Men, These Factors Could Lower Your Testosterone As You Age

Alan Mozes wrote . . . . . . . . .

Men’s testosterone levels remain pretty steady until age 70. After that, production of the male sex hormone starts to decline, new research indicates.

This begs the question: Is testosterone loss among seniors really a function of the normal aging process? Or might it reflect other health issues that often confront men as they get older?

Both may be true, say investigators, with obesity, high blood pressure, diabetes and even marital status among the factors that appear to drive testosterone levels down, in conjunction with age.

When testosterone does fall, the result may be increased weakness and fatigue, diminished sexual performance, loss of muscle mass, and a higher risk for diabetes and dementia.

While you can’t do anything about your age, the findings suggest some positive lifestyle changes might help preserve your masculinity.

Study author Bu Yeap said that after 70 the pituitary gland at the base of the brain actually sends out signals to increase, not decrease, testosterone production.

To find out what might be short-circuiting that signal, the study team analyzed 11 studies from Australia, Europe and North America, involving some 25,000 men in total, said Yeap, an endocrinologist and medical school professor at the University of Western Australia.

All the studies were conducted prior to 2020. In each, men’s testosterone levels were repeatedly measured over time using a technique called mass spectrometry.

Collectively, the data revealed that “on average, testosterone levels are lower in older men compared to younger men,” noted Yeap, who is also a past-president of the Endocrine Society of Australia.

But the analysis also indicated that concentrations of another testosterone-increasing hormone — LH (luteinizing hormone) — goes up after 70. And Yeap noted that testosterone declines directly attributed to age were deemed to be relatively “modest.”

Meanwhile, a wide range of other factors were found to contribute to a post-70 decline in testosterone. These included heart disease, smoking history, cancer, diabetes, high blood pressure, excess body weight, reduced activity and even marriage.

In particular, being overweight or obese was found to have “a much more prominent association” with lower testosterone levels, relative to older age alone, he added.

Men over 70 who took drugs to control high cholesterol levels were also found to have slightly lower testosterone levels, the analysis indicated.

As for marriage and long-term relationships, both were pegged as having a testosterone-dampening impact among seniors.

“A possible explanation,” Yeap suggested, “could be that married men with families might be more stressed, and therefore have lower testosterone levels. But our study wasn’t designed to look further into this result.”

He said the main message is that a range of sociodemographic, lifestyle and medical factors influence testosterone levels in men.

“These need to be considered when doctors interpret testosterone results from individual men, as testosterone levels might be lower than expected in the presence of these conditions, rather than being always due to an (age-related) problem with the testes,” Yeap added.

Dr. Robert Eckel is past president of the American Heart Association, and past president of medicine and science with the American Diabetes Association.

After reviewing the findings, he stressed that the continuously emerging picture of testosterone production dynamics “seems to be more complicated all the time.”

But while noting how “difficult” it is to get a precise handle on the various reasons for falling testosterone, Eckel pointed to two potentially critical factors: LH levels and levels of a key protein (sex hormone-binding globulin, or SHBG) tasked with transporting testosterone throughout the body.

A drop in either — whether due to health complications or the march of time — could lead to a dip in testosterone levels and/or availability, Eckel said.

Since lower testosterone can undermine quality of life, what should a concerned man do?

Eckel and Yeap urged older patients to consult their doctor in order to determine whether or not testosterone supplementation therapy might be appropriate or helpful.

“Testosterone treatment should only be given if there is a clear medical reason,” stressed Yeap, “and always under medical supervision.”

The findings were published online in the Annals of Internal Medicine.

Source: HealthDay

 

 

 

 

Whether Physical Exertion Feels ‘Easy’ or ‘Hard’ May Be Due to Dopamine Levels, Study Suggests

Dopamine, a brain chemical long associated with pleasure, motivation and reward-seeking, also appears to play an important role in why exercise and other physical efforts feel “easy” to some people and exhausting to others, according to results of a study of people with Parkinson’s disease led by Johns Hopkins Medicine researchers. Parkinson’s disease is marked by a loss of dopamine-producing cells in the brain over time.

The findings, published online in NPG Parkinson’s Disease, could, the researchers say, eventually lead to more effective ways to help people establish and stick with exercise regimens, new treatments for fatigue associated with depression and many other conditions, and a better understanding of Parkinson’s disease.

“Researchers have long been trying to understand why some people find physical effort easier than others,” says study leader Vikram Chib, Ph.D., associate professor in the Department of Biomedical Engineering at the Johns Hopkins University School of Medicine and research scientist at the Kennedy Krieger Institute. “This study’s results suggest that the amount of dopamine availability in the brain is a key factor.”

Chib explains that after a bout of physical activity, people’s perception and self-reports of the effort they expended varies, and also guides their decisions about undertaking future exertions. Previous studies have shown that people with increased dopamine are more willing to exert physical effort for rewards, but the current study focuses on dopamine’s role in people’s self-assessment of effort needed for a physical task, without the promise of a reward.

For the study, Chib and his colleagues from Johns Hopkins Medicine and the Kennedy Krieger Institute recruited 19 adults diagnosed with Parkinson’s disease, a condition in which neurons in the brain that produce dopamine gradually die off, causing unintended and uncontrollable movements such as tremors, fatigue, stiffness and trouble with balance or coordination.

In Chib’s lab, 10 male volunteers and nine female volunteers with an average age of 67 were asked to perform the same physical task — squeezing a hand grip equipped with a sensor on two different days within four weeks of each other. On one of the days, the patients were asked to take their standard, daily synthetic dopamine medication as they normally would. On the other, they were asked not to take their medication for at least 12 hours prior to performing the squeeze test.

On both days, the patients were initially taught to squeeze a grip sensor at various levels of defined effort, and then were asked to squeeze and report how many units of effort they put forth.

When the participants had taken their regular synthetic dopamine medication, their self-assessments of units of effort expended were more accurate than when they hadn’t taken the drug. They also had less variability in their efforts, showing accurate squeezes when the researchers cued them to squeeze at different levels of effort.

In contrast, when the patients hadn’t taken the medication, they consistently over-reported their efforts — meaning they perceived the task to be physically harder — and had significantly more variability among grips after being cued.

In another experiment, the patients were given a choice between a sure option of squeezing with a relatively low amount of effort on the grip sensor or flipping a coin and taking a chance on having to perform either no effort or a very high level of effort. When these volunteers had taken their medication, they were more willing to take a chance on having to perform a higher amount of effort than when they didn’t take their medication.

A third experiment offered participants the choice between getting a small amount of guaranteed money or, with the flip of a coin, getting either nothing or a higher amount of money. Results showed no difference in the subjects on days when they took their medication and when they did not. This result, researchers say, suggests that dopamine’s influence on risk-taking preferences is specific to physical effort-based decision-making.

Together, Chib says, these findings suggest that dopamine level is a critical factor in helping people accurately assess how much effort a physical task requires, which can significantly affect how much effort they’re willing to put forth for future tasks. For example, if someone perceives that a physical task will take an extraordinary amount of effort, they may be less motivated to do it.

Understanding more about the chemistry and biology of motivation could advance ways to motivate exercise and physical therapy regimens, Chib says. In addition, inefficient dopamine signaling could help explain the pervasive fatigue present in conditions such as depression and long COVID, and during cancer treatments. Currently, he and his colleagues are studying dopamine’s role in clinical fatigue.

Source: The Johns Hopkins University

 

 

 

 

Low Testosterone Levels Tied to More Severe COVID in Men

Men with low testosterone levels may be more likely to have more severe illness when infected with COVID-19, according to a new study.

Treating men who have low testosterone with hormone therapy may reduce their risk of serious illness from COVID, researchers said, but it comes with other risks that doctors and patients will need to weigh.

The investigators analyzed the cases of more than 700 men who tested positive for COVID — most before vaccines were available.

Men with low testosterone (low-T) who contracted the virus were 2.4 times more likely to require hospitalization than men with normal hormone levels. But men who had been treated successfully for low-T before catching COVID were not more likely to be hospitalized.

“Low testosterone is very common; up to a third of men over 30 have it,” said study co-author Dr. Abhinav Diwan, a professor at Washington University School of Medicine in St. Louis.

“Our study draws attention to this important risk factor and the need to address it as a strategy to lower [COVID] hospitalizations,” Diwan said in a school news release.

Researchers had previously found that men hospitalized with COVID had abnormally low levels of the male hormone. But they didn’t know whether low-T is a risk factor for severe COVID or a result of it.

For that, they needed to find out whether men with chronically low testosterone levels — before illness or after recovering — were getting sicker than men with normal levels.

From two hospital systems in the St. Louis area, researchers found 723 men with COVID whose testosterone levels were on record. They identified 427 men with normal testosterone levels; 116 with low levels; and 180 who were being successfully treated for low levels.

They had confirmed cases of COVID in 2020 or 2021 and low-T either before or after their infection.

“Low testosterone turned out to be a risk factor for hospitalization from COVID, and treatment of low testosterone helped to negate that risk,” said co-author Dr. Sandeep Dhindsa, an endocrinologist at Saint Louis University.

Dhindsa noted that the risk “really takes off” when levels of testosterone in the blood are below 200 nanograms per deciliter. The normal range is 300 to 1,000.

“This is independent of all other risk factors that we looked at: age, obesity or other health conditions,” Dhindsa said in the release. “But those people who were on therapy, their risk was normal.”

The study suggests, but doesn’t prove, that low testosterone is an independent risk factor for COVID hospitalization, similar to diabetes, heart disease and chronic lung disease. A clinical trial would be needed to prove this link between low-T and severe COVID-19.

Low testosterone levels can cause sexual dysfunction, depressed mood, irritability, difficulty with concentration and memory, fatigue, loss of muscular strength and reduced sense of well-being.

Some doctors treat the condition only if a man’s quality of life is diminished, because testosterone therapy may increase his risk for prostate cancer risk and heart disease.

“In the meantime, our study would suggest that it would be prudent to look at testosterone levels, especially in people who have symptoms of low testosterone, and then individualize care,” said Diwan, a cardiologist. “If they are at really high risk of cardiovascular events, then the doctor could engage the patient in a discussion of the pros and cons of hormone replacement therapy, and perhaps lowering the risk of COVID hospitalization could be on the list of potential benefits.”

The findings were published in JAMA Network Open.

Source: HealthDay

 

 

 

 

For Women, Greater Exposure to Estrogen in Life May Protect Brain Regions That Are Vulnerable to Alzheimer’s

The drop in estrogen levels that occurs with menopause brings declines in the volumes of “gray matter,” the cellular matter of the brain, in key brain regions that are also affected in Alzheimer’s disease. But a new study from Weill Cornell Medicine researchers, in collaboration with the University of Arizona, suggests that greater cumulative exposure to estrogen in life, for example from having had more children or from having taken menopause hormone therapy, may counter this brain-shrinking effect.

The findings, reported in Neurology, come from an analysis of personal histories, MRI scans and cognitive tests on 99 women in their late 40s to late 50s. The researchers confirmed an earlier finding linking menopause to lower gray matter volume (GMV) in brain areas that are also vulnerable to Alzheimer’s. But they also linked indicators of higher overall estrogen exposure, such as a longer span of reproductive years (menarche to menopause), more children and the use of menopause hormone therapy and hormonal contraceptives, to higher GMV in some of these brain areas.

The study was an observational study rather than a clinical trial, but it adds to the evidence that estrogen may have a protective effect on the female brain, limiting the loss of gray matter that normally comes with menopause, and thereby potentially reducing Alzheimer’s risk.

“Our findings suggest that while the menopause transition may bring vulnerability for the female brain, other reproductive history events indicating greater estrogen exposure bring resilience instead,” said study senior author Dr. Lisa Mosconi, an associate professor of neuroscience in neurology at Weill Cornell Medicine and director of the Women’s Brain Initiative, and associate director of the Alzheimer’s Prevention Clinic at Weill Cornell Medicine and NewYork-Presbyterian/Weill Cornell Medical Center.

Researchers estimate that nearly two thirds of those living with Alzheimer’s in the United States are women. The higher prevalence of Alzheimer’s in women may be due in part to women’s greater longevity, among other reasons. A leading hypothesis is that that vulnerability relates to estrogen.

Receptors for estrogen molecules are found in cells throughout women’s brains, and the sex hormone has long been known not just to help steer brain development and behavior but also generally to have a nourishing and protecting role in the central nervous system. That protection doesn’t last forever, though. Estrogen levels decline steeply during the transition through menopause, and as recent research from Dr. Mosconi and others has shown, women tend to experience significant GMV loss during this transition.

The volume loss occurs especially in brain regions that are the most heavily affected in Alzheimer’s, and at roughly the same time of life when the long, slow process of late-onset Alzheimer’s is believed to start. Thus, women’s mid-life loss of estrogen may be a key factor behind the higher risk of Alzheimer’s.

The flip side of this hypothesis is that more estrogen, in particular a cumulatively greater estrogen exposure, could serve as a counter to the brain-weakening effect of menopause. That possibility is what Dr. Mosconi and her team sought to investigate in the new study.

The analysis covered 99 women aged 46-58 and a comparison group of 29 similarly aged men. It confirmed that the post-menopausal and peri-menopausal (starting menopause) women, compared with the pre-menopausal women and the men, had significantly lower GMV—adjusted for age and head size—in brain areas such as the hippocampus, entorhinal cortex and temporal lobe regions, which are heavily affected by Alzheimer’s.

By contrast, among the women, having more estrogen exposure as implied by various factors was associated with greater GMV in certain brain areas. Longer reproductive span, for example, was significantly linked to more GMV in a cluster of regions near the top of the brain including the superior parietal lobule and precuneus of the left hemisphere. Having had more children was significantly associated with more GMV in inferior and middle frontal gyri, and middle and inferior temporal gyri. Having used hormone replacement therapy was associated with more GMV in superior frontal gyrus and several other brain regions. All these brain regions are known to be affected by aging and Alzheimer’s.

The results support the idea that estrogen can be protective, the researchers say, and suggest that further investigation of the specific biological pathways underlying this effect could yield medical or lifestyle changes that help women reduce their risk of cognitive decline with aging as well as Alzheimer’s dementia risk.

“We’re hoping now to get further into the details of these links between estrogen and GMV, for example by comparing the effects of surgical menopause and spontaneous menopause, and by focusing specifically on certain types of estrogen exposure, such as menopause hormone therapy,” said study first author Eva Schelbaum, research assistant in Dr. Mosconi’s laboratory. “The goal as always is to understand why Alzheimer’s affects more women than men, and how we can reduce that risk.”

Source: Weill Cornell Medicine

Elevated Stress Hormones Linked to Higher Risk of High Blood Pressure and Heart Events

Adults with normal blood pressure and high levels of stress hormones were more likely to develop high blood pressure and experience cardiovascular events compared to those who had lower stress hormone levels, according to new research published today in Hypertension, an American Heart Association journal.

Studies have shown that cumulative exposure to daily stressors and exposure to traumatic stress can increase cardiovascular disease risk. A growing body of research refers to the mind-heart-body connection, which suggests a person’s mind can positively or negatively affect cardiovascular health, cardiovascular risk factors and risk for cardiovascular disease events, as well as cardiovascular prognosis over time.

“The stress hormones norepinephrine, epinephrine, dopamine and cortisol can increase with stress from life events, work, relationships, finances and more. And we confirmed that stress is a key factor contributing to the risk of hypertension and cardiovascular events,” said study author Kosuke Inoue, M.D., Ph.D., assistant professor of social epidemiology at Kyoto University in Kyoto, Japan. Inoue also is affiliated with the department of epidemiology at the Fielding School of Public Health at the University of California, Los Angeles.

“Previous research focused on the relationship between stress hormone levels and hypertension or cardiovascular events in patients with existing hypertension. However, studies looking at adults without hypertension were lacking,” Inoue said. “It is important to examine the impact of stress on adults in the general population because it provides new information about whether routine measurement of stress hormones needs to be considered to prevent hypertension and CVD events.”

Study subjects were part of the MESA Stress 1 study, a substudy of the Multi-Ethnic Study of Atherosclerosis (MESA), a large study of atherosclerosis risk factors among more than 6,000 men and women from six U.S. communities. As part of MESA exams 3 and 4 (conducted between July 2004 and October 2006), white, Black and Hispanic participants with normal blood pressure from the New York and Los Angeles sites were invited to participate in the substudy MESA Stress 1. In this substudy, researchers analyzed levels of norepinephrine, epinephrine, dopamine and cortisol – hormones that respond to stress levels. Hormone levels were measured in a 12-hour overnight urine test. The substudy included 412 adults ages 48 to 87 years. About half were female, 54% were Hispanic, 22% were Black and 24% were white.

Participants were followed for three more visits (between September 2005 and June 2018) for development of hypertension and cardiovascular events such as chest pain, the need for an artery-opening procedure, or having a heart attack or stroke.

Norepinephrine, epinephrine and dopamine are molecules known as catecholamines that maintain stability throughout the autonomic nervous system—the system that regulates involuntary body functions such as heart rate, blood pressure and breathing. Cortisol is a steroid hormone released when one experiences stress and is regulated by the hypothalamic-pituitary-adrenal axis, which modulates stress response.

“Although all of these hormones are produced in the adrenal gland, they have different roles and mechanisms to influence the cardiovascular system, so it is important to study their relationship with hypertension and cardiovascular events, individually,” Inoue said.

Their analysis of the relationship between stress hormones and development of atherosclerosis found:

• Over a median of 6.5-year follow-up period, every time the levels of the four stress hormones doubled was associated with a 21-31% increase in the risk of developing hypertension.
• During a median of 11.2-years of follow-up, there was a 90% increased risk of cardiovascular events with each doubling of cortisol levels. There was no association between cardiovascular events and catecholamines.

“It is challenging to study psychosocial stress since it is personal, and its impact varies for each individual. In this research, we used a noninvasive measure — a single urine test — to determine whether such stress might help identify people in need of additional screening to prevent hypertension and possibly cardiovascular events,” Inoue said.

“The next key research question is whether and in which populations increased testing of stress hormones could be helpful. Currently, these hormones are measured only when hypertension with an underlying cause or other related diseases are suspected. However, if additional screening could help prevent hypertension and cardiovascular events, we may want to measure these hormone levels more frequently.”

A limitation of the study is that it did not include people who had hypertension at the study’s start, which would have resulted in a larger study population. Another limitation is that researchers measured stress hormones via a urine test only, and no other tests for stress hormone measurement were used.

Source: American Heart Association