Association of Diurnal Patterns in Salivary Cortisol With Type 2 Diabetes in the Whitehall II Study

• Published in: The journal of clinical endocrinology and metabolism Vol. 99; no. 12; pp. 4625 - 4631
• Main Authors: Hackett, Ruth A, Steptoe, Andrew, Kumari, Meena
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Endocrine Society 01.12.2014; Copyright by The Endocrine Society
• Subjects: Aged; Arousal; Biological and medical sciences; Circadian Rhythm; Cohort Studies; Cross-Sectional Studies; Diabetes Mellitus, Type 2 - metabolism; Diabetes. Impaired glucose tolerance; Endocrine pancreas. Apud cells (diseases); Endocrine Research; Endocrinopathies; Etiopathogenesis. Screening. Investigations. Target tissue resistance; Feeding. Feeding behavior; Female; Fundamental and applied biological sciences. Psychology; Humans; Hydrocortisone - metabolism; Male; Medical sciences; Middle Aged; Saliva - metabolism; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Vertebrates: endocrinology; Endocrinopathy; Type 2 diabetes; Corticosteroid; Obesity; Nutrition; Steroid hormone; Nutrition disorder; Antiinflammatory agent; Metabolic diseases; Cortisol; Hydrocortisone; Glucocorticoid; Epidemiology; Prospective; Association; Cohort study; Adrenal hormone; Saliva; Endocrinology; Nutritional status; Public health
• ISSN: 0021-972X; 1945-7197
• DOI: 10.1210/jc.2014-2459

Context: The hypothalamic pituitary-adrenal axis is thought to play a role in Type 2 Diabetes (T2D). However, the evidence for an association between diurnal cortisol patterns and T2D is equivocal. Objective: The aim was to examine the association of cortisol patterns throughout the day with T2D status in a community-dwelling population. Design: This was a cross-sectional study of T2D status and salivary cortisol from phase 7 (2002–2004) of the Whitehall II study, United Kingdom. Setting: The occupational cohort was originally recruited in 1985–1988. Participants: Three-thousand, five-hundred eight white men and women including 238 participants with T2D aged 50–74 years with complete information on cortisol secretion participated. Outcome Measures: We measured diurnal cortisol (nmol/L) patterns from six saliva samples obtained over the course of a normal day: at waking, +30 min, +2.5, +8, +12 hours, and bedtime. The cortisol awakening response and slope in diurnal secretion were calculated. Results: T2D status was associated with a flatter slope in cortisol decline across the day (b = 0.004; confidence interval [CI], 0.001–0.007; P = .014) and greater bedtime cortisol (b = 0.063; CI, 0.010–0.117; P = 0.020) independent of a wide range of covariates measured at the time of cortisol assessment. There was no association between morning cortisol, the cortisol awakening response, and T2D (P > .05). Conclusions: In this nonclinical population, T2D was associated with a flatter slope in cortisol levels across the day and raised bedtime cortisol values.