Prognosis of acute and persistent low back pain

General

Clinical Question:
What is the usual course of acute low back pain and of persistent low back pain?

Bottom Line:
Most patients with acute low back pain have significant improvement at 6 weeks, although some will still have significant pain at 1 year after presentation. (LOE = 1a-)

Reference:
Menezes Costa L da C, Maher CG, McAuley JH, et al. The prognosis of acute and persistent low-back pain: a meta-analysis. CMAJ 2012;184(11):e613-624.  [PMID:22586331]

Study Design:
Meta-analysis (other)

Funding:
Self-funded or unfunded

Setting:
Various (meta-analysis)

Synopsis:
Prognosis is important; it gives our patients realistic expectations, which may help avoid frustration, overtesting, and overtreatment. The authors of this systematic review did a careful search for any inception cohort studies; that is, studies that assembled a group of patients with back pain and followed them forward in time. The authors did not include randomized trials or even the untreated arms of randomized trials, arguing that these studies often have fairly narrow inclusion criteria that hurt generalizability. They identified 2 groups of cohort studies, one of patients with acute and subacute low back pain (less than 12 weeks duration) and one of patients with persistent back pain (12 weeks to 12 months). Studies were of reasonable quality, with approximately three fourths having less than 20% lost to follow-up. Of 21 cohort studies reporting pain as an outcome, 15 included patients with acute low back pain and 6 patients with persistent low back pain. The authors adjusted the duration of symptoms based on the mean or median duration of symptoms prior to entry into the study. For patients with acute low back pain, pain on a 100-point scale decreased from 69 at baseline to 28 at 6 weeks, 12 at 26 weeks, and 4 at 1 year. For patients with persistent low back pain, the pain score was 55 at 6 weeks, 29 at 26 weeks, and 17 at 1 year. Disability scores followed a similar pattern for those with persistent low back pain: the score was 51 at baseline, 28 at 6 weeks 19 at 26 weeks, and 15 at 1 year. For acute low back pain, diability scores were 57 at baseline, 28 at 6 weeks, 17 at 26 weeks, and 11 at 1 year.

Prognosis of acute and persistent low back painis the Evidence Central Word of the day!