Category: Gender

COVID, Opioid Pandemic Widen Gender Gap in Life Expectancy in the US

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Women have long been known to outlive men. But new research published in JAMA Internal Medicine shows that, at least in the United States, the gap has been widening for more than a decade. Among the factors driving the trend are the COVID pandemic and the opioid overdose epidemic.

The study, led by UC San Francisco and Harvard T.H. Chan School of Public Health, found the difference between how long American men and women live increased to 5.8 years in 2021, the largest since 1996. This is an increase from 4.8 years in 2010, when the gap was at its smallest in recent history.

The pandemic, which took a disproportionate toll on men, was the biggest contributor to the widening gap from 2019–2021, followed by unintentional injuries and poisonings (mostly drug overdoses), accidents and suicide.

“There’s been a lot of research into the decline in life expectancy in recent years, but no one has systematically analysed why the gap between men and women has been widening since 2010,” said the paper’s first author, Brandon Yan, MD, MPH, a UCSF internal medicine resident physician and research collaborator at Harvard Chan School.

Life expectancy in the US dropped in 2021 to 76.1 years, falling from 78.8 years in 2019 and 77 years in 2020.

The shortening lifespan of Americans has been attributed in part to so-called “deaths of despair.” The term refers to the increase in deaths from such causes as suicide, drug use disorders and alcoholic liver disease, which are often connected with economic hardship, depression and stress.

“While rates of death from drug overdose and homicide have climbed for both men and women, it is clear that men constitute an increasingly disproportionate share of these deaths,” Yan said.

Interventions to reverse a deadly trend

Using data from the National Center for Health Statistics, Yan and fellow researchers from around the country identified the causes of death that were lowering life expectancy the most. Then they estimated the effects on men and women to see how much different causes were contributing to the gap.

Prior to the COVID pandemic, the largest contributors were unintentional injuries, diabetes, suicide, homicide and heart disease.

But during the pandemic, men were more likely to die of the virus. That was likely due to a number of reasons, including differences in health behaviours, as well as social factors, such as the risk of exposure at work, reluctance to seek medical care, incarceration and housing instability. Chronic metabolic disorders, mental illness and gun violence also contributed.

Yan said the results raise questions about whether more specialised care for men, such as in mental health, should be developed to address the growing disparity in life expectancy.

“We have brought insights to a worrisome trend,” Yan said. “Future research ought to help focus public health interventions towards helping reverse this decline in life expectancy.”

Yan and co-authors, including senior author Howard Koh, MD, MPH, professor of the practice of public health leadership at Harvard Chan School, also noted that further analysis is needed to see if these trends change after 2021.

“We need to track these trends closely as the pandemic recedes,” Koh said. “And we must make significant investments in prevention and care to ensure that this widening disparity, among many others, do not become entrenched.”

Source: University of California – San Francisco

Men’s Health Awareness Month: Supporting Men’s Health in the Workplace

To mark Men’s Health Awareness Month, International SOS, the world’s leading health and security risk services company, emphasises the importance of creating supportive workplace environment that foster men’s health and mental wellbeing.

Men’s health remains a significant concern and poorer health profiles for men than for women have been reported, with discrepancies found in metrics including life expectancy, mortality rates, disability-adjusted life years, and non-sex-specific disease death rates.The World Health Organization (WHO) reports that non-communicable diseases (NCDs), are claiming around 74% of all lives lost each year2, and in 2018, NCDs and injuries accounted for 86% of all male fatalities.3

The WHO data shows that men across all socioeconomic groups demonstrate unhealthier smoking practices, unhealthier dietary patterns, higher alcohol consumption levels and higher rates of injuries than women.3 In fact, among the global population that used tobacco in 2020, a significantly higher percentage were men (36.7%), compared to women (7.8%).4 These statistics highlight the need to focus on improving men’s health and organisations can play a vital role in enhancing men’s health within their workplaces.

Men are significantly less likely than women to seek preventive care services, which can often lead to undiagnosed conditions.1 Men are also found to be less likely to have received mental health treatment than women. The stigma attached to illness and men perceiving illness as a weakness are often found to be the reasons why men are not as vocal about their health and mental wellbeing concerns.5

Dr Anthony Renshaw, Regional Medical Director at International SOS, said “Men’s Health Awareness Month provides a crucial opportunity for organisations to re-evaluate their approach to supporting the health and wellbeing of male employees. In addition to physical health, we must also prioritise mental health, as it has a direct impact on overall productivity and workplace satisfaction. Employers can play a pivotal role in fostering open discussions, reducing stigma, and promoting a supportive environment for men to seek the help they may need.”

International SOS offers guidelines for organisations to provide workplace support specific for men’s health and wellbeing with the ‘H-O-P-E’ approach:

  1. Hold workplace men’s forum that can act as a safe space. Having a supportive work environment where everyone, particularly men, know that they are allowed the time to address any health concerns is extremely enabling.
  2. Offer male-specific confidential support from mental health professionals.
  3. Provide your team leads with appropriate training to enable them to spot early signs of poor physical and mental health and know where they can signpost their employees to.
  4. Encourage employees to have regular health check-ups, particularly screening for early detection and treatment of NCDs, as well as a mental health assessment if needed.
  1. The World Journal of Men’s Health | Changing Men’s Health: Leading the Future
  2. World Health Organization (WHO) | Noncommunicable Diseases fact sheet
  3. World Health Organization (WHO) | Men’s Health fact sheet
  4. World Health Organization (WHO) | Tobacco fact sheet
  5. National Institute of Mental Health | Men and Mental Health

Females Less Able to Recover from ACL Injuries

Photo by Andrea Piacquadio on Pexels

Injuries of the knee’s anterior cruciate ligament (ACL) are typically thought to be caused by acute traumatic events, such as sudden twists. Published in the Journal of Orthopaedic Research, new work analysing an animal model of ACLs suggests that such injuries can also occur as a result of chronic overuse, specifically due to a reduced ability to repair microtraumas associated with overuse. Importantly, the team said, females also are less able to heal from these microtraumas than males, which may explain why females are two to eight times more likely to tear their ACL ligaments than males.

“ACL tears are one of the most common injuries, affecting more than 200 000 people in the US each year, and women are known to be particularly susceptible,” said principal investigator Spencer Szczesny, associate professor of biomedical engineering and of orthopaedics and rehabilitation at Penn State. “While recent research suggests that chronic overuse can lead to ACL injuries, until now, no one had investigated the differential biological response of female and male ACLs to applied force.”

In the Penn State-led study, researchers placed ACLs from deceased male and female rabbits in a custom-made bioreactor that simulated the conditions of a living animal but allowed direct observation and measurement of the tissue. Next, they applied repetitive forces to the ACLs that mimicked those that would naturally occur during activities such as standing, walking and trotting and measured the expression of genes related to healing.

In male samples, the team found that low and moderate applied forces, such as those that would occur during standing or walking, resulted in increased expression of anabolic genes, which are related to building molecules needed for healing. By contrast, larger applied forces, such as those that would occur with repetitive trotting, decreased expression of these anabolic genes. For female samples, however, the amount of force applied did not influence the level of anabolic gene expression.

“It didn’t matter whether there was low, medium or high activity for females,” said Lauren Paschall, graduate student in biomedical engineering at Penn State and first author on the paper. “Female ACLs exposed to chronic use just didn’t heal as well as male ACLs, which may explain why women are predisposed to injuries. This supports the hypothesis that noncontact ACL injuries are attributed to microtraumas associated with chronic overuse that predispose the ACL to injury.”

According to the researchers, one explanation for the sex differences the team observed could be due to the higher amounts of oestrogen in females.

“Some studies have found that the overall effect of oestrogen on ACL injury is negative,” Paschall said. “Specifically, studies have shown that human women are more likely to tear their ACLs during the preovulatory phase, when oestrogen levels are high, than during the postovulatory phase, when oestrogen levels are low.”

She said the team plans to further investigate the role of oestrogen on ACL injury.

Szczesny noted that although the team’s study was not in humans, the findings may suggest that providing additional recovery time for women following injuries could be advantageous.

“Ultimately, this work could also help to identify targets for therapeutics to prevent ACL injuries in women,” he said.

Source: Penn State

In Women, Poor Quality Sleep may Increase Hypertension Risk

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Getting enough sleep is becoming more of a challenge in today’s busy society. New research from investigators in the Channing Division of Network Medicine of Brigham and Women’s Hospital, highlights why getting a good night’s sleep is critical to staying healthy. Their research unveils that women who struggled with getting enough sleep were at greater risk of developing hypertension, or high blood pressure. Results are published in the journal Hypertension.

“These findings suggest that individuals who struggle with symptoms of insomnia may be at risk of hypertension and could benefit from preemptive screening,” explained Shahab Haghayegh, PhD, a research fellow at the Brigham and Harvard Medical School. “Hypertension is associated with many other physical and mental health complications. The sooner we can identify individuals with high blood pressure and treat them for it, the better we can mitigate future health issues.”

Haghayegh and colleagues followed 66 122 participants between 25 and 42 years of age in the Nurses’ Health Study II (NHS2) cohort, all without hypertension at the study’s onset, over sixteen years (from 2001 until 2017). Investigators collected information on participants’ age, race, body mass index (BMI), diet, lifestyle, physical activity, history of sleep apnoea, and family history of hypertension and assessed the incidence of hypertension among the group every two years. They first began measuring sleep duration in 2001, then did so again in 2009, recording the average number of hours slept over a 24-hour period. They also tracked sleeping difficulties, such as having trouble falling or staying asleep or waking up early in the morning, collecting responses at several time points throughout the study.

Data analyses revealed that women with sleeping difficulties had higher BMIs, lower physical activity, and poorer diets, on average. Researcher also found that those who struggled with sleep were more likely to smoke and drink alcohol and have previously gone through menopause.

Among the 25 987 cases of hypertension documented over the follow-up, women who slept less than seven to eight hours a night had a significantly higher risk of developing hypertension, according to the data collected. Similarly, women who had trouble falling asleep and staying asleep were also more likely to develop hypertension. Waking up early in the morning was not associated with this increased risk. Notably, these associations, remained significant after controlling for participant shift work schedules (night versus day shifts) and chronotype (morningness versus eveningness).

While the exact nature of the relationship between sleep and risk of hypertension is unknown, Haghayegh said that sleep difficulties can lead to a chain of events that can increase sodium retention, arterial stiffness, and cardiac output, potentially leading to hypertension. Disruptions to the sleep/wake cycle can also influence blood vessel constriction/relaxation activity and the function of cells that regulate the vascular tone.

One limitation is that the study only looked at the association between sleep and hypertension in women, so researchers hope to expand their work to include men and non-binary participants. A second is that researchers could only collect data on sleep quality at select time points throughout the study. Some of the study’s strengths include the larger number of participants and length of follow-up duration.

Haghayegh emphasises that these findings do not indicate causality. He wants to understand why this association exists and how treating one condition may also treat the other. In future clinical studies, he aims to investigate if sleep medications could have a beneficial effect on blood pressure.

“I hope these findings further underscore the crucial role of quality sleep in our overall well-being. The American Academy of Sleep Medicine recommends sleeping seven or more hours a night, and if you cannot fall or stay asleep, it might be worth exploring why that is,” said Haghayegh. “This study highlights yet another reason why getting a good night’s sleep is so important.”

Source: Brigham and Women’s Hospital

Study Suggests Lowering Type 2 Diabetes Diagnosis Threshold in Women under 50

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New research published in the journal Diabetes Therapy suggests that the diagnosis threshold for type 2 diabetes (T2D) should be lowered in women aged under 50 years, since natural blood loss through menstruation could be affecting their blood sugar management.

Analysis of the national diabetes audit results has shown that women of younger age with type 2 diabetes mellitus (T2D) seem to have a higher mortality rate than men. The underlying mechanisms remain unclear. However, it is known that women are on average diagnosed with T2D at a later age than men. In this new study, the authors investigated whether a contributing factor to this late diagnosis may be a sex difference in the levels of glycated haemoglobin (HbA1c) due to haemoglobin replacement linked to menstrual blood loss.

This mechanism behind this could be shorter erythrocyte (red blood cell) survival which results in shorter exposure of haemoglobin to glucose compared with individuals who do not menstruate. Given that the diagnosis of T2D is also based on HbA1c, the use of the same reference range irrespective of age and sex, when a slightly lower point for T2D for premenopausal women may be appropriate, could potentially lead to under diagnosis of T2D in women and missed opportunities for intervention.

The study, by Dr Adrian Heald, Salford Royal Hospital, UK, and colleagues, examined HbA1c testing across seven UK laboratory sites (representing 5% of UK population). They conducted an exploratory analysis in two cohorts: cohort 1 was from one laboratory tested between 2012 and 2019 (146 907 participants). They assessed the sex and age differences of HbA1c in individuals who underwent single testing only, that had not been diagnosed with diabetes and had an HbA1c result of equal to or less than 48mmol/mol (the cutoff for diagnosing diabetes). The process was replicated in cohort 2 results from six laboratories with individuals tested between 2019 and 2021 (total people included 938 678). The possible national impact was estimated by extrapolating findings based on the Office of National Statistics (ONS) England population data and National Diabetes Audit published T2D prevalence and related excess mortality.

At age 50 years, average HbA1c levels in women lag by approximately five years compared to men. The data also show women aged under 50 years old had an HbA1c distribution that was lower than that of men by an average of 1.6mmol/mol (4.7% of the overall mean) while the difference in the distribution of HbA1c for individuals aged 50 years and over was less pronounced.  Further analysis showed that, at HbA1c of 48mmol/mol, 50% fewer women could be diagnosed with T2D than men under the age of 50, whilst only 20% fewer women could be diagnosed with T2D than men over or equal to the age of 50. These findings were consistent with those in cohort 2.

Based on these observations, the authors estimated the effects of lowering the threshold for diagnosis of diabetes from HbA1c (48mmol/mol) by 4.2% to 46mmol/mol for women under the age of 50. This analysis showed that an additional 35 345 currently undiagnosed women in England would be reclassified as being diagnosed with T2D (17% more than the current 208 000 recorded women with T2D aged under 50 years). Lifestyle changes and treatment for diabetes would then be initiated for these women enabling improvement in health outcomes over both the short and longer term.

The authors also highlight that sex and gender difference in adverse cardiovascular risk factors are known to be present prior to the development of T2D. Once diagnosed, the prevalence of atherosclerotic cardiovascular disease is twice as high in patients with diabetes mellitus compared to those without diabetes mellitus. For women, diabetes mellitus is a stronger risk factor for cardiovascular disease than for men: women with diabetes aged 35–59 years have the highest relative cardiovascular death risk across all age and sex groups.

Furthermore, there is disparity in cardiovascular risk factor management between men and women, including in high-risk groups such as women with T2D.  Women are less likely than men to receive treatment and cardiovascular risk reduction interventions that are recommended by international guidelines on diabetes. In addition, concordance with medication or prescription treating cardiovascular risk factors is lower in women than men with T2D, with less use of statins, aspirin and beta blockers. The authors say taken together, these factors mean “timely diagnosis of type 2 diabetes and initiation of preventative treatment has the potential to improve cardiovascular risk profile over lifetime and facilitate longer life quality and expectancy in women. Our findings provide evidence that the HbA1c threshold for this group should be re-evaluated.”

Source: EurekAlert!

A New Model of the Liver Will Help Improve Drug Safety for Women

Improved modelling of male and female livers can help lead to safer drugs

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Researchers report in PLOS Computational Biology that they developed a powerful new tool to understand how medications affect men and women differently, and that will help lead to safer, more effective drugs in the future.

Women are known to suffer a disproportionate number of liver problems from medications but also usually underrepresented in drug testing. To address this, University of Virginia scientists have developed sophisticated computer simulations of male and female livers and used them to reveal sex-specific differences in how the tissues are affected by drugs.

The new model has already provided unprecedented insights into the biological processes that take place in the liver, the organ responsible for detoxifying the body, in both men and women. But the model also represents a powerful new tool for drug development, helping ensure that new medications will not cause harmful side effects.

“There are incredibly complex networks of genes and proteins that control how cells respond to drugs,” said UVA researcher Jason Papin, PhD, one of the model’s creators. “We knew that a computer model would be required to try to answer these important clinical questions, and we’re hopeful these models will continue to provide insights that can improve healthcare.”

Harmful side effects

Papin, of UVA’s Department of Biomedical Engineering, developed the model in collaboration with Connor Moore, a PhD student, and Christopher Holstege, MD, a UVA emergency medicine physician and director of UVA Health’s Blue Ridge Poison Center. “It is exceedingly important that both men and women receive the appropriate dose of recommended medications,” Holstege noted. “Drug therapy is complex and toxicity can occur with subtle changes in dose for specific individuals.”

Before developing their model, the researchers first looked at the federal Food and Drug Administration’s Adverse Event Reporting System to evaluate the frequency of reported liver problems in men and women. The scientists found that women consistently reported liver-related adverse events more often than did men.

The researchers then sought to explain why this might be the case. To do that, they developed computer models of the male and female livers that integrated vast amounts of data on gene activity and metabolic processes within cells. These cutting-edge liver simulations provided important insights into how drugs (xenobiotics) affect the tissue differently in men and women and allowed the researchers to understand why.

They found that xenobiotic metabolism was more active in untreated males, while pentose and glucoronate interconversions were female-biased, suggesting a difference in pretreatment gene expression, which may result in different initial responses of phase I and phase II metabolism to hepatotoxic drugs. They also observed sex-bias in bile acid biosynthesis, which in combination with xenobiotic metabolism, this result may suggest differences in bacterial deconjugation driven by sex differences in the gut microbiome. Differences were also found in several essential metabolic pathways, such as glycolysis/gluconeogenesis, nucleotide metabolism, and lipid metabolism with supporting evidence in human or rat hepatocytes.

“We were surprised how many differences we found, especially in very diverse biochemical pathways,” said Moore, a biomedical engineering student in Papin’s lab. “We hope our results emphasise how important it is for future scientists to consider how both men and women are affected by their research.”

The work has already identified a key series of cellular processes that explain sex differences in liver damage, and the scientists are calling for more investigation of it to better understand “hepatotoxicity” — liver toxicity. Ultimately, they hope their model will prove widely useful in developing safer drugs.

“We’re hopeful these approaches will be help address many other questions where men and women have differences in drug responses or disease processes,” Papin said. “Our ability to build predictive computer models of complex systems in biology, like those in this study, is truly opening all kinds of new avenues for tackling some of the most challenging biomedical problems.”

Source: University of Virginia Health System

Inflammatory Markers of Depression Risk Differ in Boys and Girls

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New research led by King’s College London researchers has found that depression and the risk of depression are linked to different inflammatory cytokines in boys and girls. Previous research has shown that higher levels of inflammatory cytokines are associated with depression in adults, but little is known about this relationship in adolescence.

This study, published in the Journal of Affective Disorders, found that different cytokines were implicated in depression risk and severity in boys compared to girls. The research was part of the IDEA (Identifying Depression Early in Adolescence) project funded by MQ Mental Health Research.

To assess inflammation, researchers measured the blood cytokine levels in 75 adolescent boys and 75 adolescent girls (aged 14–16 years) from Brazil. The 150 participants had been recruited into three groups with equal numbers (50 participants in each group: 25 girls and 25 boys). The groups were those at low-risk for depression and not depressed, those at high risk of depression and not depressed, and those currently experiencing major depressive disorder (MDD).

The findings indicated that there are sex differences between the individual cytokines that are associated with depression in adolescents. Higher levels of the cytokine interleukin-2 (IL-2) were associated with both increased risk for depression and the severity of depressive symptoms in boys, but not in girls. However, higher levels of IL-6 were associated with severity of depression in girls, but not boys. In boys the levels of IL-2 were higher in the high-risk than the low-risk group and even higher in the group diagnosed with depression, indicating that in boys IL-2 levels in the blood could help indicate the onset of future depression.

Dr Zuzanna Zajkowska, Postdoctoral Researcher at King’s IoPPN and first author of the study, said: “This is the first study to show differences between boys and girls in the patterns of inflammation that are linked to the risk and development of adolescent depression.

“We found that the severity of depressive symptoms was associated with increased levels of the cytokine interleukin-2 in boys, but interleukin-6 in girls. We know more adolescent girls develop depression than boys and that the disorder takes a different course depending on sex so we hope that our findings will enable us to better understand why there are these differences and ultimately help develop more targeted treatments for different biological sexes.”

Researchers recruited adolescents from public schools in Brazil. Risk of depression was assessed by a composite risk score for depression based on 11 sociodemographic variables that had been developed as part of the IDEA project. Adolescents completed several questionnaires, self-reporting their emotional difficulties, relationships, experiences, and mood. They also completed a clinical assessment with a child and adolescent psychiatrist.

Senior author on the study Professor Valeria Mondelli, Clinical Professor of Psychoneuroimmunology at King’s IoPPN and theme-lead for Psychosis and Mood Disorders at the NIHR Maudsley BRC, said:

“Our findings suggest that inflammation and biological sex may have combined contribution to the risk for depression. We know that adolescence is a key time when many mental disorders first develop and by identifying which inflammatory proteins are linked to depression and how this is different between boys and girls we hope that our findings can pave the way to understanding what happens at this critical time in life. Our research highlights the importance of considering the combined impact of biology, psychology, and social factors to understand the mechanisms underlying depression.”

Source: King’s College London

The Resilience of Females’ Kidneys is Down to Hormones

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Females’ kidneys are known to be more resilient to disease and injury, so what about them can be applied to treat males’ kidneys? A new USC Stem Cell-led study published in Developmental Cell describes not only how sex hormones drive differences in male and female mouse kidneys, but also how lowering testosterone can “feminise” this organ and improve its resilience.

“By exploring how differences emerge in male and female kidneys during development, we can better understand how to address sex-related health disparities for patients with kidney diseases,” said Professor Andy McMahon, the study’s corresponding author, and the director of the Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research at the Keck School of Medicine of USC.

First authors Lingyun “Ivy” Xiong and Jing Liu from the McMahon Lab and their collaborators identified more than 1000 genes with different levels of activity in male and female mouse kidneys, in a study supported by the National Institutes of Health. The differences were most evident in the section of the kidney’s filtering unit known as the proximal tubule, responsible for reabsorbing most of the nutrients such as glucose and amino acids back into the blood stream. Most of these sex differences in gene activity emerged as the mice entered puberty and became even more pronounced as they reached sexual maturity.

Because female kidneys tend to fare better in the face of disease or injury, the researchers were interested how the gene activity of kidneys becomes “feminised” or “masculinised” – and testosterone appeared to be the biggest culprit.

To feminize the kidneys of male mice, two strategies worked equally well: castrating males before puberty and thus lowering their natural testosterone levels, or removing the cellular sensors known as androgen receptors that respond to male sex hormones.

Intriguingly, three months of calorie restriction – which is an indirect way to lower testosterone – produced a similar effect. Accordingly, calorie restriction has already been shown to mitigate certain types of kidney injuries in mice.

To re-masculinize the kidneys of the castrated males, the researchers only needed to inject testosterone. Similarly, testosterone injection masculinised the kidneys of females who had their ovaries removed before puberty.

The scientists performed some similar experiments with mouse livers. Although this organ also displays sex-related differences, the hormones and underlying factors driving these differences are very different than those at play in the kidney. This suggests that these sex-related organ differences emerged independently during evolution.

To test whether the same genes are involved in sex-related kidney differences in humans, the scientists analysed a limited number of male and female donor kidneys and biopsies. When it came to genes that differed in their activity between the sexes, there was a modest overlap of the human genes with the mouse genes.

“There is much more work to be done in studying sex-related differences in normal human kidneys,” said McMahon. “Given the divergent outcomes for male and female patients with kidney disease and injury, this line of inquiry is important for making progress toward eventually closing the gap on these sex-related health disparities.”

Source: Keck School of Medicine of USC

    Male and Female Immune Systems are Trained Differently

    Scanning electron micrograph of a B cell. Credit: NIH

    When the immune system is compromised due to various conditions and medicines, patients can experience opportunistic infection. Now, researchers reporting in Cell Reports have uncovered a sex-based variance in the trained immune memory response to infection in mice that might translate to humans.

    The researchers, from the University of Missouri School of Medicine, found that female mice were more vulnerable to opportunistic infection from a bacterial pathogen to which they had previously been exposed when progesterone levels were naturally elevated as part of their reproductive cycle.

    “Differences in immune response in males and females have been observed before. For instance, males had increased morbidity and severity of COVID-19 from SARS-CoV-2 infections,” said Dr Adam Schrum, associate professor in the Department of Molecular Microbiology and Immunology. “But females are known to suffer other infections worse than males. Our research found that female mice were far more vulnerable to opportunistic bacterial infection than male mice because of a sex-based difference in their trained immunity.”

    To understand why the immune systems of female and male mice responded differently to a bacterial pathogen, the researchers examined whether the reproductive cycle affected immune training. They found that elevated progesterone levels correlated with lower trained immune responses. To test this more fully, the researchers gave the female mice progesterone blockers and found that their trained immune response was subsequently enhanced.

    “The female mice had significantly restored trained immune response when progesterone was blocked, reaching comparable levels to those of male mice,” said Schrum. “Sex hormone-based modulation of immune function needs more study to be fully understood, but as a first step we can conclude that immune training is influenced by a progesterone-dependent mechanism that results in a sex bias in mice.”

    In addition to further study to understand how and why progesterone specifically influences trained immune responses in mice, the researchers pointed out that because mice have shorter estrous cycles than the human menstrual cycle, further research is needed to understand how sex hormones might affect human immune training.

    Source: University of Missouri-Columbia

    Women Who Reach Their 90s Tend to Have Maintained Stable Weight

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    Reaching the age of 90, 95 or 100, known as exceptional longevity, was more likely for women who maintained their body weight after age 60, according to a multi-institutional study led by University of California San Diego. Older women who sustained a stable weight were 1.2 to 2 times more likely to achieve longevity compared to those who lost 5% of their weight or more.

    In this study published in the Journal of Gerontology: Medical Sciences, researchers investigated the link between weight changes later in life with exceptional longevity among 54 437 women who enrolled in the Women’s Health Initiative, a prospective study investigating causes of chronic diseases among postmenopausal women. Throughout the follow up period, 30 647 (56%) of the participants survived to the age of 90 or beyond.

    Women who lost at least 5% weight were less likely to achieve longevity compared to those who achieved stable weight. For example, women who unintentionally lost weight were 51% less likely to survive to the age of 90. However, gaining 5% or more weight, compared to stable weight, was not associated with exceptional longevity.

    “It is very common for older women in the United States to experience overweight or obesity with a body mass index range of 25 to 35. Our findings support stable weight as a goal for longevity in older women,” said first author Aladdin H. Shadyab, PhD, MPH, associate professor at UC San Diego.

    “If aging women find themselves losing weight when they are not trying to lose weight, this could be a warning sign of ill health and a predictor of decreased longevity.”

    The findings suggest that general recommendations for weight loss in older women may not help them live longer. Nevertheless, the authors caution that women should heed medical advice if moderate weight loss is recommended to improve their health or quality of life.

    The data adds to research connecting weight change and mortality and is notably the first large study to examine weight change later in life and its relation to exceptional longevity.

    Source: University of California – San Diego