The effect of high- to low-altitude adaptation on the multifocal electroretinogram

Peter Kristian Kofoed; Birgit Sander; Gustavo Zubieta-Calleja; Line Kessel; Kristian Klemp; Michael Larsen; Peter Kristian Kofoed; Birgit Sander; Gustavo Zubieta-Calleja; Line Kessel; Kristian Klemp; Michael Larsen

doi:10.1167/iovs.08-3216

The effect of high- to low-altitude adaptation on the multifocal electroretinogram

Peter Kristian Kofoed, Birgit Sander, Gustavo Zubieta-Calleja, Line Kessel, Kristian Klemp, Michael Larsen, Peter Kristian Kofoed, Birgit Sander, Gustavo Zubieta-Calleja, Line Kessel, Kristian Klemp, Michael Larsen

Publikation: Bidrag til tidsskrift › Tidsskriftartikel › Forskning › peer review

9 Citationer (Scopus)

Abstract

Udgivelsesdato: 2009-Aug

Originalsprog	Engelsk
Tidsskrift	Investigative Ophthalmology & Visual Science
Vol/bind	50
Udgave nummer	8
Sider (fra-til)	3964-9
Antal sider	6
ISSN	0146-0404
DOI	https://doi.org/10.1167/iovs.08-3216 https://doi.org/10.1167/iovs.08-3216
Status	Udgivet - 1 aug. 2009

Bibliografisk note

Keywords: Acclimatization; Adult; Altitude; Blood Glucose; Electroretinography; Erythrocyte Count; Female; Hematocrit; Hemoglobins; Humans; Intraocular Pressure; Male; Oxygen; Oxygen Consumption; Retina

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Citationsformater

Kofoed, P. K., Sander, B., Zubieta-Calleja, G., Kessel, L., Klemp, K., Larsen, M., Kofoed, P. K., Sander, B., Zubieta-Calleja, G., Kessel, L., Klemp, K., & Larsen, M. (2009). The effect of high- to low-altitude adaptation on the multifocal electroretinogram. Investigative Ophthalmology & Visual Science, 50(8), 3964-9. https://doi.org/10.1167/iovs.08-3216, https://doi.org/10.1167/iovs.08-3216

Kofoed, PK, Sander, B, Zubieta-Calleja, G, Kessel, L, Klemp, K, Larsen, M, Kofoed, PK, Sander, B, Zubieta-Calleja, G, Kessel, L, Klemp, K & Larsen, M 2009, 'The effect of high- to low-altitude adaptation on the multifocal electroretinogram', Investigative Ophthalmology & Visual Science, bind 50, nr. 8, s. 3964-9. https://doi.org/10.1167/iovs.08-3216, https://doi.org/10.1167/iovs.08-3216

@article{c420eb207ac211df928f000ea68e967b,

title = "The effect of high- to low-altitude adaptation on the multifocal electroretinogram",

abstract = "PURPOSE: To examine variations in retinal electrophysiology assessed by multifocal electroretinogram (mfERG) during acclimatization of native highlanders to normobaric normoxia at sea level. METHODS: Eight healthy residents of the greater La Paz area in Bolivia (3600 m above sea level) were examined over 72 days after arriving in Copenhagen, Denmark (sea level). A control group of eight healthy lowlanders was used for comparison. RESULTS: During the period of observation, hemoglobin decreased from 16.7 to 15.0 g/dL (P = 0.0031), erythrocytes decreased from 5.3 to 4.6 trillion cells/L (P = 0.0006), and hematocrit decreased from 49.4% to 42.2% (P = 0.0008). At baseline, day 2 after arrival, the amplitudes (N1, P1, and N2) of the mfERG were 43.1% to 59.9% higher in the highlanders than in the lowlanders (P < 0.017). During acclimatization, the mfERG amplitudes increased 16.9% to 20.4% (P < 0.028) to a level of 73.2% to 87.0% higher in the highlanders than in the lowlanders (P < 0.0008). The increase in numerical amplitudes was proportional to the decrease in erythrocyte concentration (P = 0.023, 0.053, and 0.12 for N1, P1, and N2, respectively). CONCLUSIONS: On arrival at sea level, the highlanders had markedly supernormal multifocal electroretinographic amplitudes that continued to increase during the 72-day period of observation where the highlanders' hematocrit normalized. The results suggest that acclimatization after a change in altitude and hence in ambient oxygen tension involves intrinsic retinal mechanisms and that acclimatization was not complete by the end of the study.",

author = "Kofoed, {Peter Kristian} and Birgit Sander and Gustavo Zubieta-Calleja and Line Kessel and Kristian Klemp and Michael Larsen and Kofoed, {Peter Kristian} and Birgit Sander and Gustavo Zubieta-Calleja and Line Kessel and Kristian Klemp and Michael Larsen",

note = "Keywords: Acclimatization; Adult; Altitude; Blood Glucose; Electroretinography; Erythrocyte Count; Female; Hematocrit; Hemoglobins; Humans; Intraocular Pressure; Male; Oxygen; Oxygen Consumption; Retina",

year = "2009",

month = aug,

day = "1",

doi = "10.1167/iovs.08-3216",

language = "English",

volume = "50",

pages = "3964--9",

journal = "Investigative Ophthalmology & Visual Science",

issn = "0146-0404",

publisher = "Association for Research in Vision and Ophthalmology",

number = "8",

}

TY - JOUR

T1 - The effect of high- to low-altitude adaptation on the multifocal electroretinogram

AU - Kofoed, Peter Kristian

AU - Sander, Birgit

AU - Zubieta-Calleja, Gustavo

AU - Kessel, Line

AU - Klemp, Kristian

AU - Larsen, Michael

AU - Kofoed, Peter Kristian

AU - Sander, Birgit

AU - Zubieta-Calleja, Gustavo

AU - Kessel, Line

AU - Klemp, Kristian

AU - Larsen, Michael

N1 - Keywords: Acclimatization; Adult; Altitude; Blood Glucose; Electroretinography; Erythrocyte Count; Female; Hematocrit; Hemoglobins; Humans; Intraocular Pressure; Male; Oxygen; Oxygen Consumption; Retina

PY - 2009/8/1

Y1 - 2009/8/1

N2 - PURPOSE: To examine variations in retinal electrophysiology assessed by multifocal electroretinogram (mfERG) during acclimatization of native highlanders to normobaric normoxia at sea level. METHODS: Eight healthy residents of the greater La Paz area in Bolivia (3600 m above sea level) were examined over 72 days after arriving in Copenhagen, Denmark (sea level). A control group of eight healthy lowlanders was used for comparison. RESULTS: During the period of observation, hemoglobin decreased from 16.7 to 15.0 g/dL (P = 0.0031), erythrocytes decreased from 5.3 to 4.6 trillion cells/L (P = 0.0006), and hematocrit decreased from 49.4% to 42.2% (P = 0.0008). At baseline, day 2 after arrival, the amplitudes (N1, P1, and N2) of the mfERG were 43.1% to 59.9% higher in the highlanders than in the lowlanders (P < 0.017). During acclimatization, the mfERG amplitudes increased 16.9% to 20.4% (P < 0.028) to a level of 73.2% to 87.0% higher in the highlanders than in the lowlanders (P < 0.0008). The increase in numerical amplitudes was proportional to the decrease in erythrocyte concentration (P = 0.023, 0.053, and 0.12 for N1, P1, and N2, respectively). CONCLUSIONS: On arrival at sea level, the highlanders had markedly supernormal multifocal electroretinographic amplitudes that continued to increase during the 72-day period of observation where the highlanders' hematocrit normalized. The results suggest that acclimatization after a change in altitude and hence in ambient oxygen tension involves intrinsic retinal mechanisms and that acclimatization was not complete by the end of the study.

AB - PURPOSE: To examine variations in retinal electrophysiology assessed by multifocal electroretinogram (mfERG) during acclimatization of native highlanders to normobaric normoxia at sea level. METHODS: Eight healthy residents of the greater La Paz area in Bolivia (3600 m above sea level) were examined over 72 days after arriving in Copenhagen, Denmark (sea level). A control group of eight healthy lowlanders was used for comparison. RESULTS: During the period of observation, hemoglobin decreased from 16.7 to 15.0 g/dL (P = 0.0031), erythrocytes decreased from 5.3 to 4.6 trillion cells/L (P = 0.0006), and hematocrit decreased from 49.4% to 42.2% (P = 0.0008). At baseline, day 2 after arrival, the amplitudes (N1, P1, and N2) of the mfERG were 43.1% to 59.9% higher in the highlanders than in the lowlanders (P < 0.017). During acclimatization, the mfERG amplitudes increased 16.9% to 20.4% (P < 0.028) to a level of 73.2% to 87.0% higher in the highlanders than in the lowlanders (P < 0.0008). The increase in numerical amplitudes was proportional to the decrease in erythrocyte concentration (P = 0.023, 0.053, and 0.12 for N1, P1, and N2, respectively). CONCLUSIONS: On arrival at sea level, the highlanders had markedly supernormal multifocal electroretinographic amplitudes that continued to increase during the 72-day period of observation where the highlanders' hematocrit normalized. The results suggest that acclimatization after a change in altitude and hence in ambient oxygen tension involves intrinsic retinal mechanisms and that acclimatization was not complete by the end of the study.

U2 - 10.1167/iovs.08-3216

DO - 10.1167/iovs.08-3216

M3 - Journal article

C2 - 19234353

SN - 0146-0404

VL - 50

SP - 3964

EP - 3969

JO - Investigative Ophthalmology & Visual Science

JF - Investigative Ophthalmology & Visual Science

IS - 8

ER -