BACKGROUND: Some leading German @entity158 medicine experts postulate that there is a type of @entity1118 ( @entity1118 ) with an opioid requirement. We tested whether opioids are superior to nonopioid analgesics in the management of @entity1118 in studies of at least 4  week's duration. METHODS: We screened MEDLINE, Scopus and the Cochrane Central Register of Controlled Trials (CENTRAL) up until October 2013, as well as the reference sections of original studies and systematic reviews of randomised controlled trials (RCTs) of opioids in @entity1118 . We included double-blind RTCs comparing opioids to nonopioid analgesics of at least 4  week's duration. Relative risks differences (RD) of categorical data and standardized mean differences (SMD) of continuous variables were calculated using a random effects model. RESULTS: We included 10  RCTs with 3046  @entity1 . Median study duration was 6  weeks (range  4-12  weeks). Five studies compared tramadol with nonsteroidal anti-inflammatory drugs (NSAIDs) in @entity158 and one trial compared @entity1340 to @entity29588 in @entity1643 . @entity1286 was compared to antidepressants (two studies), an anticonvulsant (one study) and an antiarrhythmic (one study) in different @entity9 syndromes. There was no significant difference between opioids and nonopioid analgesics in @entity158 reduction (SMD  0.03 [95   %  confidence interval, CI  -   0.18, 0.24]; p   =   0.76). Nonopioid analgesics were superior to opioids in improving physical function (SMD  0.17 [95   %  CI  0.02,  0.32]; p   =   0.03). @entity1 dropped out due to adverse events more frequently with opioids than with nonopioid analgesics (RD  0.09 [95   %  CI  0.06,  0.13]; p   <   0.0001). There was no significant difference between opioids and nonopioid analgesics in terms of serious adverse events or dropout rates due to lack of efficacy. CONCLUSION: Nonopioid analgesics are superior to opioids in terms of improvement of physical function and tolerability in short-term (4-12  weeks) therapy of @entity1643 . Our results do not support the concept of an"opioid-requiring" @entity1118 . The English full-text version of this article is freely available at SpringerLink (under "Supplemental").

[Opioids in chronic XXXX -are opioids superior to nonopioid analgesics? : A systematic review and meta-analysis of efficacy, tolerability and safety in randomized head-to-head comparisons of opioids versus nonopioid analgesics of at least four week's duration.]

@entity1 :: ('9606', 'Species') :: ['participants', 'Patients'] @entity1643 :: ('MESH:D017116', 'Disease') :: ['neuropathic, low back and osteoarthritis pain', 'low back pain'] @entity1340 :: ('MESH:D014147', 'Chemical') :: ['tramadol'] @entity29588 :: ('MESH:C034161', 'Chemical') :: ['flupirtine'] @entity158 :: ('MESH:D010146', 'Disease') :: ['osteoarthritis pain', 'pain'] @entity1286 :: ('MESH:D009020', 'Chemical') :: ['Morphine'] @entity1118 :: ('MESH:D059350', 'Disease') :: ['chronic non-cancer pain', 'CNCP'] @entity9 :: ('MESH:D009437', 'Disease') :: ['neuropathic pain']
@entity158 :: (MESH:D010146,Disease) :: ['noncancer pain']
