It is estimated that 50 million people in theUnited States suffer from chronic pain—the number one cause of disability in thiscountry.1 Pain is the primary reason for seekinghealthcare, resulting in more than $100billion in direct medical costs each year.2
Pain is complex and has been defined alongseveral dimensions that have helped to guideboth research and clinical practice. One of themost important divisions for the diagnosis andtreatment of chronic pain is nociceptive versusneuropathic pain (NP). Nociceptive painresults from events that produce tissue damageor that may be damaging to tissues.3,4 Incontrast, NP arises secondary to nervous systemdamage or dysfunction and is often maintainedlong after demonstrable damage totissues has healed.3,5,6
NP has a profound negative impact onquality of life7 and can be difficult to treat.Although the overall prevalence of NP is notknown, painful diabetic peripheral neuropathy(DPN) is a common complication of longstandingdiabetes, a disease that affectsnearly 21 million people in the UnitedStates.8,9 The first article in this supplementreviews the etiology and diagnosis of NP, witha focus on 2 of the conditions most oftenassociated with this condition, DPN andpostherpetic neuralgia (PHN). This articlepoints out that patients with DPN or PHNmay present with a variety of NP symptoms,and it is important to distinguish these conditionsfrom other pain syndromes so appropriatetherapy can be initiated.
The second article reviews the societaland patient burdens associated with NP. Thepresented results document the profoundnegative impact of NP on quality of life andthe particularly debilitating effects of thetriad of chronic pain, sleep disturbances,and depression/anxiety that is present inmany patients with NP. It is critical thatpatients with NP be evaluated for comorbiditiesand that integrated therapy addressboth pain and other patient conditions torestore functionality and quality of life.
The third article reviews current therapyfor NP. Although a wide range of agents havebeen used to treat people with this condition,only 4 (ie, lidocaine patches 5%, duloxetine,gabapentin, and pregabalin) areapproved for the treatment of painful DPNand PHN. The clinical efficacy and safety ofthese agents are reviewed in detail. Theinformation in this supplement will providepractitioners with increased understandingof how to assess, treat, and manage patientswith conditions that give rise to NP, as wellas how to deal with their comorbidities.
Corresponding author: Bill McCarberg, MD, Chronic Pain ManagementProgram, Kaiser Permanente, 732 North Broadway, Escondido, CA 92025.E-mail: email@example.com.
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