Low back pain service utilization and costs: association with timing of first-line services for individuals initially contacting a physician specialist. A retrospective cohort study

Abstract

Background: Physician specialists (PS) are often the type of healthcare provider initially contacted by an individual with low back pain (LBP). LBP clinical practice guidelines (CPG) recommend a stepped approach to management with an emphasis on first-line non-pharmaceutical and non-interventional services. Objective: Examine the association between the incorporation of CPG recommended first-line services, exposure to second- and third-line services and total episode cost for individuals with non-surgical LBP initially contacting a PS. Design: Retrospective observational study with identical design to previous study focused on primary care physicians. Setting/Patients: National sample of individuals with non-surgical LBP occurring in 2017-2019. Measurements: Independent variables were initial contact with a PS, and the timing of incorporation of five types of first-line services. Dependent measures included exposure to thirteen types of health care services and total episode cost. Results: 91,096 individuals were associated with 98,992 episodes of non-surgical LBP. 36.2% of the 33,277 PS initially contacted for an episode of LBP incorporated any first-line service at any time during an episode. A first-line service was provided in 24.0% of episodes with active care (19.5% of episodes), manual therapy (13.7%) and chiropractic manipulative therapy (6.5%) the most common. 7.3% of non-surgical LBP episodes included a first-line service within seven days of initial contact with a PS. These episodes were associated with a reduction in the use of prescription skeletal muscle relaxants (risk ratio 0.88) and opioids (0.55), spinal injections (0.84), and CT scans (0.71), with no impact on the use of prescription NSAIDs, radiography, or MRI scans. First-line services were associated with an increase in total episode cost at any time of incorporation with chiropractic manipulation associated with the lowest cost increase. Younger individuals from zip codes with higher adjusted gross income were more likely to receive a first-line service in the first seven days of an episode. Limitations: As a retrospective observational analysis of associations there are numerous potential confounders and limitations. Conclusions: Individuals with non-surgical LBP initially contacting a PS infrequently receive a CPG recommended first-line service. If a first-line service is provided it is often later in an episode and typically in addition to second- and third-line services. There is an opportunity to improve concordance with LBP CPGs for individuals with LBP initially contacting a PS.