Chronic Pain Division Overview
Physicians and investigators in the Chronic Pain Division are engaged in collaborative, translational programs aimed at understanding chronic pain disorders. Translational teams with multidisciplinary interests and strengths in basic and clinical science skills work closely to identify areas of urgent need for better research and treatment in these disparate and complicated pain disorders.
Understanding chronic pain
Pain is the number one reason that patients seek medical care and there are currently more people in the United States suffering from chronic pain than those diagnosed with cancer, cardiovascular disease, and diabetes combined. Researchers in the Chronic Pain Division of the IND are investigating the mechanisms that separate and define chronic pain conditions in an attempt to develop more effective therapeutic treatments. From chronic pain arising from disease, such as diabetes or cancer, to pain syndromes with no associated pathology, such as fibromyalgia, migraine and chronic pelvic pain syndromes, our goal is to understand how the affected tissues and brain communicate, or more importantly, are having the wrong conversation.
Julie Christianson, PhD
Andrea Nicol, MD
Expertise within the Chronic Pain Division focuses on the following conditions:
Fibromyalgia and related musculo-skeletal pain syndromes: Chronic conditions characterized by pain and tenderness of muscles, tendons and joints. Patients affected by the syndrome often suffer from chonic fatigue syndrome, and the majority has sleep disorders. It is most commonly diagnosed in women between 40 and 55, frequently in association with the onset of menopause. Ninety percent of patients with fibromyalgia are women, affecting up to 8 million women in the United States. Related female-prevalent musculo-skeletal pain disorders include conditions such as osteoarthritis.
Migraine headaches are characterized by a feeling of throbbing or pulsing, often on one side of the head. This is often accompanied by nausea and hypersensitivity to light, sounds, and smells. Approximately 75 percent of all migraine sufferers are women, and a change in hormonal status during the reproductive cycle is a frequent trigger. Some 30 million people in the United States suffer from migraines.
Pelvic pain is estimated to affect 17 percent of the adult female population, and more than 90 percent of individuals with pelvic pain are women. This painful condition is sometimes associated with endometriosis in women of child-bearing age. However, one type of pelvic pain (vulvar vestibulitis) has been noted to occur following use of oral contraceptives at an early age, while another (dysesthetic vulvodynia) often occurs at the onset of menopause.
Much anecdotal evidence suggests that pain disorders are often preceded by specific events or conditions. For example, fibromyalgia is sometimes preceded by a viral infection and precipitated and exacerbated by fatigue, lack of sleep and possibly nutritional factors. Similarly, migraines are often associated with hormonal changes occurring at the onset of puberty and during the normal reproductive cycle. Pelvic pain has also been tied to use of birth control at an early age and to menopause. With a better understanding of what triggers pain syndromes, we will be armed to develop strategies to prevent and treat these disorders.
- IND: Women's Pain Division (WPD) researchers are already looking at the role of improved sleeping habits on progression of fibromyalgia.
Why some pain disorders occur predominantly in women is unclear. However, a role of female reproductive hormones has been long suspected.
- IND: Research by WPD investigators has shown that estrogen and related hormones do alter sensory responses to uncomfortable stimuli in animal models. Ongoing studies are aimed at determining the extent to which hormones may play a role in female pain disorders.
There is mounting evidence that these pain syndromes are rooted deeply in the biology of the nervous system. Some types of pain are associated with increased amounts of certain proteins that can affect the excitability of pain-sensing pathways. Estrogen can affect the proteins that alter nervous system properties and can affect sensitivity of the nerves themselves. Some tissues that are affected in female pain syndromes have been shown to have greater than normal numbers of nerves.
- IND: WPD researchers have been aggressively investigating physical and chemical changes in the nervous system (neuroplasticity) associated with acute and chronic pain, and with changes in hormone status.
Because there may be no overtly obvious damage or deformity, female pain disorders are typically very difficult to diagnose. Indeed, this may contribute to the under-diagnosing of these very common pain syndromes. A major part of the problem is a lack of good markers for pain disorders.
- IND: By better understanding the nature of female pain conditions, investigators at the WPD will be better positioned to identify markers of certain disease states, such as elevation of certain blood proteins, genetic modifications, and brain imaging patterns. ‘Biomarker' identification will not only facilitate diagnosis but may predict which therapeutic approaches are best suited to a particular pain syndrome.
Our ability to address some symptoms associated with female pain syndromes has advanced rapidly in recent years. In addition to behavioral management techniques that improve quality of life, this includes development and marketing of new drugs such as triptans for migraines and anti-seizure medications for pelvic pain and fibromyalgia. However, treatments to date are essentially all aimed at the symptoms rather than the causes.
- IND: Researchers and physicians of the WPD take a multidisciplinary approach by applying information they obtain from investigating the mechanisms of women's pain towards cure. These approaches include developing new strategies toward preventing triggers from initiating chronic pain, to the quest for identifying new drugs and behavioral interventions that can treat pain disorders by addressing the basic biological mechanisms.