Korean J Otorhinolaryngol-Head Neck Surg.  2008 Nov;51(11):1020-1024.

The Consequence of Cardiovascular Sympathetic Nervous System in Obstructive Sleep Apnea

• Jung JH
• Kim SY
• Yoon BK
• Kang IG
• Kim ST
• Park KH

Abstract

BACKGROUND AND OBJECTIVES: The previous studies have shown that patients with obstructive sleep apnea (OSA) have shown high levels of cardiovascular diseases. These cardiovascular diseases are related to imbalance of cardiac autonomic systems. Alteration of QT interval in EKG reflects the increased cardiac sympathetic activity. The purpose of this study is to compare the cardiac sympathetic nerve activity between the control and OSA patients.
SUBJECTS AND METHOD
All the patients were divided into the control group (n=20), whose RDI was less than 5 and the OSA group (n=40), whose RDI was more than 5. The OSA group was also divided into 3 groups, mild, moderate and severe, according to their RDI. The corrected QT interval (QTc) in EKG was checked at day time and during polysomnography.
RESULTS
The number of hypertensive patients was significantly greater in the OSA group than the control group (p<0.001). The QTc interval was increased proportional to the RDI (p<0.001). There was a significant difference in the QTc intervals between the daytime period and apnea peak (p=0.031).
CONCLUSION
Our results showed that the QT prolongation might be a prognostic factor in predicting the cardiac sympathetic hyperactivity in obstructive sleep apnea patients.

Keyword

Obstructive sleep apnea; Respiratory distress index; QT interval

MeSH Terms

Apnea
Cardiovascular Diseases
Electrocardiography
Humans
Polysomnography
Sleep Apnea, Obstructive
Sympathetic Nervous System