Table 4.

Mean slope^a of the regression line fitted to the awakening cortisol pattern by tertiles of the total stress index for the top five most stressful and bottom five least stressful events.

Stressor category	Tertiles of stress indexb (range)	N	Unadjusted (mean ± SD)	Age-adjusted (mean ± SE)	Multivariable adjustedc (mean ± SE)
Top five most stressful	Low (0–0)	115	0.0174 ± 0.034	0.0171 ± 0.003	0.0173 ± 0.003
	Medium (5–140)	110	0.0067 ± 0.031	0.0069 ± 0.003	0.0072 ± 0.003
	High (142–1360)	113	0.0060 ± 0.025	0.0062 ± 0.003	0.0068 ± 0.003
	P-value (ANOVA)*		0.0070	0.0163	0.0188
	P-value (trend)**		0.0244	0.0386	0.0430
Bottom five least stressful	Low (0–0)	114	0.0081 ± 0.031	0.0076 ± 0.003	0.0089 ± 0.003
	Medium (5–155)	111	0.0120 ± 0.031	0.0124 ± 0.003	0.0132 ± 0.003
	High (160–1600)	113	0.0103 ± 0.030	0.0105 ± 0.003	0.0092 ± 0.003
	P-value (ANOVA)*		0.6403	0.5118	0.5171
	P-value (trend)**		0.8610	0.8299	0.7595

^*P-value from analysis of variance or covariance comparing any differences in mean slope across stress index tertiles. Pairwise multiple comparison shows significant differences in mean slope between those in the lowest tertile and those in medium or high stress index categories for the top five most stressful events.

^**P-value from linear regression testing linear trend in mean slope across increasing stress index.

^aSlope was estimated by fitting a simple linear regression model where cortisol in log scale was regressed on time (in minutes) since baseline sample.

^bThe sum of stress index (product of rating and frequency of occurrence in the past month) for the top five most stressful or bottom five least stressful events.

^cAdjusted for age, gender, marital status, alcohol consumption, and rank.