Convincing evidences has linked the hypothalamus-pituitary-adrenal (HPA) axis to aging patterns. F excess is implicated in the development of frailty characteristics whereas DHEAS is positively correlated to successful aging. We compared serum F and DHEAS levels of independent community-living (successful group, 19 M and 28 F, 69 to 87 yr) with those of institutionalized elderly (frail group, 20 M and 30 F, 65 to 95 yr). Serum F was determined at 1) baseline (08:00 h, 16:00 h and 23:00 h), 2) after 2 overnight dexamethasone (DEX) suppression tests (DST, using 0.25 and 1.0 mg doses), and 3) 60 min after ACTH stimulation (250 microg i.v. bolus); serum DHEAS was determined at 08:00 h. Basal serum F at 08:00 h, 16:00 h and 23:00 h and serum DHEAS levels were similar in both groups; however F: DHEAS ratio at 08:00 h was higher in the frail, compared to the successful group (mean +/- SD: 0.55 +/- 0.53 and 0.35 +/- 0.41, respectively; p = 0.04). In response to DST, F suppression was less effective in frail elderly after either 0.25 or 1.0 mg doses (9.0 +/- 6.0 and 2.0 +/- 0.9 microg/dl), as compared to the successful group (5.8 +/- 4.4 and 1.5 +/- 0.5 microg/dl) (p = 0.01). In addition, a significant correlation was observed between post-DEX F levels (both doses) and parameters of cognitive and physical frailty. Normal and similar F levels were observed after ACTH stimulation in both groups. Our data suggest a deficient feedback regulation of the HPA axis in frail institutionalized elderly, as demonstrated by a higher set point for F suppression. This augmented HPA tonus enforces the hypothesis that even milder F excess may be related to characteristics of frailty in the elderly.
Arq Bras Endocrinol Metab vol 45 nº 2 Abril 2001 157 RESUMOO envelhecimento é acompanhado de alterações orgânicas possivelmente relacionadas com o sistema endócrino. O eixo GH/IGF-1 e a produção de SDHEA declinam com a idade, caracterizando uma redução de suas atividades, que podem resultar em efeitos deletérios sobre a composição corporal, o sistema cardiovascular e a cognição. Avaliamos a concentração sérica basal de GH, IGF-1 e SDHEA em 225 idosos de uma comunidade (148 mulheres e 77 homens, 70 a 91 anos), 80% deles com características de envelhecimento bem sucedido (Minimental ≥24 e comprometimento de atividades de vida diária ≤3). Tanto o IMC como a pressão arterial estavam significativamente mais elevados nas mulheres. Os níveis de GH também eram maiores nas mulheres (1,6±1,7 vs. 1,0±1,3ng/ml, X±DP, p<0,001), estando acima da faixa de referência em 14% e 19% das mulheres e homens. Já os níveis de IGF-1 eram semelhantes (90±42 e 101±40ng/ml, NS), não sendo elevados em nenhum deles e reduzidos em 35% e 24%, respectivamente. Os níveis de SDHEA eram maiores nos homens (86±58 e 54±36µg/dl, p<0,001), porém na faixa de referência em 92% deles. Houve uma surpreendente correlação positiva entre idade e GH nos homens (r= 0,38, p<0,005), mas uma correlação negativa entre IGF-1 e idade nos dois grupos (r= -0,24 e r= -0,32). Nas mulheres, houve também uma correlação positiva entre SDHEA e IGF-1 (r= 0,27). Em conclusão, níveis basais de GH podem estar elevados em uma parcela significativa dos idosos, sendo maiores nas mulheres, enquanto os níveis de IGF-1 encontram-se normais ou baixos nos dois grupos, sugerindo quadro de resistência hormonal. Os níveis de SDHEA encontravam-se na faixa de referência, sendo maiores nos homens, caracterizando a perda da contribuição ovariana. Diferentemente do que se tem especulado, não encontramos correlação entre os níveis de SDHEA e qualquer parâmetro clínico investigado. ABSTRACTAging is associated with body changes, especially related with the endocrine system. The activity of the GH/IGF-1 axis and production of DHEAS decline significantly with aging, compromising body composition, cardiovascular and cognitive functions. We studied 225 elderly subjects from a community cohort (148 women and 77 men, 70 to 91 years) 80% of whom being considered "successful" (Mini-mental ≥24 and AVL ≤3). We measured basal serum levels of GH, IGF-1 and DHEAS and their possible correlations. Both, BMI and blood pressure levels were significantly higher in women. GH levels were also higher in women (1.6±1.7 vs. 1.0±1.3ng/ml, X±SD, p<0.001), and above the normal range in 14% and 19% of women and men. IGF-1 levels were similar (90±42 and 101±40ng/ml, NS), and were not elevated but low in 35% and 24%, respectively. On the other hand, DHEAS levels were higher in men (86±58 and 54±36µg/dl, p<0.001), but still within normal range in 92% of them. An
The aim of this study was to verify whether polysomnography represents a stressful situation by assessing cortisol levels and the sleep pattern of healthy community-living elderly admitted to a sleep disorder center (SDC). Subjects slept for two sequential nights at the SDC for polysomnographic recordings. Blood was sampled at 0800 h, 1600 h, and 2300 h and 24-h urine was collected for cortisol determination. Three months later, subjects were visited at home for blood and urinary collections. Cortisol levels were higher in the SDC than at home at 0800 h but were lower at 2300 h and similar at 1600 h. No differences were observed in urinary cortisol. Polysomnographic recordings indicated a poorer sleep pattern in the first night. Our data indicate that a short-term stay of healthy elderly in a SDC disrupts sleep pattern in the first of 2 nights, without representing a stressful experience, as evaluated by cortisol levels.
The increased cortisol secretion that occurs with aging is associated with characteristics of frailty. In this study we investigated whether healthy elderly women excrete increased amounts of urinary free cortisol (UFC) when compared to younger women. Twenty-four-hour UFC levels were measured in 25 elderly (70 to 87 years of age; median: 74) and 24 younger (19 to 59 years of age; median: 46) community-living women. All subjects were healthy and cognition was unimpaired. No differences in 24-hr UFC were observed between elderly and younger women (54.2 +/- 28.0 and 45.1 +/- 15.6 micrograms/24 hr, respectively) and no correlation was found between 24-hr UFC and age. Also, elderly and younger women had similar 24-hr urinary volumes (1366 +/- 531 and 1514 +/- 412 ml 24 hr, respectively) that did not correlate with UFC. In conclusion, older and younger healthy women have similar 24-hr UFC levels, possibly reflecting a comparable adrenocortical secretion of cortisol.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.