Category Archives: Studies

Covid-19 Studies: 77% Of Hospitalized Patients Are Overweight Or Obese

SEPTEMBER 11, 2020

But on its own, “BMI [body mass index] remains a strong independent risk factor” for severe COVID-19, according to several studies that adjusted for age, sex, social class, diabetes, and heart conditions, says Naveed Sattar, an expert in cardiometabolic disease at the University of Glasgow. “And it seems to be a linear line, straight up.”

  • For starters, the blood of people with obesity has an increased tendency to clot—an especially grave risk during an infection that, when severe, independently peppers the small vessels of the lungs with clots 
  • Immunity also weakens in people with obesity, in part because fat cells infiltrate the organs where immune cells are produced and stored, such as the spleen, bone marrow, and thymus, says Catherine Andersen, a nutritional scientist at Fairfield University. “We are losing immune tissue in exchange for adipose tissue, making the immune system less effective in either protecting the body from pathogens or responding to a vaccine,” she says.

The impact extends to the 32% of people in the United States who are overweight. The largest descriptive study yet of hospitalized U.S. COVID-19 patients, posted as a preprint last month by Genentech researchers, found that 77% of nearly 17,000 patients hospitalized with COVID-19 were overweight (29%) or obese (48%). (The Centers for Disease Control and Prevention defines overweight as having a BMI of 25 to 29.9 kilograms per square meter, and obesity as a BMI of 30 or greater.)

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Studies: “Insomnia / Short Sleep Duration” Is A Type 2 Diabetes “Risk Factor”

Diabetologia  (Sept 8, 2020) – Insomnia with objective short sleep duration has been associated with an increased risk of type 2 diabetes in observational studies [2728]. The present MR study found strong and suggestive evidence of a causal association of insomnia and short sleep duration, respectively, with increased risk of type 2 diabetes.

Conclusions/interpretation

The present study verified several previously reported risk factors and identified novel potential risk factors for type 2 diabetes. Prevention strategies for type 2 diabetes should be considered from multiple perspectives on obesity, mental health, sleep quality, education level, birthweight and smoking.

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Stanford: Researchers Find Way To “Regrow” New Cartilage In Joints

The Stanford researchers figured out how to regrow articular cartilage by first causing slight injury to the joint tissue, then using chemical signals to steer the growth of skeletal stem cells as the injuries heal. The work was published Aug. 17 in the journal Nature Medicine.

“Cartilage has practically zero regenerative potential in adulthood, so once it’s injured or gone, what we can do for patients has been very limited,” said assistant professor of surgery Charles K.F. Chan, PhD. “It’s extremely gratifying to find a way to help the body regrow this important tissue.”

STANFORD MEDICINE (Aug 17, 2020): Researchers at the Stanford University School of Medicine have discovered a way to regenerate, in mice and human tissue, the cushion of cartilage found in joints.

Loss of this slippery and shock-absorbing tissue layer, called articular cartilage, is responsible for many cases of joint pain and arthritis, which afflicts more than 55 million Americans. Nearly 1 in 4 adult Americans suffer from arthritis, and far more are burdened by joint pain and inflammation generally.

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Top New Books On Aging: “Exercised” By Daniel E. Lieberman – “Extending Longevity” (Harvard)

HARVARD MAGAZINE (SEPT – OCT 2020): From the book EXERCISED: Why Something We Never Evolved to Do Is Healthy and Rewarding by Daniel E. Lieberman, to be published on September 8, 2020 by Pantheon Books:

‘….many of the mechanisms that slow aging and extend life are turned on by physical activity, especially as we get older. Human health and longevity are thus extended both by and for physical activity.’

What Happens When We Exercise?
The graph breaks total energy expenditure (TEE) into two parts: active energy expenditure, and resting metabolism. Resting metabolism remains elevated for hours even after exercise ceases, burning additional calories in a phase known as excess post-exercise oxygen consumption (EPOC).

Exercise is like scrubbing the kitchen floor so well after a spill that the whole floor ends up being cleaner. The modest stresses caused by exercise trigger a reparative response yielding a general benefit.

In order to elucidate the links between exercise and aging, I propose a corollary to the Grandmother Hypothesis, which I call the Active Grandparent Hypothesis. According to this idea, human longevity was not only selected for but was also made possible by having to work hard during old age to help as many children, grandchildren, and other younger relatives as possible survive and thrive. That is, while there may have been selection for genes (as yet unidentified) that help humans live past the age of 50, there was also selection for genes that repair and maintain our bodies when we are physically active.

Daniel E. Lieberman is a paleoanthropologist at Harvard University, where he is the Edwin M Lerner II Professor of Biological Sciences, and Professor in the Department of Human Evolutionary Biology. He is best known for his research on the evolution of the human head and the evolution of the human body.

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Health: “Compression Therapy” Reduces Chronic Cellulitis & Leg Edema

New England Journal of Medicine (Aug 13, 2020) – In this small, single-center, nonblinded trial involving patients with chronic edema of the leg and cellulitis, compression therapy resulted in a lower incidence of recurrence of cellulitis than conservative treatment.

The researchers have conducted a single-center, randomized, nonblinded trial that aimed to find out an association between the compression therapy and controlled incidents of chronic edema of the leg and people with cellulitis that can be defined as an infection of the skin that involves subcutaneous tissues or the innermost layer of the skin. Cellulitis can be caused by trauma or scratching of other lesions due to animal or human bites that result in fever, extreme pain, and redness of the skin.

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Brain Research: 40% Of Dementia Cases Prevented With Lifestyle Changes

Dementia Risk Reduced by Lifestyle factors - USC Keck Medicine Infographic

“We are learning that tactics to avoid dementia begin early and continue throughout life, so it’s never too early or too late to take action,” says commission member and AAIC presenter Lon Schneider, MD, co-director of the USC Alzheimer Disease Research Center‘s clinical core and professor of psychiatry and the behavioral sciences and neurology at the Keck School of Medicine of USC.

LOS ANGELES — Modifying 12 risk factors over a lifetime could delay or prevent 40% of dementia cases, according to an updated report by the Lancet Commission on dementia prevention, intervention and care presented at the Alzheimer’s Association International Conference (AAIC 2020).

Twenty-eight world-leading dementia experts added three new risk factors in the new report — excessive alcohol intake and head injury in mid-life and air pollution in later life. These are in addition to nine factors previously identified by the commission in 2017: less education early in life; mid-life hearing loss, hypertension and obesity; and smoking, depression, social isolation, physical inactivity and diabetes later in life (65 and up).

Schneider and commission members recommend that policymakers and individuals adopt the following interventions:

  • Aim to maintain systolic blood pressure of 130 mm Hg or less from the age of 40.
  • Encourage use of hearing aids for hearing loss and reduce hearing loss by protecting ears from high noise levels.
  • Reduce exposure to air pollution and second-hand tobacco smoke.
  • Prevent head injury (particularly by targeting high-risk occupations).
  • Limit alcohol intake to no more than 21 units per week (one unit of alcohol equals 10 ml or 8 g pure alcohol).
  • Stop smoking and support others to stop smoking.
  • Provide all children with primary and secondary education.
  • Lead an active life into mid-life and possibly later life.
  • Reduce obesity and the linked condition of diabetes.

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Health: New Studies Find “Coffee & Caffeine” Lower Heart Disease, Cancer Risk

NEW ENGLAND JOURNAL OF MEDICINE (JULY 23, 2020): A large body of evidence suggests that consumption of caffeinated coffee, the main source of caffeine intake in adults in the United States, does not increase the risk of cardiovascular diseases and cancers. In fact, consumption of 3 to 5 standard cups of coffee daily has been consistently associated with a reduced risk of several chronic diseases. 

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The New England Journal of Medicine LogoCoffee and tea have been consumed for hundreds of years and have become an important part of cultural traditions and social life.5 In addition, people use coffee beverages to increase wakefulness and work productivity. The caffeine content of commonly used sources of caffeine is shown in Table 1. For a typical serving, the caffeine content is highest in coffee, energy drinks, and caffeine tablets; intermediate in tea; and lowest in soft drinks. In the United States, 85% of adults consume caffeine daily,6 and average caffeine intake is 135 mg per day, which is equivalent to about 1.5 standard cups of coffee (with a standard cup defined as 8 fluid oz [235 ml]).7 Coffee is the predominant source of caffeine ingested by adults, whereas soft drinks and tea are more important sources of caffeine ingested by adolescents,

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Studies: 4- And 6-Hour Time-Restricted Eating (TRE) Diets, No Food Limits Result In Weight Loss

UIC Chicago Illinois
University of Illinois, Chicago (July 15, 2020)

“The findings of this study are promising and reinforce what we’ve seen in other studies — fasting diets are a viable option for people who want to lose weight, especially for people who do not want to count calories or find other diets to be fatiguing,” Varady said. 

…participants in both daily fasting groups reduced calorie intake by about 550 calories each day simply by adhering to the schedule and lost about 3% of their body weight. The researchers also found that insulin resistance and oxidative stress levels were reduced among participants in the study groups when compared with the control group.

4- And 6-Hour Time Restricted Eating TRE DietsTwo daily fasting diets, also known as time-restricted feeding diets, are effective for weight loss, according to a new study published by researchers from the University of Illinois at Chicago.

The study reported results from a clinical trial that compared a 4-hour time-restricted feeding diet and a 6-hour time-restricted feeding diet to a control group.

“This is the first human clinical trial to compare the effects of two popular forms of time-restricted feeding on body weight and cardiometabolic risk factors,” said Krista Varady, professor of nutrition at the UIC College of Applied Health Sciences and corresponding author of the story.

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Cognition & Brain Studies: Apathy, Not Depression, Associated With Dementia

‘Journal of Neurology, Neurosurgery & Psychiatry” (July 10, 2020):

jnnp-2020-July-91-7-677-F1.mediumWe tested the hypothesis that apathy, but not depression, is associated with dementia in patients with SVD. We found that higher baseline apathy, as well as increasing apathy over time, were associated with an increased dementia risk. In contrast, neither baseline depression or change in depression was associated with dementia. The relationship between apathy and dementia remained after controlling for other well-established risk factors including age, education and cognition. Finally, adding apathy to models predicting dementia improved model fit. These results suggest that apathy may be a prodromal symptom of dementia in patients with SVD.

Cerebral small vessel disease (SVD) is the leading vascular cause of dementia and plays a major role in cognitive decline and mortality.1 2 SVD affects the small vessels of the brain, leading to damage in the subcortical grey and white matter.1 The resulting clinical presentation includes cognitive and neuropsychiatric symptoms.1

Apathy is a reduction in goal-directed behaviour, which is a common neuropsychiatric symptom in SVD.3 Importantly, apathy is dissociable from depression,3 4 another symptom in SVD for which low mood is a predominant manifestation.5 Although there is some symptomatic overlap between the two,6 research using diffusion imaging reported that apathy, but not depression, was associated with white matter network damage in SVD.3 Many of the white matter pathways underlying apathy overlap with those related to cognitive impairment, and accordingly apathy, rather than depression, has been associated with cognitive deficits in SVD.7 These results suggest that apathy and cognitive impairment are symptomatic of prodromal dementia in SVD.

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Health Studies: Declining “REM Sleep” Linked To Increasing Death Rates

From U.S. News (July 7, 2020):

“Numerous studies have linked insufficient sleep with significant health consequences. Yet, many people ignore the signs of sleep problems or don’t allow enough time to get adequate sleep,” said lead researcher Eileen Leary. She is a senior manager of clinical research at Stanford University in Palo Alto, Calif.

Jama Neurology

“REM sleep appears to be a reliable predictor of mortality and may have other predictive health values,” Leary said. “Strategies to preserve REM may influence clinical therapies and reduce mortality risk, particularly for adults with less than 15% of REM sleep.”

REM (rapid eye movement) sleep is when dreams occur and the body repairs itself from the ravages of the day. For every 5% reduction in REM sleep, mortality rates increase 13% to 17% among older and middle-aged adults, researchers report.

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For the study, Leary and her colleagues included more than 2,600 men, average age 76, who were followed for a median of 12 years. They also collected data on nearly 1,400 men and women, average age 52, who were part of another study and were followed for a median of 21 years.

Poor REM sleep was tied to early death from any cause as well as death from cardiovascular and other diseases, the researchers found.

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