OBJECTIVETo explore the risk factors of hypertension and risk population for adults aged > or = 25 in the mid-western rural areas of Shandong province and to provide evidence for development of intervention measure.

METHODSSubjects aged > or = 25 were selected by multi-stage stratified random sampling method. All participants were interviewed with a standard questionnaire and physically examined on height, weight, waist circumference, blood pressure and fasting plasma glucose (FPG). Classification tree analysis was employed to determine the risk factors of hypertension and high risk populations related to it.

RESULTSThe major risk factors of hypertension would include age, abdominal obesity, overweight or obesity, family history and high blood sugar. The major populations at high risk would include populations as: a) being elderly, b) at middle-age but with: high blood sugar or with abdominal obesity/overweight, or with family history, c) people at middle-age but with family history and abdominal obesity. Through classification tree analysis, sensitivity, specificity and overall correct rates were 71.87%, 66.38% and 68.79%, respectively on 'learning sample' while 70.70%, 65.84% and 67.97% respectively on 'testing sample'.

CONCLUSIONEfforts on both weight and blood sugar reduction were common prevention measures for general population. Different kinds of prevention and control measures should be taken according to different risk factors existed in the targeted high-risk population of hypertension. Community-based prevention and control for hypertension measures should be integrated when targeting the population at high risk.