Monday, June 21, 2021

Sleep apnea worsens heart disease, yet often untreated

American Heart Association scientific statement


Research News

DALLAS, June 21, 2021 — Health care experts urge increased awareness of obstructive sleep apnea among people with cardiovascular disease or risk factors such as high blood pressure, according to a new scientific statement from the American Heart Association, published today in Circulation, the Association’s flagship journal.

Obstructive sleep apnea (OSA) occurs in 40% to 80% of people with cardiovascular disease, yet it is under-recognized and undertreated, according to the statement. OSA occurs when an upper airway obstruction causes repeated episodes of disrupted breathing during sleep. Symptoms include snoring, lapses in breathing, fragmented sleep and daytime sleepiness. In general, about 34% of middle-aged men and 17% of middle-aged women meet the criteria for OSA.

“Obstructive sleep apnea can negatively impact patients’ health and increase the risk of cardiovascular events and death. This statement is to encourage increased awareness, screening and treatment as appropriate for sleep apnea,” said Chair of the scientific statement writing group Yerem Yeghiazarians, M.D., FAHA, professor of medicine and the Leone-Perkins Family Endowed Chair in Cardiology at the University of California, San Francisco. 

Risk factors for OSA include obesity, large neck circumference, craniofacial abnormalities, smoking, family history and nighttime nasal congestion. OSA is associated with several cardiovascular complications, as detailed in Figure 2 of the statement:

  • high blood pressure – OSA is present in 30-50% of people with high blood pressure, and up to 80% of those who have resistant, or hard-to-treat high blood pressure;
  • heart rhythm disorders such as atrial fibrillation and sudden cardiac death;
  • Stroke;
  • worsening heart failure;
  • worsening coronary artery disease and risk of heart attack;
  • Pulmonary hypertension (PH) – as many as 80% of people with PH have OSA; and
  • Metabolic syndrome and Type 2 diabetes.

While there’s no consensus that screening for OSA alters clinical outcomes, the high prevalence of OSA among people with cardiovascular disease, along with evidence that OSA treatment improves patient quality of life, are reasons to screen and provide treatment, according to the statement writing group.

“Patients report better mood, less snoring, less daytime sleepiness, improved quality of life  and work productivity with OSA treatment,” Yeghiazarians said. “In addition, screening advances have changed how we diagnose and treat obstructive sleep apnea. For example, many patients do not have to go to an overnight sleep study center anymore. There are now sleep devices approved by the FDA that patients use at home and send back to their doctor for assessment. And, while a continuous positive airway pressure (CPAP) machine is one form of treatment, there are numerous therapeutic options - from positional therapy and weight loss to oral appliances and surgery - depending on the cause and severity of someone’s OSA.”

The authors suggest:

  • Screening for OSA in patients with resistant or difficult to control hypertension, pulmonary hypertension and atrial fibrillation that recurs despite treatment.
  • Screening for OSA via a sleep study for some patients with heart failure, especially if sleep-disordered breathing or excessive daytime sleepiness are suspected.
  • Treating patients diagnosed with OSA with available therapies, potentially including lifestyle and behavior modifications and weight loss.
  • When possible, treating patients with severe OSA with a CPAP machine.
  • Treating mild to moderate OSA cases with oral appliances that adjust the jaw and tongue placement during sleep to prevent obstructed breathing.
  • Routine follow-up including overnight sleep testing to confirm if treatment is effective.

“Improvements in home diagnostic tools and more research on ways to identify cardiovascular risk in people with OSA are needed,” Yeghiazarians said. “Still, the overall message is clear: we need to increase awareness about screening for and treating OSA, especially in patients with existing cardiovascular risk factors.”

This scientific statement was prepared by the volunteer writing group on behalf of the American Heart Association’s Council on Clinical Cardiology; the Council on Peripheral Vascular Disease; the Council on Arteriosclerosis, Thrombosis and Vascular Biology; the Council on Cardiopulmonary, Critical Care, Perioperative and Resuscitation; the Stroke Council; and the Council on Cardiovascular Surgery and Anesthesia. 

Potato nutrients can help reduce sodium retention, may help reduce risk of hypertension

New study finds that individuals with higher cardiometabolic risk may benefit from adding more dietary potassium, via potatoes, to a typical American diet


Research News

June 21, 2021 -- A new study published in Nutrients investigated the effect of increased dietary potassium from a whole food source--baked/boiled potatoes and baked French fries--or a potassium supplement on blood pressure and other cardiovascular disease risk factors compared to a 'typical American' control diet (lower potassium intake) among 30 pre-hypertensive to hypertensive men and women. Results showed that including baked/boiled potato consumption as part of a typical American diet had the greatest benefit on reducing sodium retention, even more than the supplement, and resulted in a greater systolic blood pressure reduction compared to the control diet. Further, despite commonly held misbeliefs about French fries and their role in heart-healthy lifestyles, the authors observed that a 330-calorie serving of baked French fries, when eaten as part of a typical American diet, had no adverse effect on blood pressure or blood vessel function.

"While significant emphasis is often placed on reducing dietary sodium intakes to better control for blood pressure and cardiovascular disease risk, that's only half of the story," says Connie Weaver, PhD, the primary investigator. "Potassium plays just as an important role, and perhaps the ratio of potassium to sodium is most important in the context of the entire food matrix, as the potato meal resulted in a greater reduction of sodium retention than the potassium supplement alone."

Evidence on the effect of increased dietary potassium on blood pressure from clinical trials is extremely limited, and this is one of the first known controlled feeding interventions investigating dietary potassium as the primary variable of interest.

"It's important to establish clinical trials that follow observational research to establish a causal link between diet and health," notes Weaver. "For example, in this clinical study baked French fries had a null effect on blood pressure, which counters observational findings, at least in the short term, and helps to prioritize the importance of focusing on a total diet approach for maintaining health versus one that overemphasizes avoidance of any single food or food group."

Potatoes comprise roughly 20 percent of the vegetable intake in the American diet and help fill several nutrient gaps, including dietary fiber and potassium.1 Eating just one medium potato meets approximately 10 percent of an adult's daily potassium needs. According to the 2020-2025 Dietary Guidelines for Americans, potassium is an essential nutrient of concern, indicating most Americans aren't consuming enough. The mineral has been linked to improvements in cardiovascular and other metabolic health outcomes - including decreased blood pressure in those with hypertension. Overall, potatoes and French fries represent about 7 percent and 3 percent of potassium intake, respectively, in the United States.1

"Considering Americans fall significantly short in meeting daily potassium intakes, these findings show the importance of promoting, not restricting, whole food good-to-excellent sources of potassium in Americans' diets, like potatoes," Weaver said.

A Closer Look at the Study Methodology, Strengths and Limitations

Participants were randomly assigned to one of four 16-day dietary potassium interventions:

  • Control diet including 2300 mg potassium/day (reflective of typical intake, considered to be 'low potassium')
  • Control diet + 1000 mg of potassium from potatoes (baked, boiled, or pan-heated with no additional fat)
  • Control diet + 1000 mg from baked French fries
  • Control diet + 1000 mg from a potassium-gluconate supplement

Each diet was tailored to participants' specific caloric needs while all other nutrients were kept constant. Blood pressure was measured across multiple visits of each phase, and participants also collected daily urine/stool samples to assess potassium and sodium excretion and retention.

The strengths of the study include a highly controlled diet, cross-over design, and excellent compliance. However, the researchers note a few limitations as well, including the study's relatively small sample size, poor retention in study participation and relatively short study duration.

"All clinical studies are faced with limitations; however, despite those found in this study, the rigor of the study design is strong and unlike any other studies that have investigated the effect of a whole food - and potassium - on high blood pressure," Weaver notes. "Through our carefully controlled balance study, we could determine the mechanism by which potatoes reduced blood pressure. Overall, we concluded that boiled or baked potatoes can help reduce systolic blood pressure - and baked French fries have no adverse effects on blood pressure and can be included as part of an overall healthy diet."

The research manuscript, "Short-term randomized controlled trial of increased dietary potassium from potato or potassium gluconate: effect on blood pressure, microcirculation, and potassium and sodium retention in pre-hypertensive-to-hypertensive adults," is published in Nutrients (doi: Authors include Michael Stone, Berdine Martin and Connie Weaver of Purdue University. Funding was provided by the Alliance for Potato Research and Education.

Thursday, June 17, 2021

FDA advisory panelist outlines numerous issues with aducanumab's accelerated approval for Alzheimer's disease

Despite near unanimous objection from its advisory panel, the U.S. Food and Drug Administration (FDA) granted aducanumab approval to treat Alzheimer's disease on June 7, 2021. In a commentary published in Annals of Internal Medicine, a member and former Chair of the advisory panel and an aducanumab site investigator explain why this unprecedented "accelerated approval" is problematic for clinical research and patient care.

Under accelerated approval, a drug is approved based on its effect on a surrogate marker of a disease rather than clinical outcomes. The product is expected to provide a meaningful advantage over other available therapies for a serious disease. Aducanumab's phase 1 study indicates the drug reduces beta-amyloid (the surrogate marker of disease), but whether beta-amyloid alone is a valid surrogate for the treatment of Alzheimer's is notably unclear and still a topic of ongoing important study. With the surprising approval, treating an amyloid level becomes clinical practice.

The authors express grave concern that aducanumab's approval will have important consequences for drug development, regulation, and patient care. While the world waits for the results of randomized and controlled clinical trials required to confirm aducanumab's clinical benefits (or not), insurers and payers will have to use the scant information available to determine which patients should take it and how to cover it. The copays for aducanumab, which may be as much as 20% of the total cost, will be added to the already substantial financial burden many American families face due to Alzheimer's disease. Also, clinicians will have to address with patients, uncertainty regarding whether the drug is even beneficial or safe.

According to the authors, the effect of aducanumab's approval will reverberate for years. Patients, caregivers, providers, and scientists must navigate treatment of Alzheimer's disease with an uncertain treatment. Time will tell whether or not it is safe and effective.

Wednesday, June 16, 2021

Intermittent fasting 'no magic bullet for weight loss' says new study

Research News

New research published this week challenges a popular belief that intermittent fasting diets such as alternate day fasting or the '5:2' are the most effective ways to lose weight.

Over recent years, diets which see people fast on a few days each week have increased in popularity, reinforced by images of people's miraculous weight transformations, and backed by celebrity endorsements.

However, evidence to date about the effectiveness of fasting compared with more traditional diets which aim to reduce calorie intake over the course of a full week has been limited.

Published in the prestigious journal Science Translational Medicine, the new study from a team of physiologists at the University of Bath builds this evidence and indicates that there is 'nothing special' about fasting.

Participants in their randomised control trial lost less weight when fasting in comparison with those following a traditional diet - even when their calorie intake was the same overall.

The trial, organised by a team from the University's Centre for Nutrition, Exercise & Metabolism (CNEM), saw participants allocated into one of three groups:

  • Group 1 which fasted on alternate days with their fast day followed by a day of eating 50% more than usual.
  • Group 2 which reduced calories across all meals everyday by 25%.
  • Group 3 which fasted on alternate days (in the same way as Group 1) but followed their fast day with one day eating 100% more than usual.

Participants across all three groups were consuming a typical diet of around 2000-2500 kcal per day on average at the start of the study. Over the course of the three-week monitoring period, the two energy restricted groups reduced this to be between 1500-2000 kcal on average. Whereas groups 1 and 2 reduced their calorie intake by the same amount in different ways, group 3's diet saw them fast without reducing overall calories.

Their results found that the non-fasting dieting group (Group 2) lost 1.9 kg in just three weeks, and DEXA body scans revealed this weight loss was almost entirely due to a reduction in body fat content.

By contrast, the first fasting group (Group 1) who experienced the same reduced calorie intake by fasting on alternate days and eating 50% more on non-fasting days, lost almost as much body weight (1.6 kg) but only half this weight loss was from reduced body fat with the remainder from muscle mass.

Group 3, who fasted but increased their energy intake by 100% on non-fasting days, did not need to draw on their body's fat stores for energy and therefore weight loss was negligible.

Professor James Betts, Director of the Centre for Nutrition, Exercise & Metabolism at the University of Bath who led the research explains: "Many people believe that diets based on fasting are especially effective for weight loss or that these diets have particular metabolic health benefits even if you don't lose weight.

"But intermittent fasting is no magic bullet and the findings of our experiment suggest that there is nothing special about fasting when compared with more traditional, standard diets people might follow.

"Most significantly, if you are following a fasting diet it is worth thinking about whether prolonged fasting periods is actually making it harder to maintain muscle mass and physical activity levels, which are known to be very important factors for long-term health."

These results focused on participants who were defined as 'lean' (i.e. body mass index 20-25 kg/m2). 36 people participated in the study which was conducted between 2018 - 2020 and funded by the University of Bath.

Alternate-day intermittent fasting leads to less fat loss than traditional daily energy restriction


Research News

An alternate-day intermittent fasting schedule offered less fat-reducing benefits than a matched "traditional" diet that restricts daily energy intake, according to a new, 3-week randomized trial involving 36 participants. The study, which is one of the first to tease apart the effects of fasting and daily energy restriction in lean individuals, indicates that alternate-day fasting may offer no fasting-specific health or metabolic benefits over a standard daily diet. However, the authors caution that longer studies with larger groups are needed. Intermittent fasting, which involves cycling through voluntary fasting and non-fasting periods, has become one of the most popular approaches to losing weight. There are many different intermittent fasting schedules, ranging from fasting for part of each day to the popular 5:2 diet (eating 5 days a week and fasting 2 days) to alternate-day fasting (eating one day, fasting the next). Many participants report that fasting schedules are relatively easy to adopt and stick by, and theories suggest that fasting can trigger beneficial changes in metabolism that encourage weight loss. However, few studies have examined the fasting-specific effects of intermittent fasting or compared its effects to diets that simply reduce daily net calories. 

Iain Templeman and colleagues recruited 36 lean participants and split them into 3 groups of 12, who followed different diets for 3 weeks. The first group followed a restricted, alternate-day fasting diet (eating 150% of their habitual daily energy intake only every other day), the second group followed an energy-matched non-fasting diet with 75% daily energy intake, and the last group followed an alternate-day fasting diet with no restriction in energy intake (200% daily energy intake every other day). After 3 weeks, the second group showed the greatest losses of both weight and fat, with an average fat loss of 1.57 kg. Meanwhile, the first group of alternate-day fasters lost weight but lost fat less effectively (an average of .74 kg), and the last group showed no significant drops in either weight or fat. Further studies showed there were no key differences in cardiometabolic health, metabolic molecules, or gene expression in fat cells between the 3 groups. 

Templeman et al. noted that the alternate-day fasters tended to be less active than before starting the diet, hinting at one factor that may have impacted fat loss. The authors speculate that individuals considering alternate-day fasting should make sure to include opportunities for physical activity to maintain their energy expenditure.

Tuesday, June 15, 2021

Use of PFAS in cosmetics 'widespread,' new study finds





Many cosmetics sold in the United States and Canada likely contain high levels of per- and polyfluoroalkyl substances (PFAS), a potentially toxic class of chemicals linked to a number of serious health conditions, according to new research from the University of Notre Dame.

Scientists tested more than 200 cosmetics including concealers, foundations, eye and eyebrow products and various lip products. According to the study, 56 percent of foundations and eye products, 48 percent of lip products and 47 percent of mascaras tested were found to contain high levels of fluorine, which is an indicator of PFAS use in the product. The study was recently published in the journal of Environmental Science and Technology Letters.

"These results are particularly concerning when you consider the risk of exposure to the consumer combined with the size and scale of a multibillion-dollar industry that provides these products to millions of consumers daily," Graham Peaslee, professor of physics at Notre Dame and principal investigator of the study, said. "There's the individual risk -- these are products that are applied around the eyes and mouth with the potential for absorption through the skin or at the tear duct, as well as possible inhalation or ingestion. PFAS is a persistent chemical -- when it gets into the bloodstream, it stays there and accumulates. There's also the additional risk of environmental contamination associated with the manufacture and disposal of these products, which could affect many more people."

Previously found in nonstick cookware, treated fabrics, fast food wrappers and, most recently, the personal protective equipment used by firefighters across the country, PFAS are known as "forever chemicals," because the chemical compounds don't naturally degrade -- which means they end up contaminating groundwater for decades after their release into the environment. Use of PFAS in foam fire suppressants has been linked to contaminated drinking water systems, prompting the Department of Defense to switch to environmentally safer alternatives, for example.

Studies have linked certain PFAS to kidney cancer, testicular cancer, hypertension, thyroid disease, low birth weight and immunotoxicity in children.

Peaslee and the research team tested products purchased at retail locations in the United States as well as products purchased online in Canada. The study found high levels of fluorine in liquid lipsticks, waterproof mascaras and foundations often advertised as "long-lasting" and "wear-resistant." Peaslee said this not entirely surprising, given PFAS are often used for their water resistance and film-forming properties.

What is more concerning is that 29 products with high fluorine concentrations were tested further and found to contain between four and 13 specific PFAS, only one of these items tested listed PFAS as an ingredient on the product label.

"This is a red flag," Peaslee said. "Our measurements indicate widespread use of PFAS in these products -- but it's important to note that the full extent of use of fluorinated chemicals in cosmetics is hard to estimate due to lack of strict labeling requirements in both countries."

Peaslee's novel method of detecting PFAS in a wide variety of materials has helped reduce the use of "forever chemicals" in consumer and industrial products.

Following a study from his lab in 2017, fast food chains that discovered their wrappers contained PFAS switched to alternative options. Peaslee continues to receive samples of firefighter turnout gear from fire departments around the world to test for PFAS, and his research has spurred conversations within the firefighter community to eliminate use of "forever chemicals" in various articles of personal protective equipment.

Adults who skip morning meal miss out on nutrients, study finds

Research News

An analysis of data on more than 30,000 American adults showed that skipping breakfast - and missing out on the calcium in milk, vitamin C in fruit, and the fiber, vitamins and minerals found in fortified cereals - likely left adults low on those nutrients for the entire day.

"What we're seeing is that if you don't eat the foods that are commonly consumed at breakfast, you have a tendency not to eat them the rest of the day. So those common breakfast nutrients become a nutritional gap," said Christopher Taylor, professor of medical dietetics in the College of Medicine at The Ohio State University and senior author of the study.

According to the U.S. Department of Agriculture's latest dietary guidelines, calcium, potassium, fiber and vitamin D are considered "dietary components of public health concern" for the general U.S. population - with iron added for pregnant women - because shortages of those nutrients are associated with health problems.

Most research related to breakfast has focused on the effects of the missed morning meal on children in school, which includes difficulty focusing and behavioral problems.

"With adults, it's more like, 'You know how important breakfast is.' But now we see what the implications really are if they miss breakfast," Taylor said.

He completed the study with Ohio State School of Health and Rehabilitation Sciences graduate students Stephanie Fanelli and Christopher Walls. The research, which was supported by a regional dairy association, is published online in Proceedings of the Nutrition Society.

The team used data from the National Health and Nutrition Examination Survey (NHANES), which collects health information on a nationally representative sample of about 5,000 people every year through interviews, laboratory tests and physical exams.

The sample for this study included 30,889 adults age 19 and older who had participated in the survey between 2005 and 2016. The Ohio State researchers analyzed data from 24-hour dietary recalls participants completed as part of the NHANES survey.

"During the recall, participants self-designate their eating occasions as a meal or a snack, and they tell you at what point in time they ate whatever food they report," said Fanelli, first author of the study. "That's how we determined whether someone was a breakfast eater or a breakfast skipper."

In this sample, 15.2% of participants, or 4,924 adults, had reported skipping breakfast.

The researchers translated the food data into nutrient estimates and MyPlate equivalents using the federal Food and Nutrient Database for Dietary Studies and daily dietary guidelines, and then compared those estimates to recommended nutrient intakes established by the Food and Nutrition Board of the National Academies.

On several key recommendations measured, from fiber and magnesium to copper and zinc, breakfast skippers had taken in fewer vitamins and minerals than people who had eaten breakfast. The differences were most pronounced for folate, calcium, iron, and vitamins A, B1, B2, B3, C and D.

"We found those who skipped breakfast were significantly more likely not to meet the bottom threshold of what we hope to see people eat," Fanelli said.

Compared to the Healthy Eating Index-2015, which assesses how well a set of foods aligns with federal recommendations, breakfast skippers also had an overall lower-quality diet than those who ate breakfast.

For example, breakfast skippers were more likely than those who noshed in the morning to eat more added sugars, carbohydrates and total fat over the course of the day - in part because of higher levels of snacking.

"Snacking is basically contributing a meal's worth of calorie intakes for people who skipped breakfast," Taylor said. "People who ate breakfast ate more total calories than people who didn't eat breakfast, but the lunch, dinner and snacks were much larger for people who skipped breakfast, and tended to be of a lower diet quality."

While the data represent a single day in each participant's life, the huge sample provides a "nationally representative snapshot for the day," Taylor said.

"It shows that those who skipped breakfast had one nutrient profile and those who ate breakfast had a different nutrient profile," he said. "It helps us identify on any given day that this percentage of people are more likely to be skipping breakfast. And on that day, their dietary intake pattern showed that their consumption didn't capture those extra nutrients that they have basically missed at breakfast."