Benign paroxysmal positional vertigo (BPPV) is the most common peripheral vestibular disorder. Although the pathophysiology of BPPV is mainly attributed to the displacement of otoconia within the semicircular canals, recent studies suggest that psychological stress and anxiety may be associated with the onset or recurrence of the disease. However, the biological mechanisms underlying this relationship remain poorly understood, and objective evaluation of autonomic nervous system function in patients with BPPV is limited.

Heart rate variability (HRV) is a non-invasive method widely used to assess autonomic nervous system activity. Short-term HRV measurements provide information about autonomic balance and vagal tone. In particular, parameters such as the root mean square of successive differences (RMSSD) and the coefficient of variation of RR intervals (COV RR/R) are considered indicators of parasympathetic activity.

The aim of this prospective case-control study is to evaluate vagal tone in patients with BPPV using short-term HRV analysis and to compare the findings with age-, sex-, and body mass index-matched healthy controls. Participants will undergo standardized HRV measurements at rest and during controlled breathing. Perceived stress levels will also be assessed using the Perceived Stress Scale (PSS-10).

The primary outcomes of the study are RMSSD and the coefficient of variation of RR intervals (COV RR/R), obtained from short-term HRV recordings. These parameters will be compared between BPPV patients and healthy controls, and their associations with perceived stress levels will also be explored. The findings of this study may provide insights into the role of autonomic regulation and stress-related mechanisms in the pathophysiology of BPPV.

Inclusion Criteria:

• BPPV Group

Age 18 years or older

Clinical diagnosis of benign paroxysmal positional vertigo (BPPV) confirmed by positional testing (Dix-Hallpike and/or Roll test) with positional nystagmus

No known history of cardiac disease

Ability and willingness to provide written informed consent

Healthy Control Group

Age 18 years or older

No history of vertigo or known vestibular disorder

Age- and sex-matched to the BPPV group

No known history of cardiac disease

Ability and willingness to provide written informed consent

Exclusion Criteria:

• Age younger than 18 years

Inability to provide informed consent or impaired mental capacity

Known arrhythmia, heart failure, ischemic heart disease, or other clinically significant cardiac disorder

Use of medications that may directly affect heart rate variability, including beta-blockers, non-dihydropyridine calcium channel blockers, antiarrhythmic drugs, digoxin, systemic corticosteroids, centrally acting sympatholytic agents, or psychotropic medications that may influence autonomic balance

Active infection or systemic inflammatory disease

The study population will consist of adult patients presenting to the otolaryngology outpatient clinic of Istanbul Aydın University Hospital with complaints of vertigo and diagnosed with benign paroxysmal positional vertigo (BPPV) based on clinical evaluation and positional testing (Dix-Hallpike and/or Roll test). The control group will include age- and sex-matched healthy volunteers without a history of vertigo or vestibular disorders. All participants will be recruited from individuals attending the same hospital during the study period.