Regional Disparities in the Hypertension Risk in China: A Longitudinal Study

Context: Hypertension is a tremendous public health burden in China. The understanding of geographic variability in hypertension risk would help to optimize resource allocation and policy making. Objective: Examine the regional disparities in hypertension risk in China. Design: This is a longitudinal cohort study. Risk profiles of hypertension for eight east provinces in China were studied using generalized estimating equation approach with covariates adjustment of gender, age, urban residence, and BMI. Results: The analysis cohort included 7,710 participants with 30,934 observations, consisting of 3,918 (50.8%) men and 3,792 (49.2%) women from eight participating provinces which line up from south to north China. The prevalence of hypertension in this cohort increased from 15.1 to 32.2% from 1997 to 2009. The rate of awareness doubled to 43.7%, and the treatment rate among those being aware increased to 79%. However, among all hypertensive population there was only 10.1% people were controlled in 2009. Hypertension risk was found to be significantly higher in female, rural residents, older people, and be increasing with higher BMI. Adjusting for these risk factors, region was significant associated with hypertension risk over years. Adjusted odds ratios escalated from south to north of China. People from Heilongjiang, the most north province, had greatest odds having hypertension (odd ratio 2.4, 95% CI: 2.0 – 2.8). Conclusion: We found significant latitudinal disparities in the hypertension risk in China. The risk gradually escalates from south to north. This spatial pattern was not explained by effect of gender, age, urban/rural residence, and BMI.