Long-term follow-up of three randomized controlled trials

Anne F. Mannion, PhD
The Spine Journal: Available online 5 November 2013: In Press

Abstract
Background context
Chronic low back pain (cLBP) represents a major challenge to our health care systems. The relative efficacy of surgery over nonoperative treatment for the treatment of cLBP remains controversial, and little is known of the long-term comparative outcomes.

Purpose
To compare the clinical outcome at long-term follow-up (LTFU) of patients who were randomized with either spinal fusion or multidisciplinary cognitive-behavioral and exercise rehabilitation for cLBP.

Study design/setting
Long-term clinical follow-up of three multicenter randomized controlled trials (RCTs) of surgery (instrumented or noninstrumented fusion, stabilization) versus nonoperative treatment (multidisciplinary cognitive-behavioral and exercise rehabilitation) in Norway and the United Kingdom.

Patient sample
A total of 473 patients with cLBP of at least 1 year’s duration who were all considered candidates for spinal fusion.

Outcome measures
The primary outcome was the Oswestry Disability Index (ODIv2.1a for the United Kingdom and ODIv1 for Norway) score measured at LTFU. Secondary outcomes included visual analog scale (VAS) pain intensity, pain frequency, pain medication use, work status, EuroQol VAS for health-related quality of life, satisfaction with care, and global treatment outcome at LTFU.

Methods
Patients who consented to LTFU (average 11.4 [range 8–15] years after the initial treatment) completed the outcome questionnaires.

Results
Of 473 enrolled patients, 261 (55%) completed LTFU, 140/242 patients randomized to receive surgery and 121/231 randomized to receive multidisciplinary cognitive-behavioral and exercise rehabilitation. The intention-to-treat analysis showed no statistically or clinically significant differences between treatment groups for ODI scores at LTFU (adjusted for baseline ODI, previous surgery, duration of LBP, sex, age, and smoking habit): the mean adjusted treatment effect of fusion was −0.7 points on the 0–100 ODI scale (95% confidence interval [CI], −5.5 to 4.2). An as-treated analysis similarly demonstrated no advantage of surgery (treatment effect, −0.8 points on the ODI (95% CI, −5.9 to 4.3). The results for the secondary outcomes were largely consistent with those of the ODI, showing no relevant group differences.

Conclusions
After an average of 11 years follow-up, there was no difference in patient self-rated outcomes between fusion and multidisciplinary cognitive-behavioral and exercise rehabilitation for cLBP. The results suggest that, given the increased risks of surgery and the lack of deterioration in nonoperative outcomes over time, the use of lumbar fusion in cLBP patients should not be favored in health care systems where multidisciplinary cognitive-behavioral and exercise rehabilitation programmes are available.

Journal Abstract:  http://www.sciencedirect.com/science/article/pii/S1529943013012230