The overestimated prevalence of hypertension in a population survey: a cross-sectional study from Hebei province, China

Objective: Currently, the prevalence of hypertension is mainly ascertained using a one-visit population survey, which may lead to overestimation. The purpose of this study was to assess the accuracy of hypertension prevalence determined by a one-visit population survey.

Methods: For this cross-sectional study, we continuously enrolled 1116 volunteers without a hypertension history in Hebei province from January 2018 to December 2019. The study population included 511 (45.80%) males and 605 (54.20%) females with a mean age of 48 years. The hypertension prevalence was assessed using two methods: one-visit screening and daytime ambulatory blood pressure (BP) monitoring. We directly compared the performances of daytime ambulatory BP monitoring and one-visit screening in the same group of subjects. In addition, we explored possible thresholds to improve the detection of hypertension.

Results: During the one-visit survey, the mean BP value was about 8 mmHg higher than that determined by daytime ambulatory BP monitoring. The prevalence of hypertension was 29.84% and 14.07% during the one-visit and daytime multiple visit surveys, respectively. The risk factors for overestimated hypertension were female sex, body mass index < 24.00 kg/m², and diastolic BP of 100 mmHg. The positive predictive value of the one-visit population survey for diagnosing hypertension was 36.34%. Furthermore, receiver operating characteristic analysis showed that in males, the best diagnostic threshold for hypertension diagnosis was 148/96 mmHg.

Conclusion: The hypertension prevalence was likely overestimated by 2-fold in the one-visit survey group compared to the daytime ambulatory BP monitoring group. Thus, the threshold for one-visit BP screening should be raised to 148/96 mmHg to improve the accuracy of hypertension diagnosis.