Effect of Altitude on Hemoglobin and Red Blood Cell Indices in Adults in Different Regions of Saudi Arabia

Abstract

Husain Y Alkhaldy,1,2 Zuhier A Awan,3,4 Ahmed A Abouzaid,4,5 Hossameldin M Elbahaey,4,6 Saeed M Al Amoudi,5 Shehata F Shehata,7,8 Muhammad Saboor9,10 1Department of Internal Medicine, College of Medicine, King Khalid University, Abha, Saudi Arabia; 2Research Center for Advanced Materials Science, King Khalid University, Abha, Saudi Arabia; 3Department of Clinical Biochemistry, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia; 4Department of Clinical Pathology, Al-Borg Medical Laboratories, Jeddah, Saudi Arabia; 5Department of Medical Biochemistry, Faculty of Medicine, Al-Azhar University, Cairo, Egypt; 6Clinical Pathology Department, Suez Canal University, Ismailia Governorate, Egypt; 7Department of Community Medicine, College of Medicine, King Khalid University, Abha, Saudi Arabia; 8High Institute of Public Health, Alexandria University, Alexandria, Egypt; 9Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, Jazan University, Jazan, Saudi Arabia; 10Medical Research Center, Jazan University, Jazan, Saudi ArabiaCorrespondence: Husain Y Alkhaldy, Department of internal medicine, College of Medicine, King Khalid University, P.O.BOX 641, Abha, 61421, Saudi Arabia, Tel [phone], Fax [phone], Email [email protected] Muhammad Saboor, Department of Medical Laboratory Technology, Faculty of Applied Medical Science, Jazan University, Jazan, Saudi Arabia, Tel [phone], Email [email protected]: Complete blood count (CBC) is a commonly used blood test for health checks. This study was conducted to compare CBC from two different altitudes and from sea-level populations in order to suggest correction factor for altitude-related increment on the hemoglobin and red blood cell indices.Patients and Methods: In this retrospective lab records study, large datasets of CBCs over 5-year period were screened from three different regions of Saudi Arabia, Jeddah (a coastal city), Taif City located at 1879 m above sea level, and Abha City at located 2270 m above sea level. Descriptive analysis and significance testing of the CBC variables at different altitude were compared.Results: A total of 57,059 participants were included for final analysis. Mean hemoglobin (Hb) concentration (g/dL) was 14.81 for men and 13.77 for women at sea level, whereas Hb concentrations were 15.35 and 14.19 for men and women residing at Taif City, respectively, and 15.40 and 14.71 for men and women at Abha City, respectively. Hemoglobin and other red cell indices were significantly different among men and women across different altitude, except for mean corpuscular volume (MCV). The MCV 95th percentile range was lower at sea level and both altitudes as compared to current reference range (76– 91 fL vs 81– 98 fL).Conclusion: Although altitude-associated increment in Hb concentration was evident in both men and women, it was lower than as suggested by World Health Organization and Centers for Disease and Control. Results of this study can also be used to derive new CBC reference intervals for Saudi residents living at high altitude. A correction factor (ΔHb) of 0.30 g/dL per 1000 m altitude is suggested to be used in adult population living at high altitudes in Saudi Arabia which should help better define anemia and polycythemia at altitude.Keywords: high altitude, reference interval, CBC

Keywords

• high altitude
• reference interval
• cbc