Sleep disordered breathing and metabolic syndrome.
BACKGROUND
Sleep disordered breathing (SDB) has been associated with cardiovascular disease, hypertension, and insulin resistance. This article examines the association between SDB and the prevalence of metabolic syndrome (MS) in a community-based sample.


METHODS
A subset of participants in the Wisconsin Sleep Cohort Study (N=546) participated in an ancillary study to measure vascular and metabolic function. SDB was characterized using the apnea-hypopnea index (AHI) obtained in the polysomnography study closest to the collection of the metabolic measures. MS was defined using the National Cholesterol Education Program definition, and the homeostasis model assessment method (HOMA) was used to characterize insulin resistance.


RESULTS
SDB was significantly correlated with insulin resistance (Spearman r correlation between AHI and HOMA=0.30, P<0.0001). Compared with those without SDB (AHI <5), the age-sex-adjusted odds ratios of MS associated with mild (AHA 5-14.9) and moderate/severe SDB (AHI > or = 15 or CPAP) were 4.0 (95% CI 2.6, 6.3) and 5.3 (95% CI 3.2, 8.8), respectively. Additional adjustment for markers of sympathetic or neuroendocrine activation (urinary norepinephrine, cortisol, heart rate variability) did not materially alter these estimates. These associations were weaker but remained statistically significant after adjusting for body mass index.


CONCLUSIONS
SDB might be considered an integral component of MS.
Nieto
F Javier
FJ
Department of Population Health Sciences, University of Wisconsin School of Medicine and Public Health, 707C WARF Office Building, 610 Walnut St, Madison, WI 53726, USA. fjnieto@wisc.edu
Peppard
Paul E
PE
Young
Terry B
TB
D000328:Adult; D000368:Aged; D016009:Chi-Square Distribution; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007333:Insulin Resistance; D016015:Logistic Models; D008297:Male; D024821:Metabolic Syndrome / Q000453:epidemiology*; D008875:Middle Aged; D017286:Polysomnography; D012307:Risk Factors; D012891:Sleep Apnea Syndromes / Q000453:epidemiology*; D014922:Wisconsin / Q000453:epidemiology