Ethnic Differences in the Incidence of Hypertension among Rural Chinese Adults: Results from Liaoning Province

BACKGROUND This study was conducted to examine the differences in the incidence of hypertension and associated risk factors between Mongolian and Han populations in northeast China. METHODS A population-based sample of 4753 Mongolian subjects and 20,247 Han subjects aged ≥ 35 years and free from hypertension at baseline were followed from 2004-2006 to 2010. Incident hypertension was defined as systolic blood pressure ≥ 140 mmHg, diastolic blood pressure ≥ 90 mmHg, or current use of antihypertensive medication. RESULTS During mean 4.3 years follow-up, a total of 8779 individuals developed hypertension. The age-adjusted incidence of hypertension for Mongolian subjects was 12.64 per 100 person-years, for Han subjects was 9.77 per 100 person-years (P<0.05). The incidence of hypertension was positively correlated with age, physical activity, drinking, body mass index (BMI), family of hypertension and prehypertension in the Han population. In the Mongolian population, hypertension was positively correlated with age, physical activity, education level, drinking, BMI, prehypertension and family history of hypertension. The rates of awareness, treatment and control of hypertension for newly developed cases among both Han and Mongolian populations were low. (36.5% vs. 42.3%, 13.1% vs. 18.2%, 0.7% vs. 1.3%, P<0.05, respectively). CONCLUSIONS The incidence rate of hypertension is higher in the Mongolian populations than that in the Han populations, and hypertension in both ethnic populations was associated with similar risk factors. Our results suggest that most newly-diagnosed cases of hypertension are not adequately treated. Improvements in hypertension prevention and control programs in rural China are urgently needed.