Objective: To study the relationship between salt consumption and blood pressure among residents in Shandong province, and to provide basic information for guiding people to prevent hypertension by reducing salt intake.
Methods: Using multi-stage stratified cluster random sampling method, 2 184 residents aged 18 to 69 were selected as the research subjects, which were extracted randomly from 20 counties in Shandong province in June, 2011. The blood pressure of the subjects were measured and weighted. Based on 72 h dietary recalls and weighing measurement, and according to the distribution of salt intake, the grouping cut-off points were 10, 14 and 18 g. The difference of subjects with different characteristics and systolic blood pressure, diastolic blood pressure and prevalence of hypertension by grouping salt intake and other characteristics were analyzed, and the relationship between salt intake and prevalence of hypertension were analyzed.
Results: The total of 2 133 residents were involved finally, the completion rate was 97.7%. After the complex weighted, the systolic and diastolic blood pressure's means (95%CI value) of the subjects were 121.0 (119.5-122.5) mmHg (1 mmHg = 0.133 kPa) and 78.5(77.4-79.6) mmHg respectively, which were all elevated with increasing of salt consumption. The blood pressure of the subjects with salt intake <10 g was the lowest, which were 119.6 (116.9-122.4) mmHg and 77.5(76.2-78.7) mmHg respectively. The blood pressure of the subjects with salt intake ≥ 18 g was the highest, which were 122.3(120.1-124.5) mmHg and 79.6(78.2-80.9) mmHg respectively. The analysis results showed that, among residents with normal waistline, the prevalence of hypertension of people with salt intake ≥ 18 g was 1.70(95%CI:1.04-2.76) times compared to that of people who consumed less than 10 g salt per day.
Conclusion: The hypertension prevalence of Shandong province is quite high, and there is a relationship between salt consumption and blood pressure.