Breathing Patterns and Oxygenation Saturation During Sleep in Children Habitually Living at High Altitude in the Andes: A Systematic Review

Abstract

BackgroundHuman respiratory physiology changes significantly in high altitude settings and these changes are particularly marked during sleep. It is estimated that 170 million people live above 2,500 m in environments where normal sleep parameters differ from those established at sea level or low altitude.MethodsWe conducted a systematic review of publications reporting sleep studies in healthy children living at high altitude. For this purpose, data from PubMed, EMBASE, SciELO and Epistemomikos bases were retrieved up to August 2021.ResultsSix articles met specified inclusion criteria; all reporting data were from South America involving 245 children (404 sleep studies) in children aged 0.6 months to 18 years, at altitudes between 2,560 to 3,775 m. The main results were: (1) Central apnea index decreased as the age increased. (2) The obstructive apnea/hypopnea index showed a bimodal profile with an increase in young infants up to age of 4 months, decreasing to 15 months of age, and then a second peak in children aged 4 to 9 years of age, dropping in older schoolchildren and adolescents. (3) Periodic breathing in the first months of life is more marked with increasing altitude and decreases with age.ConclusionsThere are few studies of sleep physiology in children living at high altitude. The international parameters defining normal apnea indices currently used at low altitude cannot be applied to high altitude settings. The interpretation of sleep studies in children living at high altitude is complex because there are important developmental changes across childhood and a wide range of altitude locations. More normative data are required to determine thresholds for respiratory pathology at a variety of high altitude settings.

Prevalence of pulmonary hypertension in children with obstructive sleep apnea living at high altitude

“…A previous study of ours and the study by Hill et al show an improvement of these parameters with age, from infancy to childhood, suggesting a developmental adaptation of respiratory sleep physiology at high altitude [ 35 , 36 ]. The systematic review by Ucros et al on the respiratory pattern during sleep at high altitude included mostly infants and only two studies in schoolchildren, one of which has a small number of patients and was performed with polygraphy, and the other by Hill et al in schoolchildren and adolescents, in which they reported IAHO values of 2(3.5) and IAO: 0(0) [ 37 ]. Recently, our group established normal values for children aged 5–17 years and found a median IAHO of 1.4(0.9–2.1) in children older than 10 years and 0–9(0.5–1.3) in children younger than 10 years [ 38 ].…”

“…Two other limitations of our study are the use of normal values of PSG at sea level in the absence of standardized values at high altitude for the reasons mentioned above, and the fact that our population included children between 2 and 16 years of age. This is important considering that in the meta-analysis by Uros et al 6 of the included studies were performed in infants [ 37 ], which were not part of our population; the study by Uros et al included only children up to 9 years of age and used polygraphy instead of PSG(19), and the study by Hill et al included children from 9 years of age [ 57 ]; therefore, extrapolation of the data from these two studies to our population was not considered appropriate from a methodological point of view. In addition, the use of PASP values reported at sea level is also a limitation; however, as noted above, there is no consensus on this issue, and the study by Pang et al, although using echocardiography, did not report PASP(13), which is based on the TRV, the variable recommended for adults and children at as a screening tool to identify patients with possible pulmonary hypertension [ 22 , 58 ].…”

The Brain at High Altitude: From Molecular Signaling to Cognitive Performance

“…The statistical distribution of SpO 2 in children at HA shows that one out of four children saturates significantly less than the others [ 31 ]. Moreover, in one out of four children at HA, the oxygen desaturation index during sleep (which reflects SpO 2 variability) is lower [ 32 , 33 ]. Changes in sleep patterns can modulate mood and cause deficits in working memory, attention, or executive functions [ 34 ].…”

Neumología De Altura: Saturación De Oxígeno, Edema Pulmonar Y Pruebas De Función Pulmonar

“…De lo mencionado en este corto espacio, puede deducirse que los cambios de los valores de la SatO2 en alturas >2.500 m, deben tenerse en cuenta para el diagnóstico y tratamiento de condiciones clínicas tan relevantes como la infección respiratoria aguda, la displasia bron-copulmonar (7) y los trastornos respiratorios asociados al sueño (6). Para ampliar estos conceptos invitamos al lector a consultar la bibliografía seleccionada.…”