SLEEP 2011 Abstract Supplement

B. Clinical Sleep Science VIII. Medical Disorders and Sleep
we investigated the incidence of CHD in the Wisconsin Sleep Cohort
Study (WSCS).
Methods: The population-based WSCS sample consisted of 1198 adults,
free of CHD at baseline and not treated for SDB, followed longitudinally
over 20 years. SDB was defined by the apnea-hypopnea index (AHI)
using overnight polysomnography. We used baseline log (AHI+1) as the
predictor variable in survival analysis models predicting incident CHD.
Incident CHD was defined by new reports of myocardial infarction, cardiac
revascularization procedure, congestive heart failure or coronary
heart disease death obtained using detailed health history questionnaire
repeated at 4-year intervals and mortality data.
Results: Participants’ mean age was 47 (range: 30-70) years; 54% were
men. The incidence of CHD in the WSCS was 7.14/1000 person-years.
The mean time to event was 9.2 ± 4.9 years. Using AHI as categorical
data, the unadjusted incidence of CHD per 1000 person-years was,
4.57 and 10.47 in AHI 15-30 and AHI ≥30 respectively, compared with
6.21 in those with AHI