A retrospective cohort analysis of the effects of renin-angiotensin system inhibitors on spinal fusion in ACDF patients

Recently, preclinical and clinical studies suggest an association between renin-angiotensin system (RAS) blockers and bone healing, particularly in the context of osteoporotic bone fractures. To determine the correlation between the use of RAS inhibitors and fusion outcomes and neurologic status in anterior cervical discectomy and fusion (ACDF) surgery. Retrospective observational study. Patients who underwent ACDF for degenerative disorders. Spinal fusion status and neurologic function (modified Japanese Orthopedic Association [mJOA] and Nurick grading scales). A retrospective chart review was performed, including 200 patients who underwent ACDF for degenerative disorders with 1-year minimum follow-up. Demographic data, comorbidities, antihypertensive medication, neurologic examination, and fusion status were collected. Spinal fusion was assessed via plain cervical x-ray, resorting to dynamic radiographs and/or computer tomography (CT) in cases of uncertainty. Preoperative mJOA and Nurick scores and recovery rates were calculated to determine neurologic status. Of the 200 patients (42.5% females, 57.5% males, median age of 53.7 years), 82 hypertensive patients were identified. Seventy-seven (93.9%) were taking antihypertensive medication as follows: 36.4% angiotensin-II receptor blockers (ARBs), 35.1% angiotensin-converting enzyme inhibitors (ACEIs), and the remaining patients were taking other medication. In the analysis of fusion rates, patients treated with ARBs exhibited a higher fusion rate, while those treated with ACEIs displayed a lower fusion rate compared to untreated nonhypertensive patients (p = .04 and .02, respectively). The difference in fusion rates between ARBs and ACEIs was also significant, with the former displaying higher rates (p