Andersen Ulla Overgaard
Dan Med J. 2017 Mar;64(3).
Strategies to reduce the burden of blood pressure attributable diseases require knowledge of secular trend in PBP and its determinants. The issues were investigated in the Copenhagen City Heart Study. The design of CCHS is a repeated measures study. Such designs are uniquely suited to studying changes of an outcome and what risk factors may be associated with that outcome. Repeated measures studies are very well suited for trend analysis by using mixed effect analyses. SBP decreased about 2 mmHg in 25 years. The risk factors age, gender and BMI were found valid as determinant factors for secular trends in SBP. In addition, the following factors were identified: household income and the interactions ''genderage'' and ''surveyage''. The interaction ''genderage'' stated that the difference between SBP in the two genders was great in the young individuals and diminished by age. The interaction ''surveyage'' stated that SBP in the young individuals decreased more with survey than SBP in the older individuals. Thus, the 20 years old subjects in survey 2, 3 and 4 have lower SBP than the 20 years old subjects in preceding surveys. The slopes were less steep in higher ages. In the group of elderly and old subjects the trend is partly explained by treatment bias because more and more subjects leave the untreated group and start treatment. The factor ''household income'' was significant only in the female population and stated that high-income women had lower SBP and a more beneficial secular trend in SBP than low-income women. Marital status, self-reported physical exercise and alcohol intake were not significant factors. A number of factors, that are interesting in relation to SBP, were not included in the CCHS and therefore not investigated. Among them are salt intake, childhood factors, genetic factors and the DASH diet. A survival study was performed to investigate the mortality rate in relation to SBP changes during the observation period. A Cox regression analysis was used in this study. The survival study demonstrated that SBP was a significant variable in survival models for all age groups. There was a decrease in mortality rate in young to middle-aged individuals. The mortality rate that is associated with a particular value of SBP did not change. Thus, it was concluded that SBP was as dangerous as it has always been and that the reduction in mortality rate was most pronounced in the age classes that also experienced the greatest reduction in blood pressure. During the observation period the number of treated individuals in the population increased from 6.5% to 18.1%. About 50% of the population was hypertensive (SBP ≥ 140 mmHg or treated with antihypertensive medication). The value of SBPtreated was used as an indicator for hypertension control in the treated population. Hypertension control is a collection of topics that includes guidelines, available medicine, physicians attitude towards hypertension treatment, systematic control, patient awareness and patient compliance. The analysis of trends in SPB in treated hypertensives showed that SBP decreased 9.2 mmHg in 25 years. The result may be ascribed to improvements in treatment but may also be caused by a change in start-to-treat practice: If hypertensives start treatment at an increasingly lower SBP then SBP will decrease without improvements in treatment. Therefore the start-to-treat practice was evaluated by SBP. A change in SBP was not observed. Thus, the 9.2 mmHg decrease in SBP may represent improvements in treatment. ''Age'' was a significant factor for SBP. This result demonstrated that elderly and old individuals were treated less successful than young and middle-aged individuals. Subjects diagnosed with ischemic heart disease constitute a group with a more advantageous slope than subjects with other diagnoses (stroke, IHD in combination with stroke, and hypertension alone). Self-reported physical exercise, gender, alcohol intake, household income and family structure were not significant as variables in the decreasing SBP among treated hypertensives. Thus, the papers in this thesis described SBP trends in the untreated and in the treated part of a population. Different patient-related factors were identified as determinant factors for trends in the two groups. The determinant factors are the explanatory variables most associated with trends in SBP. The determinant factors were different for the two groups (except for age).
减轻血压相关疾病负担的策略需要了解人群血压（PBP）的长期趋势及其决定因素。哥本哈根城市心脏研究对这些问题进行了调查。哥本哈根城市心脏研究（CCHS）的设计是一项重复测量研究。这种设计非常适合研究结果的变化以及哪些风险因素可能与该结果相关。重复测量研究非常适合通过混合效应分析进行趋势分析。收缩压（SBP）在25年中下降了约2 mmHg。风险因素年龄、性别和体重指数（BMI）被发现是SBP长期趋势的有效决定因素。此外，还确定了以下因素：家庭收入以及“性别年龄”和“调查年龄”的相互作用。“性别年龄”的相互作用表明，在年轻人中，两性之间的SBP差异很大，并且随着年龄的增长而减小。“调查年龄”的相互作用表明，年轻人的SBP随调查的下降幅度比老年人更大。因此，调查2、3和4中的20岁受试者的SBP低于之前调查中的20岁受试者。在较高年龄组中，斜率较平缓。在老年和高龄受试者组中，这种趋势部分是由治疗偏倚解释的，因为越来越多的受试者离开未治疗组并开始治疗。“家庭收入”因素仅在女性人群中具有显著性，表明高收入女性的SBP较低，且SBP的长期趋势比低收入女性更有利。婚姻状况、自我报告的体育锻炼和酒精摄入量不是显著因素。一些与SBP相关的有趣因素未纳入CCHS，因此未进行调查。其中包括盐摄入量、儿童期因素、遗传因素和得舒饮食（DASH饮食）。进行了一项生存研究以调查观察期内与SBP变化相关的死亡率。本研究使用了Cox回归分析。生存研究表明，SBP在所有年龄组的生存模型中都是一个显著变量。年轻至中年个体的死亡率有所下降。与特定SBP值相关的死亡率没有变化。因此，得出的结论是，SBP一直都同样危险，死亡率的降低在血压下降幅度最大的年龄组中最为明显。在观察期内，人群中接受治疗的个体数量从6.5%增加到18.1%。约50%的人群患有高血压（SBP≥140 mmHg或接受抗高血压药物治疗）。治疗后SBP值被用作治疗人群中高血压控制的指标。高血压控制是一个包含多个主题的集合，包括指南、可用药物、医生对高血压治疗的态度、系统控制、患者意识和患者依从性。对治疗的高血压患者的SBP趋势分析表明，SBP在25年中下降了9.2 mmHg。结果可能归因于治疗的改善，但也可能是由于开始治疗实践的变化：如果高血压患者开始治疗时的SBP越来越低，那么即使治疗没有改善，SBP也会下降。因此，通过SBP评估开始治疗实践。未观察到SBP的变化。因此，SBP下降9.2 mmHg可能代表治疗的改善。“年龄”是SBP的一个显著因素。这一结果表明，老年和高龄个体的治疗效果不如年轻和中年个体。被诊断患有缺血性心脏病的受试者组的斜率比其他诊断（中风、缺血性心脏病合并中风和单纯高血压）的受试者组更有利。自我报告的体育锻炼、性别、酒精摄入量、家庭收入和家庭结构在治疗的高血压患者SBP下降中作为变量不具有显著性。因此，本论文中的文章描述了人群中未治疗和已治疗部分的SBP趋势。不同的患者相关因素被确定为两组趋势的决定因素。决定因素是与SBP趋势最相关的解释变量。除年龄外，两组的决定因素不同。
