Effect of Standard vs Intense Hypertension Management on Nighttime Blood Pressure

描述（由申请人提供）：高血压是心血管和肾脏疾病的主要危险因素，也是全球过早死亡的主要原因。早期高血压研究表明，治疗高血压可降低患者患心血管疾病的风险和全因死亡率。在随后的研究中，当患者的治疗目标是收缩压适中（<150mmHg）时，心血管预后的改善要大于收缩压较高的患者。虽然观察数据表明，更低的血压目标可能是有益的，但这还没有在随机试验中看到；相反，“高强度”高血压治疗（即目标收缩压<120mmHg）被发现对参与者患肾脏疾病、心血管疾病或全因死亡率的风险没有影响。一个可能的解释是，对于这种明显缺乏益处的高强度血压目标是研究

DESCRIPTION (provided by applicant): Hypertension is a major risk factor for cardiovascular and renal disease, and a leading cause of premature mortality worldwide. Early hypertension studies showed that treating elevated blood pressure (BP) reduces patients' risk of cardiovascular disease and all-cause mortality. In subsequent research, patients achieved greater improvement in cardiovascular outcomes when their treatment was aimed at a moderate systolic BP target (<150mmHg) than at higher targets. Although observational data suggest that even lower BP targets may be beneficial, this has not been seen in randomized trials; instead, "intense" treatment of hypertension (i.e., to a target systolic BP <120mmHg) was found to have no effect on participants' risk for renal disease, cardiovascular disease, or all-cause mortality. One potential explanation for this apparent lack of benefit of intense BP targets is that the study protocols targeted reductions in clinic BP rather than ambulatory BP. Ambulatory BP monitoring (ABPM) allows for assessment of BP throughout the day and night. Of all the BP measurements, nighttime systolic BP appears to be the best predictor of cardiovascular disease and all-cause mortality. Because recent trials assessing intense BP targets did not include ambulatory BP measurements, the effect of intensive treatment on nighttime BP is largely unknown. To address this important gap in knowledge, we will conduct ABPM in 950 participants as part of an ancillary study to the ongoing Systolic Blood Pressure Intervention Trial (SPRINT). The goal of the ancillary study is to evaluate the effect of intensive vs. standard clinic based BP targets on nighttime BP (primary outcome), as well as night/day BP ratio, timing of peak BP, 24hr BP, and BP variability (secondary outcomes). Regardless of the outcomes, completion of the proposed ancillary study will significantly impact the direction of future hypertension research. If intensive treatment of BP is associated with lower nighttime BP, then results from the parent SPRINT study will demonstrate the effect (positive or negative) of achieving lower nighttime BP on important cardiovascular and renal outcomes. Alternatively, negative overall SPRINT results coupled with an ancillary study finding of "no difference" in nighttime BP between the groups will indicate the need for future trials to determine whether lowering nighttime BP reduces the risk for CKD progression, end-stage renal disease, and cardiovascular disease. In addition, the proposed study will provide mechanistic insight into the primary SPRINT results by elucidating the effect of intense clinic BP targets on dipping, the timing of peak BP, and BP variability. Lastly, this ancillary study will provide the principal investigator with leadership experience within a large, ongoing clinical trial, thereby preparing the candidate for a career as an independent clinical researcher, with the long- term goal of reducing the morbidity and mortality associated with hypertension through therapies targeted to specific components of ambulatory BP.