title: Cortisol levels and metabolic parameters in middle- and advanced- age subjects: associations with age.
abstract: BACKGROUND
  It has been reported that morning cortisol levels increase with age, although there is some controversy in the literature.
  
  
  OBJECTIVE
  The aim of this study was to examine associations of cortisol levels with advancing age in an elderly population and investigate possible interactions with metabolic and hormonal parameters.
  
  
  METHODS
  From 372 subjects initially evaluated, we studied 251 ambulatory subjects aged 51-90 yr, median 71 yr (169 women), all permanent residents of a small town in southern Greece. Anthropometric parameters, glucose, insulin, cortisol, and biochemical parameters were recorded.
  
  
  RESULTS
  Fasting cortisol levels (08:00-09:00 h) varied between 150.9- 854 nmol/l (mean 362.4 nmol/l). A significant association was found between age and cortisol levels (Spearman's rho =0.170, p=0.01). There was a positive correlation between cortisol levels and creatinine (Spearman's rho =0.144, p=0.023), homocysteine (Spearman's rho =0.283, p<0.001) and a negative correlation with body mass index (Spearman's rho =-0.128, p=0.047). Multivariate analysis showed that when creatinine was taken into account, the association of cortisol with age and with homocysteine was no longer significant. When, however, diabetic subjects were included in the analysis, the adjusted for creatinine association of cortisol with age was significant (β=0.168, p<0.05).
  
  
  CONCLUSIONS
  It is concluded that, in elderly ambulatory subjects, the reported associations between cortisol levels, age, and homocysteine may be affected by coexisting co-morbidities or possibly by a decline in renal function. In subsequent studies it is important that fasting glycemia is taken into account.
authors.affiliation: Endocrinology, Metabolism and Diabetes Unit, Department of Medical Therapeutics, Alexandra Hospital, Athens University School of Medicine, 34 Evrytanias street, 18121 Athens, Greece. kterz@otenet.gr
authors.forename: K
authors.initials: K
authors.lastname: Terzidis
authors.forename: A
authors.initials: A
authors.lastname: Panoutsopoulos
authors.forename: A
authors.initials: A
authors.lastname: Mantzou
authors.forename: P
authors.initials: P
authors.lastname: Tourli
authors.forename: G
authors.initials: G
authors.lastname: Papageorgiou
authors.forename: K
authors.initials: K
authors.lastname: Saltiki
authors.forename: G
authors.initials: G
authors.lastname: Tsagalis
authors.forename: C
authors.initials: C
authors.lastname: Mara
authors.forename: M
authors.initials: M
authors.lastname: Alevizaki
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood* / Q000378:metabolism; D001786:Blood Glucose / Q000378:metabolism; D015992:Body Mass Index; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D006115:Greece / Q000453:epidemiology; D006710:Homocysteine / Q000097:blood; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D007328:Insulin / Q000097:blood; D008297:Male; D008875:Middle Aged; D049629:Waist-Hip Ratio / Q000379:methods
chemical_list: D001786:Blood Glucose; D007328:Insulin; D006710:Homocysteine; D006854:Hydrocortisone