results highlight the health impact of good sleep. The researchers emphasise that health education should focus on the significance of good, sufficient sleep in preventing common diseases, in addition to healthy food and exercise.

Even a small reduction in illnesses, or even postponing the onset of an illness, would result in significant cost savings for society at large.

"The experimental study proved that just one week of insufficient sleep begins to change the body's immune response and metabolism. Our next goal is to determine how minor the sleep deficiency can be while still causing such changes," Aho states.

The Sleep Team Helsinki research group, led by Dr. Tarja Porkka-Heiskanen (Stenberg), is studying the impact of sleep loss on immune defence and metabolism, particularly lipid and cholesterol metabolism. 

It has previously been established through epidemiological studies that people who sleep less than they should have a higher risk of contracting cardiovascular diseases, a higher risk of mortality from cardiovascular diseases, and a higher overall mortality over a set time span.

Cardiovascular diseases are known to be linked to both metabolism and the immune system. Sleep loss has been demonstrated to cause low-grade inflammatory state in the body, and this may contribute to the higher risk of disease. Carbohydrate metabolism has also been found to alter in sleep deficiency in ways that resemble type 2 diabetes.

However, the impact of sleep loss on lipid and cholesterol metabolism has been studied very little.