THE LEVELS OF SERUM CORTISOL IN HIGH ALTITUDE PULMONARY OEDEMA – IS IT THE CAUSE

Dr. K S Brar, Dr. Naresh Bansal, Dr. Rakhi Malhotra, Dr. Amit Sreen, Dr. Anurag Roy

Abstract


Background: Cortisol is a physiological stress hormone and response of cortisol to high altitude exposure is dynamic influenced both by duration of exposure and exertion. It steadily increases following high altitude exposure or exercise and gradually plateaus on prolonged stay in high altitude areas. The variations in physiological cortisol response may have a pathological influence on High Altitude Pulmonary Oedema (HAPO) development. This study was carried out to test whether individuals who developed HAPO had a poor physiological stress cortisol response on exposure to high altitude.

Methods: Thirty patients admitted with HAPO along with thirty healthy controls who rapidly ascended to a high altitude were recruited in the study. The serum cortisol levels was estimated at the time of admission with HAPO and from healthy controls on 2nd or 3rd day of high altitude induction. The subjects (both patients and controls) were also subjected to ACTH stimulation test to determine adequacy of stress cortisol response as results of initial cortisol assay were not available. All subjects with one hour post ACTH cortisol response <18 mg/dL or incremental cortisol rise <9 mg/dL were diagnosed as having poor cortisol response.

Results: The study carried out on two comparative groups showed no difference in basal or Post ACTH cortisol on exposure to high altitude in patients who had developed HAPO from those who did not. The mean increment in serum cortisol or the Delta cortisol was also similar between two groups. The beneficial effect of Dexamethasone in HAPO is not due to relative adrenal insufficiency but due to its potent anti-inflammatory effects, enhanced alveolar fluid clearance and stabilisation of pulmonary endothelial membranes.      

Conclusion: The altitude-induced rise of many hormones provides evidence that acute exposure to hypoxia tends to stimulate the neuroendocrine system. The serum cortisol levels in our study showed no difference in HAPO patients and the controls. Although drugs are frequently used to prevent or treat high altitude illness, the primary recommendation to decrease its incidence is staged/gradual ascent and progressive acclimatization while cornerstone of its treatment by gradual and passive descent to lower altitude and oxygenation. The steroids only act via its potent anti-inflammatory effects, enhanced alveolar fluid clearance and stabilisation of pulmonary endothelial membranes.   


Keywords


High Altitude Pulmonary Oedema (HAPO), Cortisol, Post ACTH Cortisol, High altitude

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References


Basnyat B, Murdoch DR. High-altitude illness. Lancet 2003;361: 1967-1974.

Carpenter T, Reeves JT, Durmowicz AG. Viral respiratory infection increases susceptibility of young rats to hypoxia-induced pulmonary edema. J Appl Physiol. 1998;84:1048-1054.

Bärtsch P, Mairbäurl H, Maggiorini M, Swenson ER. Physiological aspects of high-altitude pulmonary edema. J Appl Physiol 1985;98: 1101-1110.

Basnyat B. High altitude cerebral and pulmonary edema. Travel Med Infect Dis 2005;3:199-211.

Schoene RB. Unraveling the mechanism of high altitude pulmonary edema. High Alt Med Biol 2004;5:125-135.

Maggiorini M. High altitude-induced pulmonary oedema. Cardiovasc Res 2006;72:41-50.

Scherrer U, Rexhaj E, Jayet PY, Allemann Y, Sartori C. New insights in the pathogenesis of high-altitude pulmonary edema. Prog Cardiovasc Dis 2010;52:485-492.

Maggiorini M, Melot C, Pierre S, Pfeiffer F, Greve I, Sartori C, et al. High-altitude pulmonary edema is initially caused by an increase in capillary pressure. Circulation. 2001;103:2078-83.

Mairbaurl H, Schwobel F, Hoschele S, Maggiorini M, Gibbs S, Swenson ER, et al. Altered ion transporter expression in bronchial epithelium in mountaineers with high-altitude pulmonary edema. J Appl Physiol. 2003;95:1843-50.

Zaccaria M, Rocco S, Noventa D, Varnier M, Opocher G. Sodium regulating hormones at high altitude:basal and post–exercise levels. J Clin Endocrin Metab 1998; 83:570-4.

Sutton JR, Viol GW, Gray GW, McFadden M, Keane PM. Renin, aldosterone, electrolyte, and cortisol responses to hypoxic decompression. J Appl Physiol 1977; 43: 421-424.

Richalet JP, Rutgers V, Bouchet P et al. Diurnal variations of acute mountain sickness, colour vision, and plasma cortisol and ACTH at high altitude. Aviat Space Environ Med 1989; 60:105-11.

Smith TJ, Grediagin A, Kellogg MD et al. Salivary Cortisol Response in Physically Active Males at High Altitude (4300 M). Med Sci Sports & Exercise 2004; 36: S108.

Humpeler E, Skrabal F, Bartsch G. Influence of exposure to moderate altitude on the plasma concentration of cortisol, aldosterone, renin, testosterone, and gonadotropins. Eur J Appl Physiol 1980; 45: 167–176.

Anand IS, Chandrashekhar Y, Rao SK et al. Body fluid compartments, renal blood flow, and hormones at 6,000 m in normal subjects. J Appl Physiol 1993; 74: 1234–1239.

Grieg WR, Maxwell JD, Boyle JA, Lindsay RM, Browning MCK. Criteria for distinguishing normal from subnormal adrenocortical function using the Synacthen test. Postgrad Med J 1969;45:307-313.

Pennardt A. High-altitude pulmonary edema: diagnosis, prevention, and treatment. Curr Sports Med Rep 2013;12:115-119.

Oelz O, Maggiorini M, Ritter M, Waber U, Jenni R, Vock P, et al. Nifedipine for high altitude pulmonary oedema. Lancet. 1989;2:1241-4.

Maher JT, Jones LG, Hartley LH, Williams GH, Rose LI. Aldosterone dynamics during graded exercise at sea level and high altitude J Appl Physiol 1975; 39: 18-22.


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