Chronic Opioid Treatments
The administration of opioids for chronic nonmalignant pain is a controversial issue, yet in general, there is currently no nationally accepted consensus regarding the treatment of chronic pain. There appears to be a select subpopulation of patients with chronic pain that can achieve sustained partial analgesia from opioid therapy without the occurrence of intolerable side effects or the development of aberrant drug-related behaviors.1 Randomized placebo controlled trials with a treatment duration of 1 week or more have shown that opioids are effective in providing analgesia in patients with chronic nonmalignant pain.2,3,4 Randomized trials, however, despite demonstrating analgesia, have not shown changes in functional outcomes and activity level.3,5
Impediments to the use of opioids include concerns about addiction, tolerance, diversion, fear of regulatory action, and side effects such as respiratory depression.6 Studies regarding neuropsychological functioning of patients taking chronic opioids are contradictory and suggest that opioids may impair performance by altering visuomotor coordination. However, the observed effects are not major and appear to be less significant than those observed with other classes of pharmacological agents which are increasingly being used to manage pain.7 Although temporary decline in cognitive function may occur when opioid dose is acutely increased, only a few non-significant cognitive effects are apparent in patients taking chronic and stable doses.8
The rationale for the use of opioids in non-malignant pain is not simply to treat pain, but to improve function. This study was conducted to investigate employment status and whether or not employment status is related to opioid dose in individuals treated chronically with opiates for non-malignant pain. We hypothesized that there would not be a strong relationship between opioid use and employment status.
A retrospective chart review was performed on all patients currently enrolled in our outpatient chronic pain management program. Exclusion criteria were 1) patients over 65 years of age, 2) homemakers, 3) patients with malignant disease, and 4) patients not currently taking opioid medication. These criteria exclude patients who are not expected to be working regardless of their chronic pain.
At each office visit, patients are asked to complete a questionnaire asking employment status, medication dosage, and whether pain is adequately controlled.
Our chronic pain management program is multi-disciplinary and involves a physiatrist, nurse, psychologists and physical and occupational therapists experienced in chronic pain. In our program, patients are prescribed opioid analgesics only after all other reasonable therapies have failed. These include injections, physical and occupational therapy, acupuncture, and various medications. At the onset of the program, patients must sign a contract stating that they will 1) use only one physician for opioid pain treatment, 2) use only one pharmacy for opioid medications, and 3) agree to random urine testing to evaluate compliance and screen for illicit drug use. Violators of this contract are subject to dismissal from the program.
Pain type was divided into four categories 1) musculoskeletal, 2) neuropathic, which included radiculopathy, 3) visceral, which included interstitial cystitis, chronic pancreatitis, and chronic prostitis, and 4) complex regional pain syndrome type I. Comparison of opioid doses was performed by converting various medications to oral morphine equivalents (Table 1). PRN medications were calculated at one half the maximal daily prescribed dose.
|Fentanyl (transdermal)||25 ug/hr 10|
Of the 81 patients’ charts reviewed, 57 patients met our criteria. Thirteen patients were excluded because they were greater than 65 years of age and 11 were excluded because they reported to be housewives / homemakers. The mean age was 45 years (SD=9.6 years) with a range of 26 to 63 years. 29 patients were men and 28 patients were women. Of the patients meeting the above criteria, 59% were noted as being employed. Thirty-one patients were classified with musculoskeletal pain, 11 with neuropathic pain, 9 with complex regional pain syndrome, and 6 with visceral pain.
Opioid medications prescribed included oral codeine, transdermal fentanyl, oral hydrocodone, oral hydromorphone, oral meperidine, oral methadone, oral morphine, oral oxycodone, oral propoxyphene, and several fixed dose oral opioid combinations with aspirin or acetaminophen.
The mean daily dose among employed patients was 563 (SD=858) oral morphine equivalents and among unemployed patients was 452 (SD=682) morphine equivalents. A t-test revealed no significant difference between the employed and unemployed groups with regard to opioid use (t=0.52, p=0.61).
The mean opioid dosage in daily oral morphine equivalents for the four pain categories was as follows: musculoskeletal 306 (SD=288), neuropathic 444 (SD=924), complex regional pain syndrome 853 (SD=1067), and visceral 1247 (SD=1335). A one-way analysis of variance was statistically significant (F=3.44, p=0.02) between the musculoskeletal and visceral categories.
The most common diagnosis in our sample was low back pain (n=18). This sample was analyzed independently. The mean opioid dose was 331 (SD=241) oral morphine equivalents. Of these patients, 72% were employed. A t-test demonstrated no significant difference in opioid dose between the employed and unemployed groups (t=0.20, p=0.85).