Aging, Tolerance to High Altitude, and Cardiorespiratory Response to Hypoxia

Abstract

Richalet, Jean-Paul, and François J. Lhuissier. Aging, tolerance to high altitude, and cardiorespiratory response to hypoxia. High Alt Med Biol. 16:117-124, 2015.--It is generally accepted that aging is rather protective, at least at moderate altitude. Some anecdotal reports even mention successful ascent of peaks over 8000 m and even Everest by elderly people. However, very few studies have explored the influence of aging on tolerance to high altitude and prevalence of acute high altitude related diseases, taking into account all confounding factors such as speed of ascent, altitude reached, sex, training status, and chemo-responsiveness. Changes in physiological responses to hypoxia with aging were assessed through a cross-sectional 20-year study including 4675 subjects (2789 men, 1886 women; 14-85 yrs old) and a longitudinal study including 30 subjects explored at a mean 10.4-year interval. In men, ventilatory response to hypoxia increased, while desaturation was less pronounced with aging. Cardiac response to hypoxia was blunted with aging in both genders. Similar results were found in the longitudinal study, with a decrease in cardiac and an increase in ventilatory response to hypoxia with aging. These adaptive responses were less pronounced or absent in post-menopausal untrained women. In conclusion, in normal healthy and active subjects, aging has no deleterious effect on cardiac and ventilatory responses to hypoxia, at least up to the eighth decade. Aging is not a contraindication for high altitude, as far as no pathological condition interferes and physical fitness is compatible with the intensity of the expected physical demand of one's individual. Physiological evaluation through hypoxic exercise testing before going to high altitude is helpful to detect risk factors of severe high altitude-related diseases.

Exaggerated pulmonary vascular response to acute hypoxia in older men

“…). There is also evidence to suggest that the manner in which ventilatory responses to acute hypoxia change with age is influenced by sex (Richalet & Lhuissier, ). It would clearly be of interest for future studies to examine different phases of the time course of HPV, sex differences, several different age groups and even different postures (Kovacs et al .…”

“…); another concluded that ‘some animal studies show diminution of HPV with ageing, but this has not been demonstrated in humans’ (Lumb & Slinger, ). In contrast to the effect of ageing on the acute hypoxic ventilatory response, which has been examined by several studies, albeit with inconsistent results (Richalet & Lhuissier, ), the impact of ageing on HPV in adult humans is unknown (Swenson, ).…”

Twelve weeks of exercise modality in hypoxia enhances health‐related function in obese older Korean men: A randomized controlled trial

“…In general, exercise intervention in hypoxia enhances respiratory muscle function through hypoxia‐induced chemoreceptor stimulation and hyperventilation . Adaptation to hypoxia inhibited the activity of the sympathetic nervous system by a decreased excretion rate of norepinephrine and an increase of vagal nerve activity .…”

“…However, the majority of studies on obesity and aging have mainly been carried out in Western society, and studies using hypoxic therapy for health promotion of the older adult population are very limited. 3,[14][15][16][17][18] Until now, the majority of obese and aging studies have focused on abdominal or central obesity, hypertension, insulin resistance, high triglyceride and low high-density lipoprotein cholesterol levels, which are associated with metabolic syndrome. 6 The numerous changes in health-related factors that occur during the process of obesity and aging need to be investigated.…”

“…1 In general, exercise intervention in hypoxia enhances respiratory muscle function through hypoxia-induced chemoreceptor stimulation and hyperventilation. 11,18 Adaptation to hypoxia inhibited the activity of the sympathetic nervous system by a decreased excretion rate of norepinephrine and an increase of vagal nerve activity. 5,10 These physiological changes indicate that exercise intervention in hypoxia can enhance pulmonary function and HRV, which are important health-related functions in obese older people.…”