Prevalence and risk factors associated with hypertension and prehypertension in a working population at high altitude in China: a cross-sectional study

BACKGROUND Little information is available on the epidemiology of hypertension and prehypertension at high altitude in China, the aim of this study was to determine the prevalence of hypertension, prehypertension and their risk factors among Chinese working population at high altitude regions. METHODS A cross-sectional survey was performed in an occupational sample of 4198 employees aged 20-59 years on Qinghai-Tibet Plateau between May to July 2013. Information from a self-administered questionnaire, physical examinations and laboratory measurements were obtained from each participant. Multivariable analysis was performed to determine the association of various risk factors with hypertension and prehypertension. RESULTS The total crude prevalence of hypertension and prehypertension was 28.1 and 41.5%, respectively; the overall standardized prevalence of hypertension and prehypertension was 26.7 and 41.3%, respectively. Multivariate logistic regression showed that age, sex, ethnicity, job position, overweight or obesity, frequent drinking, family history of hypertension, diabetes and hyperuricemia were risk factors for hypertension, and age, sex, education, job position, overweight or obesity, current smoking and family history of hypertension were risk factors for prehypertension. Among the hypertensives, 36.5% were aware of their condition, 19.4% were being treated and 6.2% had their blood pressure (BP) controlled; among the treated hypertensives, 31.9% had their BP under control. CONCLUSIONS There is a high prevalence of hypertension and prehypertension in the working population at high altitude in China, but with very low awareness, treatment and control rates. Workplace-based BP screening and intervention programs that aim to modify risk factors such as high BMI, tobacco use, alcohol consumption and inappropriate use of antihypertensive medicine are urgently needed.