Relationship of Opioid Prescriptions to Physical Therapy Referral and Participation for Medicaid Patients with New-Onset Low Back Pain

Abstract

Introduction: Physical therapy (PT) early in the management of low back pain (LBP) is associated with reductions in subsequent health care utilization and LBP-related costs. The objectives of this study were to 1) Examine differences among newly consulting patients with LBP who received a PT referral and those who did not, 2) examine differences between patients who participated in PT to those who did not, and 3) compare the impact of a PT referral and PT participation on LBP-related health care utilization and costs over 1 year.

Methods: This was a retrospective cohort study using electronic medical records and claims data. Participants were 454 Medicaid enrollees with new LBP consultations (mean age, 40.4 years; SD = 12.0; 70% women). Outcomes included advanced imaging, injections, emergency department visits, opioid prescriptions, surgery and LBP-related costs. Variables associated with a PT consult, PT participation, and subsequent outcomes were evaluated with multivariate models.

Results: A total of 251 (55%) participants received a PT consult within 7 days of the index LBP visit and 81 (19%) participated in PT. The odds of a PT consult were increased if patients were prescribed non-steroidal anti-inflammatories (aOR = 1.81; 95% confidence interval [CI], 1.0 to 3.27; P = .05) or muscle relaxers (adjusted odds ratio [aOR] = 2.24; 95% CI, 1.03 to 4.87; P = .04). Whereas tobacco users and individual with multiple comorbidities were less likely to receive a PT consult (aOR = 0.52; 95% CI, 0.20 to 0.91) and 0.42 (95% CI, 0.23 to 0.78), respectively). Odds of participating in PT were higher for patients receiving an radiograph at baseline (odds ratio [OR] = 2.63; 95% CI, 1.25 to 5.53) or having multiple comorbidities (OR = 2.96; 95% CI, 1.20 to 7.20). The odds of receiving an opioid prescription over the year following the index visit reduced with a PT consult (aOR = 0.65; 95% CI, 0.43 to 1.00) and with PT participation (aOR = 0.47; 95% CI, 0.24 to 0.92). No differences in LBP related costs over 1 year were noted between any of the groups.

Conclusions: Among Medicaid recipients with new-onset LBP, the index provider's prescription and imaging decisions and patient demographics were associated with PT referrals and participation. A referral to PT and subsequent PT participation was associated with reduced opioid prescriptions during follow-up. There was no difference in overall LBP-related health care costs.

Keywords: Back Pain; Health Services; Opioid Analgesics; Physical Therapy Modalities.