Year: 2023

Social Isolation Linked to Reduced Brain Volume in Older People

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A study of nearly 9000 older people in Japan found that those who have little social contact with others may be more likely to have reduction of overall brain volume, and in areas of the brain affected by dementia, compared with those who have more frequent social contact. The study results were published in Neurology.

“Social isolation is a growing problem for older adults,” said study author Toshiharu Ninomiya, MD, PhD, of Kyushu University in Fukuoka, Japan. “These results suggest that providing support for people to help them start and maintain their connections to others may be beneficial for preventing brain atrophy and the development of dementia.”

The study involved 8896 people without dementia, average age 73. They had MRI brain scans and health exams, and were asked how often they were in contact with friends or relatives that did not live with them.

The people with the lowest amount of social contact had overall brain volume that was significantly lower than those with the most social contact. The total brain volume, or the sum of white and grey matter, as a percentage of the total intracranial volume, or the volume within the cranium, including the brain, meninges, and cerebrospinal fluid, was 67.3% in the lowest contact group compared to 67.8% in the highest contact group. They also had lower volumes in areas of the brain such as the hippocampus and amygdala that play a role in memory and are affected by dementia.

The researchers took into account other factors that could affect brain volume, such as age, diabetes, smoking and exercise.

The socially isolated people also had more small areas of damage in the brain, called white matter lesions, than the people with frequent social contact. The percentage of intracranial volume made up of white matter lesions was 0.30 for the socially isolated group, compared to 0.26 for the most socially connected group.

The researchers found that symptoms of depression partly explained the relationship between social isolation and brain volumes. However, symptoms of depression accounted for only 15% to 29% of the association.

“While this study is a snapshot in time and does not determine that social isolation causes brain atrophy, some studies have shown that exposing older people to socially stimulating groups stopped or even reversed declines in brain volume and improved thinking and memory skills, so it’s possible that interventions to improve people’s social isolation could prevent brain volume loss and the dementia that often follows,” Ninomiya said.

Since the study involved only older Japanese people, a limitation is that the findings may not be generalisable to people of other ethnicities and younger people.

Source: American Academy of Neurology

Does Low Bone Density Predict an Increased Risk of Dementia?

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People who have low bone density may have an increased risk of developing dementia compared to people who have higher bone density, according to a study of over 3500 people published in Neurology. As an observational study, it only shows an association and cannot prove that low bone density causes dementia.

“Low bone density and dementia are two conditions that commonly affect older people simultaneously, especially as bone loss often increases due to physical inactivity and poor nutrition during dementia,” said study author Mohammad Arfan Ikram, MD, PhD, of the Erasmus University Medical Center in Rotterdam, Netherlands. “However, little is known about bone loss that occurs in the period leading up to dementia. Our study found that bone loss indeed already occurs before dementia and thus is linked to a higher risk of dementia.”

The study involved 3651 people in the Netherlands with an average age of 72 who did not have dementia at the start of the study. Over an average of 11 years of follow-up, 688 people or 19% developed dementia.

X-rays were used to identify bone density, and participants were interviewed every four to five years and completed physical tests such as bone scans and tests for dementia.

Of the 1211 people with the lowest total body bone density, 90 people developed dementia within 10 years, compared to 57 of the 1211 people with the highest bone density.

After adjusting for factors such as age, sex, education, other illnesses and medication use, and a family history of dementia, researchers found that within 10 years, people with the lowest total body bone density were 42% more likely to develop dementia than people in the highest group.

“Previous research has found factors like diet and exercise may impact bones differently as well as the risk of dementia,” Ikram added. “Our research has found a link between bone loss and dementia, but further studies are needed to better understand this connection between bone density and memory loss. It’s possible that bone loss may occur already in the earliest phases of dementia, years before any clinical symptoms manifest themselves. If that were the case, bone loss could be an indicator of risk for dementia and people with bone loss could be targeted for screening and improved care.”

A limitation of the study is that participants were primarily of European origin and age 70 or older at the start of the study, so these findings may vary in different races, ethnicities, and younger age groups.

Source: American Academy of Neurology

Scientists Abuzz over a Genetic Way to Deafen Mosquitoes

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Specific receptors in the ears of mosquitoes have been revealed to modulate their hearing, finds a new study led by researchers at UCL and University of Oldenburg. Since male mosquitoes need to hear female mosquitoes is a crucial factor in their reproduction, this discovery could help develop new insecticides and control the spread of harmful diseases, such as malaria, dengue, and yellow fever.

In the study, published in Nature Communications, the researchers focused on a signalling pathway involving a molecule called octopamine. They demonstrated that it is key for mosquito hearing and mating partner detection, and so is a potential new target for mosquito control.

Male mosquitoes acoustically detect the buzz generated by females within large swarms that form transiently at dusk.

As swarms are potentially noisy, mosquitoes have developed highly sophisticated ears to detect the faint flight tone of females amid hundreds of mosquitoes flying together.

However, the molecular mechanisms by which mosquito males ‘sharpen their ears’ to respond to female flight tones during swarm time have been largely unknown.

The researchers looked at the expression of genes in the mosquito ear and found that an octopamine receptor specifically peaks in the male mosquito ear when mosquitoes swarm.

The study found that octopamine affects mosquito hearing on multiple levels. It modulates the frequency tuning and stiffness of the sound receiver in the male ear, and also controls other mechanical changes to boost the detection of the female.

The researchers demonstrated that the octopaminergic system in the mosquito ear can be targeted by insecticides. Mosquito mating is a bottleneck for mosquito survival, so identifying new targets to disrupt it is key to controlling disease-transmitting mosquito populations.

Source: University College London

Clinical Researchers Beware – ChatGPT is not a Reliable Aid

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Clinicians are all too familiar with the ‘Google patient’ who finds every scary, worst-case or outright false diagnosis online on whatever is ailing them. During COVID, misinformation spread like wildfire, eroding the public’s trust in vaccines and the healthcare profession. But now, AI models like ChatGPT can be whispering misleading information to the clinical researchers trying to produce real research.

Researchers from CHU Sainte-Justine and the Montreal Children’s Hospital recently posed 20 medical questions to ChatGPT. The chatbot provided answers of limited quality, including factual errors and fabricated references, show the results of the study published in Mayo Clinic Proceedings: Digital Health.

“These results are alarming, given that trust is a pillar of scientific communication. ChatGPT users should pay particular attention to the references provided before integrating them into medical manuscripts,” says Dr Jocelyn Gravel, lead author of the study and emergency physician at CHU Sainte-Justine.

Questionable quality, fabricated references

The researchers drew their questions from existing studies and asked ChatGPT to support its answers with references. They then asked the authors of the articles from which the questions were taken to rate the software’s answers on a scale from 0 to 100%.

Out of 20 authors, 17 agreed to review the answers of ChatGPT. They judged them to be of questionable quality (median score of 60%). They also found major (five) and minor (seven) factual errors. For example, the software suggested administering an anti-inflammatory drug by injection, when it should be swallowed. ChatGPT also overestimated the global burden of mortality associated with Shigella infections by a factor of ten.

Of the references provided, 69% were fabricated, yet looked real. Most of the false citations (95%) used the names of authors who had already published articles on a related subject, or came from recognised organisations such as the Food and Drug Administration. The references all bore a title related to the subject of the question and used the names of known journals or websites. Even some of the real references contained errors (eight out of 18).

ChatGPT explains

When asked about the accuracy of the references provided, ChatGPT gave varying answers. In one case, it claimed, “References are available in Pubmed,” and provided a web link. This link referred to other publications unrelated to the question. At another point, the software replied, “I strive to provide the most accurate and up-to-date information available to me, but errors or inaccuracies can occur.”

Despite even the most ‘truthful’ of these responses, ChatGPT poses hidden risks to academic, the researcher say.

“The importance of proper referencing in science is undeniable. The quality and breadth of the references provided in authentic studies demonstrate that the researchers have performed a complete literature review and are knowledgeable about the topic. This process enables the integration of findings in the context of previous work, a fundamental aspect of medical research advancement. Failing to provide references is one thing but creating fake references would be considered fraudulent for researchers,” says Dr Esli Osmanlliu, emergency physician at the Montreal Children’s Hospital and scientist with the Child Health and Human Development Program at the Research Institute of the McGill University Health Centre.

“Researchers using ChatGPT may be misled by false information because clear, seemingly coherent and stylistically appealing references can conceal poor content quality,” adds Dr Osmanlliu.

This is the first study to assess the quality and accuracy of references provided by ChatGPT, the researchers point out.

Source: McGill University Health Centre

Deadline for Public Comments on NHI Bill Pushed Back

The Select Committee on Health and Social Services has extended the deadline for public comments on the contentious National Health Insurance (NHI) Bill by two weeks, according to a report from Business Insider. In its announcement, the Committee said that it had received numerous requests from stakeholders to extend the date on written submissions for the act.

The committee has therefore extended the deadline from Friday, 1 September 2023 to Friday, 15 September 2023. The Bill is already before the National Council of Provinces (NCOP) after being passed by Parliament in June, in spite of vehement opposition. Once past the NCOP, which seems all but assured given its stubborn progress, it will then be sent to President Cyril Ramaphosa to be signed into law.

Contact details to submit enquiries or written submissions are at the end of the article.

Controversy continues unabated

An unrelenting barrage of criticism has been directed at the Bill, which so far has shown little change in response and according to many its constitutionality is questionable. While stakeholders are generally for universal healthcare and the idea of an NHI, the current public healthcare system is already under dire pressure, being underfunded, under-resourced in terms of skilled professionals and equipment, and riddled with corruption.

Indeed, South Africa would be the first country in the world to completely bring all healthcare. The fact that other countries with better governance track records and more resources have not done so has been brought up as a red flag.

Another is the vague notion that the government will pay for the scheme somehow – which inevitably means reaching into taxpayers’ wallets. The estimated cost of R300 billion and R660 billion a year will be by far the largest single government expense in a time of shrinking funds.

“Looking at 2026 – the year in which the NHI is supposed to be implemented – an enormous extra R296 billion will be required in order to balance the books,” the Solidarity Research Institute (SRI) said.

“This is unheard of for a middle-income country, where spending on education usually enjoys the highest priority. While more affluent countries spend more on healthcare, social grants usually receive the highest priority, never health,” said the SRI.

Options to foot the bill range from a staggering 40% surcharge on income tax to a payroll tax of 13.4%, which Professor Alex van den Heever criticised as being “incredibly naïve set of fiscal proposals that you cannot even consider implementing.” Discovery Health CEO Ryan Noach warned of a tax revolt if the government attempts to pay for this.

Practical allternatives on offer include a public-private partnership as envisaged by Business Leadership South Africa CEO Busi Mavuso.

Enquiries, as well as written submissions, can be directed to Ms M Williams, Select Committee on Health and Social Services, e-mail mawilliams@parliament.gov.za.

Pig-to-human Kidney Xenotransplant is the Longest Successful One Yet

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Surgeons at NYU Langone Health have transplanted a genetically engineered pig kidney that continues to function well after 32 days in a man declared dead by neurologic criteria and maintained with a beating heart on ventilator support. This represents the longest period that a gene-edited pig kidney has functioned in a human, and the latest step toward the advent of an alternate, sustainable supply of organs for transplant.

Led by Robert Montgomery, MD, DPhil, the procedure was performed on July 24, 2023 and marks the fifth xenotransplant performed at NYU Langone. Observation is ongoing and the study will continue through mid-September 2023.

“This work demonstrates a pig kidney – with only one genetic modification and without experimental medications or devices – can replace the function of a human kidney for at least 32 days without being rejected,” said Dr Montgomery, who had previously performed the world’s first genetically modified pig kidney transplant into a human decedent in 2021.

Removing single troublesome gene

The first hurdle to overcome in xenotransplants is preventing so-called hyperacute rejection, which typically occurs just minutes after an animal organ is connected to the human circulatory system. By “knocking out” the gene that encodes the biomolecule known as alpha-gal, responsible for a rapid antibody-mediated rejection of pig organs by humans, immediate rejection has been avoided in all five xenotransplants at NYU Langone. Additionally, the pig’s thymus gland, which is responsible for educating the immune system, was embedded underneath the outer layer of the kidney to stave off novel, delayed immune responses. The combination of modifications has been shown to prevent rejection of the organ while preserving kidney function.

To ensure the body’s kidney function was sustained solely by the pig kidney, both of the transplant recipient’s native kidneys were surgically removed. One pig kidney was then transplanted and started producing urine immediately without any signs of hyperacute rejection. During the observation phase, intensive care clinical staff maintained the decedent on support while the pig kidney’s performance was monitored and sampled with weekly biopsies. Levels of creatinine, a bodily waste product found in the blood and an indicator of kidney function, were in the optimal range during the length of the study, and there was no evidence on biopsy of rejection.

The surgery was the latest in a larger study approved by a specific research ethics oversight board at NYU Langone and was performed after consultation with the New York State Department of Health. This important research, which study leaders say could save many lives in the future, was made possible by the family of a 57-year-old male who elected to donate his body after a brain death declaration and a circumstance in which his organs or tissues were not suitable for transplant.

A big leap toward a new organ source

“There are simply not enough organs available for everyone who needs one,” said Dr Montgomery, who received a hepatitis C-positive heart transplant himself in 2018. “Too many people are dying because of the lack of available organs, and I strongly believe xenotransplantation is a viable way to change that.”

The kidney and thymus gland used in this procedure were procured from a GalSafeTM pig, an animal engineered by Revivicor, Inc., a subsidiary of United Therapeutics Corporation. In December 2020, the U.S. Food and Drug Administration (FDA) approved the GalSafe pig as a potential source for human therapeutics as well as a food source for people with alpha-gal syndrome, a meat allergy caused by a tick bite.

Less may be more

While previous genetically engineered pig organ transplants have incorporated up to 10 genetic modifications, this latest study shows that a single-gene knockout pig kidney can still perform optimally for at least 32 days without rejection.

“We’ve now gathered more evidence to show that, at least in kidneys, just eliminating the gene that triggers a hyperacute rejection may be enough along with clinically approved immunosuppressive drugs to successfully manage the transplant in a human for optimal performance – potentially in the long-term,” said Dr Montgomery.

The NYU Langone team used standard transplant immunosuppression medications combined with enhanced screening of porcine cytomegalovirus (pCMV) in the donor pig to ensure safety. Recent studies have shown pCMV may affect organ performance and potentially trigger organ failure. No pCMV was detected after 32 days, and close surveillance of porcine endogenous retrovirus (PERV), along with six other viruses of interest, was performed.

Next steps

Monitoring of the pig kidney recipient will continue for another month with permission from the family, ethics committee approval and continued support from United Therapeutics. The additional data from the next several weeks will be analyzed further to develop a deeper understanding of this unique medical advance.

“We think using a pig already deemed safe by the FDA in combination with what we have found in our xenotransplantation research so far, gets us closer to the clinical trial phase,” said Dr Montgomery. “We know this has the potential to save thousands of lives, but we want to ensure the utmost safety and care as we move forward.”

Source: NYU Langone Health

CMS Provides Clarity over BHF’S Court Challenges

Various stakeholders within the medical schemes value chain have sharply raised concerns over the unending court challenges brought by the Board of Healthcare Funders (BHF) against CMS. As an agile regulator, the CMS endeavours to clarify any misconception and confusion over BHF’s court challenges.

Chronology of Events

Initially, the main issue brought by BHF in this case was to request the court to grant them a general exemption for medical schemes to offer low-cost benefit options and to declare an alleged moratorium unlawful by the CMS and Ministry of Health in order to prevent medical schemes from offering low-cost benefit options.

In response, the CMS vehemently opposed the application on the basis that there was no moratorium as alleged by BHF and it would be thus unlawful to grant BHF a general exemption for medical schemes to offer low costs benefit options.

“It must be noted that while the main case/dispute was still ongoing (even after CMS submitted an extensive record of documents that were compliant with relevant information and documents having been exchanged between CMS and BHF), surprisingly BHF brought an interlocutory application alleging that CMS and the Minister were hiding certain information.”

Accordingly, the interlocutory application requested CMS and the NDOH to release an exhaustive list of documents which the CMS believed were irrelevant and had no bearing on the main application.

Despite CMS’s vehement contestation to the court on the additional requested documents by BHF, Judge Botha granted the BHF the order they sought, and the CMS, as well as the Minister of Health were ordered to produce the documents listed in Notice in terms of Rule 30A within 10 (ten) days of the Court Order, being 24 July 2023. 

Before the expiration of rule 18 of the superior court, CMS filed leave to appeal the court order of Judge Botha as CMS believed that the order was flawed in law and that the judge had no reasons for ordering CMS and the Minister to produce those documents.

While the CMS legal team was studying the order, BHF concurrently lodged a contempt of court on an urgent basis.

CMS, through its attorneys, moved swiftly and wrote to BHF urging them to withdraw the contempt application as the CMS had already lodged its leave to appeal the court order of Judge Botha and this meant that the court order by Judge Botha would been suspended. 

BHF refused to withdraw the contempt application and the application was heard on 8th August 2023 and the court dismissed BHF’s application on 10 August 2023 with costs in favour of CMS and Minister.

Citing Judge E van der Schyff who emphasised that “in the Practice Manual of the Gauteng High Court Division that while an application maybe urgent, it may not be sufficiently urgent to be heard at the time selected by an applicant” and also strongly highlighted that it does “not mean that applicants can indiscriminately approach the urgent court on the basis of extreme urgency without having regard to the context and facts of each individual application.”

Based on this order, the contempt application is now in our view moot or rather has been overtaken by the leave to appeal lodged by CMS and the Minister and CMS/NDOH. The leave to appeal will be heard somewhere September 2023.

The main application brought by BHF is likely to be heard in later parts of 2024.

An Antibiotic Alternative to Treating Kids’ Ear Infections

This illustration depicted a three-dimensional (3D), computer-generated image, of a group of Gram-positive, Streptococcus pneumoniae bacteria. The artistic recreation was based upon scanning electron microscopic (SEM) imagery.

Doctors typically treat paediatric ear infections with antibiotics, but children don’t always complete the full course, accelerating resistance to these medications. Today, researchers report developing a single-use nanoscale system that’s unlikely to generate resistance. Using a compound similar to bleach in test animals, they show it can kill off Streptococcus pneumoniae, a common cause of ear infections, and it could someday be easily applied as a gel.

The researchers will present their results at the meeting of the American Chemical Society (ACS).

“We initially conceived of this idea by looking at the household cleaner bleach. Even though it has been used since the 19th century, bacteria do not appear to have developed any widespread resistance to this cleaner,” says Rong Yang, PhD, the project’s principal investigator.

But Yang quickly warns that people should not treat infections with bleach. The solution sold at stores is highly concentrated and caustic, but when used in a properly controlled manner at extremely low concentrations, the active ingredient in bleach is considered compatible with living tissue.

After realising that the active ingredient in the household cleaner could circumvent antibiotic resistance, the Cornell University researchers, set out to tackle a nearly universal childhood scourge: acute ear infections. These infections affect more than 95% of children in the US, and treatment typically requires taking antibiotics for five to 10 days. However, these regimens can cause problematic side effects, leading some families to discontinue the medication prematurely, particularly if symptoms resolve. But using these medications improperly can speed up the development of antibiotic resistance, which makes infections more difficult, if not impossible, to treat. This issue ranks among the biggest threats to global health, according to the World Health Organization.

Bacteria have more success fighting against some substances than others. Hypochloric acid from bleach belongs to a family of compounds, known as hypohalous acids, to which bacteria have yet to develop any significant resistance; most likely because of the numerous ways these highly reactive acids damage microbial cells, Yang says.

Because these substances break down quickly, Yang and her colleagues sought to generate one of them on an as-needed basis behind the eardrum in the middle ear, where ear infections occur. They found inspiration in an enzyme from giant kelp, which converts hydrogen peroxide (H2O2) to hypobromous acid (HOBr), a chemical relative of bleach.

Streptococcus pneumoniae, a frequent cause of ear infections, produces H2O2 to fight off other microbes. To mimic the kelp enzyme, which contains the metal vanadium, Yang and her colleagues designed nanowires made of vanadium pentoxide (V2O5). These produce HOBr only in the presence of the H2O2-producing bacteria, and their rod-like shape helps to keep them in place by reducing their ability to diffuse into body fluids.

In tests on chinchillas, which contract ear infections from the same pathogens as human children, they succeeded in eliminating most of the S. pneumoniae. Yang and colleagues found that after treatment with the nanowires, the animals’ once-inflamed eardrums returned to normal. Meanwhile, tests in healthy animals found evidence that the treatment did not interfere with hearing.

For these experiments, the researchers injected the nanowires directly into the middle ear. In more recent work in chinchillas, they developed a less invasive, more practical method for delivering the wires. By decorating the nanowires with peptides known to transport small particles across the eardrum, Yang and her team found they could deliver the treatment topically as a gel deposited into the ear canal. Once the gel was applied, the nanowires within it went through the intact tissue. They are also exploring other approaches for passing the nanowires through the eardrum.

Because other ear-infection-causing bacteria do not produce H2O2, the researchers are currently examining whether this system is effective in the presence of microbes other than S. pneumoniae, and how they might adapt it to fight the other bugs.

The researchers have not yet done studies to determine how long the system stays in place, although their evidence suggests the nanowires drain out of the middle ear after the infection clears. However, Yang suspects they could adapt the nanowires’ properties to stay in place for long periods afterward. This latter approach could make it possible to prevent recurrent infections that plague many children.

“If the bacteria return, the system could restart, so children wouldn’t need antibiotics repeatedly and breed more resistance along the way,” Yang says.

A video on the research is available at www.acs.org/Earaches.

Source: American Chemical Society

Liraglutide Boosts Associative Learning in People with Obesity

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Obesity leads to altered energy metabolism and reduced insulin sensitivity of cells. The so-called “anti-obesity drugs” such as liraglutide are increasingly used to treat obesity and have caused tremendous interest, especially in the USA. Researchers in Germany have now shown in people with obesity that reduced insulin sensitivity affects learning of sensory associations. The results, published in Nature Metabolism, showed that a single dose of liraglutide was able to normalise these changes and restore the underlying brain circuit function.

The brain must be able to form associations in order to control behaviour. This involves, for example, associating a neutral external stimulus with a consequence following the stimulus. In this way, the brain learns what the implication of handling of the first stimulus are. Associative learning is the basis for forming neural connections and gives stimuli their motivational force. It is essentially controlled by a brain region called the dopaminergic midbrain. This region has many receptors for the body’s signalling molecules, such as insulin, and can thus adapt behaviour to the body’s physiological needs.

But what happens when the body’s insulin sensitivity is reduced due to obesity? Does this change brain activity, ability to learn associations and thus behaviour? Researchers at the Max Planck Institute for Metabolism Research have now measured how well the learning of associations works in participants with normal body weight (high insulin sensitivity, 30 volunteers) and in participants with obesity (reduced insulin sensitivity, 24 volunteers), and if this learning process is influenced by the anti-obesity drug liraglutide.

Low insulin sensitivity reduces the brain’s ability to associate sensory stimuli.

In the evening, they injected the participants with either the drug liraglutide or a placebo in the evening. Liraglutide is a so-called GLP-1 agonist, which activates the GLP-1 receptor in the body, stimulating insulin production and producing a feeling of satiety. It is often used to treat obesity and type 2 diabetes and is given once a day. The next morning, the subjects were given a learning task that allowed the researchers to measure how well associative learning works. They found that the ability to associate sensory stimuli was less pronounced in participants with obesity than in those of normal weight, and that brain activity was reduced in the areas encoding this learning behaviour.

After just one dose of liraglutide, participants with obesity no longer showed these impairments, and no difference in brain activity was seen between participants with normal weight and obesity. In other words, the drug returned the brain activity to the state of normal-weight subjects.

“These findings are of fundamental importance. We show here that basic behaviours such as associative learning depend not only on external environmental conditions but also on the body’s metabolic state. So, whether someone has overweight or not also determines how the brain learns to associate sensory signals and what motivation is generated. The normalisation we achieved with the drug in subjects with obesity, therefore, fits with studies showing that these drugs restore a normal feeling of satiety, causing people to eat less and therefore lose weight,” says study leader Marc Tittgemeyer from the Max Planck Institute for Metabolism Research.

“While it is encouraging that available drugs have a positive effect on brain activity in obesity, it is alarming that changes in brain performance occur even in young people with obesity without other medical conditions. Obesity prevention should play a much greater role in our healthcare system in the future. Lifelong medication is the less preferred option in comparison primary prevention of obesity and associated complications,” says Ruth Hanßen, first author of the study and a physician at the University Hospital of Cologne.

Source: Max Planck Institute for Biology of Ageing

Mediterranean Lifestyle Linked to Lower Risk of All-cause and Cancer Mortality

in Mayo Clinic Proceedings.

People who adhere to a Mediterranean lifestyle, which involves a plant-rich diet, adequate rest, physical activity and socialisation, have a lower risk of all-cause and cancer mortality, according to a new study in Mayo Clinic Proceedings. People who adhered to the lifestyle’s emphasis on rest, exercise, and socialising with friends had a lower risk of cardiovascular disease mortality.

While many studies have established the health benefits of a Mediterranean diet and lifestyle, there are few studies on the diet outside of its region of origin. “This study suggests that it’s possible for non-Mediterranean populations to adopt the Mediterranean diet using locally available products and to adopt the overall Mediterranean lifestyle within their own cultural contexts,” said lead author Mercedes Sotos Prieto, Ramon y Cajal research fellow at La Universidad Autónoma de Madrid and adjunct assistant professor of environmental health at Harvard Chan School. “We’re seeing the transferability of the lifestyle and its positive effects on health.”

Led by La Universidad Autónoma de Madrid and Harvard T.H. Chan School of Public Health, the study analysed the habits of 110,799 members of the UK Biobank cohort, a population-based study across England, Wales, and Scotland using the Mediterranean Lifestyle (MEDLIFE) index, which is derived from a lifestyle questionnaire and diet assessments. Participants, who were between the ages of 40 and 75, provided information about their lifestyle according to the three categories the index measures: “Mediterranean food consumption” (intake of foods part of the Mediterranean diet such as fruits and whole grains); “Mediterranean dietary habits” (adherence to habits and practices around meals, including limiting salt and drinking healthy beverages); and “physical activity, rest, and social habits and conviviality” (adherence to lifestyle habits including taking regular naps, exercising, and spending time with friends). Each item within the three categories was then scored, with higher total scores indicating higher adherence to the Mediterranean lifestyle.

The researchers followed up nine years later to examine participants’ health outcomes. Among the study population, 4247 died from all causes; 2401 from cancer; and 731 from cardiovascular disease. Analysing these results alongside MEDLIFE scores, the researchers observed an inverse association between adherence to the Mediterranean lifestyle and risk of mortality. Participants with higher MEDLIFE scores were found to have a 29% lower risk of all-cause mortality and a 28% lower risk of cancer mortality compared to those with lower MEDLIFE scores. Adherence to each MEDLIFE category independently was associated with lower all-cause and cancer mortality risk. The “physical activity, rest, and social habits and conviviality” category was most strongly associated with these lowered risks, and additionally was associated with a lower risk of cardiovascular disease mortality.

Source: Harvard T.H. Chan School of Public Health