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Resumen:
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Excessive erythrocytosis (EE; Hct ? 63% in men) is the hallmark of Monge?s disease or Chronic Mountain Sickness (CMS), a debilitating syndrome with high prevalence in Andean highlanders. EE is associated with typical CMS neurological symptoms and increased cardiovascular risk. Although largely impractical, common treatment includes the relocation of individuals to lower altitudes, or periodic bloodletting and hemodilution. We have shown that, unlike sedentary residents at the same altitude, high-altitude (HA) athletes maintain Hct values within sea-level range. Thus, we hypothesize that aerobic training is associated with lower Hct levels and might reduce EE. Therefore, this study aimed to investigate the effect of 8-week sub-maximal aerobic exercise training on Hct and CMS symptoms. Eight HA native men (40.9 ± 4.0 y) from Cerro de Pasco-Peru (4340 m) with CMS (Hct: 70.6 ± 1.9 %, CMS score: 8.8 ± 1.4) participated in the study. Clinical examination included questionnaires, spirometry, and ECG. Physiological measurements at baseline included Hct, arterial O2 saturation as measured by pulse oximetry (SpO2), heart rate (HR), blood pressure (BP), and a maximal exercise test to determine ventilatory parameters and peak VO2. 24h BP was measured by ambulatory BP monitoring (ABPM). Blood samples were collected for full blood cardiometabolic (CM) profiling and haptoglobin determination as a hemolysis marker. CMS score was assessed to determine the severity of the syndrome. All measurements were repeated after 4 and 8 weeks of exercise training. Sub-maximal aerobic work consisted of pedaling-exercise in a cycle-ergometer at 60% of peak VO2 for 1h/day, 4 days/week for 8 weeks. After 4 weeks, a maximal exercise test was repeated to readjust 60% of peak VO2 for the following 4 weeks. Hct decreased significantly by 5% and 7% (p
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