Treatments for Low Back Pain: Examining the Evidence for Efficacy
In February of 2016, the Agency for Healthcare Research and Policy (AHRQ) issued a Comparative Effectiveness Review entitled “Noninvasive Treatments for Low Back Pain.”1 The review was designed to “examine the evidence on the comparative benefits and harms of noninvasive treatments for low back pain.” It expands upon a previous review2,3 issued by the American Pain Society (APS) and the American College of Physicians (ACP). The current review also includes electronic databases through April 2015, reference lists, and clinical trial registries.
A total of 156 publications were included, with most trials enrolling patients with pain symptoms of at least moderate intensity (eg, >5 on a 0- to 10-point numeric rating scale for pain). Both radicular and nonradicular low back pain were included. Comparators included placebo, no treatment, usual care, sham therapy, an inactive therapy, or another active therapy.
The review focused on adults with low back pain of any duration (categorized as acute [<4 weeks], subacute [4 to 12 weeks], and chronic [≥12 weeks]), including nonradicular low back pain, radicular low back pain (eg, due to herniated disc), and symptomatic spinal stenosis. The researchers evaluated the effects of interventions measured according to outcomes listed in Table 1. Pain intensity was the most commonly reported outcome, followed by back-specific function, which typically was measured by using the Roland-Morris Disability Questionnaire (RDQ) or the Oswestry Disability Index (ODI).
Questions Addressed by the Review
The researchers set out to answer two key questions.
Key question 1: What are the comparative benefits and harms of different pharmacologic therapies for acute or chronic nonradicular low back pain, radicular low back pain, or spinal stenosis? (Table 2)
Key question 2: What are the comparative benefits and harms of different nonpharmacologic noninvasive therapies for acute or chronic nonradicular low back pain, radicular low back pain, or spinal stenosis? (Table 3)
Observed benefits were generally small to moderate (5 to 10 points on a 100-point visual analog scale or equivalent, or standardized mean difference [SMD] of 0.2 to 0.5 and 10 to 20 points, or SMD of 0.5 to 0.8) respectively for pain. Effects on function were typically smaller than effects on pain, or were unclear. Other outcomes (eg, quality of life, mood, employment, analgesic use, or use of resources) were inconsistently reported and no reliable conclusions could be reached. Benefits were usually measured at short-term follow-up.