Association between Sleep Quality and Non-Vertiginous Dizziness: A Hospital-Based Case-Control Study

Seo, Il Kyo; Choi, Yun Im; Jeong, Du Shin; Park, Hyung Kook; Hwangbo, Young; Yang, Kwang Ik

Abstract

OBJECTIVES
Poor sleep quality can impair daytime function and evoke fatigue and excessive daytime sleepiness. Dizziness is one of the common subjective complaints and attributed to various medical and neuropsychological disorders. But influence of poor sleep quality on dizziness has not been fully studied. We hypothesized the patients with poor quality of sleep might feel non-vertiginous dizziness (NVD). The aim of this study is to investigate the association between sleep quality and development of NVD.
METHODS
We recruited 106 patients who had presented NVD in neurology department of Soonchunhyang University Cheonan Hospital from July 1st, 2009 to June 30th, 2010. They completed the following questionnaires: the Pittsburgh Sleep Quality Index (PSQI), the Insomnia Severity Index (ISI), the Fatigue Severity Index, the Epworth Sleepiness Scale, Sleep Apnea scale of the Sleep Disorders Questionnaire and Beck Depression Inventory (BDI). 116 dizziness-free controls were recruited via Health Screening Center and also completed the same questionnaires.
RESULTS
Patient with NVD had significantly higher PSQI and ISI score compared with the controls (PSQI: 7.7+/-4.4 vs. 5.4+/-2.6, p<0.001, ISI: 9.7+/-7.0 vs. 6.8+/-4.4, p<0.001). In multiple logistic regression analysis adjusted for age, sex, body mass index, and BDI, poor sleep quality was significantly associated with NVD. Fully adjusted odds ratio (OR) for NVD associated with 1 unit increase in PSQI was 1.15 [95% confidence interval (CI): 1.04-1.26]. Insomnia (ISI> or =15) was significantly associated with NVD (OR=4.43, 95% CI: 1.66-11.81).
CONCLUSIONS
This study suggests that the poor quality of sleep is associated with NVD.