429: Is Pain Relief Metabolically Limited? Prospective Outcomes of Lumbar TFESI in Metabolic Syndrome

Topic: Clinical Science
Subtopic: Pain category (ICD-11), Chronic primary musculoskeletal pain, Pain in Special Populations , Treatment/management

Background and Aims: Metabolic syndrome (MS)—defined by central obesity, dyslipidemia, hypertension, and impaired glucose metabolism—has been increasingly linked to chronic pain through systemic inflammatory activity and biomechanical pathways. Despite this relevance, its influence on the clinical effectiveness of lumbar transforaminal epidural steroid injections (TFESI) has not been prospectively evaluated. This study aimed to determine whether metabolic syndrome affects overall treatment success following lumbar TFESI.

Methods: In this prospective cohort study, 51 patients with unilateral lumbar radicular pain underwent standardized fluoroscopy-guided TFESI and were followed for three months. Participants were classified into MS (n = 21) or metabolically healthy (n = 30) groups based on harmonized metabolic syndrome criteria. Pain intensity (numeric rating scale, NRS-11), health-related quality of life (Short Form- 12, SF-12 Physical and Mental Component Scores), and functional disability (Istanbul Low Back Pain Disability Index, ILBPDI) were assessed at baseline, week 3, and month 3. Treatment success was defined as ≥50% reduction in NRS-11, while the minimal clinically important change (MCIC) was defined as a ≥2-point improvement.

Results: Both groups showed significant early improvement in pain and disability by week 3, with no differences between groups at that time point. By month 3, however, patients with MS demonstrated significantly higher NRS-11 scores, lower treatment success rates (33% vs. 73%), lower MCIC achievement (47.6% vs. 90%), and poorer ILBPDI and SF-12 physical component scores compared with metabolically healthy controls. No between-group differences were observed in SF-12 mental component scores.

Conclusions: Metabolic syndrome was associated with less sustained clinical and functional benefit following TFESI. Although short-term analgesic responses were comparable, only metabolically healthy patients maintained improvement through the three-month follow-up. The systemic inflammation, impaired muscle quality, and biomechanical alterations characteristic of MS may limit sustained therapeutic effect. These findings suggest that optimizing metabolic health may serve as an important strategy to improve long-term TFESI outcomes.

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2. Encalada S, Atchison JW, Prideaux CC, Narouze S, et al. The association between chronic pain and metabolic syndrome: A scoping review. Pm r. 2025;17(9):1107-1119
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Presenting Author: Savas Sencan
Submitting Author: Merve Sekizkardes Tutuncu

Senior Author: Savas Sencan

IASP 2026 Global Year theme of Neuropathic Pain: No

• Sinem Ozler: MD - Marmara University School of Medicine
• Serdar Kokar: Associate Professor - Marmara University School of Medicine
• Osman Hakan Gündüz: Professor - Marmara University School of Medicine
• Savas Sencan: Associate Professor - Marmara University School of Medicine