Characteristics and Risk Factors of Hypertension among Residents on the Qinghai-Tibetan Plateau

The relationship between blood pressure (BP) and high altitude is still controversial. Few studies have compared the prevalence of hypertension between plateau-native group (PNG) and non-plateau-native group (nPNG) populations at the same altitude. We explored the characteristics and risk factors for hypertension among residents on the Qinghai-Tibetan Plateau. From 2014 to 2019, the blood pressure of 6987 PNG and nPNG ≥ 18 years of age in Qinghai, China, was analyzed. Participants were divided into three groups by altitude: the 2000~2999-meter, 3000~3999-meter and ≥4000-meter groups. The association between altitude and BP was assessed by univariate and multivariate logistic regression. The prevalence of hypertension among residents on the Qinghai-Tibetan Plateau was approximately 30.53%. We found a V-shaped association between altitude and blood pressure and an inverted V-shaped association between altitude and the prevalence of sinus bradycardia (SB). Both systolic blood pressure (SBP) levels and diastolic blood pressure (DBP) levels in the 3000~3999-meter PNG group were lower than those in the nPNG group at the same altitude (P<0.05). Multivariate regression analysis showed that the hypertension risk factors at high altitudes were age, altitude, body mass index (BMI), abnormal total cholesterol (TC) levels, abnormal high-density lipoprotein cholesterol levels, abnormal hemoglobin levels, alcohol consumption and sinus bradycardia. We concluded that the relationship between hypertension prevalence and altitude among residents living at high altitudes had a V-shaped distribution. Risk factors for hypertension varied with altitude. Participants in the PNG exhibited better adaptation at 3000~3999 meters; at altitudes above 4000 meters, the adaptation advantages of the PNG disappeared.