Negative affect and sleep disturbance may be associated with response to epidural steroid injections for spine-related pain.
OBJECTIVE
To describe whether negative affect and sleep impairment are associated with the clinical effect of epidural steroid injections (ESIs) for low back pain.


METHODS
Observational study; patients were evaluated before ESI and 1 and 3 months after ESI.


METHODS
Spine center and related treatment sites.


METHODS
Participants (N=158) seeking treatment for low back pain with or without radiculopathy.


METHODS
ESI for low back pain with or without radiculopathy.


METHODS
We assessed the dependent (global pain severity for back and leg pain, pain behavior, pain interference) and independent variables (depression, sleep disturbance, and covariates of back pain response) with the Patient-Reported Outcome Measurement Information System (PROMIS) and legacy measures. Outcome was assessed cross-sectionally using multiple regression and longitudinally with path analysis.


RESULTS
After 1 month, sleep disturbance was the only predictor for the global ratings of improvement in back pain (R(2)=16.8%) and leg pain (R(2)=11.4%). The proportions of variance explained by sleep disturbance and negative affect for all dependent variables were greater at 3 months than 1 month. Mediation analysis was significant for negative affect for the 3-month outcomes on PROMIS pain behavior (β=.87, P<.01) and pain interference (β=.37, P<.01). There was no evidence of mediation by sleep disturbance for any outcome.


CONCLUSIONS
Negative affect and sleep disturbance are associated with worse outcomes after ESI. Further research is needed to determine if treatment of negative affect and sleep disturbance prior to or concurrently with ESI will improve outcomes.
Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA; Department of Anesthesiology, University of Pittsburgh School of Medicine, Pittsburgh, PA. Electronic address: karpjf@upmc.edu.
Jordan F
JF
Karp
Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA.
Lan
L
Yu
Department of Rehabilitation, University of Washington, Seattle, WA.
Janna
J
Friedly
Department of Rehabilitation, University of Washington, Seattle, WA.
Dagmar
D
Amtmann
Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA.
Paul A
PA
Pilkonis
D000339:Affect; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007268:Injections, Epidural / Q000009:adverse effects*; D008137:Longitudinal Studies; D017116:Low Back Pain / Q000188:drug therapy*; D008297:Male; D010147:Pain Measurement; D011594:Psychometrics; D011843:Radiculopathy / Q000188:drug therapy*; D012893:Sleep Wake Disorders / Q000209:etiology*; D013256:Steroids / Q000009:adverse effects* / Q000627:therapeutic use*; D011795:Surveys and Questionnaires; D016896:Treatment Outcome
D013256:Steroids
CAT; CES-D; Center for Epidemiologic Studies-Depression; ESI; Low back pain; MOS; Medical Outcomes Study; PROMIS; Patient-Reported Outcome Measurement Information System; RMDQ; Rehabilitation; Roland-Morris Disability Questionnaire; Sciatica; Sleep; computerized adaptive testing; epidural steroid injection