Tag Archives: #hypertension

Potato Nutrients Can Help Reduce Sodium Retention, May Help Reduce Risk of Hypertension (Food)

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

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: https://doi.org/10.3390/nu13051610). Authors include Michael Stone, Berdine Martin and Connie Weaver of Purdue University. Funding was provided by the Alliance for Potato Research and Education.

Reference: Stone, M.S.; Martin, B.R.; Weaver, C.M. Short-Term RCT 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. Nutrients 2021, 13, 1610. https://doi.org/10.3390/nu13051610

Provided by Alliance for Potato Research and Education

Plant-based Diet Protects From Hypertension, Preeclampsia (Food)

A plant-based diet appears to afford significant protection to rats bred to become hypertensive on a high-salt diet, scientists report. When the rats become pregnant, the whole grain diet also protects the mothers and their offspring from deadly preeclampsia.

Although we have all heard to avoid the salt shaker, an estimated 30-50% of us have a significant increase in blood pressure in response to high-salt intake, percentages that are even higher and more impactful in Blacks.

The two new studies provide more evidence that the gut microbiota, which contains trillions of microorganisms that help us digest food and plays a key role in regulating the response of our immune system, is also a player in the unhealthy response to salt, investigators at the Medical College of Georgia and Medical College of Wisconsin report in the journals ACTA PHYSIOLOGICA and Pregnancy Hypertension: An International Journal of Women’s Cardiovascular Health.

The findings provide more evidence of the “potential power” of nutritional intervention to improve the gut microbiota, and consequently our long-term health, says Dr. David L. Mattson, chair of the MCG Department of Physiology, Georgia Research Alliance Eminent Scholar in Hypertension and senior author on the two studies.

They result from the unexpected observation that the protection works even in a well-established model of salt-sensitive hypertension: The Dahl salt sensitive rat.

As their name indicates, these rodents are bred to develop hypertension and progressive kidney disease on a high-salt diet. In 2001, the Medical College of Wisconsin shared their colony of Dahl SS rats, who were fed a milk-based protein diet, with Charles Rivers Laboratories. Once the rats arrived as Charles River Laboratories, headquartered in Wilmington, Massachusetts, they were switched to a grain-based diet. Both diets are relatively low in sodium, although the protein, or casein-based, diet actually has a little less salt.

It was soon noted that when high-salt content was added to their diet, the relocated rodents developed significantly less high blood pressure and related kidney damage than the rat colonies that remained in Wisconsin.

“People ordered them and used them with the idea that they were going to study hypertension and they developed next to none,” Mattson says. More than a decade of research documented these differences, Mattson and his colleagues at MCG and MCW write, and now has shown them that developing salt-sensitive hypertension isn’t just about sodium consumption.

“The animal protein amplified the effects of the salt,” says Mattson, a longtime hypertension researcher, who along with Dr. Justine M. Abais-Battad, physiologist, and postdoc Dr. John Henry Dasinger, came to MCG from Wisconsin two summers ago.

“Since the gut microbiota has been implicated in chronic diseases like hypertension, we hypothesized that dietary alterations shift the microbiota to mediate the development of salt-sensitive hypertension and renal disease,” they write in the journal ACTA PHYSIOLOGICA.

The gut microbiome is designed to metabolize what we eat, break it down and put it in a form that gives us nutrition, first author Abais-Battad says, and reciprocally it reflects what we eat.

When they looked at the microbiomes in the rats: “Sure enough, they were different,” she says.

They sequenced the genetic material of both rat colonies and found they were “virtually identical,” but their response to a high-salt diet was anything but, Mattson says.

As they anticipated at this juncture, the Wisconsin rats developed renal damage and inflammation — both indicators of high blood pressure — but on the same high-salt diet, the Charles River rats experienced significantly less of these unhealthy results. The distinct differences they saw in their microbiota, reflected the difference in disease incidence and severity.

When they gave the protected rats some of the distinctive gut microbiota from the Wisconsin rats, via fecal transplant, the rats experienced increases in blood pressure, kidney damage and in the number of immune cells moving into the kidneys, organs which play a huge role in blood pressure regulation by regulating fluid balance, in part by determining how much sodium is retained. It also changed the composition of their microbiota.

But when they shared the microbiota of the protected rats with the Wisconsin rats, it didn’t have much impact, potentially because the new microorganisms couldn’t flourish in the face of the animal-based protein diet, the scientists say.

Preeclampsia is a potentially lethal problem during pregnancy where the mother’s blood pressure, which typically was normal before, soars and organs like the kidneys and liver show signs of damage. There is evidence that even on a low-salt diet, Dahl salt sensitive rats are inclined to develop preeclampsia.

To look at the impact of diet in this scenario, the Dahl SS rats were kept on their respective plant- or animal-based protein diet, which again are each relatively low salt, and both groups had three separate pregnancies and deliveries.

Rats on the whole wheat based-chow were protected from preeclampsia while about half of the rats on the animal-based casein diet developed this significant complication of pregnancy, says Dasinger, first author on the preeclampsia study. They experienced a significant increase in the protein spilled into their urine, an indicator of kidney trouble, which worsened with each pregnancy; increased inflammation, a driver of high blood pressure; increased pressure inside the renal artery; and showed significant signs of kidney destruction when the organs were studied on follow up. They died of problems like stroke, kidney disease and other cardiovascular problems.

“This means that if mom is careful with what she eats during pregnancy, it will help during the pregnancy, but also with her long-term health and could provide protective effects for her children,” Dasinger says. The scientists note this reinforces the message that physicians and scientists alike have been sending mothers-to-be for decades.

They plan to look more directly at the impact of diet on offspring and whether protection is passed to the babies through breast milk, Dasinger says. Since they know that the function of immune cells is affected by diet, they also want to look further at the function of the immune cells that show up and already have some evidence that T cells, drivers of the immune response, are a factor in the development of preeclampsia.

The work Abais-Battad, Dasinger and Mattson already have done shows that a key difference the different diets yield is the protein-based diet results in production of more proinflammatory molecules, where the plant-based diet actually seems to suppress these factors.

They also are further exploring the impact of diet of the renin-angiotensin system, which helps regulate blood pressure. They also want to better dissect the blood pressure-raising bacteria and the factors they produce.

High blood pressure is the largest modifiable risk factor for development of cardiovascular disease, and, according to the newest guidelines from groups like the American Heart Association, which say a systolic, or top number of 120+ is elevated and top numbers of 130-139 is stage one hypertension, nearly half of us are hypertensive. Diet — including a high-salt diet — is one of the top modifiable risk factors for high blood pressure and cardiovascular disease, the scientists say. Hypertensive humans and animals alike have been found to have an unbalanced, less diverse gut microbiota than those with normal blood pressure.

The research was supported by the National Heart, Lung and Blood Institute, the American Heart Association and the Georgia Research Alliance.

Read the studies here and here.

Featured image: (from left) Drs. John Henry Dasinger, Justine M. Abais-Battad and David L. Mattson. © Michael Holahan, Augusta University

Provided by Medical University of Georgia at Augusta University

Do β-Blockers Cause Depression? (Psychiatry)

Meta-analysis of potential psychiatric side effects

Drugs such as beta-adrenergic antagonists (beta blockers) have been linked to a range of adverse effects, including depression. But how reliable are these data, and which psychiatric side effects might indeed be caused by these drugs? These questions have been addressed by a team of researchers from Charité – Universitätsmedizin Berlin, whose comprehensive meta-analysis has been published in Hypertension*. While treatment with beta blockers was not found to be associated with an increased incidence of depression, some studies recorded higher levels of sleep disturbance.

Beta-adrenergic antagonists such as metoprolol or propranolol are among the drugs most commonly prescribed for the treatment of cardiovascular disease. Their effect is to slow the heart rate and reduce blood pressure, which is why they are used in patients with heart failure, arrhythmias, and high blood pressure. Beta blockers have repeatedly been linked to an increased risk of depression, but also other side effects such as anxiety, sleep disturbance and hallucinations; these links had not previously been explored in a systematic manner.

“We found no evidence to suggest a link between the use of beta blockers and depression,” says Prof. Dr. Reinhold Kreutz, Director of Charité’s Institute of Clinical Pharmacology and Toxicology. “The same also goes for most of the other psychiatric symptoms described in the studies included in our analysis.” Continuing his description of the meta-analysis conducted by his team – the first to study the full range of psychiatric side effects – he adds: “However, some patients developed sleep-related symptoms during treatment with beta blockers.” The researchers analyzed data from more than 53,000 persons. These were taken from 285 individual studies and involved 24 different beta blockers. Only data from double-blind, randomized, controlled trials were included in the analysis. The majority of these related to high blood pressure and had been conducted more than 20 years ago.

Despite being the most commonly reported psychiatric side effect, depression did not occur more frequently during treatment with beta blockers than during treatment with a placebo. Prof. Kreutz, currently President of the European Society of Hypertension, explains: “Patients with a history of cardiovascular problems such as heart attack or stroke are per se prone to develop mental health complications. This means that, while we found no causal link for this problem with beta blockers, these patients should be anyway monitored in this regard in clinical practice.” Patients treated with beta blockers were no more likely to discontinue their medications due to depression than patients undergoing different treatments. However, drowsiness and fatigue were the most commonly reported reasons for discontinuing treatment. Among the other side effects studied – such as anxiety and loss of appetite, memory, or libido – only sleep disturbance and abnormal dreams were found to be linked with beta blockers.

Summing up the results of the research, Prof. Kreutz says: “Our results show that concerns regarding undesirable psychiatric effects, in particular depression, should not influence the decision-making process regarding the use of beta blockers. For the most part, beta blockers have a good psychiatric safety profile.” Therefore, concerns about psychological health should not affect the clinical use of beta-blockers.

Reference: Riemer TG et al. Do β-blockers cause depression? Systematic review and meta-analysis of psychiatric adverse events during β-blocker therapy. Hypertension (2021), doi: 10.1161/HYPERTENSIONAHA.120.16590.

Provided by Charité University, Berlin

How Hypertension Leads To Atherosclerosis? (Medicine)

Research scientists at Aarhus University and Aarhus University Hospital have investigated the mechanisms by which hypertension leads to arterial damage and atherosclerosis. The results may facilitate the development of new therapies.

Hypertension is a prevalent condition affecting approximately one third of all adults. It is also the leading global cause of morbidity and mortality. The condition is often asymptomatic, but over time it may damage arteries causing atherosclerosis and possibly leading to stroke and heart attack.

Despite the prevalence of the disease and its potentially severe consequences, how hypertension leads to atherosclerosis has been poorly understood. In a study from Aarhus University and Aarhus University Hospital, an international team of researchers have identified several steps in this proces. The study was conducted in pigs, due to the similarities between the cardiovascular systems of pigs and humans.

“One of our primary findings is that hypertension is able to exert its detrimental effect on the artery wall through direct mechanical pressure, without the involvement of hormones carried around the bloodstream”, says the lead author behind the study, Rozh Al-Mashhadi, associate professor and radiologist at AU and AUH. 

He adds that the question of whether the arterial damage is caused by high pressure per se or via the involvement of hormones, has been the topic of discussion in the research community for decades.

Unveiling the mechanisms behind hypertension-induced atherosclerosis has important implications: 

“We have several treatments for hypertension aiming at reducing blood pressure to normal levels. However, this may not be adequately maintained in all patients. In order to develop new therapies, we need to clarify the mechanisms by which hypertension damages the arterial wall,” he explains.

Leads to increased accumulation of bad cholesterol

The researchers have also identified the fundamental step linking hypertension to atherosclerosis. The team demonstrated that hypertension leads to increased accumulation of a bad form of cholesterol – so-called LDL cholesterol – in the arterial wall. Rozh Al-Mashhadi explains that this type of cholesterol is pivotal for the development of atherosclerosis.

Finally, the researchers investigated how hypertension leads to increased accumulation of cholesterol in the artery wall:

“We used a technique that simultaneously quantifies all proteins in the artery wall. We found that hypertension caused structural changes in the arterial wall, reducing the transport of proteins from the blood into wall itself. Like in a sieve where the holes are too small, this may explain why we see increased cholesterol accumulation leading to atherosclerosis,” says Rozh Al-Mashhadi.

The results were published in the Journal of the American College of Cardiology. The study may aid in developing new therapies for hypertensive individuals.  

“The new findings may enable us to devise treatment strategies targeting the newly discovered disease mechanisms. Hypertension and atherosclerosis are major health concerns, so there is a lot at stake,” says Rozh Al-Mashhadi. 

About the study:

  • Type of study: Translational research
  • Collaborators: Professor Jacob Bentzon, Department of Clinical Medicine, Aarhus University; Professor Erling Falk, Department of Clinical Medicine, Aarhus University; Professor Jesús Vázquez, Spanish National Cardiovascular Research Center, Madrid, Spain.
  • Funding: Independent Research Fund Denmark, Danish Heart Foundation, Lundbeck Foundation.
  • Read the scientific paper here

Reference: Rozh H. Al-Mashhadi, Ahmed L. Al-Mashhadi, et al., “Local Pressure Drives Low-Density Lipoprotein Accumulation and Coronary Atherosclerosis in Hypertensive Minipigs”, J Am Coll Cardiol. 2021 Feb, 77 (5) 575–589. https://www.jacc.org/doi/abs/10.1016/j.jacc.2020.11.059

Provided by Aarhus University

Big Causes of Heart Failure in COVID-19 Patients Include Obesity, Hypertension (Medicine)

Poor heart health may be key driver for worsening rates of heart failure during pandemic

Key contributors of heart failure in COVID-19 patients will likely be due to pre-existing risk factors, such as obesity and hypertension, that portend worse outcomes with the virus, reports a new Northwestern Medicine Viewpoint.

Currently, a leading concern is that the virus directly attacks the heart leading to inflammation or myocarditis with the potential to cause lasting damage to the heart muscle, the authors said. 

“But that direct attack to the heart, or myocarditis, causing clinically significant heart dysfunction and heart failure has only been observed in a minority of people infected with COVID-19,” said senior study author Dr. Sadiya Khan, assistant professor of preventive medicine at Northwestern University Feinberg School of Medicine and a Northwestern Medicine cardiologist. “What remains unclear is if findings of myocarditis on imaging tests with minimal or without symptoms will have long-lasting health effects.” 

The paper synthesized data from six papers investigating the relationship between COVID-19 and heart effects.

The paper was published today, Sept. 30, in the Journal of the American Medical Association.

“I want to reframe the discussion to the bigger burden of poor heart health, which affects far more people with COVID-19,” Khan said. “People with obesity or hypertension are more likely to get COVID-19, are more likely to have a severe case and are more likely to have cardiovascular complications even without direct heart injury or myocarditis.”

“It may be the virus amplifies the poor heart health that already exists and was worsening in the U.S. population,” Khan said. “It is known the virus can prompt the release of inflammatory molecules throughout the body. This may affect the heart indirectly, especially in people with risk factors, like obesity and hypertension. These people are already at risk for heart failure, especially heart failure with preserved ejection fraction, the most common type of heart failure today.”

Some health experts have warned that exercising might be dangerous for former COVID-19 patients who developed myocarditis. 

“We don’t want to see people at low risk stop exercising out of fear,” Khan said. “We’ve already seen the collateral damage of the pandemic leading to avoidance of hospitals for patients who may be experiencing heart attacks or strokes.”

Patients who had COVID-19 will need to be monitored long term for symptoms of heart failure, said first author Dr. Priya Mehta Freaney, cardiovascular disease fellow at Northwestern Medicine. “This is especially critical for those who experienced lung injury and may have cardiovascular complications related to chronic pulmonary disease following recovery from COVID-19,” she noted. 

“The pandemic emphasizes once again, the urgency with which we need to change how we are approaching overall health,” Khan said. “Before the pandemic even started, we have been seeing worsening trends with higher numbers of people, especially under age 65 years dying from heart failure. We are losing ground in the battle against heart failure, in large part, due to growing rates of obesity and diabetes and poor control of high blood pressure. And the disparities in heart failure are clear and have been amplified during COVID-19.”

Reference: Priya Mehta Freaney, Sanjiv J. Shah, Sadiya S. Khan et al., “COVID-19 and Heart Failure With Preserved Ejection Fraction”, JAMA. 2020;324(15):1499-1500. doi: 10.1001/jama.2020.17445

Provided by Northwestern University

Counting Patients’ Social Determinants of Health May Help Doctors Prevent Fatal Heart Attacks (Cardiology / Medicine)

Doctors may be able to predict their patients’ risks of fatal coronary heart disease more accurately by taking into account the number of adverse social factors affecting them, according to a new study led by researchers at Weill Cornell Medicine and NewYork-Presbyterian.

The researchers, whose findings appear Dec. 3 in Circulation, analyzed data from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study that tracked cardiovascular-related health outcomes in more than 20,000 people for a decade. The new analysis showed that participants who had more adverse social determinants of health, such as low income and educational attainment, were significantly more likely to die of coronary heart disease—mostly heart attacks—during the study. For example, people with three or more social determinants of health, on a list of seven, were about 67 percent more likely to have a fatal heart attack, even when accounting for differences in age and other health factors.

The researchers suggest that doctors consider using simple counts of these factors to better estimate their patients’ health risks and provide more aggressive treatment where applicable.

“Physicians tend to view social determinants of health as a peripheral part of clinical care management, but we think it should play a much more central role,” said lead author Dr. Monika Safford, John J. Kuiper Professor of Medicine at Weill Cornell Medicine and chief of the Division of General Internal Medicine at Weill Cornell Medicine and NewYork-Presbyterian/Weill Cornell Medical Center.

Social determinants of health have remained on the periphery of medicine, despite their potential for improving patient risk assessment, largely because no one has demonstrated an easy way to use them in day-to-day clinical practice.

“Physicians tend to be very busy people—they’re unlikely to adopt a complex tool for risk assessment,” Dr. Safford said. “Our approach therefore was to keep it simple.”

The analysis covered more than 22,000 people, who initially did not have diagnosed coronary heart disease, in the long-running REGARDS Study, on which Dr. Safford has been a lead investigator. The stroke-focused study has included ancillary studies of heart attacks and related health outcomes.

Dr. Safford and her colleagues identified a list of nine social determinants of health that prior research has linked individually to greater risks of heart attacks, strokes and related outcomes. They found that about half (48.8 percent) of those in the study group had two or more of these adverse social factors, and that having more of them generally predicted worse coronary heart disease outcomes during the study period. Participants with three or more social determinants were, for example, about three times more likely to suffer fatal coronary heart disease, compared to those with none of these factors.

These initial findings suggested that a count of social determinants of health could be a quick and easy source of information for doctors about their patients’ coronary heart disease risks—even if it is only predictive because the factors are linked to known cardiovascular risk factors such as hypertension and obesity. However, a further analysis suggested that a high count also contains an independent signal of fatal-coronary heart disease risk.

The researchers narrowed their social determinants of health list to the seven that were most strongly linked to fatal coronary heart disease: Black race, low education, low income, living in a zip code with high poverty, residence in one of the U.S. states with the least public health infrastructure, not seeing close friends/family in the past month, and lack of health insurance. They then adjusted the outcomes data based on differences in health factors, such as a greater burden of chronic disease in the high social determinants group. They still found that people with three or more social determinants had a 67 percent greater risk of fatal coronary heart disease.

A similar analysis found that people with two or more social determinants had a 14 percent greater risk of nonfatal heart attack, although that association was not statistically significant.

Noting a patient’s high number of social determinants of health could enable a cardiologist or general practitioner not only to anticipate a higher chance of bad outcomes, but also to mitigate that added risk with more intensive treatment, Dr. Safford said.

“Our group has also done studies on social determinants of health and the risks of stroke, diabetes, and heart failure, and we’ve had similar findings in every case, so we may be close to the point where counting social determinants of health is generally adopted into clinical practice,” she said.

Reference: Monika M. Safford, Evgeniya Reshetnyak,  Madeline R. Sterling, Joshua S. Richman, Paul M. Muntner, Raegan W. Durant, John Booth, Laura C. Pinheiro, “Number of Social Determinants of Health and Fatal and Nonfatal Incident Coronary Heart Disease in the REGARDS Study”, Circulation. 2021;143:244–253. https://doi.org/10.1161/CIRCULATIONAHA.120.048026 https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.120.048026

Provided by Weill Cornell Medicine

Brain Pressure Disorder that Causes Headache, Vision Problems on Rise (Psychiatry)

Increase Corresponds with Obesity Rates, Linked to Low Socioeconomic Status in Women

A new study has found a brain pressure disorder called idiopathic intracranial hypertension is on the rise, and the increase corresponds with rising obesity rates. The study is published in the January 20, 2021, online issue of Neurology®, the medical journal of the American Academy of Neurology. The study also found that for women, socioeconomic factors like income, education and housing may play a role in their risk.

Silhouette of man with left hand on forehead. Brain is outlined with red at the center © AAN

Idiopathic intracranial hypertension is when the pressure in the fluid surrounding the brain rises. It can mimic the symptoms of a brain tumor, causing chronic, disabling headaches, vision problems and in rare cases, vision loss. It is most often diagnosed in women of childbearing age. Treatment is often weight loss. In some cases, surgery may be required.

“The considerable increase in idiopathic intracranial hypertension we found may be due to many factors but likely mostly due to rising obesity rates,” said study author William Owen Pickrell, Ph.D., M.R.C.P., of Swansea University in Wales in the United Kingdom and a member of the American Academy of Neurology. “What is more surprising from our research is that women who experience poverty or other socioeconomic disadvantages may also have an increased risk independent of obesity.”

For the study, researchers used a national healthcare database in Wales to analyze 35 million patient years of data over a 15-year period, between 2003 and 2017. They identified 1,765 people with idiopathic intracranial hypertension during that time. Of the group, 85% were women. Researchers recorded body mass index measurements for study participants. Body mass index is calculated by dividing weight by height. For every one person with the disorder, researchers compared three people without it who were matched for gender, age and socioeconomic status.

The socioeconomic status of each person with the disorder was determined by where they live, using a national scoring system that considers factors like income, employment, health, education and access to services. People in the study were then divided into five groups ranging from those with the fewest socioeconomic advantages to those with the most.

Overall, researchers found a six-fold increase in the number of cases of the disorder over the course of the study. In 2003, for every 100,000 people, 12 were living with the disorder, compared to 76 people in 2017. Also, in 2013, for every 100,000 people, two were diagnosed during that year, compared to eight people in 2017.

Researchers found that the increasing number of people living with the disorder corresponded to rising obesity rates in Wales during the study, with 29% of the population being obese in 2003 compared to 40% in 2017.

“The worldwide prevalence of obesity nearly tripled between 1975 and 2016, so while our research looked specifically at people in Wales, our results may also have global relevance,” said Pickrell.

There were strong links for both men and women between body mass index and risk of the disorder. For women, there were 180 cases per 100,000 people during the study for those with high body mass index compared to 13 women with a body mass index considered to be ideal. For men, there were 21 cases per 100,000 among those with a high body mass index compared to eight cases for those with an ideal body mass index.

Researchers also found that for women only, socioeconomic factors were linked to risk. There were 452 women in the group with the fewest socioeconomic advantages compared to 197 in the group with the most. The women in the group with the fewest had a 1.5 times greater risk of developing the disorder than women in the group with the most, even after adjusting for body mass index.

“Of the five socioeconomic groups of our study participants, women in the lowest two groups made up more than half of the female participants in the study,” said Pickrell. “More research is needed to determine which socioeconomic factors such as diet, pollution, smoking or stress may play a role in increasing a woman’s risk of developing this disorder.”

A limitation of the study was that researchers identified the socioeconomic status of participants by the regions in which they lived instead of obtaining individual socioeconomic information for each participant.

Reference: Latif Miah, Huw Strafford, Beata Fonferko-Shadrach, Joe Hollinghurst, Inder MS Sawhney, Savvas Hadjikoutis, Mark I Rees, Rob Powell, Arron Lacey, W Owen Pickrell, “Incidence, Prevalence and Healthcare Outcomes in Idiopathic Intracranial Hypertension: A Population Study”, Neurology Jan 2021, DOI: 10.1212/WNL.0000000000011463 https://n.neurology.org/content/early/2021/01/20/WNL.0000000000011463

Provided by American Academy of Neurology

About American Academy of Neurology

The American Academy of Neurology is the world’s largest association of neurologists and neuroscience professionals, with 36,000 members. The AAN is dedicated to promoting the highest quality patient-centered neurologic care. A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as Alzheimer’s disease, stroke, migraine, multiple sclerosis, concussion, Parkinson’s disease and epilepsy.

For more information about the American Academy of Neurology, visit AAN.com or find us on FacebookTwitterLinkedInInstagram and YouTube.

Metformin Use Reduces Risk of Death for Patients With COVID-19 and Diabetes (Medicine)

Use of the diabetes drug metformin — before a diagnosis of COVID-19 — is associated with a threefold decrease in mortality in COVID-19 patients with Type 2 diabetes, according to a racially diverse study at the University of Alabama at Birmingham. Diabetes is a significant comorbidity for COVID-19.

Use of the diabetes drug metformin — before a diagnosis of COVID-19 — was associated with a threefold decrease in mortality in COVID-19 patients with Type 2 diabetes.

“This beneficial effect remained, even after correcting for age, sex, race, obesity, and hypertension or chronic kidney disease and heart failure,” said Anath Shalev, M.D., director of UAB’s Comprehensive Diabetes Center and leader of the study.

“Since similar results have now been obtained in different populations from around the world — including China, France and a UnitedHealthcare analysis — this suggests that the observed reduction in mortality risk associated with metformin use in subjects with Type 2 diabetes and COVID-19 might be generalizable,” Shalev said.

How metformin improves prognosis in the context of COVID-19 is not known, Shalev says. The UAB findings suggest that the mechanisms may go beyond any expected improvement in glycemic control or obesity, since neither body mass index, blood glucose nor hemoglobin A1C were lower in the metformin users who survived as compared to those who died.  

“The mechanisms may involve metformin’s previously described anti-inflammatory and anti-thrombotic effects,” Shalev said.

The study — first  made available in MedRxiv and now published in the peer-reviewed journal Frontiers in Endocrinology — included 25,326 patients tested for COVID-19 at the tertiary care UAB Hospital between Feb. 25 and June 22 of last year. Of the 604 patients found to be COVID-19-positive, 311 were African Americans. 

The primary outcome in the study was mortality in COVID-19-positive subjects, and the potential association with subject characteristics or comorbidities was analyzed.

Researchers found that Blacks, who are only 26 percent of Alabama’s population, were 52 percent of those who tested positive for COVID-19, and only 30 percent of those who tested negative. In contrast, only 36 percent of the COVID-19-positive subjects were white, while whites made up 56 percent of those who tested negative, further underlining the racial disparity. Once COVID-19-positive though, no significant racial difference in mortality was observed. 

“In our cohort,” Shalev said, “being African American appeared to be primarily a risk factor for contracting COVID-19, rather than for mortality. This suggests that any racial disparity observed is likely due to exposure risk and external socioeconomic factors, including access to proper health care.”

Overall mortality for COVID-19-positive patients was 11 percent. The study found that 93 percent of deaths occurred in subjects over the age of 50, and being male or having high blood pressure was associated with a significantly elevated risk of death. Diabetes was associated with a dramatic increase in mortality, with an odds ratio of 3.62. Overall, 67 percent of deaths in the study occurred in subjects with diabetes. 

The researchers looked at the effects of diabetes treatment on adverse COVID-19 outcomes, focusing on insulin and metformin as the two most common medications for Type 2 diabetes. They found that prior insulin use did not affect mortality risk.

However, prior metformin use was a different matter. Metformin use significantly reduced the odds of dying, and the 11 percent mortality for metformin users was not only comparable to that of the general COVID-19-positive population, it was dramatically lower than the 23 percent mortality for diabetes patients not on metformin.

After controlling for other covariates, age, sex and metformin use emerged as independent factors affecting COVID-19-related mortality. Interestingly, even after controlling for all these other covariates, death was significantly less likely — with an odds ratio of 0.33 — for Type 2 diabetes subjects taking metformin, compared with those who did not take metformin.

Anath Shalev, M.D. © UAB

“These results suggest that, while diabetes is an independent risk factor for COVID-19-related mortality,” Shalev said, “this risk is dramatically reduced in subjects taking metformin — raising the possibility that metformin may provide a protective approach in this high-risk population.” 

The researchers say future studies will need to explore how metformin is protective, as well as assess the risks and benefits of metformin treatment and the indications for its use in the face of the ongoing COVID-19 pandemic. 

This study is part of a new Precision Diabetes Program, a collaboration between the UAB Comprehensive Diabetes Center and the Hugh Kaul Precision Medicine Institute at UAB. 

Co-authors with Shalev for the paper, “Metformin use is associated with reduced mortality in a diverse population with COVID-19 and diabetes,” are Andrew B. Crouse and Matthew Might, the Hugh Kaul Precision Medicine Institute at UAB; Tiffany Grimes and Fernando Ovalle, the Comprehensive Diabetes Center and the Department of Medicine Division of Endocrinology, Diabetes and Metabolism at UAB; and Peng Li, UAB School of Nursing

Support came from National Institutes of Health grants DK078752, DK120379 and TR001417.

Shalev is a professor in the UAB Department of Medicine Division of Endocrinology, Diabetes and Metabolism, and she holds the Nancy R. and Eugene C. Gwaltney Family Endowed Chair in Juvenile Diabetes Research.

Reference: Andrew Crouse, Tiffany Grimes, Peng Li, Matthew Might et al., “Metformin Use Is Associated With Reduced Mortality in a Diverse Population With COVID-19 and Diabetes”, Front. Endocrinol., 13 January 2021 | https://doi.org/10.3389/fendo.2020.600439 https://www.frontiersin.org/articles/10.3389/fendo.2020.600439/full?&utm_source=Email_to_authors_&utm_medium=Email&utm_content=T1_11.5e1_author&utm_campaign=Email_publication&field=&journalName=Frontiers_in_Endocrinology&id=600439

Provided by University of Alabama at Birmingham

Difference in Blood Pressure Between Arms Linked to Greater Death Risk (Medicine)

Robust evidence from a large international study confirms that a difference in blood pressure readings between arms is linked to greater risk of heart attack, stroke and death.

Led by the University of Exeter, the global INTERPRESS-IPD Collaboration conducted a meta-analysis of all the available research, then merged data from 24 global studies to create a database of nearly 54,000 people. The data spanned adults from Europe, the US, Africa and Asia for whom blood pressure readings for both arms were available.

Funded by the National Institute for Health Research (NIHR) and published today in Hypertension, the study is the first to conclude that the greater the inter-arm blood pressure difference, the greater the patient’s additional health risk.

Currently, international blood pressure guidelines advise health professionals to measure blood pressure in both arms when assessing cardiovascular risk,- yet this is widely ignored. The new study provides a new upper limit of ‘normal’ for an inter-arm difference in blood pressure, which is significantly lower than the current guidance. The research could lead to a change in international hypertension guidelines, meaning more at-risk patients could be identified and receive potentially life-saving treatment.

In a methodology that put patients at its heart, working with a patient advisory group at every step of the research, the team analysed data on inter-arm blood pressure difference, and tracked the number of deaths, heart attacks and strokes that occurred in the cohort over 10 years.

Lead author and GP Dr. Chris Clark, of the University of Exeter Medical School, said: “Checking one arm then the other with a routinely used blood pressure monitor is cheap and can be carried out in any healthcare setting, without the need for additional or expensive equipment. Whilst international guidelines currently recommend that this is done, it only happens around half of the time at best, usually due to time constraints. Our research shows that the little extra time it takes to measure both arms could ultimately save lives”.

“We’ve long known that a difference in blood pressure between the two arms is linked to poorer health outcomes. The large numbers involved in the INTERPRESS-IPD study help us to understand this in more detail. It tells us that the higher the difference in blood pressure between arms, the greater the cardiovascular risk, so it really is critical to measure both arms to establish which patients may be at significantly increased risk. Patients who require a blood pressure check should now expect that it’s checked in both arms, at least once.”

Blood pressure rises and falls in a cycle with each pulse. It is measured in units of millimetres of mercury (mmHg), and the reading is always given as two numbers: the upper (systolic) reading represents the maximum blood pressure and the lower (diastolic) value is the minimum blood pressure. A high systolic blood pressure indicates hypertension. This affects one third of the adult population and is the single leading cause globally of preventable heart attacks, strokes and deaths. A significant difference between the systolic blood pressure measurements in the two arms could be indicative of a narrowing, or a stiffening, of the arteries, which can affect blood flow. These arterial changes are recognised as a further risk marker for subsequent heart attack, stroke or early death, and should be investigated for treatment.

The researchers concluded that each mmHg difference found between the two arms, elevated predicted 10-year risk of one of the following occurring by one percent; new angina, a heart attack or stroke.

At the moment, both UK and European guidelines recognise a systolic difference of 15 mmHg or more between the two arms as the threshold indicative of additional cardiovascular risk. This new study found that a lower threshold of 10 mmHg was clearly indicative of additional risk, which would mean that far more people should be considered for treatment if such a difference between arms is present. To this end, the research team has created a tool that is easy for clinicians to use, to establish who should be considered for treatment based on their risk, incorporating the blood pressure reading in both arms.

Research co-author Professor Victor Aboyans, head of the department of cardiology at the Dupuytren University Hospital in Limoges, France, said “We believe that a 10 mmHg difference can now reasonably be regarded as an upper limit of normal for systolic inter-arm blood pressure, when both arms are measured in sequence during routine clinical appointments. This information should be incorporated into future guidelines and clinical practice in assessing cardiovascular risk. It would mean many more people were considered for treatment that could reduce their risk of heart attack, stroke and death.”

An interarm difference of greater than 10 mmHg occurs in 11 percent of people with high blood pressure (hypertension) – itself a known health risk—and in four percent of the general population.

References: Christopher E. Clark, Fiona C. Warren, Kate Boddy, Sinead T.J. McDonagh, Sarah F. Moore, John Goddard, Nigel Reed, Malcolm Turner, Maria Teresa Alzamora, Rafel Ramos Blanes, Shao-Yuan Chuang, Michael Criqui, Marie Dahl, Gunnar Engström, Raimund Erbel, Mark Espeland, Luigi Ferrucci, Maëlenn Guerchet, Andrew Hattersley, Carlos Lahoz, Robyn L. McClelland, Mary M. McDermott, Jackie Price, Henri E. Stoffers, Ji-Guang Wang, Jan Westerink, James White, Lyne Cloutier, Rod S. Taylor, Angela C. Shore, Richard J. McManus, Victor Aboyans, John L. Campbell, “Associations Between Systolic Interarm Differences in Blood Pressure and Cardiovascular Disease Outcomes and Mortality– Individual Participant Data Meta-Analysis, Development and Validation of a Prognostic Algorithm: The INTERPRESS-IPD Collaboration”, Hypertension, 2020. https://www.ahajournals.org/doi/10.1161/HYPERTENSIONAHA.120.15997

Provided by University of Exeter