Bidirectional Association Between Peripheral Vestibular Disorders and Depressive Disorders: A Longitudinal Follow-Up Study.

Background: An increasing body of evidence indicates that peripheral vestibular disorders (PVDs) are associated with depressive disorders. However, further investigation is required to elucidate the temporal and causal relationships between the aforementioned disorders.

Objective: To clarify the bidirectional association between peripheral vestibular disorders and depressive disorders.

Methods: The present retrospective cohort study used data from the Taiwan National Health Insurance Research Database for the period from January 1, 1998, to December 31, 2013. The study examined PVD and its subtypes as both the cause and consequence of depressive disorders. We collected data from patients diagnosed with either PVDs (N = 87,277) or depressive disorders (N = 87,387) between 1998 and 2011 and from their corresponding controls (1:2 ratio). Cox regression models were employed to evaluate the likelihood of developing depressive disorders or PVDs in patients with prior PVDs or depressive disorders, respectively.

Results: Patients with PVDs had a 4.29-fold (95% confidence interval: 3.93-4.68) higher risk of developing depression. Subgroup analyses based on PVD subtypes revealed that all 4 PVD subtypes (benign paroxysmal positional vertigo, Meniere's disease, vestibular neuritis, and unspecified PVD) predicted higher risks of depressive disorders (hazard ratio: 3.89-5.18). Similarly, individuals with depressive disorders exhibited a 3.29-fold (95% confidence interval: 3.05-5.13) higher risk of developing PVDs.

Conclusions: The 2 cohort studies revealed a bidirectional relationship between PVDs and depression. Further research is required to establish if these 2 conditions have common pathogenic mechanisms and if treating one effectively reduces the morbidity rate of the other.