Table 3.

Variation of adjusted associations between cardiovascular risk factors by age for AHI

	Age <65 Yr (n = 523)		Age ≥65 Yr (n = 813)		P for Interaction
	β-Value	95% CI	β-Value	95% CI lower, upper
WBC total count, ×103/μl	0.078	0.024, 0.133	0.007	−0.015, 0.029	0.006
Neutrophils, ×103/μl	0.089	0.018, 0.160	0.040	−3.220 × 10−4, 0.080	0.098
HDL cholesterol, mg/dl	−0.004	−0.010, 0.002	−0.004	−0.009, 4.645 × 10−6	0.088
Fasting glucose, mg/dl*	0.003	0.001, 0.008	−0.001	−0.006, 0.003	0.006

Definition of abbreviations: AHI = apnea–hypopnea index [number of events per h of sleep; outcome variable was ln(AHI + 1)]; BMI = body mass index; CI = confidence interval; HDL = high-density lipoprotein; WBC = white blood cell.

Models shown when there was evidence of a suggestive (P < 0.10) or significant (P < 0.05) interaction with the risk factor and age category (<65 yr vs. ≥65 yr). Each row represents a unique regression model adjusted for sex, race/ethnicity, smoking, statin use, any antihypertensive medication, antidiabetes medication (insulin and/or hypoglycemic), BMI, and waist circumference for each stratified analysis. The P value for interaction terms are based on the full model, including an interaction term for age (<65 yr vs. ≥65 yr) and the exposures. P values in bold typeface highlight the statistical significance. Analyses based on n = 1,336 (without missing data). Values are natural logarithm transformations.

^*n = 1,104, restricted to those not using diabetes medication.