Managing Chronic Pain in the Primary Care Setting - Brief Article

American Family Physician,  July 1, 2002  by Dawn A. Marcus

• E-mail
• Print
• Link

The National Center for Health Statistics estimates that 32.8 percent of the U.S. general population has persistent or chronic pain symptoms.(1) It is further estimated that 94 million U.S. residents have some form of episodic or persistent pain--whether it be pain associated with cancer, migraine or tension headaches, chest pain, pain from diabetes with neuropathy, arthritis, fibromyalgia, neuralgias, neck and back disorders, facial pain disorders, functional or organic bowel disorders, or pelvic disorders.(2) Unfortunately, treatment for chronic pain rarely results in complete relief and full functional recovery. Of patients diagnosed with chronic pain and treated by a family physician, 64 percent report persistent pain two years after treatment initiation.(3) Not surprisingly, only 15 percent of primary care physicians "enjoy" treating patients with chronic pain.(4)

Although guidelines issued by the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) have increased the role for primary care physicians in managing chronic nonmalignant pain, no particular treatment program is endorsed by guideline-issuing organizations. This absence opens the door for individual primary care physicians and practices to establish guidelines with which they are most comfortable. Primary care physicians should develop comfort in managing routine chronic pain and identify circumstances when subspecialty referral is indicated based on pain severity, associated comorbidity, disability, or increased risk of medication abuse and misuse.

Identifying Routine Chronic Pain

Pain persisting for three months is unlikely to resolve spontaneously and should be treated.(5) Patients who have a favorable prognosis for complete pain relief after an injury tend to have a relatively short duration of pain, low psychologic distress, good work history, and a high level of premorbid physical activity.(6) Poor response to therapy and development of recalcitrant pain characteristics can be predicted when the patient has a history of prior pain, family history of chronic pain, psychologic symptoms, lack of social support, poor employment history, pending litigation, or dissatisfaction with current medical treatment.(7,8)

Managing Routine Chronic Pain

Physicians should identify medical conditions that require specific therapy (e.g., joint or disc abnormalities, neuropathic pain), identify any comorbid psychiatric illnesses, assess for musculoskeletal abnormalities and physical disability, and inform patients of what their expectations should be from pain therapy (improved function, sleep, and mood; and pain reduced to moderate levels). Management plans should include treating comorbid illnesses and disability, with consideration for subspecialty referrals for appropriate care and therapy (i.e., psychologic or psychiatric care, physical or occupational therapy). Further pharmacotherapy recommendations should be contingent on the patient's active compliance with the treatment program. Analgesics such as tramadol (Ultram) can be used to treat moderate to moderately severe pain; opioid analgesics can be used to treat severe and disabling pain.

The use of opioids should be considered only in patients who have a clear medical diagnosis, disabling pain, no recent or active history of medication or alcohol abuse, compliance with treatment recommendations, and pain that has not responded to analgesic or neuropathic medication therapy. Opioids should not be prescribed for new patients who are not acutely ill until the points above have been clarified.

Immediate-release opioids can be used infrequently for pain flares (e.g., 5 to 10 mg of hydrocodone [Vicodin] or oxycodone [Percocet] every six to eight hours) up to three days a week. Sustained-release opioids can be used for constant and disabling pain. Dosing of sustained-release opioids can be accomplished by converting required doses of short-acting agents or by using low doses in opioid-naive patients. Sustained-release opioids may be increased from initial low dosages to maximum low-moderate maintenance dosages:

* 10 to 20 mg of sustained-release oxycodone twice daily

* 15 to 30 mg of sustained-release morphine twice daily

* 5 to 10 mg of methadone twice daily

* 25 mcg of fentanyl (Duragesic) every 48 to 72 hours

Physicians should be familiar with equivalent doses of common immediate-release agents and sustained-release opioids. For hydrocodone and oxycodone, the equivalent of four to eight 5-mg tablets daily equals about 10 mg of sustained-release oxycodone twice daily, or 15 mg of sustained-release morphine twice daily. The equivalent of 10 5-mg hydrocodone or oxycodone tablets daily is about 25 mcg of fentanyl every 48 to 72 hours (transdermal) or 5 mg of methadone twice daily.

Most patients obtain pain relief with low to moderate opioid doses, with no significant incremental advantage to higher doses. The goals of opioid therapy are to improve function by 50 percent, reduce pain to moderate levels (at a score of 6 on a scale of zero [no pain] to 10), reduce excessive analgesic use, and reduce emergency department visits. Patients failing to achieve these goals with low to moderate opioid doses should be referred for subspecialty evaluation. Opioid compliance should be ensured by providing prescriptions only when due and by use of routine urine toxicology testing. Interestingly, patients with chronic pain are not more likely to abuse medications than patients without chronic pain.(9)