Degenerative Brain Disease Found In 87% of Former Football Players: Study

The link between football and traumatic brain injury continues to strengthen. Now, one of the largest studies on the subject to date finds that 110 out of 111 deceased NFL players had chronic traumatic encephalopathy (CTE), a degenerative brain disorder associated with repetitive head trauma.

Several studies have linked CTE to suicidal behavior, dementia and declines in memory, executive function and mood. Professional athletes may be at higher risk for CTE because of their high likelihood for concussions and other traumatic brain injuries; up to 3.8 million sports-related concussions occur in the United States each year. In 2016, a health official with the NFL acknowledged the link between football and CTE for the first time.

In the new study, published in the Journal of the American Medical Association, researchers looked at the brains of 202 deceased people who had played football at various levels, from high school to the NFL. (The brains had been donated to a brain bank at Boston University for further study.) The researchers analyzed the brains for signs of CTE and also spoke to family members about the players’ histories.

They diagnosed CTE in 87% of the players. Among the 111 NFL players, 99% had CTE.

“This study more than doubles the number of cases reported in the literature of CTE,” says study author Dr. Jesse Mez, an assistant professor of neurology at Boston University School of Medicine. “It suggests, with a lot of caveats, that this is probably not a rare disease—at least among those who are exposed to a lot of football.”

The severity of CTE symptoms appeared to progress the more a person played the sport. High school players included in the study tended to have mild disease, and most college, semi-professional and professional players had severe symptoms. The study authors also found that mood, behavior and cognition problems were common among the players with mild to severe CTE.

Among players with severe CTE, 85% had signs of dementia, and 89% had behavioral or mood symptoms, or both. They were also likely to have issues in brain regions associated with depressive symptoms, impulsivity and anxiety. 95% had cognitive symptoms, like issues with memory, executive function and attention.

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The study has key limitations. Researchers studied a limited and possibly skewed sample of brains; news about repetitive head trauma and CTE has become increasingly prevalent, and families of players with symptoms of brain injury may have felt more motivated to participate in the brain bank study. It’s also still difficult to say how common CTE is among all football players.

“The numbers are not meant to represent the prevalence of CTE in football players,” says Mez. “But it does begin to suggest a relationship between football and this disease, and that’s an important step for research that will look at this in the future.”

Mez says the brain bank, which is ongoing, receives between 50 to 100 donations every year. Having access to brain tissue allows the researchers to study possible mechanisms for CTE, and why some players develop it while others do not. “We are really early in understanding this disease,” says Mez.

7 Ways to Keep Your Brain Sharp As You Age

There’s mounting evidence that some of the best things you can do for your brain are also some of the best for your body.

A new scientific advisory from the American Heart Association and American Stroke Association, published in the journal Stroke, promotes seven simple steps people can take to keep their brains healthy and reduce their risk of cognitive decline as they get older.

The steps include managing blood pressure, controlling cholesterol, keeping blood sugar normal, getting physically active, eating a healthy diet, losing extra weight and quitting (or never starting) smoking.

These steps also help prevent heart disease and stroke, and that’s no coincidence. In recent years, research findings have become strong enough to recommend these steps—typically recommended to help hearts and lungs—for brain health, as well, say the report’s authors. “In the 1990s we began to notice that the traditional cardiovascular risk factors were not only related to stroke and heart attack and other cardiovascular disease, but they may also be precursors of cognitive impairment,” says vascular neurologist Dr. Philip Gorelick, chair of the advisory’s writing group.

(Bonus: The same seven steps also reduce cancer risk and help protect your kidneys.)

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Research in the early 2000s first linked cardiovascular risk factors like clogged arteries to Alzheimer’s disease, says Gorelick, and an Institute of Medicine (IOM) paper in 2015 touted heart-healthy strategies, like managing high blood pressure and diabetes, as important ways to reduce the risk of cognitive decline.

“Once the IOM released its report, we decided it was time to more forward and think more seriously about advocating for brain health along with heart health,” says Gorelick. The advisory group reviewed 182 published studies while writing their recommendations.

The brain needs adequate blood flow to function optimally, and when blood flow is slowed or blocked—because the heart isn’t pumping properly or the arteries are filled with plaque—brain tissue can become damaged, Gorelick says. Elevated blood pressure, cholesterol and blood sugar can all impair blood vessels leading to the brain and can cause strokes or mini-strokes that can lead to subsequent cognitive decline, called vascular dementia.

But studies show that following these seven steps can help people maintain a healthy brain—defined in the report as one that can pay attention, receive and recognize information from the senses, learn and remember, communicate, solve problems, make decisions, support mobility and regulate emotions. Staring as early as possible is also key, say the advisory authors, since narrowing of the arteries can begin in childhood.

More research is still needed to further define optimal brain health as people age and to determine the best combination of lifestyle and medical strategies to help achieve it. The advisory authors also stress that traditional brain-boosting activities—like continuing education and social interactions throughout life—are still important for mental health.

“Alzheimer’s disease has traditionally been thought of as a so-called neurodegenerative disorder, and people don’t usually associate heart health with it,” he says. “Now when a patient comes into the office, we can tell them with good authority that by controlling cardiovascular risk factors, we can reduce your risk of stroke and heart attack—but we may also be able to help preserve your cognition, as well.”

5 Ways Being Tall Affects Your Health

Being tall might get you a spot on the basketball team, and it may even be good for your self-esteem and your paycheck. But recent research has also found that towering over your peers may affect various aspects of your physical health, as well—and not all for the better.

Some of these health risks have to do with the physiology of being an especially small or large person, and what that means for the body’s organs. Here are a few ways height has recently been linked to health.

More blood clots

In a September study published in the journal Circulation: Cardiovascular Genetics, researchers investigated the link between height and venous thromboembolism, the third leading cause of heart attack and stroke. They found that, in a group of more than 2 million Swedish siblings, men shorter than 5’3” had a 65% lower risk of developing a venous thromboembolism, a type of blood clot that starts in a vein, than men taller than 6’2”. They also analyzed a group of pregnant women, since pregnancy can be a trigger for these types of blood clots. Those shorter than 5’1” had a 69% lower risk compared to those 6’ and taller.

Why? Gravity may be influencing the link. “It could just be that because taller individuals have longer leg veins there is more surface area where problems can occur,” said lead researcher Dr. Bengt Zöller, associate professor at Lund University and Malmö University Hospital in Sweden, in a news release. Increased gravitational pressure in the veins of taller legs can also increase the risk of blood flow slowing or stopping temporarily.

The CDC estimates that thromboembolisms affect up to 600,000 Americans every year, and that number is increasing—possibly because average height is also increasing, says Zöller.

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Higher risk of dying from cancer

The risk of dying from cancer increases by 4% for every two and a half inches of height a person has, according to a 2016 review paper published in the Lancet Diabetes & Endocrinology. Being tall may be a marker of over-nutrition—specifically, eating too many high-calorie animal proteins—during different stages of growth and development, either throughout life or before birth. That could activate growth processes that leave cells vulnerable to mutations, the report states.

There are other theories, as well. “Height may also be an indicator of organ size,” wrote review co-author Matthias Schulze of the German Institute of Human Nutrition in an email to TIME. “The larger the organ, the more cells are at risk of malignant transformation.”

Other studies have also found that tall (and obese) men are at increased risk of developing aggressive forms of prostate cancer, and that tall women are more likely to develop melanoma, as well as breast, ovarian, endometrial and colon cancer.

Less heart disease and diabetes

On the other hand, tall people may have have lower rates of heart disease and diabetes. In the recent Lancet study, for every 2.5 inches of height, a person’s risk of dying from heart disease decreased by 6%. Taller people tend to naturally have bigger lungs and stronger hearts, says Schulze, which may partially explain these effects. Plus, the same over-nutrition phenomenon associated with increased cancer risk may be protective in other ways: It could trigger an increased production of a hormone that helps the body control blood sugar and cholesterol levels.

Higher risk of a-fib

There may be another exception to the taller-is-heart-healthier rule. Preliminary research presented at a cardiology conference in April found that taller and bigger women are nearly three times as likely to develop atrial fibrillation, a dangerous heart rhythm disorder.

The larger a woman’s body size as a young adult, the more likely she was to develop the irregularity during the 16-year study. Larger cells in a woman’s heart could interrupt its electrical pathways, the authors suspect, and extra pressure against the lungs (due to a woman’s large size) could cause the heart to distend.

However, the potential effects of height on disease and mortality risk are still likely very low, say the experts—certainly lower than the risk factors you can control, like diet, exercise, smoking and drinking alcohol.

Here’s What Every Organ in the Body Would Cost to Transplant

It’s one thing to say that organ transplants are hard to come by. It’s another thing to consider that a intestinal transplant costs $1,147,300 on average.

Consulting firm Milliman tallies the average costs of different organ transplants in the U.S. And while most are expensive—some are very expensive. A kidney transplant runs just over $400,000. The cost for the average heart transplant, on the other hand, can approach $1.4 million.

Cost is only part of the problem though. Even if the U.S. healthcare system and individual patients are able to pay, availability is extremely limited. More than 116,000 Americans are waiting to receive a transplant, and about 20 die each day during the wait.

New breakthroughs, though, could reduce both wait times and expenses. This summer researchers made strides on processes that could eventually allow pig organs (with are biologically similar to ours) to be transplanted in humans, which would theoretically radically increase availability and decrease cost. Some researchers estimate that such transplants could be available within two years.

Asthma Puffer Med Salbutamol Cuts Parkinson’s Risk By Half

Norwegian researchers have found that using a common asthma medicine cuts in half the likelihood of developing Parkinson’s disease.

The scientists examined data from more than 100 million prescriptions and studied the effects of 1,126 different medicines over that last 11 years in Norway. They were looking to see which compounds might impact levels of the α-synuclein gene in neuroblastoma cells. α-synuclein is a protein that collects in the brains of people with Parkinson’s and forms clumps thoughts to impact motor function.

The drug screening turned up four molecules that had an impact. Three of these were asthma medicines that target the β2-adrenoreceptor (β2AR). And one of these lowered levels of the of the α-synuclein gene in the Parkinson’s impacted parts of the brain.

“Our analysis of data from the whole Norwegian population has been decisive for the conclusion in this study,” says Professor Trond Riise, who leads the study. The Norwegian research came after Harvard scientists had earlier found similar effects in animal tests and in lab experiments on brain cells.

“We analysed the whole Norwegian population and found the same results as in the animal testing at Harvard University,” Riise said. “These medicines have never been studied in relation to Parkinson’s disease.”

Riise and team looked at medical records of more than 4 million people in Norway between 2004 and 2014and discovered those taking salbutamol (also known as albuterol) had a far lower likelihood of developing Parkinson’s. Conversely, they found people on propranolol, a drug for treating high blood pressure that turns off β2AR, had double the risk.

The insights could prove a boon to Parkinson’s researchers and clinicians as despite its prevalence, few good treatments (let alone a cure) exist for the debilitating condition. “Our discoveries may be the start of a totally new possible treatment for this serious disease,” Riise said. “We expect that clinical studies will follow these discoveries.”

Little Known Theory Could Hold Key To Sporting Success

An established but little known psychological theory is likely to improve performances across a range of activities, including sport, according to new research published today.

Perceptual Control Theory can be applied to amateurs or skilled performers alike says psychologist Dr Warren Mansell, from The University of Manchester.

The theory argues that when trying to improve performance, teaching people what to do is less effective than teaching them how to picture the outcome.

It has been already been used to accurately model the skills necessary for fielders to get to the right location on the pitch to catch a ball, such as in baseball or cricket.

But according to Dr Mansell, it could be used across sport and the performing arts.

To test the theory, the 48 participants in Dr Mansell’s study were asked to draw images using different instructions.

The images ranged from complex to simple symbols and participants were asked to either copy them directly, copy from memory, or copy by giving instructions on how to move the pen. They were also told draw the image after being told what it looked like.

Describing the image led to significantly more accurate drawings than giving the instructions for what movements to make.

He said: “We commonly instruct people in terms of the physical actions they must carry out in order to perform any task.

“Our study – which we think is the first of its kind – tests the effect of describing how to perform a skill in terms of the perception of the outcome compared to the observable actions.

“And the results were fascinating: the accuracy of the drawings where participants were told what to perceive was almost as good as copying the image directly.”

The theory could also be applied to dance, says Dr Mansell: learning a complex routine is all about an internal sense of where it feels right, rather than obsessing on movements, he argues.

He added: “There is a physiological explanation to this: muscle groups interfere with each other by contracting against another when performing a variety of tasks – whether that’s drawing, dancing or catching a ball.

“So you may not be able to accurately instruct your limbs what to do, but creating a mental picture of the desired outcome gets around that in efficient manner.

Carla Brown-Ojeda, the student who conducted the study, explained: “Different coaches in sport use a wide array of methods, some of which involve the coach directly instructing the learner how to move. Yet if our research generalises, then a simpler, purely ‘perceptual’, method might be developed.”

New Study Links Exercise To Better Self-Control

Research appearing recently in the peer-reviewed journal Behavior Modification shows people engaged in a tailored physical activity intervention demonstrate improved self-control.

“There’s a particular type of task called ‘delay discounting’ that presents individuals with a series of choices between ‘smaller/sooner’ and ‘larger/later’ rewards,” said Michael Sofis, a doctoral student in applied behavioral science at the University of Kansas, who headed the study. “It’s something we all experience in our lives. Do you want a little money now — or wait and get a lot of money later? The degree to which one chooses that smaller/sooner reward is called impulsivity, and that has been linked to obesity problems, gambling and most forms of substance abuse.”

According to Sofis, a change in one’s ability to value future events might keep maladaptive behavior in check and increase the likelihood of making healthy choices. He designed a pilot study, and a subsequent larger study, to see if exercise could trigger changes in delay discounting.

“There’s a lot of neuroscientific evidence that suggests mood-altering effects of physical activity could change how you make decisions,” said Sofis. “There are a variety of proposed biological and neurological mechanisms and different effects for people with different genetic profiles linked to mental health issues. Studies say if I have a genetic profile linked to higher rates of depression and anxiety, I’m more likely to get benefits from physical activity.”

Sofis and KU co-authors Ale Carrillo and David Jarmolowicz recruited participants and instructed them to walk, jog or run laps on a track at “individualized high and low effort levels” and recorded participants’ own perceived effort.

“We wanted to create an individualized, but still standardized approach,” Sofis said. “We had people rate their perceived effort on a scale of six to 20. Six would be just sitting on a couch — and 20 would be maximal exertion. We’d start them at levels of eight and 10, respectively. The idea is that we’d slowly shape them up to higher effort levels. For each person, the amount that they’re exerting is going to relate to amount they’re going to enjoy it.”

Participants’ perceived exertion was established before the study to establish a baseline measure, treatment was tracked for seven to eight weeks, and participants were also asked to self-report maintenance of increased exercise for an additional month. Delay discounting was tested before, during and after treatment, and during maintenance using a standardized 27-item delay discounting task called the Monetary Choice Questionnaire.

The researchers found statistically significant improvements in delay discounting were evident not only during the treatment phase of increased exertion but also that improvements were maintained a month afterward for the group.

“Our study is the first, to our knowledge, that shows maintained changes in delay discounting at follow-up,” Sofis said. “In our study, 13 of 16 participants kept their improved self-control.”

Sofis said the research helps strengthen emerging evidence that delay discounting can be altered. Due to links between discounting and many clinical issues, Sofis suggested that researchers and clinicians alike should attend to discounting as a treatment target.

“This is becoming important as a clinical treatment target,” he said. “If you could measure one outcome and potentially see a change, you should be able to see myriad other changes at once.”

For people showing problems with impulsivity or self-control, Sofis said the takeaway message is simple: Exercise could help.

“I had people of all different ages, BMIs, incomes and mental-health levels, and these studies suggested that nearly every single person at least improved their delayed discounting to some degree,” he said. “If anyone just exercises, it’s likely you will show some improvements. More evidence is needed to draw definitive conclusions, but it’s very encouraging to see people improving. Just show up and give it a go — it seems like people do improve. The encouraging part is we had individuals that were walking the whole time, people in their 50s or 60s, and people in their 20s who were very fit and running, it didn’t seem to matter. Nearly everyone did improve.”

Currently, Sofis is developing a smartphone application, dubbed “Your620,” allowing people to record exercise and delay-discounting changes, and hopes to hear from people interested in the app. He plans to earn his doctoral degree in May from KU, then look for postdoctoral research opportunities where he can perform further research on delay discounting.

Oregon’s Legalization Quickly Cut Washington Border Pot Sales

When Oregon’s recreational sales of marijuana took effect, retail sales in Washington counties across the Columbia River dropped 41 percent in just three days, UO researchers report.

Also taking a dip was the amount of legally sold marijuana leaving Washington, UO economists Benjamin Hansen, Keaton Miller and Caroline Weber noted in their findings, which were published online this week in the working paper series of the National Bureau of Economic Research.

“We found that the majority of marijuana sold in Washington is actually staying there,” said Hansen, the UO’s W.E. Miner Professor of Economics. “We found that prior to Oregon’s legalization 11.9 percent was potentially being diverted out of Washington overall, and it dropped to 7.5 percent after Oregon’s legalization.”

Washington was one of the first states to legalize recreational marijuana. Its stringent regulatory and tracking requirements from production through sales provided a wealth of data, Weber said.

The UO team studied Washington’s sales for two months before and after Oregon’s legal market opened on Oct. 1, 2015. The research, Weber said, captured a naturally occurring experiment as neighboring states implemented recreational marijuana markets.

While the study suggests that the illegal cross-border movement, or diversion, of legally produced marijuana across state borders is a concern, it is not occurring at alarming levels, Hansen said.

That concern, however, was one reason for the study.

In 2013, then-Deputy Attorney General James M. Cole, in what is known as the Cole Memorandum, advised federal law enforcement officials to monitor cross-border movements of the drug, which under federal law is classified as illegal alongside heroin and methamphetamines. The Trump administration has signaled a possible federal crackdown.

“Our study says that 93 percent of marijuana sold in Washington is probably staying there now,” Hansen said. “There’s probably not a lot you can do about the remaining share that is being diverted at this point. This is just the likely consequence of partial prohibition.”

The study also addressed the potential for randomized traffic searches along state borders to stop cross-border transport of marijuana.

Just before Oregon’s market opened, 1,662 retail sales transactions occurred daily in Washington’s Clark and Klickitat counties, just across the river from Portland. Given that 293,840 vehicles traveled between Oregon and those counties daily in 2015, based on Oregon Department of Transportation records, “a policy of randomly searching border-crossing vehicles could expect to find diverted recreational marijuana in just 0.47 percent of stops,” the UO researchers wrote.

“You might expect larger diversion when states around a legalized one are not allowing recreational or medical market sales,” Hansen said.

The team’s analysis determined that randomized searches along Washington’s Spokane and Whitman counties with Idaho, where marijuana is illegal, might yield illegally transported marijuana at most 4 percent of the time.

Based on the study, Hansen said, California likely faces far less diversion because all neighboring states allow for some form of legal marijuana use. Small amounts of illegal, small-scale trafficking are to be expected as long as the U.S. does not have uniform policies, he said.

In the two months prior to the opening of Oregon’s recreational market, 5,624 kilograms (12,398 pounds) of marijuana were sold in Washington; 670 kilograms (1,477 pounds), or 11.9 percent, went across state lines. Factoring in the drop in sales after Oregon’s legalization and no decline seen elsewhere in Washington implies that only 7.5 percent of sales are illegally leaving Washington today, the research team concluded.

“We’ve been able to study this natural experiment to speak to a question that a lot of people in law enforcement and government care about,” Weber said. “If we had instead found that 60 percent of Washington’s marijuana was being diverted, then it would have suggested a whole different approach to thinking about legalization moving forward.”

People seem to prefer purchasing marijuana in legal recreational markets instead of through the black market or as medical marijuana or growing their own, Hansen said.

Zika Virus Selectively Infects And Kills Glioblastoma Cells In Mice

The Zika virus (ZIKV) may infect and kill a specific type of brain cancer cells while leaving normal adult brain tissue minimally affected, according to a new study supported by the National Institute of Allergy and Infectious Diseases (NIAID), a part of the National Institutes of Health. In the paper, published online on September 5 in The Journal of Experimental Medicine, researchers describe the impact of ZIKV on glioblastoma cells in both human tissue samples and mice.

Even with current treatments, patients with glioblastomas — a highly malignant type of brain tumor — tend to have poor survival rates. Glioblastomas grow aggressively from a mass of unspecialized cells; ZIKV is known to infect similar cells in the nervous systems of developing fetuses. A fetus that acquires the virus from its ZIKV-infected mother during pregnancy can develop microcephaly and other serious abnormalities.

In this laboratory study, researchers at the University of California San Diego School of Medicine, the Cleveland Clinic, the Washington University School of Medicine in St. Louis, and the University of Texas Medical Branch in Galveston introduced ZIKV to glioblastoma tissue samples removed from cancer patients as part of their treatment, as well as to healthy human neural tissue cultures. After seven days, the researchers found that ZIKV had replicated in certain glioblastoma cells and prevented them from multiplying, while the ordinary neural tissue cultures remained largely uninfected. The researchers also tested mice with glioblastomas, treating an experimental group with a mouse-adapted strain of ZIKV. Mice who received ZIKV survived longer than mice in the control group, and their tumors were significantly smaller than those in the control mice after one week.

When New Fathers Get Depressed

Postpartum depression is often associated with mothers, but a new study shows that fathers face a higher risk of experiencing it if their testosterone levels are low nine months after their children are born.

The same study revealed that a father’s low testosterone may also affect his partner — but in an unexpectedly positive way. Women whose partners had lower levels of testosterone postpartum reported fewer symptoms of depression themselves nine and 15 months after birth.

High testosterone levels had the opposite effect. Fathers whose levels were high faced a greater risk of experiencing stress due to parenting and a greater risk of acting hostile — such as showing emotional, verbal or physical aggression — toward their partners.

The study, published in the journal Hormones and Behavior, supports earlier studies that show men have biological responses to fatherhood, said Darby Saxbe, the study’s lead author and an assistant professor of psychology at the USC Dornsife College of Letters, Arts and Sciences.

“We often think of motherhood as biologically driven because many mothers have biological connections to their babies through breastfeeding and pregnancy,” Saxbe said. “We don’t usually think of fatherhood in the same biological terms. We are still figuring out the biology of what makes dads tick.

“We know that fathers contribute a lot to child-rearing and that on the whole, kids do better if they are raised in households with a father present,” she added. “So, it is important to figure out how to support fathers and what factors explain why some fathers are very involved in raising their children while some are absent.”

Saxbe worked with a team of researchers from USC, UCLA and Northwestern University.

A snapshot of paternal postpartum depression

For the study, the researchers examined data from 149 couples in the Community Child Health Research Network. The study by the National Institute for Child Health and Human Development involves sites across the country, but the data for this study came from Lake County, Ill., north of Chicago.

Mothers in the study were 18 to 40 years old; African-American, white or Latina; and low-income. They were recruited when they gave birth to their first, second or third child. Mothers could invite the baby’s father to participate in the study as well. Of the fathers who participated and provided testosterone data, 95 percent were living with the mothers.

Interviewers visited couples three times in the first two years after birth: around two months after the child was born, about nine months after birth and about 15 months after birth.

At the nine-month visit, researchers gave the fathers saliva sample kits. Dads took samples three times a day — morning, midday and evening — to monitor their testosterone levels.

Participants responded to questions about depressive symptoms based on a widely used measure, the Edinburgh Postnatal Depression. They also reported on their relationship satisfaction, parenting stress and whether they were experiencing any intimate partner aggression. Higher scores on those measures signaled greater depression, more stress, more dissatisfaction and greater aggression.

Testosterone swings the pendulum

Relatively few participants — fathers and mothers — were identified as clinically depressed, which is typical of a community sample that reflects the general population. Instead of using clinical diagnoses, the researchers looked at the number of depressive symptoms endorsed by each participant.

Men’s testosterone levels were linked with both their own and their partners’ depressive symptoms, but in opposing directions for men and for women.

For example, lower testosterone was associated with more symptoms in dads, but fewer symptoms in moms. The link between their partners’ testosterone levels and their own depression was mediated by relationship satisfaction. If they were paired with lower-testosterone partners, women reported greater satisfaction with their relationship, which in turn helped reduce their depressive symptoms.

“It may be that the fathers with lower testosterone were spending more time caring for the baby or that they had hormone profiles that were more synced up with mothers,” she said. “For mothers, we know that social support buffers the risk of postpartum depression.”

Fathers with higher testosterone levels reported more parenting stress, and their partners reported more relationship aggression.

To measure parenting stress, parents were asked how strongly they related to a set of 36 items from the Parenting Stress Index-Short Form. They responded to statements such as “I feel trapped by my responsibilities as a parent” and “My child makes more demands on me than most children.” A high number of “yes” responses signaled stress.

Relationship satisfaction questions were based on another widely used tool, the Dyadic Adjustment Scale. Parents responded to 32 items inquiring about their relationship satisfaction, including areas of disagreement or their degree of closeness and affection. Higher scores signaled greater dissatisfaction.

Mothers also answered questions from another scientific questionnaire, the HITS (Hurts, Insults, and Threats Scale), reporting whether they had experienced any physical hurt, insult, threats and screaming over the past year. They also were asked if their partners restricted activities such as spending money, visiting family or friends or going places that they needed to go.

“Those are risk factors that can contribute to depression over the long term,” Saxbe said.

Treating fathers with postpartum depression

Although doctors may try to address postpartum depression in fathers by providing testosterone supplements, Saxbe said that the study’s findings indicate a boost could worsen the family’s stress.

“One takeaway from this study is that supplementing is not a good idea for treating fathers with postpartum depression,” she said. “Low testosterone during the postpartum period may be a normal and natural adaptation to parenthood.”

She said studies have shown that physical fitness and adequate sleep can improve both mood and help balance hormone levels.

In addition, both mothers and fathers should be aware of the signs of postpartum depression and be willing to seek support and care, Saxbe said. Talk therapy can help dads — or moms — gain insight into their emotions and find better strategies for managing their moods.