Posted tagged ‘pain’

Stanford headache specialist demystifies migraine auras

July 12, 2017

I have close friends who get debilitating migraines so I knew a bit about auras, which are sensory disturbances that often precede migraine headaches. But experiencing one myself was still quite frightening.

It snuck up on me: I was happily reading a novel in bed when a spot on the page became blurry, even when I closed one eye. It quickly expanded in size, turning into a flickering, zig-zag pattern. After checking online and guessing that I probably had a migraine aura, I tried to go to sleep — and that’s when it really got weird. Suddenly I saw the geometric pattern in color moving across my field of vision, even when I had my eyes closed.

Luckily, my aura lasted less than 30 minutes, so I was eventually able to go to sleep. I was also very happy to avoid the unbearable headache pain common in migraines. But my experience inspired me to learn more about auras.

According to Stanford neurologist Nada Hindiyeh, MD, about 30 percent of people that suffer from migraines get an aura before their headache pain. However, migraine auras can also occur without a headache. This used to be called an ocular migraine, but it is now classified by the International Headache Society as a “typical aura without headache,” she said.

“Aura is a term used to describe focal neurological disturbances that precede a migraine headache and typically develop over a 5 to 60 minute period and last less than an hour. The most common neurological symptoms include visual changes,” said Hindiyeh, who works at the Stanford Headache Clinic. “During a visual aura, people may describe a blind spot in part of their field of vision, sparkles or stars, colored spots, zig-zag lines, flashes of light or tunnel vision.”

A migraine aura is thought to be initiated by a phenomena in the brain known as cortical spreading depression — a self-propagating wave of electrical silence in which cortical neurons stop firing and go quiet. This starts a chain of reactions in the brain that causes the various symptoms of a migraine attack, Hindiyeh explained.

A long list of factors can trigger migraines, she said, including stress, changes in sleep patterns, hormonal changes in women, skipping meals, and eating certain foods and beverages such as high processed foods and excessive caffeine.

“Migraine symptoms can change throughout a person’s lifetime. Attacks of migraine aura without a headache are more common as migraine sufferers get older,” Hindiyeh said. “However, if you are older than the age of 40 and develop a migraine with aura for the first time, you should be evaluated by a neurologist. If needed, you may then be referred to a headache specialist.”

And it turns out I’m not the only one who finds auras frightening. “Having an aura can be quite a scary experience,” Hindiyeh said. “Talk to your doctor about what steps to take when you do have one, such as pulling over if you’re driving, taking deep breathes, lying in a dark room or taking specific medication. That way you have an action plan in place and are prepared when an aura comes on.”

Hindiyeh said she has focused her research and practice on migraines because she believes it to be an underdiagnosed and undertreated disease. “Migraine affects 36 million people nationwide and is the seventh leading cause of disability worldwide. These statistics are staggering. I felt that this was a field in neurology where I could hopefully provide care for many patients, and raise awareness about this disabling disease.”

This is a reposting of my Scope blog story, courtesy of Stanford School of Medicine.

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Pain catastrophizing linked to opioid use, particularly for women, Stanford study shows

June 15, 2017

Photo by ZeeNBee

Our nation is struggling with an unprecedented opioid epidemic, which is pushing researchers to better understand how people experience pain and how this is impacts pain treatments.

A key factor may be something called pain catastrophizing — heightened negative thoughts and emotions in response to actual or anticipated pain. New research recently published in Anesthesiology shows that pain catastrophizing is a risk factor for prescription opioid misuse, and the role it plays is different for men and women. I connected with Beth Darnall, PhD, a Stanford clinical associate professor of anesthesiology, perioperative and pain medicine, to learn more about her new study, whose first author is Yasamin Sharifzadeh-Moghaddam, a medical student at Virginia Commonwealth University.

What is pain catastrophizing?

“Pain catastrophizing is the rumination and magnification of pain, and feelings of helplessness about it. People who catastrophize have a hard time thinking of anything but their pain. It’s common for people with chronic pain to catastrophize to some degree, but when it gets into the clinical ranges it indicates a need for treatment. Treatment involves learning targeted ways to redirect one’s attention, calm the nervous system in the face of pain and stress and cultivate awareness about what one can do to feel better. I think virtually everyone with chronic pain can benefit from learning skills that empower them to have better control over their pain and distress — even those who are not high catastrophizers.”

What inspired you to research pain?

“First, I was intensely curious about pain and why it varies between individuals; a lot of the “why” ends up involving psychological factors. I was fascinated with the connection between stress and pain and wanted to learn more about how they relate. … I also wanted to help people on a broader scale. I can only see a few individual patients in the clinic, but if I develop a treatment that others can use, the ripple effect potential is tremendous.”

How did you investigate the impact of pain catastrophizing on opioid use?

“Pain catastrophizing is associated with greater use of opioids after surgery and with opioid misuse. Across multiple studies, catastrophizing associates strongly with pain intensity, so we wanted to better understand how it might relate to pain medication.

In our study, we looked at patients receiving a new evaluation at the Stanford Pain Management Center. We examined the relationships between pain intensity, pain catastrophizing and existing opioid prescription. We used the Collaborative Health Outcomes Information Registry, a free open source health outcomes platform, to collect data on almost 1800 patients. We aimed to reveal whether sex differences existed for opioid prescription and our other variables of interest, using modeling to explore the associations. We found that almost 60 percent of patients referred to our center are taking prescription opioids, and people with greater pain were more likely to be taking opioids.

We also found that sex matters in the equation. For women, the relationship between pain catastrophizing and opioids occurred at much lower levels of pain catastrophizing than for men. Our data suggest that catastrophizing may be more impactful for women, and that these associations begin to appear at what we previously called ‘subthreshold’ levels. More research is needed to replicate our findings and to understand why we see these sex differences in catastrophizing and opioid prescription. I’m speculating, but women may be better communicators of pain-related distress — verbally and nonverbally — and this may translate into a prescription at the end of a medical visit.”

How can your results improve future clinical practice?

“If replicated, our findings signal that we should be treating our patients before frank problems arise. If we address psychosocial distress early on, we may prevent worsening of symptoms into clinical problems and the need for various treatments. We also need more research to develop a deeper understanding of the relationships between prescription opioids and psychological factors. … Our findings suggest that we need to further examine the prescribing doctor-patient interaction.”

What’s the next step?

“We are currently examining whether presurgical treatment for catastrophizing can reduce post-operative opioid use. Right now we are studying this in women only, but our planned studies include men and women so we can test sex differences in treatment response.”

This is a reposting of my Scope blog story, courtesy of Stanford School of Medicine.

Opioid receptors in brain affect reaction to another person’s pain

June 7, 2017

Image by P. Simonau

Watching someone else suffering from pain is distressing. What mechanisms cause that distress? And why do some of us experience it more strongly than others?

A new Finnish research study has now demonstrated that seeing others in pain activates the same brain regions involved in firsthand pain, which suggests that a shared neuromolecular pathway processes both types of pain. Specifically, the researchers showed that the endogenous opioid system, but not the dopamine system, contribute to vicarious pain.

The endogenous opioid system is a set of neurons in the brain that naturally produces opioids to help modulate emotions and pain. Similarly, the dopamine system consists of neurons that synthesize and release dopamine, which helps manage motor control, pain, reward and addictive behaviors. So both of these systems are known to play an important role in processing firsthand pain, but their role in vicarious pain was unexplored.

The research team conducted the study by imaging 35 healthy women ranging in age from 19 to 58 years old. First, they performed two positron emission tomography (PET) studies on different days using radiopharmaceuticals that quantified the availability of opioid and dopamine receptors in each woman’s brain to better understand the individual opioid and dopamine systems. Next, they investigated how each woman responded to vicarious pain by performing a functional MRI scan while she watched videos of humans experiencing painful and painless situations.

The researchers found a negative correlation between opioid receptor availability and response to vicarious pain — women with less opioid receptors reacted more strongly to seeing someone else’s distress, as recently reported in Cerebral Cortex. In contrast, they found no correlation with the dopamine receptor availability.

The authors concluded in the paper, “These results suggest that the opioid system contributes to neural processing of vicarious pain, and that interindividual differences in opioidergic system could explain why some individuals react more strongly than others to seeing pain.”

This is a reposting of my Scope blog story, courtesy of Stanford School of Medicine.

New imaging study investigates role of dopamine in migraine attacks

April 7, 2017

Many people suffer from migraines —throbbing, painful headaches that last up to 72 hours and are often accompanied by nausea, vomiting and sensitivity to light and sound.

Although not fully understood, an imbalance in a brain neurotransmitter is thought to contribute to migraines. The neurotransmitter, dopamine, is a chemical in your brain that affects your movements, emotions, motivations and sensory perceptions, including the ability to modulate pain.

Now, researchers at the University of Michigan have shown that dopamine levels in the brain fall during a migraine attack relative to their baseline level between attacks, as reported in a recent news release.

The research team performed two PET scans on different days to study eight migraine sufferers during a spontaneous migraine and in between attacks, comparing their brain activity and dopamine levels with and without a headache. On average, these patients were 27 years old and experienced migraines about six times per month. The scientists also imaged eight healthy adults, comparing migraine sufferers to controls.

They found that dopamine levels in the brain fluctuated, temporarily reducing during migraine attacks. They also found that the study participants were more sensitive to non-painful stimuli, such as warmth applied to the forehead, during a migraine.

“With this study, we better understand how dopamine is related to the suffering during a migraine attack,” said Alex DaSilva, DDS, DMedSc, assistant professor of dentistry and of the Center for Human Growth and Development at the University of Michigan, in the video above. “Lower dopamine levels mean you are more sensitive to pain and stimulation. Second, lower dopamine levels also inhibit your behavior. You want a dark room. You want to avoid social interactions.”

In their paper, the researchers call for additional studies to confirm the results and evaluate how they can be used to develop more effective migraine therapies.

This is a reposting of my Scope blog story, courtesy of Stanford School of Medicine.

Targeting protein may help researchers improve pain medication

January 24, 2017

headache-1910649_1280For many people, living with chronic pain is a way of life. Unfortunately, existing pain medications are not always effective and can be addictive, which has led to an opioid epidemic in the United States.

In their search for better therapies to manage pain, researchers are investigating the underlying mechanisms that signal and control pain in the body. A central component of this pain pathway is a protein called Nav1.7, which is present at the endings of pain-sensing nerves. Nav1.7 is known to help alert your brain when your body encounters potentially harmful stimuli, like when your hand touches a hot pan.

Past research demonstrated that people with non-functioning Nav1.7 don’t feel pain. This discovery led to the development of drugs that block Nav1.7 activity. Unfortunately, these drugs didn’t really work. It turns out that the role of Nav1.7 is more complicated than first thought.

“It seemed so obvious and simple, but it was not so simple,” said Tim Hucho, PhD, a neuroscientist at the University Hospital Cologne in Germany, in a recent Science News story.

Researchers have now found that Nav1.7 plays a second role — triggering the production and release of natural opioid compounds, like endorphins, that suppress the transmission of pain signals to the brain. People with non-functioning Nav1.7 do not feel pain and have increased expression of the genes in charge of making natural opioids.

The news story explains:

“An investigation of rat and mice nerve cells reveals the tug-of-war between Nav1.7’s pain-promoting and pain-relieving powers. Cells with nonfunctioning Nav1.7 have amped up activity in the cellular machinery that kicks off pain relief, Hucho and colleagues report. They suggest that Nav1.7 acts like the axis point in a playground seesaw. When the pain-promoting side is dialed down, the pain-relieving side becomes more dialed up than usual, and cells make more of their in-house opioids.”

This research suggests a new approach to pain management: using opiates in combination with a Nav1.7 blocker to make opiates more effective and reduce their associated side effects. However, a lot more research is needed before this work can be translated into treating people with chronic pain.

This is a reposting of my Scope blog story, courtesy of Stanford School of Medicine.

Researchers discover “brain signature” for fibromyalgia using brain scans

October 27, 2016

portrait-1006703_1280Millions of patients suffering from fibromyalgia often experience widespread musculoskeletal pain, sleep disturbances, fatigue, headaches and mood disorders. Many also struggle to even get diagnosed, since there are currently no laboratory tests for fibromyalgia and the main symptoms overlap with many other conditions. However, new research may help.

Scientists from the University of Colorado, Boulder may have found a pattern of brain activity that identifies the disease. They used functional MRI (fMRI) scans to study the brain activity of 37 fibromyalgia patients and 35 matched healthy controls, while the participants were exposed to a series of painful and non-painful sensations.

As reported recently in the journal PAIN, the research team identified three specific neurological patterns correlated with fibromyalgia patients’ hypersensitivity to pain.

Using the combination of all three patterns, they were able to correctly classify the fibromyalgia patients and the controls with 92 percent sensitivity and 94 percent specificity — meaning that their test accurately identified 92 percent of those with and 94 percent of those without the disease.

Tor Wager, PhD, senior author and director of the school’s Cognitive and Affective Control Laboratory, explained the significance of the work in a recent news release:

“Though many pain specialists have established clinical procedures for diagnosing fibromyalgia, the clinical label does not explain what is happening neurologically and it does not reflect the full individuality of patients’ suffering. The potential for brain measures like the ones we developed here is that they can tell us something about the particular brain abnormalities that drive an individual’s suffering. That can help us both recognize fibromyalgia for what it is – a disorder of the central nervous system – and treat it more effectively.”

More research is needed, but this study sheds a bit of light on this “invisible” disease.

This is a reposting of my Scope blog story, courtesy of Stanford School of Medicine.

The Opioid Crisis: Medicine X panelists explore the complexity of managing chronic pain

September 19, 2016
britt-johnson-on-stage-1024x683

Photograph courtesy of Medicine X

Saturday’s Medicine X session on the opioid crisis focused on how best to manage the chronic pain felt by millions of Americans every day. The session engaged panelists with different perspectives, including a patient in chronic pain and physicians struggling to decide when to prescribe opioids. All the panelists recognized that opioid addiction is a serious and pervasive problem, but they also warned that proper pain management is a complex issue.

Jeanmarie Perrone, MD, professor of emergency medicine at the Hospital of University of Pennsylvania, told the audience, “I need good pain management to work in the emergency room. We need these drugs, we just need to be conscientious about it.”

ePatient Britt Johnson, a Medicine X board member and owner of The Hurt Blogger, understands this all too well. She shared her story of needing opioids to function due to severe pain from spondyloarthropathy and rheumatoid arthritis, which she’s had for most of her life.

Johnson addressed the media’s oversimplification of the issue. “Pain is not politically correct,” she said. “The media tells me that all opioids are all bad. The media makes everyone believe that I, too, am struggling with addiction. And the media lumps me in with statistics on heroin usage and overdose deaths.” She went on to say that she winds up “feeling guilt and shame for constantly experiencing pain. And I’m reminded constantly how heart breaking overdose stories are, which they are. But my story is not connected to those stories.”

Pain expert Frank Lee, MD, agreed that “we’re starting to stereotype chronic opioid patients as heroin addicts and physicians as pill pushers.” Lee described the impact of this on his practice and how it increases his risk if he prescribes a large or moderate dose of opioids to a patient. “If I just follow the CDC guidelines and tell the patient that I can’t prescribe this medication, it makes my life easier,” he said.

Lee shared a story about one of his patients who recently died. In her 70s, Mary had severe rheumatoid arthritis and three back surgeries. When he “inherited” Mary from a different pain doctor, she was on massive doses of opioids — close to 300 mg morphine daily equivalents, several times the recommended dose. “Maybe I was naïve, but I went through all the dangers of opioids. I told her, ‘We need to come down on your dose.’ She was hesitant, but she said ‘if you really need to do this, okay.’ During the next three months, we went down from almost 300 mg to about 70 mg. She ended up in the emergency room twice, because she just couldn’t take it. It hurt too much,” he said. “She cared enough to try what I recommended and I felt like I owed her the chance. We went back to the insane amount of her opioids and she did well.” However, Lee expressed his concern over what the high opioid doses did to her body.

Lee and others discussed the need to distinguish between patients like Johnson and Mary from those who are prone to opioid addiction. Sean Mackey, MD, PhD, chief of the division of pain medicine at Stanford, declared the need for more quality data on pain — through programs like the National Pain Strategy — to help identify the risk factors of the people that are more vulnerable. Cynthia Reilly, director of the prescription drug abuse project at The Pew Charitable Trusts, professed that prescription drug monitoring programs are part of the solution.

The panel agreed that another solution is to make integrated medicine options more affordable. “At the pharmacy I get a bottle of 60 Percocet for ten dollars, yet I have to pay out of pocket for massage, acupuncture, heat therapy, ice packs, cognitive behavioral therapy, pain psychologists and anything else,” said Johnson. “Opioids have the cheapest barrier to access, yet raising the price of opioids is not the answer; putting complimentarily pain therapies on an even playing field is.”

Although mostly harmonious, the panel discussion became heated near the end when a member of the audience interrupted, asking to hear more from Johnson. Feeling that she was being left out of the conversation, she said, “I’m sitting here and the discussion about the pain crisis is happening around me, when I’m right here and it could be happening with me. We could be having a real discussion here.” The panel concluded that we need to do a better job bringing everyone together with different perspectives.

This is a reposting of my Scope blog story, courtesy of Stanford School of Medicine.


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