The associations between hypertension, diabetes, and dyslipidemia with Bell’s palsy have been controversial and only a few studies have assessed risk factors for Bell’s palsy based on population-based data. The aim of the present study was to evaluate whether sociodemographic factors such as sex, age, residence, household income, and metabolic diseases such as hypertension, diabetes, and dyslipidemia were risk factors for Bell’s palsy using the National Health Insurance Service National Sample Cohort data of Korea. Patients who visited an outpatient clinic twice or more or had one or more admission and received steroid medication under the International Classification of Diseases diagnostic codes for Bell’s palsy from 2006 to 2015 were defined as patients with Bell’s palsy in this study. The associations between sociodemographic factors and metabolic diseases to Bell’s palsy were analyzed with univariate and multivariate Cox proportional hazard regression models. There were 2708 patients with Bell’s palsy recorded from 2006 to 2015. Male sex, advanced age, residence in a location other than the capital and metropolitan cities, hypertension, and diabetes were significant risk factors for Bell’s palsy. This study is significant for patients and providers because we analyzed the relationships using a population-based database over a long-term follow-up period.

BACKGROUND: Several studies on seasonal variation in benign paroxysmal positional vertigo (BPPV) have been reported. However, the association between season and BPPV remains controversial; thus, further study is required. OBJECTIVE: We analyzed patients with BPPV to evaluate monthly and seasonal variations. METHODS: Patients with BPPV seen between 2013 and 2017 were retrospectively enrolled in this study. Differences among the months and seasons of BPPV visits were analyzed. Patients were divided into two groups according to age (65 years or older and younger than 65 years) and sex, respectively, and the differences were analyzed in each group. RESULTS: There was no significant difference in the monthly or seasonal distribution of BPPV in the 1,216 patients. There was also no significant difference in the monthly or seasonal distribution in the older and younger groups or in male and female patients. CONCLUSIONS: There was no significant difference in the monthly or seasonal distribution of patients with BPPV. Additional studies on seasonal variation in BPPV are required in terms of not only vitamin D levels but also other associated factors.

Seasonal variations in vestibular neuritis (VN) could support the etiology of viral infection. However, several recent studies revealed no significant seasonal variations in VN. Further studies are necessary to determine the etiology of VN. We analyzed patients with VN to evaluate monthly and seasonal variations. Patients with VN who visited our otorhinolaryngology department or were referred to our department from the emergency department between March 2014 and February 2019 were included retrospectively in this study. Differences among the months and seasons of VN visits were analyzed. Patients were divided into 2 groups according to sex and age (65 years or older and younger than 65 years). Differences among the months and seasons of VN visits were analyzed between groups. There were no significant differences in monthly and seasonal distributions in 248 patients with VN. There were also no significant differences in monthly and seasonal distributions in male and female patients or in older and younger patients. There were no significant differences in monthly or seasonal distributions of patients with VN. Factors other than viruses, such as vascular ischemia, should also be considered in the incidence of VN, especially in older patients.