Prevalence of hypertension subtypes in 2011 and the trends from 1991 to 2011 among Chinese adults

Background This study aims to estimate the current prevalence and trends of hypertension subtypes among Chinese adults from 1991 to 2011. Methods We analysed the measurements of systolic and diastolic blood pressure among adults aged >= 18 years from the China Health and Nutrition Survey (CHNS) 1991-2011. The prevalence was age-adjusted to the 2010 census of Chinese adults. Results The adjusted prevalence in 2011 was 20.9% (95% CI 20.2% to 21.6%) of hypertension, 3.30% (95% CI 2.99% to 3.62%) of isolated systolic hypertension, 4.44% (95% CI 4.08% to 4.80%) of isolated diastolic hypertension, 4.11% (95% CI 3.76% to 4.46%) of systolic-diastolic hypertension and 9.01% (95% CI 8.51% to 9.51%) of current use of antihypertensive medication, respectively. From 1991 to 2011, the prevalence increased from 15.6% to 20.9% for hypertension (p<0.001) and from 3.04% to 3.30% for isolated systolic hypertension (p<0.001). However, the prevalence decreased from 4.77% to 4.44% for isolated diastolic hypertension (p=0.023) and from 5.27% to 4.11% for systolic-diastolic hypertension (p<0.001). Consistent with these findings, the percentage of current use of antihypertensive medication increased from 2.55% to 9.01%, which accounted for approximately 43.1% of the total number of cases in 2011. Importantly, only 36.9% (equivalent to 17.5% of the total number of hypertensive people) of cases of current use of antihypertensive medication were adequately controlled. Conclusions Both the prevalence of hypertension and the percentage of current use of antihypertensive medication significantly increased from 1991 to 2011. Currently, about one-fifth of Chinese adults are hypertensive; however, only 17.5% of hypertension is controlled.