Functional Somatic Syndromes Are Associated With Varied Postoperative Outcomes and Increased Opioid Use After Spine Surgery: A Systematic Review

Study Design Systematic Review Objective To perform a systematic review assessing the relationship between functional somatic syndromes (FSSs) and clinical outcomes after spine surgery. Methods A systematic review of online databases (PubMed and Web of Science) through December 2021 was conducted via PRISMA guidelines to identify all studies investigating the impact of at least one FSS (fibromyalgia, irritable bowel syndrome (IBS), chronic headaches/migraines, interstitial cystitis, chronic fatigue syndrome, multiple chemical sensitivity) on outcomes after spine surgery. Outcomes of interest included patient reported outcome measures (PROMs), postoperative opioid use, cost of care, complications, and readmission rates. Results A total of 207 records were identified. Seven studies (n = 40,011 patients) met inclusion criteria with a mean MINORS score of 16.6 out of 24. Four studies (n = 21,086) reported postoperative opioid use; fibromyalgia was a strong risk factor for long-term opioid use after surgery whereas the association with chronic migraines remains unclear. Two studies (n = 233) reported postoperative patient reported outcome measures (PROMs) with mixed results suggesting a possible association between fibromyalgia and less favorable PROMs. One study (n = 18,692) reported higher postoperative complications in patients with fibromyalgia. Conclusion Patients with fibromyalgia and possibly migraines are at higher risk for prolonged postoperative opioid use and less favorable PROMs after spine surgery. There is limited research on the relationship between other Functional somatic syndromes (FSSs) and outcomes following spine surgery. Growing evidence suggests the variation in outcomes after spine procedures may be attributed to non-identifiable organic patient factors such as FSSs.