Psychiatric disorders and risk of transition to chronicity in men with first onset low back pain.

OBJECTIVE: To assess whether pre-existing psychiatric diagnoses increase the likelihood of transitioning from sub-acute to chronic back pain. DESIGN: Prospective cohort study. METHODS: Men (N = 140) experiencing a first onset of low back pain (LBP) were examined for lifetime psychiatric disorders approximately 8 weeks post pain-onset using the Diagnostic Interview Schedule (DIS-III-R), then re-evaluated at 6 months after pain onset to determine who did or did not progress to pain chronicity. OUTCOME MEASURE: Transition to chronic pain and disability was based on 6-month self-report measures of pain intensity and perceived disability. RESULTS: Men with a pre-pain lifetime diagnosis of major depressive disorder had 5 times greater risk of transitioning to chronic LBP (odds ratio [OR] = 4.99; 95% confidence interval [CI] 1.49-16.76). Increased risk was also associated with a pre-pain lifetime diagnosis of generalized anxiety (OR = 2.45; 95% CI 1.06-5.68), post-traumatic stress (OR = 3.23; 95% CI 1.11-9.44), and with current nicotine dependence (OR = 2.49; 95% CI 1.15-5.40). There were no statistically significant effects for abuse or dependence of alcohol or other psychoactive substances. DISCUSSION: Lifetime history of major depression or a major anxiety disorder may represent potential psychosocial "yellow flags" for the transition to chronicity in men with first-onset LBP. Screening for lifetime depressive or anxiety disorders may identify individuals at higher risk, who may benefit from referral for more intensive rehabilitation.

Preventing progression to chronicity in first onset, subacute low back pain: an exploratory study.

OBJECTIVES: To evaluate the effects of a behavioral medicine intervention, relative to an attention control, in preventing chronic pain and disability in patients with first-onset, subacute low back pain (LBP) with limitations in work-role function. DESIGN: A 2-group, experimental design with randomization to behavioral medicine or attention control groups. SETTING: Orthopedic clinic at a Naval Medical Center. PARTICIPANTS: Sixty-seven participants with first-onset LBP of 6 to 10 weeks of duration and impairment in work function, of whom 50 completed all 4 therapy sessions and follow-up 6 months after pain onset. INTERVENTION: Four 1-hour individual treatment sessions of either behavioral medicine, focused on back function and pain education, self-management training, graded activity increases, fear reduction, and pain belief change; or attention control condition, focused on empathy, support, and reassurance. MAIN OUTCOME MEASURES: The primary outcome was proportion of participants classified as recovered, according to pre-established clinical cutoffs on standardized measures, signifying absence of chronic pain and disability at 6 months after pain onset. Secondary analyses were conducted on pain, disability, health status, and functional work category. Intervention credibility and pain belief manipulation checks were also evaluated. RESULTS: Chi square analyses comparing proportions recovered at 6 months after pain onset for behavioral medicine and attention control participants found relative rates of 52% versus 31% in the modified intent-to-treat sample (P=.09) and 54% versus 23% for those completing all 4 sessions and 6-month follow-up (P=.02). At 12 months, 79% of recovered and 68% of chronic pain participants still met criteria for their respective groups (P<.0001). Recovered participants also had higher rates of functional work status recovery at 12 months (recovered: 96% full duty and 4% light duty; chronic pain: 61% full duty, 18% light duty, and 21% medical discharge, respectively; P=.03). CONCLUSIONS: Early intervention using a behavioral medicine rehabilitation approach may enhance recovery and reduce chronic pain and disability in patients with first-onset, subacute LBP. Effects are stronger for participants attending all 4 sessions and the follow-up assessment.

High-quality controlled trials on preventing episodes of back problems: systematic literature review in working-age adults.

BACKGROUND CONTEXT: Back problems (BPs), with their cost and disability, are a substantial burden for individuals, employers, and society. PURPOSE: This systematic review of controlled trials evaluates the effectiveness of interventions to prevent BP episodes in working age adults. DATA SOURCES: We searched MEDLINE/EMBASE through May 2007, and COCHRANE/Trials Registry through August 22, 2008 using search terms of back pain, back injuries or sciatica, linked to prevention, control, workplace interventions, or ergonomics and searched article bibliographies. STUDY SELECTION: For systematic review inclusion, articles had to describe prospective controlled trials of interventions to prevent BPs in working-age adults, with intervention assignment either to individual participants or preexisting groups. Of 185 articles identified as potentially relevant, 20 trials (11%) met inclusion criteria. DATA EXTRACTION: Researchers extracted relevant information from controlled trials and graded methodological quality. Because of heterogeneity of trials, meta-analysis was not performed. RESULTS: Only exercise was found effective for preventing self-reported BPs in seven of eight trials (effect size 0.39 to >0.69). Other interventions were not found to reduce either incidence or severity of BP episodes compared with controls. Negative trials included five trials of education, four of lumbar supports, two of shoe inserts, and four of reduced lifting programs. CONCLUSIONS: Twenty high-quality controlled trials found strong, consistent evidence to guide prevention of BP episodes in working-age adults. Trials found exercise interventions effective and other interventions not effective, including stress management, shoe inserts, back supports, ergonomic/back education, and reduced lifting programs. The varied successful exercise approaches suggest possible benefits beyond their intended physiologic goals. LEVEL OF EVIDENCE: Systematic review Level I evidence.

Shared and independent associations of psychosocial factors on work status among men with subacute low back pain.

OBJECTIVES: Psychosocial variables are acknowledged predictors of back disability, but multivariate studies are needed to understand their independent and overlapping effects. The objective of this prospective cohort study was to evaluate independent and shared associations of psychosocial variables on work status after first onset of low back pain (LBP) in working men. METHODS: One hundred forty male military personnel reporting subacute, first onset LBP (2 mo average duration) completed an interview-based and survey-based psychosocial assessment within the domains of job satisfaction, stress and coping, pain perceptions and beliefs, perceived functional disability, and mood disturbance. Work status was assessed at baseline, 6 and 12-month postpain onset. RESULTS: In logistic regression analyses at baseline, work status was associated with pain interference and perceptions of physical impairment. Beyond 2 months, the extent to which pain was believed to interfere with function was the only significant predictor of subsequent changes in work status. Job dissatisfaction was associated with more impaired work status, but not after controlling for income. Depressive and anxious mood symptoms were prevalent but failed to explain additional variance in work status. DISCUSSION: After first onset of men with subacute LBP, self-reported pain intensity and functional limitation account for most of the variance in work status explained by psychosocial factors; however, the resulting disability can be accompanied by mild to moderate mood symptoms. This suggests that interventions to improve function, if commenced early in the course of subacute pain, might prevent work disability.

One-year follow-up of first onset low back pain.

Efforts to examine the process and risk of developing chronic back pain have relied generally upon retrospective study of individuals with already established pain. In an alternative approach to understanding the clinical course and evolution of low back disorders, a cohort of 76 men experiencing their first episode of back pain was assessed prospectively at 2, 6 and 12 months following pain onset. Standard measures of pain (Descriptor Differential Scale: DDS), disability (Sickness Impact Profile: SIP), and distress (Beck Depression Inventory: BDI) were employed to classify the sample into five groups: Resolved, Pain Only, Disability/Distress Only, Pain and Mild Disability/Distress, and Clinical Range. At both 6 and 12 months post pain onset, most (78%, 72% respectively) of the sample continued to experience pain. Many also experienced marked disability at 6 months (26%) and 12 months (14%). At 12 months, no participants had worsened relative to the 2-month baseline. Doubly multivariate analyses of variance (MANOVAs) were employed to compare baseline groups (Pain Only, Pain and Mild Disability/Distress, Clinical Range) on the DDS, SIP, and BDI across time. The group by time interaction from 2 through 12 months was reliable, with greatest change occurring in the Clinical Range group in disability and distress; interestingly, the decrease in pain was comparable among all groups. Follow-up tests across measures demonstrated greater change in the early (2-6-month) interval and relative stability in the later (6-12-month) interval. Comparison of those classified as 'improvers' with those who did not improve from 2 to 12 months showed similar findings. The clinical course of first onset back pain may be prolonged for many patients, and involves a continuum of related disability and distress. Individuals at risk for marked symptoms 1 year after an initial episode of back pain can be identified early, and prompt treatment might reduce the risk of pain chronicity.