Abdominal aortic calcification is independently associated with lumbar endplate degeneration.

Abstract

Abdominal aortic calcification (AAC) is associated with lower back pain, reduced bone mineral density of the spine. Vascular changes could also affect the already sparsely perfused intervertebral endplate and intervertebral disc. Lumbar MRIs and lateral radiographs of patients with lower back pain were retrospectively analyzed. AAC was assessed on lateral lumbar radiographs according to the Kauppila score, with a maximum score of 24. Patients were grouped into no (AAC = 0), moderate (AAC 1 to ≤ 4), and severe AAC (AAC ≥ 5). Endplate and disc degeneration were classified according to the total endplate score (TEPS) and Pfirrmann classification. The associations between AAC and degenerative changes was analyzed with a generalized mixed model and was adjusted for age, sex, body mass index as well as diabetes mellitus, and smoking status. A total of 217 patients (47.9% female) were included in the analysis, totaling 1085 intervertebral levels. Of those, 45 (20.7%) patients had moderate, and 39 (18%) had severe AAC. The results of the generalized mixed model showed no significant association between AAC and disc degeneration (p > 0.05). In contrast, a significant positive association between AAC and the severity of TEPS (β: 0.51, 95% CI: 1.92-2.12, p = 0.004) was observed in the multivariable analysis. This study demonstrates an independent association between AAC and endplate degeneration. These findings expand our knowledge about the degenerative cascade of the lumbar spine and suggest that AAC might be a modifiable risk factor for endplate changes.