Hair cortisol measurement in older adults: Influence of demographic and physiological factors and correlation with perceived stress.

AIMS: This study aimed to investigate correlation between hair cortisol levels and perceived stress scale (PSS) in addition to a range of demographic and physiological factors in a sample of older adults. EXPERIMENTAL: Hair cortisol concentrations were established from 42 older adults aged between 60 and 80 years old. Age, sex, hair colour, smoking status, employment status, daytime sleeping, medication, waist to hip ratio (WHR) and PSS scores were assessed through a questionnaire. Hair cortisol concentration was assessed through liquid chromatography coupled to tandem mass-spectrometry (LC-MS/MS). RESULTS: Amongst the older adult group there was no statistically significant correlation between hair cortisol concentration and age, employment status, daytime sleep duration, WHR or PSS. When compared to previous data assessing hair cortisol in toddlers (7 months to 3 years old), adolescents (12-17 years old) and adults (18-60 years old) it is observed that there is a trend for higher hair cortisol in older adults (60-80 years old). Hair cortisol concentrations were significantly higher in males (n = 20) than in females (n = 22) and in participants with dark brown hair (n = 8). No relationship was investigated between hair cortisol concentration and smoking status or medication intake. CONCLUSIONS: The results confirm that hair samples are a useful alternative to the current mediums that are used to analyse biological cortisol. The results also validate the use of LC-MS/MS as an effective analytical method for the quantitation of hair cortisol concentrations.