U.S. Falls to 8th Globally in Per Capita Opioid Sales

By Pat Anson, PNN Editor

Concerns about opioid addiction and overdoses have caused opioid sales to plummet in the United States in recent years. Opioid consumption has fallen so sharply that Canada, Australia and several European countries have overtaken the U.S. and become the highest consumers of opioid analgesics, according to a new study.

But in many poor and middle-income countries, access to opioids remains very limited, causing unnecessary pain and suffering for millions of sick and dying people.

“There are still concerningly low rates of opioid use in large parts of the world, even in numerous middle-income countries,” said lead author Wallis Lau, PhD, a Lecturer at the School of Pharmacy, University College London.

“Opioids have been listed by the World Health Organization as an essential class of medicine for acute pain, cancer-related pain, and palliative care since 1977, so it is troubling that in many parts of the world, people are unable to access this medicine. There is an urgent need to tackle the global gap in opioid access.”

Lau and her colleagues analyzed global pharmaceutical sales in 66 countries from 2015 to 2019. They found that opioid use in some African and South American countries was less than one tenth of 1% of the rates in wealthier countries in North America, Europe and Australia, according to findings published in The Lancet Public Health.

The highest opioid rate was found in Canada, estimated at 988 milligram morphine equivalents (MME) per day for every 1,000 people. That was down from an average of 1,581 MME per day in Canada in 2015.

By comparison, the U.S. rate was 738 MME per 1,000/day, a 45% decline since 2015. Long touted as having the highest per capita opioid consumption in the world, the U.S. now ranks 8th globally in opioid sales.

At the other end of the scale, a group of 12 West African countries reported only 0.01 MME per 1,000/day. A few other countries, including three in South America, reported rates below 1 MME per 1,000/day.

Opioid Sales Per Capita (2019)

SOURCE: THE LANCET

Researchers say the disparities in opioid consumption go beyond factors such as a nation’s wealth, healthcare quality and disease prevalence. For example, wealthy countries such as the United Arab Emirates and Saudi Arabia reported very low rates of opioid use. Kazakhstan also reported low rates of opioid consumption, despite having high cancer prevalence and high cancer death rates.

“Some countries have low opioid analgesic consumption despite a high cancer prevalence, which could suggest inadequate access to opioid analgesics as much-needed pain control,” said Lau.

Overall, global opioid sales increased by 4% annually from 2015 to 2019. Opioid consumption rates increased in most areas that reported low use, including Eastern Europe, Asia, and South America, but not in Africa.

“These findings reinforce the need to recognise palliative care and pain relief as a global public health priority. In countries that already have good access to opioid analgesics, it is important to avoid opioid misuse and overprescribing, without leaving patients undertreated.” said co-senior author Professor Ian Wong of UCL School of Pharmacy and University of Hong Kong.

According to a 2017 international study commissioned by The Lancet, over 25 million people die annually in severe pain because they have little or no access to morphine and other painkillers. Another 35 million people live with chronic pain that is untreated. The Lancet commission said there were several barriers that stood in the way of effectively treating pain, including “opiophobia” – prejudice and misinformation about the medical value of opioids.

“Unbalanced laws and excessive regulation perpetuate a negative feedback loop of poor access that mainly affects poor people,” the commission said.

Current and Former Smokers Have More Pain

By Pat Anson, PNN Editor

There are many good reasons to stop smoking. Within hours, your heart rate and blood pressure will drop, you’ll cough less and feel more energy. Within a few months your lung function will start to improve. And after 20 years, your risk of dying from lung disease or cancer will be about the same as someone who never touched a cigarette.

Unfortunately, one thing that may not improve is your pain. According to a large new study in the UK, former smokers report higher levels of pain than people who never smoked, and their pain levels are similar to people who still continue to smoke.

Researchers at University College London (UCL) analyzed health data from over 220,000 people in the UK who were asked to report how much pain they experienced during the previous 4 weeks and whether it interfered with their work.  

After adjusting for other health factors such as anxiety and depression, current and former daily smokers were more likely to report bodily pain compared to people who never smoked. The difference was small, but considered significant. Surprisingly, the association between smoking and pain was highest in the youngest group of smokers (aged 16 to 34).

The study was observational and did not establish a cause-and-effect relationship between smoking and pain. But researchers say their findings, published in the journal Addictive Behaviors, suggest that regular smoking at any age results in more pain.

“We cannot rule out that there is some other difference between former smokers and never smokers that is causing these surprising results, but we have to consider at least the possibility that a period of daily smoking at any time results in increased pain levels even after people have stopped smoking,” said lead author Olga Perski, PhD, a research associate in UCL’s Department of Behavioural Science & Health.

“This may be due to negative effects of smoking on the body’s hormonal feedback loops or undiagnosed damage to body tissues. This is certainly an issue that needs looking into.” 

Another possibility is differences in personality. People who take up smoking may handle the psychological stress of illness differently than non-smokers or have a lower level of pain tolerance, which makes them feel pain more acutely. A large study in Norway, for example, found that smokers and former smokers were more sensitive to pain than non-smokers, who had a higher pain tolerance.

Regardless of the reason, smoking is linked with many negative health consequences.

“The possibility that smoking may increase lifelong pain is another important reason not to take up smoking in the first place,” said Perski.

Studies have also found that smoking increases your chances of having several types of chronic pain conditions, such as degenerative disc disease.

A 2011 study of over 6,000 Kentucky women found that those who smoked had a greater chance of having fibromyalgia, sciatica, chronic neck pain, chronic back pain and joint pain than non-smokers. Women in the study who smoked daily more than doubled their odds of having chronic pain.

Genetic Defect Holds Secret to Pain Free Life

By Pat Anson, Editor

An experimental study on genetically modified mice may have uncovered a way to make low doses of opioids more effective in treating chronic pain.

Researchers at University College London are studying “transgenic” mice that were modified to carry a genetic mutation from humans who are unable to feel pain. The humans have a defect in their nervous system that prevents them from sending pain signals through a sodium channel known as Nav1.7. People born without working Nav1.7 can still feel touch normally, but not pain.

The researchers found that that mice who lack Nav1.7 produce higher than normal levels of naturally-produced opioids. Transgenic mice have twice the levels of natural opioids as unmodified mice from the same litter.

To block the effects of the natural opioids, the researchers gave the mice naloxone, an opioid blocker used in addiction treatment, and found that they became able to feel pain.

They also gave naloxone to a 39-year-old woman with the same rare mutation and she felt pain for the first time in her life.

"Studying the mice showed us what was going on in the nervous system that led to painlessness and our findings were directly translatable to humans, as confirmed by the painless patient,” said senior author Professor John Wood, University College London.

"The secret ingredient turned out to be good old-fashioned opioid peptides, and we have now filed a patent for combining low dose opioids with Nav1.7 blockers. This should replicate the painlessness experienced by people with rare mutations, and we have already successfully tested this approach in unmodified mice."

Broad-spectrum sodium channel blockers are already used as local analgesics, but they are not suitable for long-term pain management because they cause complete numbness and can have serious side-effects over time.

Opioid painkillers such as morphine are effective at reducing pain, but long-term use can lead to dependence and tolerance. As the body becomes used to opioids, they become less effective and higher doses are needed. Side effects also become more severe.

"Used in combination with Nav1.7 blockers, the dose of opioid needed to prevent pain is very low," explains Wood. "People with non-functioning Nav1.7 produce low levels of opioids throughout their lives without developing tolerance or experiencing unpleasant side-effects. We hope to see our approach tested in human trials by 2017 and we can then start looking into drug combinations to help the millions of chronic pain patients around the world."

Wood’s study is being published in the journal Nature Communications. Wood has filed for an international patent on his discovery.