Study design: Prospective, longitudinal, observational cohort design.
Objective: The primary aim was to examine the association between changes in psychosocial distress (PD), and functional status (FS) and pain intensity at discharge from physical therapy.
Background: Patients with lumbar impairments seeking physical therapy commonly demonstrate elevated PD. However, it is not clear if PD changes that occur during physical therapy management are associated with improved clinical outcomes.
Methods: Data from adults (n = 692) with lumbar impairment were analyzed. Patients were screened using the Symptom Checklist Back Pain Prediction Model questionnaire (SCL BPPM) to identify patients at intake and discharge into 3 levels of risk for persistent disability (high, intermediate, or low). SCL BPPM classifications allowed for 5 patterns of change in PD during therapy (decreased, stable low, stable intermediate, stable high, or increased). Associations between PD change patterns and discharge FS and pain intensity were assessed using multivariable linear regression models, controlling for selected risk-adjustment variables.
Results: Proportions of patients classified by patterns of PD change for decreased, stable low, stable intermediate, stable high, and increased were 0.34, 0.52, 0.05, 0.06, and 0.03, respectively. Compared to the decreased PD group, (1) increased, stable high, and stable intermediate PD patterns were associated with worse discharge FS scores (-7.9 [95% CI: -13.5, -2.21], -10.9 [95% CI: -15.25, -6.49], and -8.9 [95% CI: -13.65, -4.21] units, respectively), and (2) stable high and stable intermediate PD patterns were associated with higher pain intensity (2.59 [95% CI: 1.81, 3.56] and 2.14 [95% CI: 1.25, 3.04] units, respectively).
Conclusions: Lower FS and higher pain intensity outcomes were associated in similar but not identical patterns with patients whose SCL BPPM classification of PD increased, or remained at high or intermediate levels during physical therapy. Serial assessments of change in PD during rehabilitation are recommended as a possible treatment-monitoring tool.