Patients and methods: A total of 156 postmenopausal women (mean age: 59.5±7.4 years; range, 46 to 75 years) diagnosed with primary BPPV between January 2015 and August 2018 were included. After follow-up for one year, they were divided into non-recurrence (n=126) and recurrence groups (n=30). Fifty healthy females (mean age: 60.3±7.4 years; range, 48 to 75 years) with natural menopause for over one year were enrolled as the control group. Serum estradiol, calcium and 25(OH)D levels were compared, and their correlations in the recurrence group were analyzed by Pearson method. The predictive values of these levels for recurrence were evaluated using the receiver operating characteristic curve. Predisposing factors were determined by univariate and multivariate logistic regression analyses.

Results: Serum estradiol, calcium, and 25(OH)D levels of the control group were significantly higher than the non-recurrence and recurrence groups (p<0.05). The levels of recurrence group exceeded those of non-recurrence group (p<0.05). In recurrence group, estradiol level was positively correlated with those of calcium and 25(OH)D (r=0.7501, 0.7871, p<0.001), and calcium level was positively correlated with that of 25(OH)D (r=0.7904, p<0.001). The three levels had diagnostic values for recurrence. The maximum Youden`s index of their combination was 0.476, and the corresponding prognostic index was 13.04, suggesting a higher recurrence probability. Number of repositioning, Self-Rating Depression Scale score, levels of estradiol, calcium and 25(OH)D were predisposing factors for recurrence.

Conclusion: Serum estradiol, calcium, and 25(OH)D levels are significantly positively correlated in postmenopausal women with BPPV recurrence and their combination can be used to predict recurrence. Keywords : 25-hydroxyvitamin D, benign paroxysmal positional vertigo, calcium, estradiol, postmenopause