Psychiatric diagnosis receipt after low back pain diagnosis across the US Military Health System and Veterans Health Administration

The objective of this retrospective observational cohort study was to evaluate psychiatric diagnosis receipt after low back pain (LBP) diagnosis across the US Military Health System (MHS) and Veterans Health Administration (VHA). Medical records (N = 197,925) of patients who received a LBP diagnosis March 2021 - March 2022 were analyzed. Primary outcomes were time-to-psychiatric diagnosis and diagnosis type within 1-year post-index LBP diagnosis. In a Poisson generalized additive model, incidence rate ratios (IRRs) of psychiatric diagnosis were higher for patients with a female administrative gender marker (ref. male; 1.40; 95% CI 1.31–1.50); Black (ref. Non-Hispanic White; 1.35; 95% CI 1.29–1.42) and Hispanic (ref. Non-Hispanic White; 1.13; 95% CI 1.06–1.20) patients, and patients with co-occurring non-LBP pain (1.29; 95% CI 1.24–1.33) and nicotine dependence (1.14; 95% CI 1.05–1.25). IRRs were lower for patients with elevated CCI scores (0.89; 95% CI 0.79–1.00) and those diagnosed with obesity (0.91; 95% CI 0.85–0.96). A generalized linear model indicated the adjustment-related versus other psychiatric diagnosis odds ratio (OR) was higher for Black patients (1.18; 95% CI 1.05–1.31) and those with an obesity diagnosis (1.17; 95% CI 1.01, 1.35); and lower for retired service members (0.71; 95% CI 0.58–0.88) and Veterans (ref. active duty service member; 0.59; 95% CI 0.4–0.73), and patients with a female administrative gender marker (0.83; 95% CI 0.71–0.97). The present findings indicate variation in psychiatric diagnoses receipt among patients with LBP across the MHS and VHA, which warrant system-level interventions to improve timing and quality of care. Perspective: Variation across both receipt and type of psychiatric diagnosis in military-connected patients within a year after low back pain diagnosis indicate further inquiry is needed to better understand mediators (e.g., differences in stigma, access to care) and impact of new policies (e.g., the Brandon Act).