Blood Pressure Changes While Hiking at Moderate Altitudes: A Prospective Cohort Study.

Ky B Stoltzfus,Tessa Cattermole,Rebecca Mount,Cheryl A Gibson,Rong Chang,David Naylor,Arthur Ankeney

doi:10.3390/ijerph17217978

Abstract

Recreational hiking in the mountains is a common activity, whether for a single day or for several days in a row. We sought to measure blood pressure (BP) response during a 10-day trek at moderate-altitude elevation (6500–13,000 feet) and observe for uncontrolled hypertension and/or adverse cardiovascular outcomes. A total of 1279 adult participants completed an observational study of resting BP during a 10-day trek in the Sangre de Cristo mountains. Following initial recruitment, participants were issued a trail data card to record BP measurements at day 0 (basecamp), day 3, day 6 and day 9. BP was measured using a sphygmomanometer and auscultation. Demographic data, height, weight, home altitude, daily water and sports drink intake, existence of pre-arrival hypertension and BP medication class were also recorded. We observed a rise in mean blood pressure for the cohort during all exposures to moderate altitudes. The increases were greatest for individuals with pre-existing hypertension and/or obesity. There were no observed life-threatening cardiovascular events for participants. We conclude that for individuals with a modestly controlled blood pressure of 160/95 mmHg, hiking at a moderate altitude is a safe activity.

Highlights

Hiking at elevated altitude is a popular outdoor activity in the United States and in many other countries
1279 of 2008 participants completed the study during the summer camping seasons of 2015 and 2016
Statistical significance level: * p < 0.05, ** p < 0.005, *** p < 0.001. In this relatively large prospective cohort study, we show that for most individuals hiking at moderate altitudes, resting blood pressure (BP) does not rise in a clinically significant manner for an individual

Summary

Introduction

Hiking at elevated altitude is a popular outdoor activity in the United States and in many other countries. Hiking at moderate altitudes of 1500–2500 m (4900–8000 feet) over one–three weeks has been shown to provide positive health effects for individuals with metabolic syndrome and healthy individuals [1]. Those with pre-existing hypertension have been found to be at increased risk of sudden death while taking ski vacations at high altitudes [2]. A recent joint statement of clinical recommendations for high-altitude exposure of individuals with pre-existing cardiovascular conditions outlines class II-B evidence for checking BP before and during hiking activity for individuals with moderate-severe hypertension [5]. It cites class I-C evidence for the safety of individuals with well-controlled hypertension to reach high altitude (>13,000 feet) and I-C evidence that uncontrolled hypertensive individuals avoid high-altitude exposure due to the risk of organ damage

Results

Discussion

Conclusion