Researchers from TwinsUK have found that rather than being protective, high protein intake is associated with loss of muscle mass in healthy over-60s.
This surprising finding comes from a study of 3,302 twins from the TwinsUK cohort.
Sarcopenia is associated with ageing and occurs when there is an accelerated loss of skeletal muscle mass and function. This can lead to negative outcomes such as frailty, reduced function in day-to-day activities, and increased risk of falls. The study aimed to investigate factors linked with skeletal muscle strength, mass and sarcopenia, particularly intake of protein, and to evaluate if shared twin characteristics are important.
The team studied twins who consumed the optimal recommended protein intake as the reference group (1.0–1.3 g/kg/day) and found that there was no significant link between protein intake (neither high nor low) and low muscle strength, or between low intake of protein and sarcopenia.
Results showed that high protein intake on the other hand was associated with decreased muscle mass, while low protein intake was protective. High protein intake was also linked with sarcopenia, even after adjusting for demographic, anthropometric (physical measures of a person’s size, form, and functional capacities) and dietary factors.
The study also found that the strength of muscles is linked with age, education, income, diet, appetite and diversity in the gut microbiome. However, the link between muscle strength and weight, body mass index, healthy eating index, protein intake, and gut microbiome diversity were not significantly influenced by shared twin factors. This means that treatments targeting these factors may be effective in preventing or treating sarcopenia.
First author Dr Mary Ni Lochlainn explains:
“We know high quality protein intake is essential for muscle health, however, it is important to consider that not all sources of protein contain the full range of essential amino acids, and that it may be important to eat some sources of protein in moderation.”
“While our participants were healthy volunteers, the results give valuable insight into the link between diet and sarcopenia. Further research is needed to investigate this further, including looking at longitudinal data in cohorts with an increased number of participants who live with sarcopenia.”
A recent study has found that brain-age could help with early detection of dementia in patients. The team, which included TwinsUK Clinical Director Professor Claire Steves, found that patients who visited memory clinics with brains that appeared to look older had a higher risk of dementia.
Dementia is a general term for loss of memory, language, problem-solving and other thinking abilities that are severe enough to affect everyday activities.
Some years ago, members from TwinsUK took part in an MRI brain study which was used to define a brain-age score – a way of marking the age of a person from the structure of their brain. This data was used to develop a way of determining whether someone’s brain looks older or younger than their years. In the present study, the team analysed MRI brain scans from patients referred to memory clinics to determine their brain-age, and tracked which patients developed dementia through linking to their electronic health records in the years that followed.
The researchers found that patients with higher brain-age were more likely to receive a subsequent dementia diagnosis. The results from this study show that neuroimaging biomarkers like brain-age are useful clinically in managing people with memory problems. The next stage is for doctors to put this into practice regularly, so that everyone affected by memory issues can benefit from it.
Professor Claire Steves said:
“I would like to sincerely thank the twins who contributed to this study by being willing to have MRI scans, as the study shows the potential of using quantitative techniques to study the structure and function of the central nervous system in closing the gap between basic research and it being applied in clinical settings.”
The number of people with dementia around the world is increasing, and this is driving research to improve ways of identifying earlier individuals at greatest risk of being diagnosed with the disease. Being able to identify dementia in patients early on has important significance for planning future care, interventions, and clinical trials.
One in six (17%) middle-aged people who report being infected by SARS-CoV-2 also report long COVID symptoms, while this falls to one in 13 (7.8%) among younger adults who reported having Covid-19, according to a new study led by King’s and UCL which is now published in Nature.
The preliminary findings, part of the UKRI-NIHR funded multi-institution CONVALESCENCE study and submitted to the preprint server medRxiv, also found that women were 50% more likely to report long COVID than men, and that the risk for long COVID symptoms increases with age, is linked to poorer pre-pandemic mental and physical health and is associated with a previous diagnosis of asthma. Non-white ethnic minority groups had lower odds of reporting long COVID (about 70% less likely).
Using a stricter definition of long COVID as impacting routine daily activities, the researchers found that it affected 1.2% of 20-year-olds who had Covid-19, but 4.8% of people in middle age.
The researchers analysed anonymised data from 1.2 million primary health records across the UK together with 10 population-based cohort studies with 45,096 participants. Using existing cohort studies, whose participants are surveyed regularly, allowed the research team to include cases not reported to the GP and to look at people’s health before the pandemic.
Knowing which factors increase the risk of long COVID is an important first step in understanding how best to prevent and treat this condition.
Professor Nishi Chaturvedi (MRC Unit for Lifelong Health and Ageing at UCL), who leads the ongoing CONVALESCENCE study, said: “Getting consistent findings from this combination of many different studies gives us greater confidence that our findings are robust, which is critical given that we know so little about long COVID.”
First author Dr Ellen Thompson, of King’s College London, said:
“It’s really important to identify risk factors in the population so we can prepare and devise prevention strategies, protecting people at increased risk of poor outcomes from COVID-19.”
First author Dr Dylan Williams (MRC Unit for Lifelong Health & Ageing at UCL) said:
“Amassing this body of evidence would usually take many months or years to assemble but we achieved this more quickly through massive, constant collaboration by researchers at many different institutions.
Dr Claire Steves from the School of Life Course Sciences said:
“Our findings hint at the mechanisms behind long COVID. Next, we need to identify the predispositions that might explain, for example, why women or individuals with asthma appear to be at higher risk. Could a liability to suffer from autoimmunity or allergies play a role? Establishing concrete research avenues to go down will eventually lead to benefits for people with long COVID.”
The study forms part of the larger COVID-19 Longitudinal Health and Wellbeing National Core Study, which is investigating the health, social and economic impacts of the COVID-19 pandemic by combining rich pre-COVID data collected from participants of numerous national research studies with national anonymised electronic health records.
The researchers investigated if the risks of developing long-term Covid symptoms differed by several pre-pandemic socioeconomic and health characteristics. Coordinated analyses of the longitudinal studies and health records data showed consistently that female sex and increasing age (up to 70 years) were associated with increased odds of long COVID.
Pre-existing adverse mental health was associated with a 50% increase in the odds of reporting long COVID, while asthma was the only specific prior medical condition consistently associated with greater risk of developing lasting Covid-19 symptoms (a 32% increase). Participants were identified as having pre-existing adverse mental health if they had been diagnosed with one of a number of conditions such as depression and bipolar disorder, or their responses to questionnaires indicated they had a mental health condition before the pandemic.
Analysis was conducted on 6,899 individuals self-reporting COVID-19 from 45,096 surveyed adult participants of ongoing longitudinal studies in the UK, and on 3,327 cases assigned a long COVID code in primary care electronic health records out of 1,199,812 adults diagnosed with acute COVID-19. Long COVID, identified as Post-COVID-19 syndrome in the study, is defined as symptoms persisting for longer than 12 weeks after the initial infection.
The research team included researchers at the Universities of Bristol, Edinburgh, Glasgow, and Oxford, as well as the London School of Hygiene & Tropical Medicine, and the Bradford Royal Infirmary.
Dr Fiona Glen, programme director for the NICE Centre for Guidelines, said:
“There is still much we do not know about the long-term effects of COVID-19. We continue to monitor and assess the latest evidence on the long-term effects allowing us to continuously update our guideline recommendations. We welcome this new research which will ensure we have a better understanding of how to manage the care and treatment of patients with prolonged symptoms of COVID-19.”
Exposure to natural environments, also known as greenspace, has been shown to have a positive influence on our health, but the mechanisms as to why are still not clear. We know from previous research that gut bacteria is linked with inflammatory illnesses; inflammatory illnesses are also more prevalent in urban areas and in individuals who have lower levels of exposure to greenspace. Therefore, gut bacteria could act as one of the links between greenspace and health.
The team studied 2,443 participants from the TwinsUK cohort to see if there was a difference in gut bacteria in individuals living in rural and urban environments. The researchers looked at the amount of greenspace at three different distances from a participant’s home: 800 m, 3000 m, and 5000 m. The aim was to understand if there was any evidence of bacteria differing with the amount of greenspace.
The team found there were differences in bacteria between different greenspace areas and when comparing rural versus –urban microbes. One hypothesised reason could be that people are exposed to a range of microorganisms and therefore have a stronger immune system as they are exposed to a wider range of bacteria. Levels of bacteria associated with disease were higher in individuals living in more urban environments compared to rural environments.
A limitation of the study was the broad interpretation of “greenspace” as being any area in a non-urban environment. This meant that factors like the accessibility of land or the type and quality of habitats that were present could not be considered. Further work could design experiments to understand this further by comparing urban areas with high, accessible greenspace with urban areas of low, accessible greenspace.
The different microrganisms residing along the human digestive tract, along with the things these microbes produce is collectively called the human gut microbiome. It has a crucial role as it interacts with the immune system, is vital for processing nutrients and protects individuals against pathogens.
First author Ruth Bowyer said:
“The results show that there are geographical patterns in the composition of the microbiota which does not appear to be explained by diet, BMI (Body Mass Index), and health deficit. Therefore, the results bring to light the potential importance of considering non-lifestyle factors that could affect microbiota composition.”
A new study has found women ‘age’ significantly faster in the perimenopausal period, based on analysis of the IgG glycome. This finding indicates the potential of using the IgG glycome composition as an early predictor for perimenopause.
The study, published in iScience and led by a team of researchers from the Genos Glycoscience Research Laboratory in Zagreb, Croatia, Newson Health Menopause & Wellbeing in Stratford upon Avon and King’s College London followed nearly 2000 women for 15 years and analysed their IgG glycans several times during that period. IgG glycans, otherwise known as immunoglobulin G glycome, is an abundant antibody and has been shown to be a biomarker of an individual’s health.
Researchers analysed IgG glycome composition in 5,080 samples from 1,940 females during their transition from before menopause (premenopause) to postmenopause. Many of these samples were taken from TwinsUK which is the largest twin registry in the UK and led by researchers from King’s College London.
Analysis of the IgG glycome in multiple samples from the same individuals was able to show the association between perimenopause and the changes in the IgG glycome composition. This period showed the IgG glycome changing from an inflammation-suppressive to proinflammatory. While this is common as we age, researchers saw this change happen rapidly as women transitioned from a regular cycle to menopause.
This change in IgG glycans is associated with many health risks that accompany menopause. In some diseases like rheumatoid arthritis and cardiovascular diseases, this change can occur years before disease onset. This suggests glycans and chronic inflammation is linked and the transformation of IgG glycans plays a part in developing the disease.
Perimenopause can last up to 15 years and is challenging to diagnose due to highly irregular hormonal cycles. As a result of poor awareness and inappropriate use of hormonal tests, women are often misdiagnosed with conditions such as fibromyalgia, migraines, depression, or chronic fatigue syndrome and are frequently prescribed antidepressants despite the lack of evidence to support their use to improve the low mood associated with perimenopause or menopause. This study shows it may be possible to use IgG glycans to predict perimenopause.
Senior author Dr. Cristina Menni from King’s College London said:
“Perimenopause is poorly diagnosed due to highly irregular hormonal cycles and symptoms that can last for as long as 15 years. Currently, there is no accurate diagnostic test for perimenopause. Adding an easily quantifiable novel early biomarker of perimenopause could be a valuable improvement to current clinical praxis.”
In October 2020, the National Core Studies commenced as part of the UK’s response to the COVID-19 pandemic. The National Core Studies are using health data to rapidly inform policy to help us get through the pandemic.
TwinsUK is closely involved in the Longitudinal Health and Wellbeing National Core Study, which aims to understand the health, social and economic impacts of the pandemic. We are one of many UK longitudinal population cohorts taking part in the project.
This large, multi-institution team is working together to answer key questions across several different areas. Current priority research questions include: how was healthcare disrupted by the pandemic; did government schemes such as furlough help; how was mental health impacted by the pandemic; how well do vaccines work; and what are the short and long-term consequences of infection on health.
The team has prioritised questions that harness the unique aspects of cohorts like TwinsUK, such as extensive pre-pandemic data. By working together and triangulating analysis in longitudinal health cohorts and electronic health records, we can provide robust evidence to inform policy.
Findings are regularly reported to the government’s Scientific Advisory Group for Emergencies (SAGE) and the Cabinet and have influenced NICE guidelines, which dictate how to treat medical conditions.
Results and impact so far
Every day we are learning more about COVID-19 and its impact, thanks to our TwinsUK members taking part in studies and questionnaires and our researchers rapidly analysing all the data coming in. Below are some key examples to date that TwinsUK was involved in:
Society and Health: The coronavirus job retention scheme was associated with the preservation of health behaviours (eating, drinking, smoking, sleeping habits) similar to those remaining in employment, and more favourable to those who become unemployed. Also, while mental and social wellbeing declined in those furloughed, the effects were far less than those who lost their jobs. This suggests that social protection policies should be implemented in the post-pandemic recovery period and during future economic crises.
Healthcare Disruption: The pandemic led to unequal healthcare disruptions. Females, ethnic minorities, and disadvantaged people were most affected. Action is needed to prevent the widening of existing health inequalities, and efforts to ensure continuity of care during pandemic-related disruptions may need to be more clearly targeted to those who most need that care.
Mental Health: People with prior mental ill-health were hit harder by pandemic disruption. Inequality between those with and without mental health problems should be considered when provisioning current and post-pandemic health, economic, and well-being support. Also, a substantial deterioration in mental health seen during the first lockdown did not reverse when lockdown was lifted, suggesting that lockdown alone was not responsible for the decline in mental health. There is a need for investment in mental health support to address all underlying causes.
Long COVID: We found that long COVID is associated with women, middle age, and pre-existing health factors, including asthma. Understanding why different groups of people have different levels of risk could both identify high-risk groups and help us understand how best to prevent and treat long COVID.
What are we working on now?
We are currently working with collaborators at University College London (UCL) to carry out a detailed study of how COVID-19 affects the body. This will help us understand long Covid, which is when infected individuals continue to experience symptoms for many weeks and even months after infection.
This study will recruit people with a range of COVID-19 experiences, and participants will be invited to UCL’s clinic in London for a full day of checks and health tests, including an MRI scan. TwinsUK is the first cohort to recruit participants to CONVALESCENCE, which aims to recruit 800 participants in total. We have recruited more than 150 twins to take part, mainly in twin pairs.
A big thank you
We would like to take this opportunity to thank our twins for everything they have contributed to this vital research, both by taking part in sample collection and questionnaires during the pandemic, but also for all of the data they have previously provided to TwinsUK, which is essential to understand how the pandemic has affected health.
TwinsUK’s Dr. Claire Steves is a senior researcher working across the National Core Study and CONVALESCENCE. Dr. Steves explained:
“There is a wealth of data in the UK’s population cohort studies and linked health records. The pandemic has shown the importance of using these unique resources to answer key questions about public health and inform policy as quickly as possible.”
“I would like to thank each and every one of our twins for the vital role they are playing in defeating COVID-19.”
If you would like more information on our COVID-19 research, please click HERE.
Back pain, specifically low back pain, is now the world’s leading cause of disease. It is a huge problem globally and is associated with intervertebral disc degeneration, which is the breakdown of one or more of the cushioned discs that separate the bones of the spine. This causes pain in the back or neck and frequently in the legs and arms.
In some cases, doctors see on scans bone marrow lesions known as ‘Modic change’, which may be associated with low back pain. The aim of this study was to identify whether there is an association between discs next to Modic change and bacterial reproduction. Previous studies have found the growth of bacteria following the removal of degenerated discs after spine surgery.
The TwinsUK team carried out a review of existing research papers, looking at 36 research articles published between 2001 and 2021 reporting human studies which examined the role of bacteria in disc degeneration or Modic change in the bones which form the backbone.
They found that a specific type of bacteria, Cutibactierum acnes, was commonly identified, although this may be because, in many of these studies, researchers have looked for and studied specific bacteria, which means they may have missed other bacteria that were present.
Although several studies in this review reported that the presence of bacteria might be due to infection in the disc, other studies also suggested that contamination may have played a role during study procedures. Some research concluded that bacteria found in the disc may be due to contamination, meaning that the bacteria has come from the air or from the surgical team even though they were scrubbed up and wearing gloves.
Further work is therefore needed to determine whether these bacteria are a result of contamination or represent a real infection of the spine, which contributes to chronic low back pain. This could be done by having a new method approach to look at all the bacteria present, rather than looking for specific bacteria. Researchers will also need to implement a suitable control to test how bacteria could be getting into the disc.
First author, Isabelle Granville Smith, said:
“It is exciting that we might have found contributing factors to disc degeneration as there is not much research on it. We now need to find a way to be able to extract as much information as possible of all the bacteria present rather than looking for specific bacteria.”
Granville Smith et al. 2021. Evidence for infection in intervertebral disc degeneration: a systematic review. European Spine Journal.
New research has demonstrated the heritability of anti-viral antibody selection among a cohort of identical twins.
The study, published today in Cell Press and led by researchers from King’s College London in collaboration with the John Hopkins University, investigated for the first time whether epitope selection – the part of the antigen molecule which an antibody attaches itself – is heritable.
There is a high degree of variability in human immune responses to viral infections. The genetic factors that influence this variability are not well explored. TwinsUK is the UK’s largest adult twin registry consisting of identical twins. Identical (monozygotic) twins come from a single fertilised egg that splits in two and share most of their genetic material. As such, most of their differences (either physical or behavioural) are likely to be the results of environmental factors.
Researchers from TwinsUK compared samples from identical twins with fraternal twins to measure the heritability of the antibody repertoire and identify genetic loci driving antibody responses in humans.
They used VirScan, a virome-wide antibody profiling technology, to measure the heritability of epitope selection.
The results found epitope selection is a heritable trait. They also utilised genome-wide association analysis to identify genetic loci linked to Epstein-Barr Virus (EBV) antibody epitope selection and identified a key role for HLA-DR (MHC-II) in selecting certain dominant EBV epitopes.
First author Dr. Massimo Mangino from King’s College London said:
“Our study represents the first comprehensive investigation of the contributions of genetic and environmental factors to the variation in the antibody responses to viral infections. It highlights the complex relationship between genetic and environment and may provide a novel framework for identifying genes important for pathogen immunity.”
Identical twins are consistently more similar to each other in their concern for nature, environmental movement activism, and personal conservation behaviour than non-identical twins, suggesting there are genetic influences on these traits.
This highlights that the genetic foundation of concern for nature, protecting the environment, and conservation behaviour partially overlap. The genetic correlations amongst the traits could help explain why people who show more concern for nature generally make pro-environmental decisions.
Although results from the study revealed that genetic effects can have a contribution to sustainable behaviours, the researchers explain in their paper that external factors such as education and making conservation behaviours more convenient remain key to encouraging more people towards sustainability.
The researchers used data from the TwinsUK cohort to look at the external and genetic influences that drive individual differences via an online survey on concern for nature, environments, and personal conservation behaviours. They analysed responses from 1,165 twin pairs who participated in the study. The survey results of identical twins were then compared with those of non-identical, who share fewer genes.
One limitation of the study however is that it only surveyed TwinsUK members and at one time-point. Our understanding of a person’s evolving concern for nature and pro-environmental behaviour can be improved by conducting long-term repeated measurements (e.g., looking from child to adult stage of life). Future research studies could therefore carry out repeated measures with a more diverse group of participants to address this.
As the earth is undergoing an environmental crisis due to the negative impacts made on nature by humans, several policies have been proposed in an attempt towards a more sustainable future. The researchers highlighted in their paper that such recommendations have often been disregarded, due to the lack of public support and concern about the crisis. Therefore, a better understanding of people’s support or lack thereof for pro-environmental policies is essential if we want to achieve environmental sustainability.
Night falls across the creeping Thames, glass glitters under the clouded sky, a sliver of the moon breaks through, and stirring autumnal wind crosses the glimmering edifice of St Thomas’ Hospital. Approaching winter seems to hang in the air as shadows lengthen in the evening light. These shadows climb the walls of the hospital.
Some windows are lit, some are not. If ghosts walk the halls, Agnes Elizabeth Jones nods to Florence Nightingale, and William Cheselden wonders how much mercury Isaac Newton ingested.
In the Twin Research clinic, samples of all kinds have been collected. This includes around 300,000 aliquots of blood, stored as serum and plasma. From finger-prick bloods to phlebotomy blood draws, a prowling vampire would be fascinated. Blood and guts are the source from which discoveries spring.
Through corridors, through laboratories under fluorescent light, the penumbral night seeps. Every catalogue of Halloween costumes tends to include nurse’s scrubs – hospitals can be spooky, can be cinematic. So can twins—the unheimlich, or the uncanny, plays on the material of life. I’m reminded of Michael in Caryl Churchill’s play ‘A Number’ pointing out: ‘We’ve got thirty percent the same [DNA] as a lettuce. Does that cheer you up at all? What I love about the lettuce. It makes me feel I belong.’
The trees along the river quiver down below. Curtains flutter in the breeze, woodsmoke drifts from distant bonfires. Beyond the clinic windows, clouds swirl in the sky like a witch’s cauldron.
From the clinic and labs of TwinsUK: Happy Halloween!
