. Author manuscript; available in PMC: 2013 Oct 1.

Published in final edited form as: Brain Behav Immun. 2012 Jun 9;26(7):1047–1056. doi: 10.1016/j.bbi.2012.06.002

Table 3.

Loss of Regulatory Association between Sleep Quality and Nocturnal Cortisol Secretion Among Patients but not Controls.

Outcome = λ_I Nocturnal Non-ACTH Influences	Standardized β	t-Test (df = 32)	p-Value
Healthy Controls (n = 36)
Age	.304	2.068	0.047^*
Gender	.124	0.843	0.405
Poor sleep quality (PSQI)	−.547	−3.105	0.001^**
Patients (n = 36)
Age	.378	2.201	0.035^*
Gender	.072	0.417	0.679
Poor sleep quality (PSQI)	.004	0.022	0.983

The Pittsburgh Sleep Quality Index (PSQI) global score (higher = worse) reflects sleep disturbance over the previous month. Separate multiple regression analyses were conducted in controls and patients examining the association between PSQI and nocturnal Non-ACTH influences (λ_I) on cortisol, controlling for demographics.

^**

p < .01.

p < .05.