The Association of Operative versus Nonoperative Treatment for Lumbar Spondylolisthesis and Stenosis with Future Metabolic Conditions and Allostatic Burden: An Emulated Target Trial

Abstract

Background context: Lumbar spinal stenosis adversely impacts mobility and function. Persistent lack of exercise and ambulatory capacity may contribute to the development of metabolic conditions.

Purpose: To determine the effect of surgical intervention, as compared to non-operative treatment, on the development of metabolic conditions, chronic pain, frailty, and allostatic load (AL).

Study design: Retrospective emulation target trial.

Patient sample: 2,521,827 patients were included, of which 329,314 (13.1%) underwent surgery.

Outcome measures: Development of metabolic conditions, chronic pain, frailty, and allostatic load (AL).

Methods: Data was sourced from EPIC COSMOS. We conducted a clone analysis using inverse probability censoring weights and inverse probability of treatment weights that accounted for confounders. Risk ratios (RR) were calculated at 1- and 3-years post-index diagnosis for post-operative metabolic burden and frailty, and at 1 and 2 years for active opioid prescription, using weighted pooled logistic regression. Generalized Estimating Equation was used to determine the mean difference in AL at 1 and 3 years.

Results: Surgery within 12 months of index diagnosis demonstrated a significantly lower risk of metabolic burden (1-year RR [95% confidence interval (CI)]: 0.98 [0.98 - 0.98]; 3-year: 0.98 [0.98 - 0.98]) and frailty (1-year: 0.98 [0.98 - 0.99]; 3-year: 0.99 [0.98 - 0.99]). The risk of metabolic burden was lowest if surgery occurred within 6 months (1-year RR [95% CI]: 0.93 [0.93 - 0.94]; 3-year RR [95% CI]: 0.94 [0.94 - 0.95]). No significant difference in AL was noted at 1-year, and the difference was negligible at 3-years. The surgery cohort had a higher risk of active opioid prescription at 1-year (RR [95% CI]: 1.04 [1.04 - 1.04]) and 3-year (RR [95% CI]: 1.19 [1.17 - 1.20]) follow-up.

Conclusions: We found that surgical intervention was associated with greater reductions in metabolic burden and frailty up to three years following the procedure. We also found evidence of a time-dependent effect such that maximal benefit was appreciated when surgery was performed within 6-months of presentation.

Keywords: allostatic burden; emulated target trial; lumbar spinal stenosis; metabolic syndrome; non-operative management; surgery.