Primary and Secondary Benign Paroxysmal Positional Vertigo due to Peripheral Acute Vestibular Syndrome: A Case-Control Study

Introduction and Objective: The aim of our study was to demonstrate the clinical differences between idiopathic benign paroxysmal positional vertigo (BPPV) and BPPV secondary to acute peripheral vestibular syndrome (APVS). Method: Retrospective case -control study. Data collection was obtained from medical records at our hospital. Demographic and clinical data of patients diagnosed with idiopathic BPPV and BPPV secondary to APVS were collected for analysis. Additionally, in the case group, a correlation was performed between peripheral vestibular deficit, measured through the video head impulse test (vHIT), and the number of maneuvers and time until resolution of BPPV. Results: Seventy-two patients were included, with 64% being women. The control group included 50 patients with idiopathic BPPV and 22 with BPPV secondary to APVS in the case group. In secondary BPPV, the posterior semicircular canal was affected in 100% of cases (OR: 1.2; 95% CI [1.088 - 1.436]). Both groups showed a vertigo resolution rate of 90% and 89%, respectively. The secondary BPPV group had a 4 -fold higher recurrence risk (OR: 4.18; 95% CI [1.410 - 12.406]); they required more maneuvers (3.32 +/- 2.2 vs. 1.7 +/- 1.3, p = 0.004) and more time (61.9 days +/- 73.1 vs. 12.9 days +/- 9.6, p = 0.007) for BPPV resolution. Significant correlations were found between the difference in mean gain of the vestibulo-ocular reflex (VOR) and the number of maneuvers (r = 0.462, p = 0.030) and the time until resolution (r = 0.577, p = 0.008). Discussion: Clinical differences exist between idiopathic BPPV and BPPV secondary to APVS, primarily in terms of the affected semicircular canal, a higher number of maneuvers, and a longer time in days until BPPV resolution. Furthermore, it was determined that a greater vestibular deficit in a patient with secondary BPPV to APVS requires a higher number of maneuvers and an extended time until BPPV resolution. Conclusions: BPPV secondary to APVS presents a higher risk of recurrence, requires a greater number of maneuvers, and takes longer to resolve compared to idiopathic BPPV.