[The relationship between physical activity and incident hypertension in rural Chinese].

Objective: To investigate the relationship between physical activity (PA) and the risk of incident hypertension among population in rural areas of China. Methods: The Community Intervention of Metabolic Syndrome in China & Chinese Family Health Study (CIMIC) was conducted in 2007-2008. Data on PA, smoking, drinking, blood pressure and other variables were obtained at baseline. Then the follow-up study of incident hypertension was performed during 2012-2015. A total of 41 457 participants aged ≥18 years and free from hypertension at baseline were included in the final analyses. PA was calculated as metabolic equivalent (MET) for each participant. Cox proportional hazard models were used to explore the relationship of PA with incident hypertension according to the quartiles of PA. Results: A total of 6 780 participants developed hypertension during an average follow up of 5.8 years. The annual incidence of hypertension was 2.80%. Compared to participants in the first quartile of PA, HR (95%CI) of incident hypertension decreased with the level of PA of 0.92 (0.86, 0.99), 0.72 (0.67, 0.77) and 0.70 (0.65, 0.75) for the 2(nd), 3(rd) and 4(th) quartile, respectively (P(trend)<0.001). In subgroup analyses, compared to the first quartile, hazards of hypertension among normotensive participants (systolic blood pressure less than 120 mmHg (1 mmHg=0.133 kPa) and diastolic blood pressure less than 80 mm Hg) in the 2(nd), 3(rd) and 4(th) quartile were 0.82 (0.70, 0.95), 0.73 (0.63, 0.85) and 0.78 (0.67, 0.90), respectively (P(trend)=0.002). Among participants with prehypertension (systolic blood pressure from 120 to 139 mmHg and/or diastolic blood pressure from 80 to 89 mmHg), similar trend for the relationship of PA and incident hypertension was also found with HR (95%CI) of 0.94 (0.87, 1.01), 0.71 (0.65, 0.77) and 0.66 (0.61, 0.71) for the 2(nd), 3(rd) and 4(th) quartile, respectively (P(trend)<0.001). Conclusion: There was linear trend association between PA and incident hypertension. Increased PA in daily life may be a protective factor against hypertension.目的： 探讨我国农村地区居民总体力活动水平与高血压发病的关系。 方法： 利用2007—2008年进行的中国代谢综合征社区干预研究暨中国家庭健康研究（CIMIC）队列人群，收集研究对象的基线体力活动、吸烟、饮酒、血压水平等信息，并于2012—2015年对该人群的高血压发病情况进行随访。研究纳入41 457名18岁及以上基线无高血压个体。以代谢当量（MET）计算研究对象总体力活动并采用四分位数法分组，采用Cox比例风险模型分析总体力活动与高血压发病风险的关系。 结果： 平均随访5.8年，高血压新发病例共6 780例，年发病率为2.80%。以总体力活动最低（QR1）组作为参照，总体力活动水平较低（QR2）、中等（QR3）和最高（QR4）组个体的高血压发病风险均降低，HR（95%CI）值分别为0.92（0.86~0.99）、0.72（0.67~0.77）和0.70（0.65~0.75）（P(趋势)<0.001）。在理想血压组[收缩压<120 mmHg（1 mmHg=0.133 kPa）和舒张压<80 mmHg]中，以总体力活动最低（QR1）组作为参照，QR2~QR4组研究对象的高血压发病风险均降低，HR（95%CI）值分别为0.82（0.70~0.95）、0.73（0.63~0.85）和0.78（0.67~0.90）（P(趋势)=0.002）。在正常高值血压组（收缩压120~139 mmHg和/或舒张压80~89 mmHg），高血压发病风险随体力活动水平升高而下降（P(趋势)<0.001），体力活动水平QR2~QR4组的高血压发病风险HR（95%CI）值分别为0.94（0.87~1.01）、0.71（0.65~0.77）和0.66（0.61~0.71）。 结论： 随着体力活动总量增加，高血压发病风险逐渐降低，且存在线性趋势；增加体力活动对于预防高血压发病具有保护性作用。.