Patients with chronic pain can be treated successfully if the physician directs the therapy according to the mechanisms that trigger the pain. Recognizing these is a challenge. However, correct diagnoses are possible with simple screening instruments even in the family practice.
Today, one in six patients visits a doctor’s office because of pain. Back pain is particularly common: According to estimates, 80% of Swiss people suffer from back pain at some point in their lives. These can also radiate to the legs and feet.
The causes and triggers are manifold. “In many patients with low back and leg pain, nociceptive and/or neuropathic mechanisms are involved,” explained Prof. Heiko Sprott, MD, of the Pain Clinic in Basel, Switzerland, during a media roundtable discussion hosted by Pfizer.
Nociceptive back pain is due to musculoskeletal injury and is caused by mechanical, chemical, or thermal irritation of peripheral nerves. Neuropathic back pain, on the other hand, results from nerve root compression leading to local inflammation and is often a consequence of a lesion or disease of the somatosensory nervous system. It is estimated that neuropathic mechanisms play a role in 37% of back pain cases.
For neuropathic pain, NSAIDs do not work
“For a good therapy of pain patients, it is important to recognize the mechanisms that trigger pain,” Prof. Sprott emphasized. This is because nonsteroidal anti-inflammatory drugs (NSAIDs) are usually only good at relieving nociceptive pain, but not neuropathic pain. However, these can be treated today with antidepressants or epileptics in low doses.
In Switzerland, some of these agents, such as pregabalin (Lyrica®), are already approved for the treatment of neuropathic pain. They can be administered together with NSAIDs. According to Prof. Sprott, such a combination therapy is indicated in particular for the 40-50% of patients whose back pain has both nociceptive and neuropathic components.
Family physicians can adequately treat many pain patients
Identifying the mechanisms that trigger pain is not always easy in practice. Some symptoms may provide clues. For example, electrifying, burning pain and/or the sensation of tingling or prickling often masks a neuropathic pain component. A sign of a neuropathic cause of pain can also be provided by NSAIDs: when they have no or insufficient effect on pain radiating to the legs and feet.
“Screening tools are helpful for quick and easy identification of neuropathic pain mechanisms in family practice,” said Prof. Eli Alon, MD, of the Pain Management Practice in Zurich. A good instrument is the seven-question pain-detect® questionnaire. It was developed by the German Neuropathic Pain Research Network with Pfizer and is available on the Internet (www.pain-detect.de).
Every patient needs an individual therapy
“If primary care physicians identify the mechanisms that cause pain and adequately treat their pain patients, about half of all patients with back pain can be well managed in general practice,” Prof. Sprott said. However, if the healing process is delayed or the causes of the pain cannot be clearly determined, the family doctor should consult a specialist.
“Moreover, the long-term treatment success of chronic pain patients always requires an individualized and holistic therapy,” Prof. Alon emphasized. This is composed of medications and/or physio-, psycho-, radiofrequency therapies as well as complementary medical methods. “Out of place is the bed rest that some primary care physicians still prescribe to patients with acute back pain,” Prof. Sprott said. According to studies, pronounced sparing could not infrequently also initiate the trajectory of a chronic back pain patient.
“Adequate and holistic treatment of pain patients also makes sense for economic reasons,” the two pain specialists further emphasized. In Switzerland alone, pain patients cost 4 billion Swiss francs, about half of which is attributable to back pain patients. In addition, there are large production losses in the economy because pain patients are no longer as efficient as healthy people. According to estimates, they amount to 61.4% or 2.6-4.9 billion francs annually.
Claudia Benetti
Source: Pfizer Media Round Table, October 11, 2012, Zurich
