TY - JOUR

T1 - Global REACH 2018: Volume regulation in high-altitude Andeans with and without chronic mountain sickness

AU - Steele, Andrew

AU - Tymko, Michael

AU - Meah, Victoria L.

AU - Simpson, Lydia

AU - Gasho, Chris

AU - Dawkins, Tony

AU - Williams, Alexandra

AU - Villafuerte, Francisco

AU - Vizcardo-Galindo, Gustavo

AU - Figueroa-Mujíca , Rómulo Joseph

AU - Ainslie, Philip

AU - Stembridge, Mike

AU - Moore, Jonathan

AU - Steinback, Craig

PY - 2021/9/1

Y1 - 2021/9/1

N2 - The high-altitude maladaptation syndrome known as chronic mountain sickness (CMS) is characterized by polycythemia and is associated with proteinuria despite unaltered glomerular filtration rate. However, it remains unclear if indigenous highlanders with CMS have altered volume regulatory hormones. We assessed NH2-terminal pro-B-type natriuretic peptide (NT pro-BNP), plasma aldosterone concentration, plasma renin activity, kidney function (urinary microalbumin, glomerular filtration rate), blood volume, and estimated pulmonary artery systolic pressure (ePASP) in Andean males without ( n = 14; age = 39 ± 11 yr) and with ( n = 10; age = 40 ± 12 yr) CMS at 4,330 m (Cerro de Pasco, Peru). Plasma renin activity (non-CMS: 15.8 ± 7.9 ng/mL vs. CMS: 8.7 ± 5.4 ng/mL; P = 0.025) and plasma aldosterone concentration (non-CMS: 77.5 ± 35.5 pg/mL vs. CMS: 54.2 ± 28.9 pg/mL; P = 0.018) were lower in highlanders with CMS compared with non-CMS, whereas NT pro-BNP was not different between groups (non-CMS: 1394.9 ± 214.3 pg/mL vs. CMS: 1451.1 ± 327.8 pg/mL; P = 0.15). Highlanders had similar total blood volume (non-CMS: 90 ± 15 mL·kg−1 vs. CMS: 103 ± 18 mL·kg−1; P = 0.071), but Andeans with CMS had greater total red blood cell volume (non-CMS: 46 ± 10 mL·kg−1 vs. CMS: 66 ± 14 mL·kg−1; P < 0.01) and smaller plasma volume (non-CMS: 43 ± 7 mL·kg−1 vs. CMS: 35 ± 5 mL·kg−1; P = 0.03) compared with non-CMS. There were no differences in ePASP between groups (non-CMS: 32 ± 9 mmHg vs. CMS: 31 ± 8 mmHg; P = 0.6). A negative correlation was found between plasma renin activity and glomerular filtration rate in both groups (group: r = −0.66; P < 0.01; non-CMS: r = −0.60; P = 0.022; CMS: r = −0.63; P = 0.049). A smaller plasma volume in Andeans with CMS may indicate an additional CMS maladaptation to high altitude, causing potentially greater polycythemia and clinical symptoms.

AB - The high-altitude maladaptation syndrome known as chronic mountain sickness (CMS) is characterized by polycythemia and is associated with proteinuria despite unaltered glomerular filtration rate. However, it remains unclear if indigenous highlanders with CMS have altered volume regulatory hormones. We assessed NH2-terminal pro-B-type natriuretic peptide (NT pro-BNP), plasma aldosterone concentration, plasma renin activity, kidney function (urinary microalbumin, glomerular filtration rate), blood volume, and estimated pulmonary artery systolic pressure (ePASP) in Andean males without ( n = 14; age = 39 ± 11 yr) and with ( n = 10; age = 40 ± 12 yr) CMS at 4,330 m (Cerro de Pasco, Peru). Plasma renin activity (non-CMS: 15.8 ± 7.9 ng/mL vs. CMS: 8.7 ± 5.4 ng/mL; P = 0.025) and plasma aldosterone concentration (non-CMS: 77.5 ± 35.5 pg/mL vs. CMS: 54.2 ± 28.9 pg/mL; P = 0.018) were lower in highlanders with CMS compared with non-CMS, whereas NT pro-BNP was not different between groups (non-CMS: 1394.9 ± 214.3 pg/mL vs. CMS: 1451.1 ± 327.8 pg/mL; P = 0.15). Highlanders had similar total blood volume (non-CMS: 90 ± 15 mL·kg−1 vs. CMS: 103 ± 18 mL·kg−1; P = 0.071), but Andeans with CMS had greater total red blood cell volume (non-CMS: 46 ± 10 mL·kg−1 vs. CMS: 66 ± 14 mL·kg−1; P < 0.01) and smaller plasma volume (non-CMS: 43 ± 7 mL·kg−1 vs. CMS: 35 ± 5 mL·kg−1; P = 0.03) compared with non-CMS. There were no differences in ePASP between groups (non-CMS: 32 ± 9 mmHg vs. CMS: 31 ± 8 mmHg; P = 0.6). A negative correlation was found between plasma renin activity and glomerular filtration rate in both groups (group: r = −0.66; P < 0.01; non-CMS: r = −0.60; P = 0.022; CMS: r = −0.63; P = 0.049). A smaller plasma volume in Andeans with CMS may indicate an additional CMS maladaptation to high altitude, causing potentially greater polycythemia and clinical symptoms.

KW - Blood volume

KW - High-altitude

KW - Renal function

KW - Volume regulation

U2 - 10.1152/ajpregu.00102.2021

DO - 10.1152/ajpregu.00102.2021

M3 - Article

VL - 321

SP - R504-R512

JO - American Journal of Physiology - Regulatory Integrative and Comparative Physiology

JF - American Journal of Physiology - Regulatory Integrative and Comparative Physiology

SN - 0363-6119

IS - 3

ER -