Association of Plasma Homocysteine with Self-Reported Sleep Apnea Is Confounded by Age: Results from the National Health and Nutrition Examination Survey 2005-2006

Tushar P Thakre,Hemant Kulkarni,Shweta Ujaoney,Manju Mamtani

doi:10.1155/2012/634920

Abstract

High levels of plasma homocysteine are implicated in the pathogenesis of cardiovascular diseases especially if accompanied by sleep apnea, but a direct pathogenetic link between plasma homocysteine levels and obstructive sleep apnea is debatable. This association can have far-reaching public health implications considering the inverse association between folate and plasma homocysteine. We used data from the 2005-2006 cycle of the National Health and Nutrition Examination Survey (NHANES) to test the hypothesized associations. Of the 4490 subjects included in analysis, 177 reported sleep apnea. Age-standardized and design-effect-corrected prevalence rates were differential across gender, plasma homocysteine, and red cell folate status. Plasma homocysteine was positively correlated with age (r = 0.38, P < 0.0001). Multivariate analyses using sociodemographic and clinical covariates demonstrated that plasma homocysteine levels retained their respective associations with self-reported sleep apnea in all models except when age was included as a covariate. Our results demonstrate that the claimed association of plasma homocysteine with sleep apnea may be confounded by age.

Highlights

Obstructive sleep apnea (OSA)—a disorder in which a person frequently stops breathing during sleep—results from an obstruction of the upper airway that occurs because of inadequate motor tone of the tongue and/or airway dilator muscles
The National Health and Nutrition Examination Survey (NHANES) is an annual survey conducted by the National Center of Health Statistics (NCHS) of the Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, USA
Severity of OSA is associated with increased homocysteine levels in subjects with ischemic heart disease

Summary

Introduction

Obstructive sleep apnea (OSA)—a disorder in which a person frequently stops breathing during sleep—results from an obstruction of the upper airway that occurs because of inadequate motor tone of the tongue and/or airway dilator muscles. In the United States, the prevalence of OSA is estimated to be 3–7% in men and 2–5% in women [1]. Up to 93% of women and 82% of men may already have an undiagnosed moderate to severe OSA [2]. Of greater interest and importance, is the association of OSA with cardiovascular disorders [5]. OSA has been identified as a crucial intermediate factor in the pathophysiology of hypertension, ischemic heart disease, arrhythmias, stroke and diabetes. Treatment of sleep-disordered breathing is known to improve outcomes after congestive heart failure and stroke [7, 8]

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Results

Conclusion