The Effect of Serum Vitamin D Normalization in Preventing Recurrences of Benign Paroxysmal Positional Vertigo: A Case-Control Study

Background: benign paroxysmal positional vertigo (bppv) is a condition with recurrent attacks in a significant proportion of patients. the present case- control study was conducted to assess the influence of serum vitamin d normalization on recurrent attacks of vitamin d deficient patients. methods: diagnosis of bppv was made based on history and clinical examination and exclusion of other conditions. serum 25-hydroxy vitamin d (25-ohd) was measured using elisa method and a levels of < 20 ng/ml was considered a deficiency of vitamin d. inclusion criteria were as follows: history of recurrent attacks and serum 25-ohd < 20.ng/ml. while the patients with history of trauma,surgery and chronic systemic diseases were excluded. the patients were classified into two groups: treatment and control,intermittently. both groups received epley rehabilitation therapy one session per week for 4 weeks but the treatment group received an additional supplement of 50.000 iu of vitamin d (cholecalciferol) weekly for two months to achieve serum 25-ohd ≥ 30 ng/ml and the study patients were followed-up for 6 months. results: twenty-seven patients were allocated to each group. at baseline,serum 25-ohd was similar (10.7±2.3 vs 11.41±1.9,p=0.23). at month 2,serum 25-ohd in the treatment group increased significantly to ≥ 30 ng/ml,whereas serum 25-ohd in the control group remained unchanged (34.2±3.3 vs 10.6 10.6±2.2 ng/ml,p=0.001). during the follow-up period,attacks of bppv in the treatment group decreased significantly compared with the control group (14.8% vs 96.3% or= 0.18,p=0.001). conclusion: the findings of this study indicate that the normalization of serum vitamin d significantly reduces bppv recurrences.