Tag: 2/5/23

People Near Airports Likely to Suffer from Shorter Sleep

Photo by Daniel Eledut on Unsplash

A new study published in the journal Environmental Health Perspectives has found that people who were exposed to even moderate levels of aircraft noise were less likely to receive the minimum recommended amount of sleep each night, and this risk increased among people living near a major cargo airport, or near a large water body, and among people with no hearing loss.

A new analysis by Boston University School of Public Health (BUSPH) and Oregon State University has found that exposure to even moderate levels of airplane noise may disrupt sleep, building upon a growing body of research on the adverse health effects of environmental noise.

The study found that people who were exposed to airplane noise at levels as low as 45dB were more likely to sleep less than 7 hours per night. For comparison, the sound of a whisper is 30dB, a library setting is 40dB, and a typical conversation at home is 50dB.

Sleep is essential to overall health and well-being, including daily physical and mental functioning, and a lack of adequate sleep can lead to increased risks of cardiovascular disease, depression, diabetes, cancer, and numerous other health conditions. Health experts state that most adults need seven to nine hours of sleep each night for healthy functioning.

This study is the first large-scale analysis of aircraft noise and sleep duration that accounts for the disruptive effects of multiple environmental exposures in communities, such as greenery and light at night (LAN).

Despite how common exposure to noise from aircraft is for many people, little is known about the health effects of aircraft noise, particularly in the U.S., according to study lead author Matthew Bozigar, assistant professor of epidemiology at OSU, and study senior author Junenette Peters, associate professor of environmental health at BUSPH.

“This study helps us understand the potential health pathways by which aircraft noise may act, such as through disrupted sleep,” Peters says.

For the study, Dr. Peters, Dr. Bozigar and colleagues from BUSPH, Brigham and Women’s Hospital, Harvard Medical School, and Harvard T.H. Chan School of Public Health examined airplane noise exposure and self-reported sleep disturbance among more than 35 000 participants living around 90 of the major US airports. The participants were selected from the Nurses’ Health Study (NHS), an ongoing, prospective study of US female nurses who have completed biennial questionnaires since 1976.

The team examined aircraft noise levels every five years from 1995 to 2015, focusing on two measurements: a nighttime estimate (Lnight) that captures airplane noise occurring when people sleep, and a day-night estimate (DNL) that captures the average noise level over a 24-hour period and applies a 10 dB adjustment for aircraft noise occurring at night, when background noise is low. The DNL is also the primary metric that the FAA uses for aircraft noise policies, and the threshold for significant noise impacts is above DNL 65 dB. The team linked these measures at multiple thresholds with the nurses’ geocoded residential addresses.

After accounting for a range of factors, including demographics, health behaviors, comorbidities, and environmental exposures such as greenery and light at night (LAN), the results showed that the odds of sleeping less than seven hours rose as airplane noise exposure increased.

Short sleep duration was also more likely among nurses who lived on the West Coast, near a major cargo airport or a large body of water, as well as among nurses who reported no hearing loss.

“We found surprisingly strong relationships for particular subgroups that we are still trying to understand,” Bozigar says. “For instance, there was a relatively strong signal between aircraft noise and both dimensions of disrupted sleep, short sleep duration and poor sleep quality, near major cargo airports. There is likely more going on to this story, as cargo operations tend to use larger, older, heavily laden, and therefore noisier aircraft that often fly through the nighttime hours. And the quantity of cargo shipped by air has been steadily increasing over the last couple of decades, possibly linked to more e-commerce. If the trends continue, it could mean more aircraft noise impacts to more groups of people.”

While the results suggested a clear link between airplane noise and sleep duration, the researchers observed no consistent association between aircraft noise and quality of sleep.

Source: Boston University School of Public Health

How Psychedelics Alter Brain Activity to Produce ‘Trips’

In a study published in the journal PNAS, detailed brain imaging data from 20 healthy volunteers revealed how the potent psychedelic compound, DMT (dimethyltryptamine), alters brain function. During the immersive DMT experience, there was increased connectivity across the brain, with more communication between different areas and systems. The changes to brain activity were most prominent in areas linked with ‘higher level’ functions, such as imagination.

DMT is a potent psychedelic found naturally in certain plants and animals, and unlike classic psychedelics, such as LSD or psilocybin, DMT’s has shorter-lasting effects on the brain, measured in minutes, rather than hours. It occurs in trace amounts in the human body and is the major psychoactive compound in ayahuasca.

The study is the first to track brain activity before, during and after the DMT experience in such detail.

Dr Chris Timmerman, from the Centre for Psychedelic Research at Imperial College London, and first author on the study, said: “This work is exciting as it provides the most advanced human neuroimaging view of the psychedelic state to-date.

“One increasingly popular view is that much of brain function is concerned with modelling or predicting its environment. Humans have unusually big brains and model an unusually large amount of the world. For example, like with optical illusions, when we’re looking at something, some of what we’re actually seeing is our brain filling in the blanks based on what we already know. What we have seen with DMT is that activity in highly evolved areas and systems of the brain that encode especially high-level models becomes highly dysregulated under the drug, and this relates to the intense drug ‘trip’.”

DMT can produce intense and immersive altered states of consciousness, with the experience characterised by vivid and bizarre visions, a sense of ‘visiting’ alternative realities or dimensions, and similarities with near death experiences. But exactly how the compound alters brain function to account for such effects has been unclear.

In the latest study, 20 healthy volunteers were given an injection of the drug while researchers from Imperial’s Centre for Psychedelic Research captured detailed imagery of their brains, enabling the team to study how activity changes before, during and after the trip.

Volunteers intravenously received a high dose of DMT (20mg), while simultaneously undergoing functional magnetic resonance imaging (fMRI) of their brain and electroencephalography (EEG). The total psychedelic experience lasted about 20 minutes, and at regular intervals, volunteers provided a rating of the subjective intensity of their experience (on a 1 to 10 scale).

The fMRI scans found changes to activity within and between brain regions in volunteers under the influence of DMT. Effects included increased connectivity across the brain, with more communication between different areas and systems. These phenomena, termed ‘network disintegration and desegregation’ and increased ‘global functional connectivity’, align with previous studies with other psychedelics. The changes to activity were most prominent in brain areas linked with ‘higher level’, human-specific functions, such as imagination.

The researchers highlight that while their study is not the first to image the brain under the influence of psychedelics or the first to show the signatures of brain activity linked to psychedelics, it is the first to combine imaging techniques to study the brain during a highly immersive psychedelic experience. They explain the work provides further evidence of how DMT, and psychedelics more generally, exert their effects by disrupting high level brain systems.

Prof Robin Carhart-Harris, founder of the Centre for Psychedelic Research at Imperial College London, and senior author on the paper (now working at the University of California, San Francisco), commented: “Motivated by, and building on our previous research with psychedelics, the present work combined two complementary methods for imaging the brain imaging. fMRI allowed us to see the whole of the brain, including its deepest structures, and EEG helped us view the brain’s fine-grained rhythmic activity.

“Our results revealed that when a volunteer was on DMT there was a marked dysregulation of some of the brain rhythms that would ordinarily be dominant. The brain switched in its mode of functioning to something altogether more anarchic. It will be fascinating to follow-up on these insights in the years to come. Psychedelics are proving to be extremely powerful scientific tools for furthering our understanding of how brain activity relates to conscious experience.”

The Imperial team is now exploring how to prolong the peak of the psychedelic experience through continuous infusion with DMT, and some are also advising on a commercially run trial to assess DMT for patients with depression.

Source: Imperial College London

Vitamin D may be Necessary for Effective Immunotherapy in Skin Cancer

3D structure of a melanoma cell derived by ion abrasion scanning electron microscopy. Credit: Sriram Subramaniam/ National Cancer Institute

Vitamin D has many effects on the body, including regulation of the immune system. New research indicates that for patients with advanced skin cancer, it may be important to maintain normal vitamin D levels when receiving immunotherapy in the form of immune checkpoint inhibitors. The findings are published in CANCER.

To see whether levels of vitamin D might impact the effectiveness of immune checkpoint inhibitors, investigators analysed the blood of 200 patients with advanced melanoma both before and every 12 weeks during immunotherapy treatment.

A favourable response rate to immune checkpoint inhibitors was observed in 56.0% of patients in the group with normal baseline vitamin D levels or normal levels obtained with vitamin D supplementation, compared with 36.2% in the group with low vitamin D levels without supplementation. Progression‐free survival in these groups was 11.25 and 5.75 months, respectively.

“Of course, vitamin D is not itself an anti-cancer drug, but its normal serum level is needed for the proper functioning of the immune system, including the response that anti-cancer drugs like immune checkpoint inhibitors affect,” said lead author Łukasz Galus, MD, of Poznan University of Medical Sciences, in Poland. “In our opinion, after appropriately randomised confirmation of our results, the assessment of vitamin D levels and its supplementation could be considered in the management of melanoma.”

Source: Wiley

Food Shortages at Chris Hani Baragwanath as Suppliers Fail to Deliver

Chris Hani Baragwanath Academic Hospital (CHBAH) has been hit with shortages of essential foods as contractors fail to deliver the quantities of food tendered for, Daily Maverick reports.

Last week, a head of department at CHBAH notified Daily Maverick of the developing crisis, saying “So once again there is a food crises at Bara – suppliers weren’t paid, also no soap and hand towels and as a result infections spreading 😡.”

The unnamed healthcare worker said that the crisis was due to small suppliers being unable to fulfil the quantities for tenders they secured. Dry goods were particularly affected, and protein substitutes were having to be purchased from petty cash which was now depleted. This was verified by another healthcare worker, who described a situation of hospital kitchens having to borrow from one another.

This comes after new details into Gauteng health department tender corruption have emerged thanks to a whistleblower.

One doctor spoke of elective surgeries being cancelled due to financial pressure, and an atmosphere of intimidation. Motalatale Modiba, spokesperson for the Gauteng Department of Health, denied that there was a food shortage situation, but said that delivery of some protein food items, such as chicken and fish, had been withheld due to administrative payment delays.

Read the full story at Daily Maverick.

Preterm Birth and Size Linked to Adult Fibrillation Risk

Photo by Hush Naidoo on Unsplash

A new study published in JAMA Pediatrics showed an association between being born preterm or large for gestational age and increased risks of atrial fibrillation later in life. Being small for gestational age at birth was only associated with an increased risk of atrial fibrillation up to the age of 18.

The incidence of atrial fibrillation in the young has increased over the past few decades, from low levels.

To date there have been little or mixed findings regarding the risk of atrial fibrillation in those with adverse birth outcomes. Atrial fibrillation increases the risk of stroke and other cardiovascular conditions, and is the most common form of cardiac arrhythmia. It mainly affects the middle-aged and the elderly. The estimated incidence in the young is low, 0.12 to 0.16%.

Low incidence in the young

A collaborative study involving researchers from Karolinska Institutet has now investigated the risk of atrial fibrillation according to preterm birth and foetal growth.

“Atrial fibrillation at a young age may involve a heavy socioeconomic burden for the affected individuals and we need to learn more about the underlying causes of the disease,” says first author Fen Yang, doctoral student at Karolinska Institutet. “Our findings may highlight the need to monitor and prevent the disease in individuals with an elevated risk of atrial fibrillation.”

“We found that individuals born preterm and those who were large for gestational age at birth had a slightly higher risk of developing atrial fibrillation up to middle-age than those with corresponding normal birth outcomes,” says principal investigator Krisztina László, associate professor at the Department of Global Public Health, Karolinska Institutet, and senior lecturer at the Department of Public Health and Caring Sciences at Uppsala University. “Individuals who were small for gestational age at birth had an increased risk of atrial fibrillation up to the age of 18, but not later in adulthood.”

The risk increase was 30% for individuals born preterm, 55% for individuals who were large at birth and 71% for individuals who were both preterm and large for gestational age at birth.

Eight million participants

The results of the study are based on statistical analyses of over eight million births from Danish (1978–2016), Finnish (1987–2014) and Swedish (1973–2014) medical birth registries who were followed for incident atrial fibrillation in the national patient and cause of death registries up to 2021. The results were compared with siblings in the same families. Since the study was observational, no causal relationships could be ascertained.

The researchers say that future studies may investigate the association between preterm birth, foetal growth, and the risk of atrial fibrillation up to old age.

Source: Karolinska Institutet