232. Inhibition of neurogenic inflammatory pathways associated with reduction in discogenic back pain

BACKGROUND CONTEXT

Calcitonin gene-related peptide (CGRP), a neuropeptide found in abundance at the interface between blood vessels and sensory nerve fibers, upregulates pro-inflammatory cytokines including tumor necrosis factor-α, interleukin-6, brain derived neurotrophic factor, and nerve growth factor in spinal spondylotic disease resulting in disc degeneration and sensitization of nociceptive neurons. While the new class of anti-CGRP medications have proven ability to quell neurogenic inflammation in migraines, their off-site efficacy as a therapeutic target for discogenic back/neck pain conditions remains unknown.

PURPOSE

Utilizing a patient population with comorbid degenerative spinal disease and migraines, this study aims to determine if initiation of anti-CGRP biologic treatment for migraines was also associated with improvements in back/neck pain, mobility, and function.

STUDY DESIGN/SETTING

Retrospective case series.

PATIENT SAMPLE

All patients over age 18 with concomitant spinal spondylosis and migraine diagnoses treated with anti-CGRP medications at a single academic institution between 2017-2020 were retrospectively identified. Patients with history of spinal surgery, malignancy, cervicogenic headache, new narcotic prescriptions or inconsistent anti-CGRP use were excluded.

OUTCOME MEASURES

Clinical spine outcomes before and after anti-CGRP medication initiation including pain, mobility and functional status.

METHODS

Patient demographic (age, sex, race, smoking status, BMI) and medical (CCI, depression, anxiety, fibromyalgia) data, follow-up duration, migraine severity and frequency, spine pain, functional status, and mobility before and after anti-CGRP medication initiation were collected. Paired univariate analysis tested for significant changes in spine pain, headache severity, and headache frequency before and after beginning anti-CGRP. Correlation between changes in spine pain score and functional or mobility improvement were assessed with the Spearman's rho coefficient.

RESULTS

A total of 56 patients were included. The mean follow-up time after anti-CGRP initiation was 123 days for spine visits and 129 days for migraine visits. Back/neck pain decreased significantly (p<0.001) from 6.30 to 4.36 after starting anti-CGRP medication for migraine control. As recorded in the spine follow-up notes, 25% of patients experienced functional improvement in ADLs and 17.5% of patients experienced mobility improvement while taking anti-CGRP medication. Change in back/neck pain demonstrated a moderate correlation (ρ= -0.430) with functional improvement but no correlation with mobility improvement (ρ= -0.052).

CONCLUSIONS

Patients receiving anti-CGRP treatment for chronic migraines with comorbid degenerative spine conditions experienced significant off-target back/neck pain reduction. Future interventional studies are necessary to explore the effectiveness of this novel medication class in all patients with discogenic back/neck pain that is recalcitrant to standard nonoperative therapies.

FDA DEVICE/DRUG STATUS

This abstract does not discuss or include any applicable devices or drugs.