Correlation analysis between aromatase inhibitor and lumbar intervertebral disc degeneration: a case-control study

Abstract Background: Hormone level is an important factor affecting intervertebral disc degeneration (IVDD). Aromatase inhibitors (AI) can reduce the production of estrogen in peripheral tissues by inhibiting the activity of aromatase. The objective of this study is to investigate the correlation between AI as endocrine therapy and IVDD in postoperative patients with breast cancer.Methods: Postmenopausal breast cancer patients treated in the Third Hospital of Hebei Medical University after surgery were retrospectively analyzed. Patients' age, height, weight, menstrual history, basic diseases, postoperative history, postoperative chemotherapy plan and imaging data were collected. Patients were devided into the AI group and the non-AI group according to whether AI were used or not. IVDD was assessed by measuring lumbar lordosis (LL), vertebral CT density, lumbar disc height index (DHI), and modified Pfirrmann grading system. SPSS 20 was used for statistical analysis.Results: A total of 68 patients were included in the study, including 40 patients in the AI group and 28 patients in the non-AI group. No significant differences were present in age, body mass index (BMI), prevalence of basic diseases, postoperative history, LL and vertebral CT density between the AI group and the non-AI group. Lumbar DHI of L1/2, L2/3 and L3/4 in the non-AI group was higher than that in the AI group (P = 0.001, P = 0.010 and P = 0.010, respectively). But the comparisons of L4/5, L5/S1 DHI and average DHI between the two groups were not significant (P > 0.05). The modified Pfirrmann grading of L1/2, L2/3, L3/4 and L4/5 in AI group was higher than that in non-AI group (P=0.001, P=0.017, P=0.005 and P=0.004, respectively). However, the comparison of L5/S1 modified Pfirrmann grading between the two groups was not significant (P > 0.05).Conclusions: This study indicates that there may be a positive correlation between the use of AI and lumbar IVDD, which is significant in the upper lumbar spine (L1/2-L3/4).