Age and sex differences of dehydroepiandrosterone sulfate (DHEAS) and cortisol (CRT) plasma levels in normal controls and Alzheimer's disease (AD)
In 50 healthy subjects (23 female, 27 male, aged 18–81) and 24 patients with Alzheimer's disease (AD) (11 female, 13 male, aged 58–88) DHEAS and CRT plasma levels were studied. In normal subjects there was a clear negative correlation of DHEAS to age, while no significant age correlated decrease of CRT plasma levels was found. There was a significant decrease in the DHEAS/CRT ratio in elderly controls (aged>60) as compared to young individuals (aged<45). Overall there was a trend to lower DHEAS/CRT ratios in AD patients compared to age matched controls out of the total group of normals (P<0.1), there was a significant decrease of this ratio in female AD patients (P<0.05), compared to age matched female controls, but there was none in male Alzheimers; furthermore there was a significant difference in CRT plasma levels between female AD patients and age matched female controls (P<0.01) and between female and male AD patients (P<0.05). Considering the antiglucocorticoid effects of DHEAS, this ratio may account for its protective effect against hippocampal degeneration caused by glucocorticoids and possibly for the higher rate of AD in females.