Evaluation of Risk Factors Associated with the Occurrence and Recurrence of Benign Paroxysmal Positional Vertigo in Koreans: A Nested Case-Control Study.

Objectives: Benign paroxysmal positional vertigo (BPPV) is the most prevalent cause of vertigo. This study analyzes the risk factors involved in the occurrence and recurrence of BPPV.

Methods: A database maintained by the Korean National Health Insurance Service (NHIS) was used to enroll 434,552 patients diagnosed with BPPV from 2011 to 2017. A propensity score was used to match participants with an equal number of control patients without BPPV by age, sex, residential status, and socioeconomic status. Recurrence of BPPV was defined as an occurrence of BPPV more than 90 days after treatment. Logistic regression was used to analyze the occurrence of BPPV, and Cox proportional hazards models were applied to analyze the risk factors for recurrence.

Results: BPPV was 2.2 times more common in females, peaking between the ages of 50 and 59 years. The five-year BPPV recurrence rate was 39.8%, with a significant portion recurring within the first year. The incidence of BPPV was statistically significantly associated with several underlying medical conditions, including vitamin D deficiency, thyroid hormone abnormalities, head trauma, and disorders of the inner ear. Advanced age, female gender, rural residence, low socioeconomic status, and the presence of inner-ear diseases were notable risk factors for the recurrence of BPPV.

Conclusion: Our study provides significant insight into the risk factors associated with both the occurrence and recurrence of BPPV, which appears to be linked to vitamin D levels, thyroid hormones, and estrogen. Conditions such as inner-ear disorders, head trauma, and otologic surgery were strongly associated with both the occurrence and recurrence of BPPV.