Steep disturbances are correlated with decreased morning awakening salivary cortisol

Morning and evening salivary cortisol levels were correlated with steep parameters in 14 patients with primary insomnia and 15 healthy controls. Salivary cortisol was sampled immediately after awakening (T1), 15 min later (T2), and immediately before going to bed (T3) for 1 week at home. In parallel with this, subjects estimated parameters of steep in a daily steep log. Patients and controls were all non-smokers who did not differ regarding morning awakening time or bedtime. Cortisol after awakening was significantly decreased in primary insomnia. Salivary cortisol at the time of awakening correlated negatively with the subjective estimation of steep quality, i.e. a low salivary cortisol level directly after awakening correlated with a higher frequency of nightly awakenings (r = -0.50), a diminished steep quality (r = -0.34) and a decreased feeling of recovery after awakening (r = -0.35; all p < 0.05). Furthermore, awakening cortisol was negatively correlated with the Pittsburgh Steep Quality Index (r = -0.43) and with a questionnaire on steep-related cognitions with the subscales rumination in bed (r = -0.56) and focusing on steep-related thoughts (r = -0.46; all p < 0.05). (C) 2004 Elsevier Ltd. All rights reserved.