TY  - JOUR
A1  - Petzke, Frank
A1  - Klose, Petra
A1  - Welsch, Patrick
A1  - Sommer, Claudia
A1  - Häuser, Winfried
T1  - Opioids for chronic low back pain: An updated systematic review and meta‐analysis of efficacy, tolerability and safety in randomized placebo‐controlled studies of at least 4 weeks of double‐blind duration
JF  - European Journal of Pain
N2  - Background and Objective
This updated systematic review evaluated the efficacy, tolerability and safety of opioids compared to placebo in non‐malignant chronic low back pain.

Databases and Data Treatment
Clinicaltrials.gov, CENTRAL, MEDLINE and PsycINFO were searched from October 2013 to May 2019. Randomized controlled trials comparing opioids with placebo and at least 4 weeks of double‐blinded duration were analysed. Primary outcomes were pain relief of 50% or greater, disability, tolerability and safety. Effects were summarized by a random effects model using risk differences or standardized mean differences. We added nine new studies with 2,980 participants for a total of 21 studies with 7,650 participants. Study duration ranged between 4 and 15 weeks. Studies with a parallel and cross‐over design: Based on very low to low‐quality evidence, opioids provided no clinically relevant pain relief of 50% or greater, but a clinically relevant reduction of disability compared to placebo. Enriched enrolment randomized withdrawal (EERW) design: Based on very low to low‐quality evidence, opioids provided a clinically relevant pain relief of 50% or greater, but not a clinically relevant reduction of disability compared to placebo. There was no clinically relevant harm with regard to serious adverse events by opioids compared to placebo in studies with parallel/cross‐over and EERW design. There was a relevant harm with regard to drop out rates due to adverse events in studies with parallel/cross‐over, but not in studies with EERW design.

Conclusions
Opioids may provide a safe and clinically relevant pain relief for 4–15 weeks in highly selected patients.

Significance
Within the context of randomized controlled trials of 4–15 weeks, opioids provided a clinically relevant pain relief of 30% or greater and a clinically relevant reduction of disability compared to placebo in non‐malignant chronic low back pain. Number needed to treat for an additional drop out due to side effects was 11 (95% confidence interval: 6–33). Assessment of abuse and addiction was incomplete. The frequency of serious adverse events including deaths did not differ from placebo.
KW  - opioids
KW  - back pain
KW  - systematic review
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-218498
VL  - 24
IS  - 3
SP  - 497
EP  - 517
ER  -