Hair Cortisol Concentration and its Association with Perceived Stress in Men and Women: An Investigative Study

Abstract

Introduction - The measurement of cortisol in hair has emerged in recent years as a reliable way of quantifying long term cortisol production. Some controversies remain, however, among these is the possibility of a gender disparity and the connection between perceived stress and cortisol release. Aims - To measure the cortisol present within the hair of a small group of healthy volunteers and compare this against their perceived stress, assessed using the 10-point Perceived Stress Scale, alongside various lifestyle and health factors. Methods - 20 volunteers (15 female) were recruited to the study. BMI, blood pressure and hair colour were measured. Hair of at least 6 cm in length was sampled from the posterior vertex region of the scalp then volunteers answered the Perceived Stress Scale and a variety of questions regarding their health (including any chronic conditions and oral contraceptive use) and lifestyle habits (such as smoking status, alcohol consumption and hair dye use). Cortisol was measured using an in-house salivary ELISA. Results - The average hair cortisol concentration (HCC) in the study group was 155.7 pg/mg (SD 101.13 pg/mg). In the female cohort the mean HCC was 152.76 pg/mg (SD 111.76 pg/mg) while in the male cohort the average HCC was 164.79 pg/mg (SD 68.78 pg/mg), there was no significant influence of gender upon HCC (P = .83). No significant associations were found between HCC and the studied lifestyle factors (all P's = >0.05) however one participant who was found to have type I diabetes did have significantly raised HCC (participant HCC 390.5 pg/mg vs mean study HCC of 155.7 pg/mg, P = .013). No other health factors portrayed any significant affect upon HCC (all P's = >0.05). Keywords: Hair Cortisol; Perceived Stress; Gender; Steroids; ELISA