. 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 2.

The nocturnal dynamic system parameters and steady state gain are associated with somatic symptoms in patients with functional disorders.

Outcome = somatic symptoms	Standardized β	t-Test (df = 32)	p-Value
Unadjusted model
ACTH-adrenal signaling (λ_A)	−0.553	−3.105	0.004^**
Inhibitory feedback (λ_C)	0.425	2.309	0.028^*
External influences (λ_I)	−0.284	−1.789	0.083^†
Adjusted final model		(df = 31)
Age	−0.136	−0.808	0.425
Gender	0.013	0.076	0.940
Depressive symptoms	−0.158	−0.970	0.339
Steady state gain (λ_A/λ_C)	−0.401	−2.416	0.022^*

The nocturnal parameters were calculated between 11 pm and 9 am. Higher levels of somatic symptoms were associated with: ↓λ_A = less cortisol per unit ACTH, ↑λ_C = greater inhibition/more efficient removal of cortisol from circulation, ↓λ_I = lower cortisol per unit of the external influences, and ↓λ_A/λ_C= steady state gain decreases indicate that overall there is a lower level of cortisol activation for a given amount of ACTH secretion.

^**

p < .01.

p < .05.

^†

p ≤ .10.