Associations between the cortisol awakening response and patient-evaluated stress and mood instability in patients with bipolar disorder: an exploratory study

International Journal of Bipolar Disorders

Table 3 Associations between cortisol awakening response (CAR) and patient-evaluated perceived stress and mood instability measured daily using smartphones, questionnaire-based perceived stress, clinically evaluated functioning, depressive symptoms and manic symptoms, respectively in patients with bipolar disorder

	Model^a
	B	95% CI	p
Analyses including all patients, n = 67
CAR
PSS ^c	− 1.63	− 10.53; 7.26	0.72
FAST	− 1.18	− 6.48; 4.12	0.66
HDRS	− 6.79	− 17.89; 4.30	0.23
YMRS	− 12.88	− 29.92; 4.15	0.14
Analyses including only patients using a smartphone-based monitoring system, n = 33
CAR
Stress measured using smartphones^b	134.14	1.35; 266.92	0.048
Mood Instability measured using smartphones^c	430.23	52.41; 808.04	0.026
PSS	10.73	− 2.78; 24.23	0.12
FAST	3.72	− 5.64; 13.09	0.44
HDRS	4.97	− 12.36; 22.31	0.58
YMRS	− 3.93	− 27.46; 19.61	0.74
Effect of smartphone-based treatment. Control group serve as reference, n = 67
CAR	− 16.57	− 183.11; 216.25	0.87

^aModel: Adjusted for age and gender
CAR Cortisol Awakening Response; PSS: Perceived stress measured using Cohen’s Perceived Stress Scale; FAST Psychosocial functioning measured using Functional Assessment Short Test; HDRS Hamilton Depression Rating Scale; YMRS Young Mania Rating Scale; ^bStress measured using smartphone was evaluated on a scale from 0 to 5; ^cMood Instability calculated as the number of mood changes from day to day from baseline to three months and from three months to 6 months