Abstract

Background: Age and high altitude affect hematological parameters. The purpose of this study was to evaluate the combined effect of age and altitude on hemoglobin (Hb) and red cell parameters.

Methods: In this cross-sectional comparative study, a large data set of complete blood counts, of both genders were retrospectively reviewed. Data were collected from two geographical areas; a moderately high-altitude, Abha city, 2270 meters above sea level, and a coastal Jeddah city, Saudi Arabia. Data were stratified into two age groups for both cities i.e. 12-60 years and 61-100 years. For all CBC parameters, descriptive analysis and multivariate regression analysis was carried out.

Results: Hemoglobin levels of males and females at Abha was high as compared to their counterparts at Jeddah. At both cities, females maintained their hemoglobin concentration and showed slightly increase after menopause while males showed gradual decline in their hemoglobin concentration with aging. Overall, Hb levels had highly significant negative linear relationship (p ＜ 0.01) with age (r = -0.015) and gender (r = -0.182) while positive liner relationship with altitude (r = 0.071). While comparing Hb in both cities, Jeddah population had more negative linear relationship (r = -0.011) with age than the Abha population (r = -0.014) suggesting that altitude effect on hemoglobin level remains robust despite aging.

Conclusion: Hemoglobin levels are affected by independent variables i.e. age, gender and altitude. Hemoglobin concentration declines with aging, however the positive effect of altitude on hemoglobin concentration remains robust in both genders even at older age groups (80-100).