Obesity and metabolic syndrome: A phenotype of mild long-term hypercortisolism?

In clinical practice, a considerable overlap can be observed between the sequelae of obesity and an excess of glucocorticoids (i.e., Cushing’s syndrome). In Cushing’s, all aspects of the metabolic syndrome are frequently seen: abdominal obesity, insulin resistance, dyslipidemia, and hypertension. Furthermore, common variants in the glucocorticoid receptor which affect sensitivity to cortisol also affect adiposity and related metabolic characteristics. Overall, published research investigating the associations between adiposity and cortisol in blood, saliva, and urine have not provided consistent evidence that cortisol levels are associated with obesity in the general population. This lack of consistent associations may be because cortisol levels are highly variable due to acute stress, the diurnal rhythm, and day-to-day variations. This variability is refl ected in cortisol levels measured in human fl uid matrices. Over the past decade, the analysis of cortisol in scalp hair has emerged as a way to estimate cumulative cortisol exposure over prolonged periods of time. Hair cortisol levels have been found to be increased in obese individuals and are positively associated with body mass index and abdominal fat mass. Furthermore, increased hair cortisol has been associated with metabolic syndrome and cardiovascular disease in population-based studies. Although it is theoretically likely that a subtle chronic hypercortisolism contributes to the genesis of obesity and related cardiometabolic disturbances, causality has not been established yet. Future studies investigating hair cortisol levels, in particular those involving longitudinal designs and interventions, may greatly expand knowledge about the relationship between cortisol exposure and cardiometabolic health in the general population.

• View at Publisher
• View at Scopus