Maruthur Nisa M, Wang Nae-Yuh, Appel Lawrence J
Division of General Internal Medicine and the Welch Center for Prevention, Epidemiology, and Clinical Research, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
Circulation. 2009 Apr 21;119(15):2026-31. doi: 10.1161/CIRCULATIONAHA.108.809491. Epub 2009 Apr 6.
Although trials of lifestyle interventions generally focus on cardiovascular disease risk factors rather than hard clinical outcomes, 10-year coronary heart disease (CHD) risk can be estimated from the Framingham risk equations. Our objectives were to study the effect of 2 multicomponent lifestyle interventions on estimated CHD risk relative to advice alone and to evaluate whether differences can be observed in the effects of the lifestyle interventions among subgroups defined by baseline variables.
A total of 810 healthy adults with untreated prehypertension or stage I hypertension were randomized to 1 of 3 intervention groups: An "advice-only" group, an "established" group that used established lifestyle recommendations for blood pressure control (sodium reduction, weight loss, and increased physical activity), or an "established-plus-DASH" group that combined established lifestyle recommendations with the DASH (Dietary Approaches to Stop Hypertension) diet. The primary outcome was 10-year CHD risk, estimated from follow-up data collected at 6 months. A secondary outcome was 10-year CHD risk at 18 months. Of the 810 participants, 62% were women and 34% were black. Mean age was 50 years, mean systolic/diastolic blood pressure was 135/85 mm Hg, and median baseline Framingham risk was 1.9%. The relative risk ratio comparing 6-month to baseline Framingham risk was 0.86 (95% confidence interval 0.81 to 0.91, P<0.001) in the established group and 0.88 (95% confidence interval 0.83 to 0.94, P<0.001) in the established-plus-DASH group relative to advice alone. Results were virtually identical in sensitivity analyses, in each major subgroup, and at 18 months.
The observed reductions of 12% to 14% in estimated CHD risk are substantial and, if achieved, should have important public health benefits.
尽管生活方式干预试验通常关注心血管疾病风险因素而非确切的临床结局,但可通过弗明汉风险方程估算10年冠心病(CHD)风险。我们的目标是研究两种多成分生活方式干预相对于单纯建议对估算的冠心病风险的影响,并评估在由基线变量定义的亚组中生活方式干预的效果是否存在差异。
总共810名未经治疗的高血压前期或I期高血压健康成年人被随机分配到3个干预组中的1组:“仅建议”组、采用既定生活方式建议控制血压(减少钠摄入、减重和增加体力活动)的“既定”组,或结合既定生活方式建议与DASH(终止高血压饮食疗法)饮食的“既定+DASH”组。主要结局是根据6个月时收集的随访数据估算的10年冠心病风险。次要结局是18个月时的10年冠心病风险。在810名参与者中,62%为女性,34%为黑人。平均年龄为50岁,平均收缩压/舒张压为135/85 mmHg,基线弗明汉风险中位数为1.9%。相对于单纯建议,“既定”组6个月时与基线弗明汉风险相比的相对风险比为0.86(95%置信区间0.81至0.91,P<0.001),“既定+DASH”组为0.88(95%置信区间0.83至0.94,P<0.001)。在敏感性分析、每个主要亚组以及18个月时,结果基本相同。
观察到的估算冠心病风险降低12%至14%幅度很大,如果实现,应具有重要的公共卫生益处。