Devonshire Ashley L, Hager Erin R, Black Maureen M, Diener-West Marie, Tilton Nicholas, Snitker Soren
Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland, USA.
Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA.
BMC Public Health. 2016 Jan 26;16:78. doi: 10.1186/s12889-016-2717-6.
To improve understanding of the pathophysiology of hypertension in adolescents and pave the way for risk stratification, studies have sought to determine the correlates of blood pressure (BP). Inconsistencies in dependent and independent variables have resulted in an elusive consensus. The aim of this report is to examine an inclusive array of correlates of BP, as a continuous (systolic and diastolic BP) and a dichotomous variable.
Subjects were a school-based sample of 730 urban, mostly African American, non-referred 6th and 7th grade girls. To find independent correlates of SBP/DBP, we used a stepwise model selection method based on the Schwarz Bayesian Information Criterion, enabling selection of a parsimonious model among highly correlated covariates. Candidate variables were: age, stature, heart rate, pubertal development, BMI, BMI z-score, waist circumference, waist-to-height ratio (WHtR), body surface area, fat mass (by bioelectrical impedance analysis), fat-free mass (FFM), percentage of body fat, and presence of overweight/obesity.
The best-fitting models for DBP and SBP (considered separately) included fat-free mass, heart rate and, in the case of SBP, stature. The best-fitting model for high-normal/elevated blood pressure (H-N/EBP) included WHtR with no independent relation of any other variable. The prevalence of H-N/EBP tripled between a WHtR of 0.5 and 0.7.
The easily obtained and calculated WHtR is the strongest correlate of elevated blood pressure among available variables and is a prime candidate for longitudinal studies of predictors of the development of hypertension.
ClinicalTrials.gov Identifier, NCT00746083.
为了增进对青少年高血压病理生理学的理解并为风险分层铺平道路，多项研究试图确定血压（BP）的相关因素。因自变量和因变量不一致，尚未达成明确共识。本报告旨在研究一系列与血压相关的因素，包括连续性变量（收缩压和舒张压）和二分变量。
研究对象为730名城市6、7年级女生，以学校为抽样单位，她们大多为非裔美国人，且未被转诊。为找出收缩压/舒张压的独立相关因素，我们采用基于施瓦茨贝叶斯信息准则的逐步模型选择方法，以便在高度相关的协变量中选择一个简约模型。候选变量包括：年龄、身高、心率、青春期发育、体重指数（BMI）、BMI z评分、腰围、腰高比（WHtR）、体表面积、脂肪量（通过生物电阻抗分析测定）、去脂体重（FFM）、体脂百分比以及超重/肥胖情况。
舒张压和收缩压（分别考虑）的最佳拟合模型包括去脂体重、心率，收缩压的最佳拟合模型还包括身高。高正常血压/高血压（H-N/EBP）的最佳拟合模型仅包含腰高比，与其他变量无独立关联。腰高比在0.5至0.7之间时，H-N/EBP的患病率增至原来的三倍。
在现有变量中，易于获取和计算的腰高比是血压升高的最强相关因素，是高血压发生预测因素纵向研究的主要候选指标。
ClinicalTrials.gov标识符，NCT00746083。
