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It’s a ranking that no country would want to have: A new study shows America has taken the lead in drug overdose deaths, with rates almost four times higher than in 17 other wealthy nations.

Drug overdose deaths in the United States have more than tripled over the past 20 years, driven largely by the opioid epidemic, the researchers noted.

Drug overdose epidemic

In 2017, more than 70 000 Americans died from drug overdoses. According to the National Safety Council, more Americans are likely to die from an opioid overdose than a car crash.

“The United States is experiencing a drug overdose epidemic of unprecedented magnitude, not only judging by its own history, but also compared to the experiences of other high-income countries,” said study author Jessica Ho. She’s an assistant professor at the University of Southern California’s Leonard Davis School of Gerontology.

“For over a decade now, the United States has had the highest drug overdose mortality among its peer countries,” Ho said in a university news release.

In fact, drug deaths in the United States are more than 27 times higher than in Italy and Japan, which have the lowest rates, and are double the rates of Finland and Sweden, the countries with the next highest death rates.

Drug overdose deaths have also affected life expectancy. In 2013, drug overdoses made up 12% of the life expectancy gap among men and 8% among women between the United States and other high-income countries.

Commercial hyping of painkiller

If it weren’t for drug overdose deaths, the life expectancy gap would have been much smaller between 2003 and 2013, the researchers added.

“On average, Americans are living 2.6 fewer years than people in other high-income countries. This puts the United States more than a decade behind the life expectancy levels achieved by other high-income countries,” Ho said.

The researchers said the epidemic is being driven by factors that include fee-for-service reimbursement systems and linking doctors’ pay to patient satisfaction.

Other factors include commercial hyping of the opioid painkiller OxyContin (oxycodone), American attitudes about pain and medicine, and the lack of substance abuse treatment. In the United States, only about 10% of addicts receive treatment, the researchers noted.

While America leads in overdose deaths, increases in overdose deaths are starting to crop up in Australia, Canada and the United Kingdom, Ho noted.

A common challenge

Australia has seen a 14-fold increase in oxycodone use between 1997 and 2008, and Ontario, Canada, saw an 850% increase in oxycodone use between 1991 and 2007. These increases have resulted in many more overdose deaths in both nations, the study showed.

Although the American opioid epidemic started with prescription drugs, it is now becoming an epidemic of heroin and fentanyl, which is also affecting other countries.

“The use of prescription opioids and synthetic drugs like fentanyl are becoming increasingly common in many high-income countries and constitute a common challenge to be confronted by these countries,” Ho said.

For the study, Ho and colleagues used data from the Human Mortality Database and the World Health Organization Mortality Database for 18 countries, along with data from vital statistics agencies in Canada and the United States.

The report was published in the journal Population and Development Review.

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Teen boys who are unfit and/or obese have higher odds for chronic disease and disability as adults, according to a large Swedish study.

Researchers followed more than 1 million boys for an average of 28 years, starting when they were 16 to 19 years of age.

Those who were inactive, obese or both as teens were more likely to receive medical disability pensions as adults. The pensions are granted in some countries to working-aged adults who are unable to work due to chronic illness or injury.

“Cardiorespiratory fitness and obesity already in adolescence is strongly related to later health,” said lead researcher Pontus Henriksson, a registered dietitian at the Karolinska Institute in Huddinge, Sweden.

His team cautioned that this study does not prove that being unfit or obese as a teenager causes disabilities in adulthood, only that the two appear to be related.

Less fit than before

This association, however, is important because many teens are less fit and weigh more than previous generations, Henriksson said.

The study also provides more evidence for the relevance of fitness and obesity in adolescence as markers of future health.

Morbidly obese men were at greatest risk, the study found.

Henriksson and his colleagues also found that compared with being unfit, being moderately or highly fit was related to a reduced risk for disability, whether one was obese or not.

Common disabilities associated with poor fitness included muscle problems and debilitating injuries, nervous system diseases, circulatory problems and tumors, as well as mental problems, researchers found.

“We need to increase our efforts to promote physical activity and prevent obesity starting in childhood,” Henriksson said.

Never too early to exercise

Dr David Katz, director of the Yale-Griffin Prevention Research Center in New Haven, Connecticut, reviewed the findings.

“In preventive medicine, we routinely point out that it’s never too late to do something to protect your health,” he said. “This paper reminds us that it’s never too early, either.”

And while this study only showed an association between early inactivity and later disability, abundant evidence suggests this pattern is causal, Katz said.

Being active and managing weight can be a healthy activity that parents and kids can share, he pointed out.

“Parents and children not yet committed to pursuing health together have every reason to make the switch,” Katz said.

“We all want the people we love to be healthy and vital. Parents can help their kids get there and kids can help their parents. Health, like love, is for sharing,” he noted.

The report was published on February 11 in the Annals of Internal Medicine.

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In the race to conception, the female body is set up to separate weak sperm from strong, researchers report.

A woman’s reproductive system presents a veritable obstacle course that stress-tests sperm, making sure that only the strongest swimmers have a chance of reaching a woman’s egg, according to a new study.

Narrow gate-like passages within the female reproductive tract force competing sperm to barge their way through, ensuring that weak and less viable sperm are left behind, the researchers explained.

“It’s survival of the fastest swimmers,” said Dr Harry Fisch, a clinical professor of urology and reproductive medicine at Weill Cornell Medical College in New York City. Fisch was not involved in the study.

“The ones that are swimming properly and… can make it through the openings of the female reproductive system are the ones with the best chance of fertilization,” he explained.

This new knowledge will help couples struggling to conceive a baby, either by giving natural conception a boost or by improving the process of in vitro fertilisation, reproductive medicine experts said.

Sperm count has been an ongoing focus of reproductive medicine, but doctors haven’t been sure which of three main features is most important, Fisch said.

Doctors evaluating sperm look at concentration (the number of sperm), morphology (the shape of the sperm), and motility (the percentage of sperm that are swimming), Fisch said.

Emphasis on sperm motility

To aid conception, doctors first focused on sperm concentration, counting the number of sperm in a man’s ejaculate, Fisch said.

“After that, the shape of the sperm was thought to be critical,” Fisch said. “The shape of the sperm had to be a certain oval, a certain length and width, no defect. We thought that was even more critical than sperm concentration.”

The new study indicates that doctors have not placed enough emphasis on sperm motility, Fisch said.

“We see so many sperm in our practices that don’t swim too much. They swim a little bit and we think it’s probably fine,” Fisch said. “This gives you information that, for natural conception, motility is more important than we thought.”

For this study, researchers at Cornell University created a device that replicated the fluid mechanical properties of microscopically narrow junctions inside the female reproductive tract. They call them “strictures.”

The investigators found that sperm from both humans and bulls tended to collect at strictures. At that point, fluid mechanics sorts the sperm out, with slower swimming sperm swept back while faster swimmers continue to press forward.

Both human and bull sperm moved in a butterfly-shaped path along the stricture entrance, and only sperm able to achieve a certain speed appear able to maintain a path that would help them continue along the reproductive tract.

Could improve IVF

“In nature, when you start off in a normal setting of 60 to 100 million sperm trying to achieve fertilisation with one egg, millions of years of evolution have fine-tuned a system that seems to give us the most optimal outcomes,” said Dr Natan Bar-Chama, director of the Center of Male Reproductive Health at Reproductive Medicine Associates of New York. He’s also an associate professor with the Icahn School of Medicine at Mount Sinai in New York City.

Fisch said that the information gained from this lab experiment could improve lab-assisted reproduction by keeping it as natural as possible.

To give a male partner’s sperm a better chance, doctors might inject it farther up into the female reproductive tract, Fisch said. That would provide a short-cut past the strictures, while still providing for some competition between sperm in their quest for the egg.

Doctors also could “wash” the sperm as a means of improving their swimming strength, Fisch noted.

“You take the ejaculate and you remove the fluid around it and put it in different fluid, so the sperm can move better,” Fisch said. “That’s done every day, but this could lead us to more research into better ways of enhancing sperm movement.”

These findings also could improve in vitro fertilisation, Bar-Chama added.

Currently, doctors pick any sperm and inject it into an egg, he said. By subjecting the sperm to a rigorous test of the sort used in this experiment, a fertility expert would be able to choose from the strongest sperm.

“When we have these powerful technologies that bypass natural reproduction, we still would like to optimize filtration and selection, and potentially this type of research advances that,” Bar-Chama said.

The findings were published on February 13 in Science Advances.

This video below, supplied by the research team, shows sperms’ trajectories as tracked in the study.

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