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Roughly half of all adults living in the U.S. have hypertension, with men affected more than women (48 percent versus 43 percent, respectively). However, the sex differences in hypertension prevalence aren’t consistent throughout the lifespan: Women who are 65 and older are more likely to have hypertension than men, raising concerns that current blood pressure recommendations should consider sex. Now, findings from a new study suggest that having an average systolic blood pressure of 160 mm Hg or higher increases the risk of dying from cardiovascular disease (CVD) among women by 113 percent.
Researchers drew on data from more than 53,000 middle-aged adults enrolled in the NHANES studies. Over about ten years, they measured the participants' blood pressures three times and averaged the measures. They also tracked the participants' CVD-related death rates.
They found that links between blood pressure measures and CVD-related deaths differed by sex. Women experience a 61 percent increased risk of cardiovascular death when systolic blood pressure reaches between 130-139 mm Hg, and it soars to 113 percent when at 160 mm Hg or higher. In comparison, men see a 76 percent increased risk only when systolic measures are 160 mm Hg or higher.
When considering diastolic blood pressure, men had a higher risk of dying from CVD if measures were too low (below 70 mm Hg) or too high (80 mm Hg or more), compared to the risk associated with measures between 70 and 80 mm Hg. Again, for women, the risk was higher with diastolic measures that were too low (below 50 mm Hg) or too high (80 mm Hg or higher).
These findings suggest that having high blood pressure markedly increases the risk of death from CVD, and this risk begins at much lower measures among women than men.
Nearly two-thirds of adults in the United States have high blood pressure, defined as having a systolic pressure of 130 mmHg or higher or a diastolic pressure of 80 mmHg or higher. High blood pressure increases a person’s risk for heart disease and stroke and contributes to small vessel disease, a major risk factor for cardiovascular disease, dementia, and stroke. However, lifestyle factors, such as sauna use, help maintain healthy blood pressure. Learn more in this clip featuring Dr. Jari Laukkanen.
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Oral contraceptives influence how women process stress, disrupting the typical hormonal adjustment seen during social interactions. www.sciencedaily.com
Oral contraceptives are widely known for their role in preventing pregnancy, but evidence suggests they also influence the body’s stress response. A recent study shows that women who took oral contraceptives had lower levels of adrenocorticotropic hormone (ACTH), a component of the hypothalamic-pituitary-adrenal axis typically produced in response to stress.
Researchers measured blood ACTH levels in 131 young women before and after the women participated in group activities designed to promote social bonding and reduce stress. The participants completed questionnaires about their moods before and after the activities.
They found that ACTH levels decreased among women not using contraceptives during the stress-buffering group activities, but this effect varied depending on their menstrual cycle phase. However, women using oral contraceptives did not experience the same decrease in ACTH levels during the group activities, regardless of their menstrual cycle phase.
These findings suggest that oral contraceptives not only affect the reproductive system but also influence the body’s response to stress. Learn about other effects of oral contraceptives in this clip from a live Q&A with Dr. Rhonda Patrick.
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Estradiol enhances anti-viral responses in the genital tract of mice infected with herpes simplex virus type 2. (2016) www.sciencedaily.com
From the article:
“If this pathway can be verified in women, then we have laid the foundation to address a number of important public health issues, particularly whether some hormonal contraceptives may be better than others for women who are at higher risk of acquiring sexually transmitted infections, such as in Sub-Saharan Africa, where both HIV-1 and HSV-2 infection rates are high.”
As part of the study, researchers implanted estradiol-releasing pellets into female mice whose ovaries had been removed. The mice then received two rounds of an HSV-2 vaccine, followed by a high dose of the virus.
The researchers saw that the majority of the mice survived and showed less severe disease symptoms, compared to a control group that was not immunized. Further analysis of the molecular pathways underpinning this defensive mechanism revealed that estradiol primes dendritic cells in the vaginal tract to initiate anti-viral T cell immunity.
More specifically, the researchers reported an increase in anti-viral activity unique to the vaginal tract and not found in any other mucosal lining of the body.
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Transdermal estrogen therapy modestly improved sexual function in early postmenopausal women. (2017) www.sciencedaily.com
From the article:
In the new article, Hugh S. Taylor, M.D., of the Yale School of Medicine, New Haven, Conn., and his coauthors report on an ancillary study of a clinical trial that examined changes in sexual function in recently postmenopausal women. The ancillary study included 670 women given oral conjugated equine estrogens (o-CEE), transdermal 17β-estradiol (t-E2) or placebo.
The women ranged in age from 42 to 58 and were within three years of their last menstrual period.
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– The transdermal treatment was associated with moderate improvement in the overall sexual function score across all time points compared with placebo; there was not a significant difference in overall sexual function score with oral estrogen treatment compared with placebo.
– There was no difference in overall sexual function score between the oral and transdermal estrogen therapy on average across four years.
– In specific areas of sexual function, the transdermal treatment was associated with an increase in average lubrication and decreased pain compared with placebo.
– The proportion of women with low sexual function was lower after transdermal treatment compared with placebo; there was no significant reduction in the odds of low sexual function with oral estrogen therapy.
The study has limitations including the restricted generalizability of its findings because the population of the clinical trial was predominantly white women with a higher educational background than the general population.
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Exogenous testosterone can temporarily impair fertility in men by inhibiting sperm cell differentiation. (2015) www.nature.com
From the publication:
Exogenous testosterone considerably impairs spermatogenesis through suppression of the HPG [hypothalamic–pituitary–gonadal] axis, with decreased levels of follicle-stimulating hormone (FSH), luteinizing hormone and intratesticular testosterone. This effect seems to be most frequent or most profound with the use of intramuscular formulations compared with topical agents. The high number of men in their reproductive years who take testosterone, seems to be partly caused by the misconception that testosterone enhances fertility and a lack of knowledge about its contraceptive effects. This misunderstanding is not limited to patients or non-urologists, as 25% of urologists indicate that they would use testosterone for empirical male infertility treatment.
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These studies demonstrate that, in most cases, azoospermia or severe oligospermia will resolve by 4–12 months after cessation of testosterone or other anabolic steroid use.
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Obese teen boys showed up to 50 percent less testosterone than lean boys. (2012) www.sciencedaily.com
From the article:
We were surprised to observe a 50 percent reduction in testosterone in this pediatric study because these obese males were young and were not diabetic,“ says Paresh Dandona, MD, PhD, SUNY Distinguished Professor in the Department of Medicine, chief of the Division of Endocrinology, Diabetes and Metabolism in the UB medical school and first author on the study. "The implications of our findings are, frankly, horrendous because these boys are potentially impotent and infertile,” says Dandona. “The message is a grim one with massive epidemiological implications.”
The small study included 25 obese and 25 lean males and was controlled for age and level of sexual maturity. Concentrations of total and free testosterone and estradiol, an estrogen hormone, were measured in morning fasting blood samples. The results need to be confirmed with a larger number of subjects, Dandona says.
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“The good news is that we know that testosterone levels do return to normal in obese adult males who undergo gastric bypass surgery,” says Dandona. “It’s possible that levels also will return to normal through weight loss as a result of lifestyle change, although this needs to be confirmed by larger studies.”
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A drop in testosterone levels over time is more likely to result from a man’s behavioral and health changes than by aging, study suggests. (2012) www.sciencedaily.com
From the article:
On average, testosterone levels did not decline significantly over five years; rather, they decreased less than 1 percent each year, the authors reported. However, when the investigators analyzed the data by subgroups, they found that certain factors were linked to lower testosterone levels at five years than at the beginning of the study.
“Men who had declines in testosterone were more likely to be those who became obese, had stopped smoking or were depressed at either clinic visit,” Wittert said. “While stopping smoking may be a cause of a slight decrease in testosterone, the benefit of quitting smoking is huge.”
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Unmarried men in the study had greater testosterone reductions than did married men. Wittert attributed this finding to past research showing that married men tend to be healthier and happier than unmarried men. “Also, regular sexual activity tends to increase testosterone,” he explained.
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Restoring testosterone production in men may be as effective as replacing it, without compromising their fertility. (2015) www.sciencedaily.com
From the article:
While testosterone replacement therapy can boost men’s energy levels, sex drive, and mood, the treatment can fool the body into thinking that it is producing enough testosterone, so that it in turn starts making less of its own. This can result in a significant decrease in sperm count–leading to infertility–because the body needs its own testosterone to produce sperm.
An alternative approach to testosterone replacement is based on restoring the body’s natural production of testosterone with drugs similar to those used to help women ovulate. […] compared such a drug, called Enclomiphene citrate, with testosterone replacement therapy (Androgel) in overweight men with low testosterone, or hypogonadism. In the randomized studies, 44 men started on 12.5 mg of oral enclomiphene citrate daily, with 25 men being up-titrated to 25 mg; 42 men received a topical 1.62 percent AndroGel; and 41 men received a placebo. Over five months, patients had 10 clinic visits with one overnight stay.
The investigators found that Enclomiphene citrate restored blood testosterone levels to normal after 16 weeks while maintaining sperm concentrations, whereas Androgel restored blood testosterone levels but caused marked reductions in sperm concentrations by suppressing the function of the testes.
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In a study of men with low testosterone, 56% of study participants suffered from depression or showed depressive symptoms. (2015) www.sciencedaily.com
From the article:
The research, slated to publish online on July 1 in the Journal of Sexual Medicine, involved 200 adult men, aged 20-77, with a mean age of 48 years old, who were referred for borderline total testosterone levels between 200 and 350 ng/dL. Information gathered included demographics, medical histories, medication use, signs and symptoms of hypogonadism, and assessments of depressive symptoms and/or a known diagnosis of depression or use of an antidepressant.
Depression and/or depressive symptoms were present in 56 percent of the subjects. Furthermore, one quarter of the men in the study were taking antidepressants and that the men had high rates of obesity and low rates of physical activity. The most common symptoms were erectile dysfunction, decreased libido, fewer morning erections, low energy, and sleep disturbances.
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Testosterone therapy may boost sexual function and mood in older men with low testosterone levels. (2016) www.sciencedaily.com
From the article:
Yale enrolled the largest number of participants at any one site (84 of 790) for these double-blind, placebo-controlled trials that investigated the efficacy of testosterone gel for multiple outcomes, including sexual function, physical function, and vitality.
The researchers found that men who received testosterone therapy for one year, versus those on placebo, saw significant improvements in sexual function, including sexual activity, sexual desire, and erectile function.
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While participants enrolled in the trial that assessed physical function did not see significant improvements in their walking ability – as measured by an increase of 50 meters or more in their distance walked in 6 minutes – an increase was found when all study participants were evaluated. In addition, men enrolled in the vitality trial saw modest benefits in terms of improved mood and fewer depressive symptoms.
While the results were somewhat mixed, Gill noted an overall benefit that had not been seen in previous studies. “One way of interpreting the results across trials is a global impression of change,” he said. “We found that testosterone improved men’s impression that their sexual desire, walking ability, energy level, and overall health were better.”
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Testosterone administration to deficient older men did not affect atherosclerosis rates, sexual function, or health-related quality of life. (2015) www.sciencedaily.com
From the article:
Shalender Bhasin, M.B.B.S., of Brigham and Women’s Hospital, Harvard Medical School, Boston, and colleagues randomly assigned 308 men 60 years or older with low or low-normal testosterone levels to receive 7.5 g of 1 percent testosterone (n = 156) or placebo (n = 152) gel packets daily for 3 years. The dose was adjusted to achieve testosterone levels between 500 and 900 ng/dL. Characteristics were similar between groups at study entry: patients were an average age of 68 years; 42 percent had hypertension; 15 percent, diabetes; 15 percent, cardiovascular disease; and 27 percent, obesity.
The researchers found that the rates of subclinical atherosclerosis progression, as measured by changes in common carotid artery intima-media thickness or coronary artery calcium, did not differ significantly between men assigned to the testosterone or placebo groups. Changes in intima-media thickness or calcium scores were not associated with change in testosterone levels among individuals assigned to receive testosterone.
Sexual desire, erectile function, overall sexual function scores, partner intimacy, and health-related quality of life did not differ significantly between groups. Hematocrit (a measure of red blood cells) and prostate-specific antigen levels increased more in testosterone group.
The authors write that this trial was not designed to determine the effects of testosterone on CVD events, and that a substantially larger trial would be needed to determine this.
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Decreased sexual activity and desire may cause a decline in serum testosterone of less than 10% in older men. (2015) www.sciencedaily.com
From the article:
Whether decreasing sexual function is a cause or an effect of reduced androgen status in older men, or whether some other age-related factor may be involved, is not clear.
[…]
At both visits, the participants answered questions about their sexual functions, including, “How often are you able to get and keep an erection that is firm enough for satisfactory sexual activity?”; “How many times over the last month have you had sexual activity (including intercourse and masturbation) reaching ejaculation?”; and, “How much desire for sex do you have now, compared with when you were 50?”
[…]
Over two years, baseline serum testosterone, DHT, E2 and E1 did not predict decline in sexual activity, sexual desire and erectile function. By contrast, the decline in testosterone (but not in DHT, E2 or E1) over time, though less than 10%, was strongly related to decreased sexual activity and desire, but not to erectile dysfunction.
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In symptomatic older men with low testosterone, testosterone therapy resulted in sustained improvement in most types of sexual activity. (2016) www.sciencedaily.com
From the article:
The placebo-controlled, double-blinded trial examined the effect of testosterone therapy on sexual function in a group of 470 men. The men were enrolled in the study through 12 academic medical centers. The participants were at least 65 years old and had low testosterone levels, based on the average results of multiple tests. All of the men had a heterosexual partner.
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The men treated with testosterone therapy displayed consistent improvement in libido and in 10 of the 12 sexual activity measurements, including frequency of intercourse, masturbation and nighttime erections. In comparison, men who received the placebo did not change their questionnaire responses significantly over the course of the year-long study.
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Exercising, drinking coffee and having sex are triggers that raise rupture risks for brain aneurysm, retrospective study finds. (2011) www.sciencedaily.com
From the article:
Calculating population attributable risk – the fraction of subarachnoid hemorrhages that can be attributed to a particular trigger factor – the researchers identified the eight factors and their contribution to the risk as:
-Coffee consumption (10.6 percent)
-Vigorous physical exercise (7.9 percent)
-Nose blowing (5.4 percent)
-Sexual intercourse (4.3 percent)
-Straining to defecate (3.6 percent)
-Cola consumption (3.5 percent)
-Being startled (2.7 percent)
-Being angry (1.3 percent)
“All of the triggers induce a sudden and short increase in blood pressure, which seems a possible common cause for aneurysmal rupture,” said Monique H.M. Vlak, M.D., lead author of the study and a neurologist at the University Medical Center in Utrecht, the Netherlands.
Risk was higher shortly after drinking alcohol, but decreased quickly, researchers said.
[…]
Although physical activity had triggering potential, researchers don’t advise refraining from it because it’s also an important factor in lowering risk of other cardiovascular diseases.
“Reducing caffeine consumption or treating constipated patients with unruptured IAs with laxatives may lower the risk of subarachnoid hemorrhage,” Vlak said. “Whether prescribing antihypertensive drugs to patients with unruptured IAs is beneficial in terms of preventing aneurysmal rupture still needs to be further investigated.”
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Painkillers in pregnancy may affect baby's future fertility: evidence from animal models www.sciencedaily.com
From the article:
Human tissues exposed to either drug for one week in a dish had reduced numbers of cells that give rise to sperm and eggs, called germ cells, the study found.
Ovaries exposed to paracetamol for one week had more than 40 per cent fewer egg-producing cells. After ibuprofen exposure, the number of cells was almost halved.
Experts say this is important because girls produce all of their eggs in the womb, so if they are born with a reduced number it could lead to an early menopause.
Painkiller exposure during development could have effects on unborn boys too, the study found. Testicular tissue exposed to painkillers in a culture dish had around a quarter fewer sperm-producing cells after exposure to paracetamol or ibuprofen.
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Seven days of exposure to acetominophen reduced testosterone by 45% in mouse model of in utero testicular development www.sciencedaily.com
From the article:
The University of Edinburgh study tested the effect of paracetamol on testosterone production in mice that carried grafts of human testicular tissue. These grafts have been shown to mimic how the developing testes grow and function during pregnancy.
Scientists gave the mice a typical daily dose of paracetamol – over a period of either 24 hours or seven days. They measured the amount of testosterone produced by the human tissue an hour after the final dose of paracetamol.
They found there was no effect on testosterone production following 24 hours of paracetamol treatment. After seven days of exposure, however, the amount of testosterone was reduced by 45 per cent.
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12-week exercise program of 40-60 minutes of jogging three days per week significantly improved testosterone and systolic b.p. in overweight men www.sciencedaily.com
40-60 minutes 3x per week:
- Systolic blood pressure: 134 ± 4 vs. 119 ± 3 (after)
- Diastolic blood pressure: 85 ± 2 vs. 75 ± 1 (after)
From the article:
At baseline, the overweight/obese men had significantly lower total, free and bioavailable testosterone level than normal weight men. All of the study volunteers completed a 12-week aerobic exercise plan that entailed 40-60 minutes of walking or jogging on one to three days per week.
[…]
I think decrease in body mass is one of the factors for increasing serum testosterone levels,“ said Hiroshi Kumagai, lead researcher on the study. "However, the degree of weight loss is small, and we found that the increase in vigorous physical activity was independently associated with the increase in serum testosterone levels. So, it seems the increase in physical activity, especially vigorous physical activity, is the main factor for increasing serum testosterone levels.”
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Chimerism is a condition in which a person’s body contains two different sets of DNA. It can occur in fraternal twins and as a consequence of bone marrow transplantation. A recent news article describes a unique case of chimerism that could have implications for forensic scientists.
Three months after a man received a bone marrow transplant to treat his acute myeloid leukemia, some tissue samples from his body contained two sets of DNA: his own, and that of the donor. Other tissues had only the recipient’s DNA. Remarkably, the changes in the man’s DNA persisted for several years, and now, some four years after the bone marrow transplant, the DNA in his semen is exclusively that of the donor.
This case could have serious implications for the field of forensic science, especially when investigating sex crimes. For example, if an individual developed chimerism following a bone marrow transplant and then went on to commit a crime, it could mislead forensic investigators.