Adrenopause or decline of serum adrenal androgens with age in women living at sea level or at high altitude

Abstract

The present study aimed to determine adrenopause or reduction of serum adrenal androgens with age at high altitude and at sea level. It was a cross-sectional study performed in 210 women resident at high altitude (4340 m) and 123 women living in Lima (150 m), aged 20-70 years. Fasting early morning blood samples were obtained. Serum dehydroepiandrosterone (DHEA), DHEA sulphate (DHEAS), androstenedione, testosterone and estradiol were measured by radioimmunoassay. Serum testosterone concentrations were greater in women living at high altitude than in those resident at sea level. Serum concentrations of DHEA, DHEAS and androstenedione were lower in women living at high altitude than in those living at sea level. The DHEAS/DHEA ratio was significantly greater, and the androstenedione/testosterone ratio was lower in samples from women living at high altitude. Among women older than 50 years of age, a greater decline in serum concentrations of DHEA was observed in those living at high altitude than in those living at sea level. Among women 60-70 years of age, serum concentrations of DHEA at high altitude were 46·9% of those in women of the same age living at sea level. Decay of DHEAS at sea level and at high altitude occurred from the age of 40 years. The decline was faster at high altitude than at sea level, and in women aged 60-70 years serum values of DHEAS at high altitude were 56% of those at sea level. In the same age group, serum concentrations of androstenedione among those native to high altitudes were 27·34% of the value at sea level. At sea level, serum testosterone concentrations did not change with age from 20 to 70 years. In women aged 20-39 years and 50-59 years, serum testosterone concentrations were greater at high altitude than at sea level (P<0·05). In those aged 60-70 years, the concentrations were similar in those living at sea level and at high altitude. At sea level and at high altitude, the serum testosterone/estradiol ratio increased with age (P<0·0034 and P<0·0001 respectively). This ratio increased at an earlier age among those living at high altitude (40-49 years) than among those living at sea level (50-59 years). Multivariate analysis showed that altitude (P<0·0001) and greater chronological age (P<0·001) were associated with lower serum DHEAS concentrations. DHEAS was related to chronological age (P<0·0001). Low serum androstenedione concentrations were related to living at high altitude at birth and greater chronological age (P<0·0001). In conclusion, adrenopause is attained earlier and is of greater magnitude at high altitude than at sea level.

Serum testosterone levels and excessive erythrocytosis during the process of adaptation to high altitudes

“…At sea level and at HA, the serum testosterone/oestradiol ratio increases with age (P,0.0034 and P,0.0001, respectively). 109 These data suggest that in women as well as in men 106 living at HA, there is a greater conversion of DHEAS to testosterone, indicating a higher activity of 17beta-HSDs. We demonstrated in Cerro de Pasco (altitude 4340 m) that serum testosterone/oestradiol values become higher as haematocrit/Hb increases, 110 suggesting that the effects of higher testosterone or testosterone/oestradiol levels impact both men and women at HA.…”

“…This seems to be related to the increased conversion of DHEAS into testosterone. 106,109 Further analyses of men at HA with erythrocytosis show higher serum androstenedione levels and a lower testosterone/androstenedione ratio than men with EE, suggesting reduced 17beta-HSD activity. 106 Lower 17beta-HSD activity through D4-steroid production 112 in men with erythrocytosis at HA may protect against elevated serum testosterone levels and prevent EE.…”

The Proximate Determinants of Fertility in Populations Exposed to Chronic Hypoxia

“…Particularly relevant for our analysis are comparisons of the residents of Cerro de Pasco at 4350 m with women in Lima at 150 m (Escudero et al, 1996;Gonzales and Villena, 1997;Gonzales and Goñez, 2000;Gonzales et al, 2002).…”

Role of Maca (Lepidium meyenii) Consumption on Serum Interleukin-6 Levels and Health Status in Populations Living in the Peruvian Central Andes over 4000 m of Altitude

“…This may account for a suggested earlier aging in highland populations compared to lowlanders [15]. In addition, excessive erythrocytosis is associated with a pathological condition named “chronic mountain sickness” (CMS) [16].…”