The effect of altitude on blood pressure in the Assir Province of Saudi Arabia

Measurements of normal blood pressure, body weight, height, and packed cell volume (PCV) were made in healthy, normal Saudi Arab adult males who were born and were living permanently at high altitude (3150 m) in southern Saudi Arabia. These values were compared with those obtained from healthy, normal Saudi Arab adult males born and living permanently at low altitude (500 m). Results showed that residents at high altitude were significantly heavier, taller, and have higher PCV than their lowland counterparts. Their mean body mass index (BMI) values were not significantly different. Small but significant increases in systolic blood pressure (SBP) and diastolic blood pressure (DBP) were observed in high-altitude residents (112 and 75 mm Hg, respectively) when compared with low altitude residents (109 and 71 mm Hg, respectively) (p < .001 for both SBP and DBP). The differences in blood pressures between highlanders and lowlanders were attributed to the significantly higher body weight and packed cell volume in the highlanders. The results are discussed in relation to available information on blood pressure in residents at high altitude. © 1995, Wilderness Medical Society. All rights reserved.