Is the obesity epidemic reversing favorable trends in blood pressure? Evidence from cohorts born between 1890 and 1990 in the United States

BackgroundPrevious reports have described favorable changes in the relationship between systolic blood pressure and age in recent birth cohorts. The obesity epidemic might threaten that pattern.ObjectivesTo update analyses of differences between birth cohorts in the relationship between systolic blood pressure and age and to determine whether increases in obesity have had adverse effects.MethodsWe examined the systolic blood pressure distributions across birth cohorts born between 1890 and 1990 in 68,070 participants, aged 18–74 years, in the National Health (and Nutrition) Examination Surveys between 1960 and 2008. We postulated that age-adjusted 10th, 25th, 50th, 75th, and 90th percentiles of systolic blood pressure had decreased in more recent versus earlier cohorts, and that this pattern had slowed or reversed recently due, at least in part, to obesity.ResultsAfter adjusting for gender, race, age and age², the 10th, 25th, 50th, 75th, and 90th percentiles of systolic blood pressure were 1.1, 1.4, 1.9, 2.5, and 3.4 mmHg lower for each decade more recently born (all P < .0001). Quadratic terms for birth cohort were positive and significant (P < .001) across all percentiles, consistent with a decelerating cohort effect. Mediation of this deceleration was observed for body mass index ranging from 20.4% to 44.3% (P < .01 at all percentiles).ConclusionsMore recent cohorts born in the United States between 1890 and 1990 have had smaller increases in systolic blood pressure with aging. At any age, their systolic blood pressure distributions are shifted lower relative to earlier cohorts. Decreases of 1.9 mmHg in the median systolic blood pressure per decade translates into 11.4–13.3 mmHg over 6–7 decades, a shift that would contribute importantly to lower rates of cardiovascular diseases. These favorable changes are slowing, perhaps owing, at least in part, to the obesity epidemic.     

Blood Pressure at Age 3–24 Years in a Rural Community in Anhui, China

PURPOSE: This community-based study in Anhui, China examined the sex-specific pattern of blood pressure (BP) and its major determinants between age 3 and 24 years.

METHODS: BP, height, weight, and related covariates were obtained from all eligible subjects by consistent methods. A generalized additive model was used to explore independent relations between BP and covariates. The sample for analyses included a total of 14,277 subjects (7244 males and 7033 females).

RESULTS: Systolic blood pressure (SBP)increased linearly with age to an apparent plateau around the age of 15 years in girls and 20 years in boys. Diastolic blood pressure (DBP) essentially paralleled SBP. Until the age of 10, both SBP and DBP were similar in boys and girls; thereafter, values for boys surpassed those for girls with an average difference of 9 mmHg and 4 mmHg for SBP and DBP, respectively, at 20 years of age. This sex difference appeared to persist into early adulthood. The independent relation between BP and each of the three major determinants (age, height, and weight) was nonlinear over the age range studied. Sex-specific regression models with linear terms for age, height and weight were developed for each of four age groups (3–9, 10–14, 15–19, 20–24 years). The 5th, 10th, 90th, and 95th percentiles based on the percentage of predicted values can serve as the cutoffs for low, normal-low, normal-high, and high BP. The predicted values were derived from the above regression models that take into account an individual’s sex, age, height, and weight.

CONCLUSIONS: This analysis provided important basis for classification of hypertension status and subsequent investigation of environmental risk factors in this population.     

Relationship of blood pressure to cardiovascular death: the effects of pulse pressure in the elderly

PURPOSE: To investigate the relationship of systolic and diastolic blood pressure to fatal myocardial infarction, fatal stroke and other death related to cardiovascular diseases (CVD). METHODS: The study was based on a prospective longitudinal study conducted by the Veterans Administration at the Boston Outpatient Clinic. Participants are male volunteers from the greater Boston area. Main outcome measures are fatal myocardial infarction, fatal stroke and other deaths related to cardiovascular diseases. The method of pooled logistic regression was used for statistical analysis. RESULTS: For younger men (age 21-59), after adjusting for effects of other risk factors, when systolic and diastolic blood pressure were considered separately, SBP was predictive of cardiovascular death (SBP: RR = 1.23; 95% CI = (1.05, 1.45) per 10 mmHg of increase), and DBP showed a nonsignificant positive trend in relation to cardiovascular death (DBP: RR = 1.27; 95% CI = (0.95, 1.69) per 10 mmHg of increase). For older men (age 60-85), when SBP and DBP were considered separately, SBP (RR = 1.26; 95% CI = (1.02, 1.55) per 15 mmHg of increase) was directly related, but DBP (RR = 1.05; 95% CI = (0.83, 1.32) per 8 mmHg of increase) was not related to cardiovascular death. However, for the elderly group, when SBP and DBP were considered jointly in the regression model, then the regression coefficient of DBP (beta = -0.018, p = 0.30) was of approximately the same absolute magnitude as that of SBP (beta = 0.021, p = 0.02) but opposite in sign. For younger men, when SBP and DBP were considered jointly, SBP (beta = 0.021, p = 0.049) but not DBP (beta = -0.001, p = 0.953) was positively related to cardiovascular death. CONCLUSIONS: We found that, for the elderly, pulse pressure (SBP-DBP) may be a more accurate predictor of cardiovascular death than either SBP or DBP alone. The relative risk per 35 mmHg of increase of pulse pressure, which equals the approximate interval from the 10th to the 90th percentile in the elderly group, is 2.1 with 95% CI = (1.1, 3.8). In younger subjects, SBP, but not DBP, is an independent predictor of fatal CVD.     

Validation of a method of blood pressure measurement for a study of hypertension in a black African population

Hypertension is a major public health issue in Black Africa. It is also an important factor of cardiovascular risk. To determine the prevalence of hypertension in a large population in Burkina Faso, it is more practicable to use an automatic device for the measurement of BP. Before the start of the study, we tested the reliability of an automatic technique for the measurement of BP in sitting position according to the reference technique. The manometer of reference was a manual, aneroid, and calibrated manometer. The automatic manometer was oscillometric, validated according to the protocol of the British Hypertension Society. The study was held on voluntary healthy persons, or patients hospitalized in the cardiology department of the national university hospital of Ouagadougou (high blood pressure, valvulopathy, cardiac insufficiency). BP measurement was made in a sequential way, with the manual manometer, and with the automatic manometer, by a single observer. Measurement by the manual manometer was based on the auscultation of Korotkoff's murmurs. Systolic blood pressure (SBP) corresponded to phase I, and diastolic blood pressure (DBP) to phase V. Measurement by the automatic manometer was made by reading the BP shown on the device screen. The 10.0 version of the SPSS software was used for data analysis. Statistical tests were concluded with a risk of 0.05. Confidence intervals included 95% of the subjects. The percentage comparison of hypertensive subjects observed in the population by both methods was made with a paired khi2 test. We used Pearson's correlation to quantify the relation between the measures taken using the two methods. In order to quantify the degree of agreement of the two methods, we used the intraclass correlation coefficient (ICC) for quantitative BP measurements, and Kappa's coefficient for qualitative measurements (determination of normotensive or hypertensive subjects). The study was held on 50 black African subjects, with the average age of 38.54 4.83 (18 years-77 years); 55% were male subjects. With the reference method in the sleeping position, the mean SBP and DBP values were respectively 122.60 8.52 and 70.36 5.22 mmHg. The minimal and maximal SBP observed were 80 and 240 mmHg respectively, and the DBP, 30 and 130 mmHg respectively. With the automatic method in the sitting position, the mean values SBP and DBP was 119.88+7.50 and 74.80 4.36 mmHg. SBP minimal was of 75, the maximal of 210 mmHg, and the minimal and maximal DBP was respectively 51 and 121 mmHg. Pearson's correlation coefficients for SBP and DBP between the two methods were statistically different from zero; 0.92 (p<0.001), and of 0.82 (p<0.001) respectively. The ICC was 0.91 for SBP and 0.78 for DBP. Kappa's coefficient was calculated to estimate agreement for the determination of normotensive or hypertensive subjects; among the 50 subjects, 36 were classified normotensive by the two methods, and eight, hypertensive. The differences of classification concerned five hypertensive subjects and one normotensive subject, according to the referenced method. Kappa's coefficient was 0.65. The distribution of the subjects in hypertensive and normotensive did not differ significantly in the two methods (p=0.22). The agreement between the two methods was found very good for the measurement of SBP and DBP; it was good for the determination of an hypertensive or normotensive subject. It is important to test the reliability of a technique of BP measurement before the evaluation of hypertension prevalence in a large population. The reliability of the technique ensures a good estimation of the disease prevalence. It is also important to use statistically adapted tests, to avoid any wrong conclusion as to the reliability of the technique.     

Alcohol consumption, %CDT, GGT and blood pressure change during alcohol treatment

AIMS: Blood pressure (BP) changes in alcohol-dependent individuals during a 12-week alcohol relapse prevention study were examined in light of drinking status and biomarkers of alcohol consumption [carbohydrate-deficient transferrin (%CDT) and gamma-glutamyl transpeptidase (GGT)]. METHODS: Of 160 randomized alcoholic individuals, 120 who had hypertension and in whom daily drinking data was available, at 6 and 12 weeks of treatment were included. The impact of alcohol consumption on change in systolic BP (SBP) and diastolic BP (DBP) was examined. Further analysis determined the relationship between BP and alcohol-use biomarkers. RESULTS: A significant effect of complete abstinence on both SBP (-10 mmHg; P = 0.003) and DBP (-7 mmHg; P = 0.001) when compared to any drinking (SBP and DBP = -1 mmHg) was observed. At week 12, participants with a positive %CDT (> or =2.6) had 7 mmHg greater SBP (P = 0.01) and DBP (P < 0.001) than those with negative %CDT. Participants with positive GGT (> or =50 IU) had 10 mmHg greater SBP (P = 0.12) and 9 mmHg greater DBP (P = 0.03) than those with negative GGT. The percent change in SBP was correlated with percent change in %CDT (P = 0.003) but not GGT (P = ns). The percent change in DBP was correlated with both percent change in %CDT (P < 0.0001) and GGT (P = 0.03). CONCLUSIONS: Abstinence from alcohol significantly decreased the BP and a positive relationship between BP and both alcohol-use biomarkers was illustrated. Since %CDT is more specific than GGT for heavy alcohol consumption, clinicians may monitor the role of alcohol in hypertension using %CDT as a supplemental aid, providing an objective assessment of drinking to influence BP treatment decisions.     

1994–1996 U.S. Singleton Birth Weight Percentiles for Gestational Age by Race,Hispanic Origin,and Gender

Objectives: Establishing and comparing race, ethnic, and gender-specific birth weight percentiles for gestational age is requisite for investigating the determinants of variations in fetal growth. In this study, we calculate percentiles of birth weight for gestational age for the total 1994–1996 U.S. population and contrast these percentiles by racial/ethnic and gender groups. Methods: Single live births to U.S. resident mothers were selected from the 1994–1996 U.S. Natality Files. After exclusions, 5,973,440 non-Hispanic Whites, 1,393,908 non-Hispanic African Americans, 1,683,333 Hispanics, 80,187 Native Americans, and 510,021 other racial/ethnic groups were used to calculate distribution percentiles of birth weight for each gestational age for which there were at least 50 cases to calculate the 50th percentile and 100 cases to calculate the 10th percentile. Results: Fetal growth patterns among the four U.S. racial/ethnic groups varied markedly and, across the gestational age range, there was considerable oscillation in the relative ranking of any one group's birth weight percentile value in comparison to the others. Males had relatively higher birth weight percentile values than females. The proportion of infants with a birth weight value less than 1994–1996 U.S. population's 10th percentile value of birth weight for their corresponding gestational age was 7.87 for non-Hispanic Whites, 15.43 for non-Hispanic African Americans, 9.30 for Hispanics, and 8.81 for Native Americans. Conclusions: While the factors underlying trends and population subgroup differences in fetal growth are unclear, nutrition, smoking habits, health status, and maternal morbidity are possible precursors for part of the variations in patterns of fetal growth. As prenatal care has been touted as a means to reduce the risk of fetal growth restriction at term, assuring the availability and accessibility of comprehensive prenatal care services is viewed as an essential corollary in the effort to improve fetal growth patterns in the United States.     

儿童期血压偏高对成年期高血压的影响研究

目的 本研究旨在探讨儿童期血压偏高对成年期高血压的影响,为成人高血压的早期防控提供科学依据。方法 基于“中国居民健康与营养调查”资料(1991-2011年),纳入儿童期(6~17岁)和成年期(18~38岁)均进行至少1次随访的研究对象。儿童期血压偏高前期定义采用中国儿童青少年血压参考值性别和年龄的第90百分位(P₉₀)至第95百分位(P₉₅),儿童期血压偏高采用≥P₉₅。成年期高血压前期为收缩压/舒张压≥120/80 mmHg且<140/90 mmHg;成年期高血压为收缩压/舒张压≥140/90 mmHg,或有高血压史,或目前正服用降压药物。采用协方差分析和Cox比例风险回归模型分析儿童期血压偏高对成年期高血压前期和高血压的影响,控制混杂因素包括儿童期性别和年龄,成年期的体重指数(BMI)、吸烟和饮酒。结果 本研究共纳入1 984名数据完整的研究对象,中位随访时间为11.7年。基线儿童期共有108人(5.4%)为血压偏高前期,199人(10.0%)为血压偏高。随访成年期共有697人(35.1%)为高血压前期,104人(5.2%)为高血压。协方差分析表明,成年期收缩压和舒张压水平均随着儿童期血压百分位的增加而增加(P_趋势<0.001)。多因素Cox回归分析显示,儿童期血压偏高者成年后为高血压前期的风险增加(HR=1.41,95%CI:1.12~1.77)。儿童期血压偏高者成年后为高血压的风险显著增加(HR=1.73,95%CI:1.01~2.98)。结论 儿童期血压偏高会增加成年期罹患高血压的风险。应该重视儿童青少年血压监测,对血压偏高的高危儿童应及时采取干预措施。     

山东省青少年体质量指数与血压关系分析

目的分析群体儿童少年体质量指数(BM I)百分位数分布与血压水平的关系,为高血压病的早期预防提供依据。方法依据2005年山东省学生体质健康调研资料,将个体的收缩压(SBP)和舒张压(DBP)转化为Z分,用标准离差法分析7～18岁青少年BM I百分位数分布与血压水平的关联性。结果青少年收缩压随BM I百分位数的递增而上升,收缩压Z分由BM I相似文献   

Interrelations among smoking habits, casual blood pressure and intraocular pressure in middle and old-aged Japanese residents

Objectives To investigate the association of smoking habits with blood pressure (BP) and intraocular pressure (IOP), and to examine whether the smoking-BP association is related to the IOP level. Methods This study was conducted on the basis of a cross-sectional design using annual health check-up data during one-year between August, 1999 and August, 2000 for 611 middle and old-aged Japanese residents living in Ibaraki prefecture, Japan. Results After adjustment for age, gender, body mass index and alcohol intake score, the proportion of hypertensives, and the mean systolic and diastolic blood pressure (SBP and DBP) of the subjects without antihypertensive medications were the highest (50.4%, 129.6 mmHg and 75.9 mmHg, respectively) in the “smokers of 25 or more cigarettes per day with intraocular pressure (IOP)≥15 mmHg” of six subgroups crossed by three smoking categories (non-smokers, 1 to 24 cigarettes per day, and 25 or more cigarettes per day) and two IOP categories (less than 15 mmHg, and 15mmHg or greater). On the other hand, the adjusted proportion of hypertensives, and the adjusted mean SBP and DBP decreased with increasing smoking category in the individuals with less than 15 mmHg of the IOP (p for trend=0.028 for proportion of hypertensives 0.008 for the SBP, and 0.001 for the DBP, respectively). Conclusions Heavy smoking may be specifically related to ‘high BP accompanied by high IOP’, although the BP may be inversely associated with smoking under the condition without high IOP.     

Assessing cardiovascular reactivity in working women with the social competence interview

The Social Competence Interview (SCI), an interview to induce cardiovascular reactivity through recounting a stressful life experience, was used with a sample of 120 working women employed as childcare providers. Women recounted their most stressful work factor while cardiovascular reactions were monitored at 2-minute intervals (data points included 4 baseline, 6 SCI, and 3 recovery). Increases were found when comparing mean baseline and SCI measures: systolic blood pressure (SBP) increased 10.00 mmHg; diastolic blood pressure (DBP)increased 10.63 mmHg; and heart rate increased 4.57 beats per minute. Consistent with the literature SBP and DBP were higher for some subgroups of women (those who were 50 years or older, were obese, or had 4 or more risk factors) across all data points. There were no time by individual difference interactions, indicating that the patterns of change over time were the same across groups. In a logistic regression, comparing women who reached SBP > or = 140 mmHg and/or DBP > or = 90 mmHg during the SCI versus those who did not, higher BP was associated with being older and obese, having a higher level of acceptance coping, and a lower level of suppression of competing activities coping.     

Blood and Urine Cadmium,Blood Pressure,and Hypertension: A Systematic Review and Meta-analysis

Background

Cadmium exposure has been inconsistently related to blood pressure.

Objectives

We updated and reevaluated the evidence regarding the relationships of blood cadmium (BCd) and urine cadmium (UCd) with blood pressure (BP) and hypertension (HTN) in nonoccupationally exposed populations.

Data sources and extraction

We searched PubMed and Web of Science for articles on BCd or UCd and BP or HTN in nonoccupationally exposed populations and extracted information from studies that provided sufficient data on population, smoking status, exposure, outcomes, and design.

Data synthesis

Twelve articles met inclusion criteria: eight provided data adequate for comparison, and five reported enough data for meta-analysis. Individual studies reported significant positive associations between BCd and systolic BP (SBP) among nonsmoking women [β = 3.14 mmHg per 1 μg/L untransformed BCd; 95% confidence interval (CI), 0.14–6.14] and among premenopausal women (β = 4.83 mmHg per 1 nmol/L log-transformed BCd; 95% CI, 0.17–9.49), and between BCd and diastolic BP (DBP) among women (β = 1.78 mmHg comparing BCd in the 90th and 10th percentiles; 95% CI, 0.64–2.92) and among premenopausal women (β = 3.84 mmHg per 1 nmol/L log-transformed BCd; 95% CI, 0.86–6.82). Three meta-analyses, each of three studies, showed positive associations between BCd and SBP (p = 0.006) and DBP (p < 0.001) among women, with minimal heterogeneity (I² = 3%), and a significant inverse association between UCd and HTN among men and women, with substantial heterogeneity (I² = 80%).

Conclusion

Our results suggest a positive association between BCd and BP among women; the results, however, are inconclusive because of the limited number of representative population-based studies of never-smokers. Associations between UCd and HTN suggest inverse relationships, but inconsistent outcome definitions limit interpretation. We believe a longitudinal study is merited.     

National standards of blood pressure for children and adolescents in Spain: international comparisons. The Spanish Group for the Study of Cardiovascular Risk Factors in Childhood and Youth.

This study determined age-specific patterns of blood pressure (BP) in Spanish children aged 1-18 years for the purpose of developing BP guidelines for this population. Age- and sex-specific BP levels were constructed by pooling data from 15 studies conducted in Spain. Pooled mean BP levels were then compared with those reported by the US Second Task Force on Blood Pressure Control in Children and those recently reported from a separate pooled analysis of the relevant published surveys collected worldwide. In the Spanish data, the average 1-year age increment in Systolic BP (SBP) was uniform for boys and girls until 13 years at 2 mmHg; for boys aged 13-18 the increase was 1.3 mmHg/year; in contrast, girls reached their maximum values at age 13 and the means remained basically unchanged for female adolescents. Fifth-phase diastolic BP (DBP5) values showed a uniform increase for both boys and girls from ages 6 to 18 years at 0.9 mmHg/year. In most age-sex subgroups, mean SBP values were higher (7-8 mmHg on average) in Spain than in the US. However, Spanish values for SBP were in general only slightly higher or approximately equal to those for the international data, from ages 6 to 18 years. The patterns of change in SBP with age differed somewhat in the three data sets. Comparisons for DBP were limited to the age groups for which readings of DBP5 were available. For DBP5, only slight differences between the Spanish and International pools were observed (ages 6-18 compared), but these values were notably higher than those from the US (ages 13-18 compared). These findings suggest that the use of any particular age-based standard to evaluate readings in children in diverse populations cannot be recommended, at least until there is a better understanding of the true differences in BP between populations.     

Need to prevent and control high-normal and high blood pressure, particularly so-called "mild" hypertension: epidemiological and clinical data

The need to prevent and control high blood pressure (HBP), including so-called "mild" hypertension [diastolic blood pressure (DBP) 90-104 mm Hg in adults age 30+] stems from the extensive data on the increased risks due to these common blood pressure (BP) levels, including risk of catastrophic cardiovascular events (coronary, cerebrovascular, etc.), both nonfatal and fatal. Prospective population data from the national cooperative Pooling Project and the Chicago Heart Association Detection Project in Industry illustrate the extensively documented facts. They also show that only a small minority of middle-aged and older Americans have optimal low-normal BP levels, i.e., DBP less than 80 mm Hg (SBP less than 120). Thus, the problem of BP above optimal level for health over a long life span is a population-wide problem. The data also show that the great majority of excess catastrophic events attributable to elevated BP occur among people with DBP 90-104 and 80-89 mm Hg, levels very common in the population. Most people with such BP levels also have one or more other major risk factors (e.g., hypercholesterolemia, cigarette use, ECG abnormalities) and thus are at markedly increased risk, both relative and absolute. In addition to these excess risks for major illness, disability, and death, people with BP above optimal levels are more highly prone to other events, clinical and subclinical, that have adverse effects on long-term prognosis, including development of target organ damage and severe hypertension. These data lead to the following inferences about medical care and public health strategy: (a) A key task is, by safe nutritional-hygienic means, to shift the entire population distribution of BP downward, for both primary and secondary prevention of HBP. Such means include prevention and control of obesity, high sodium and alcohol intake, and sedentary habit, from early childhood on. (b) People with DBP 80-89 mm Hg need to be identified promptly, with institution of nutritional-hygienic measures to prevent development of frank hypertension and to correct other risk factors. (c) People with DBP 90-104 and higher need to be identified promptly, with institution of measures to normalize BP and control other major risk factors, by nutritional-hygienic means alone whenever possible or in combination with drug treatment for HBP when necessary to prevent organ system damage, serious illness, disability, and premature death.(ABSTRACT TRUNCATED AT 400 WORDS)     

Randomized Trial on the Effects of Dietary Potassium on Blood Pressure and Serum Potassium Levels in Adults with Chronic Kidney Disease

In the general population, an increased potassium (K) intake lowers blood pressure (BP). The effects of K have not been well-studied in individuals with chronic kidney disease (CKD). This randomized feeding trial with a 2-period crossover design compared the effects of diets containing 100 and 40 mmol K/day on BP in 29 adults with stage 3 CKD and treated or untreated systolic BP (SBP) 120–159 mmHg and diastolic BP (DBP) <100 mmHg. The primary outcome was 24 h ambulatory systolic BP. The higher-versus lower-K diet had no significant effect on 24 h SBP (−2.12 mm Hg; p = 0.16) and DBP (−0.70 mm Hg; p = 0.44). Corresponding differences in clinic BP were −4.21 mm Hg for SBP (p = 0.054) and −0.08 mm Hg for DBP (p = 0.94). On the higher-K diet, mean serum K increased by 0.21 mmol/L (p = 0.003) compared to the lower-K diet; two participants had confirmed hyperkalemia (serum K ≥ 5.5 mmol/L). In conclusion, a higher dietary intake of K did not lower 24 h SBP, while clinic SBP reduction was of borderline statistical significance. Additional trials are warranted to understand the health effects of increased K intake in individuals with CKD.     

The Significance of Duration and Amount of Sodium Reduction Intervention in Normotensive and Hypertensive Individuals: A Meta-Analysis

The purpose of this meta-analysis was to establish the time for achievement of maximal blood pressure (BP) efficacy of a sodium reduction (SR) intervention and the relation between the amount of SR and the BP response in individuals with hypertension and normal BP. Relevant studies were retrieved from a pool of 167 randomized controlled trials (RCTs) published in the period 1973–2010 and integrated in meta-analyses. Fifteen relevant RCTs were included in the maximal efficacy analysis. After initiation of sodium reduction (range: 55–118 mmol/d), there were no significant differences in systolic blood pressure (SBP) or diastolic blood pressure (DBP) between measurements at weeks 1 and 2 (∆SBP: −0.18 mmHg/∆DBP: 0.12 mmHg), weeks 1 and 4 (∆SBP: −0.50 mmHg/∆DBP: 0.35 mmHg), weeks 2 and 4 (∆SBP: −0.20 mmHg/∆DBP: −0.10 mmHg), weeks 2 and 6 (∆SBP: −0.50 mmHg/∆DBP: −0.42 mmHg), and weeks 4 and 6 (∆SBP: 0.39 mmHg/∆DBP: −0.22 mmHg). Eight relevant RCTs were included in the dose-response analysis, which showed that within the established usual range of sodium intake [<248 mmol/d (5700 mg/d)], there was no relation between the amount of SR (range: 136–188 mmol) and BP outcome in normotensive populations [∆SBP: 0.99 mm Hg (95% CI: 2.12, 4.10), P = 0.53; ∆DBP: −0.49 mm Hg (95% CI: −4.0, 3.03), P = 0.79]. In contrast, prehypertensive and hypertensive populations showed a significant dose-response relation (range of sodium reduction: 77–140 mmol/d) [∆SBP: 6.87 mmHg (95% CI: 5.61, 8.12, P < 0.00001); ∆DBP: 3.61 mmHg (95% CI: 2.83, 4.39, P < 0.00001)]. Consequently, the importance of kinetic and dynamic properties of sodium reduction, as well as baseline BP, should probably be considered when establishing a policy of sodium reduction.     

Low job control is associated with higher diastolic blood pressure in men with mildly elevated blood pressure: the Rosai Karoshi study

Job strain is a risk factor for hypertension, but it is not fully understood if components of job strain, or job demand or job control per se could be related to blood pressure (BP), and if so, whether the relationship differs between normotension and mildly elevated BP. We examined resting BP, and job stress components in 113 Japanese male hospital clerks (38.1 ± 4.4 yr). Subjects were classified into normotensive (NT) (<130/85 mmHg, n=83) and mildly elevated BP (ME) (≥130/85 mmHg) groups. Diastolic BP (DBP) showed a significant interaction between group and job control level (p=0.013). Subjects with low job control demonstrated higher DBP than those with high job control (89.1 ± 2.1 vs. 82.3 ± 2.3 mmHg, p=0.042) in ME group even after adjustments for covariates while DBP did not differ between low and high job control subjects in NT group. Systolic BP (SBP) did not differ between high and low job control subjects in both groups. Neither SBP nor DBP differed between high and low demand groups in either group. Among job strain components, job control may be independently related to BP in Japanese male workers with mildly elevated BP.     

Relation of vegetable, fruit, and meat intake to 7-year blood pressure change in middle-aged men: the Chicago Western Electric Study

Information is sparse on the role of foods in long-term blood pressure (BP) change. The investigators examined relations of food intake to BP change in a prospective cohort study of 1,710 employed men in Chicago, Illinois, initially aged 41-57 years. In 1958 and 1959, BP was measured and nutrient intake assessed by comprehensive interview. In 1959, intake of 26 specific food groups was also assessed. BP was remeasured annually through 1966. The generalized estimating equation method was used to analyze relations of food group intakes to average annual BP change, adjusting for age, weight at each year, alcohol consumption, calories, and other foods. Average systolic blood pressure (SBP)/diastolic blood pressure (DBP) increase was 1.9/0.3 mmHg per year. The SBP of men who consumed 14-42 cups of vegetables a month (0.5-1.5 cups/day) versus <14 cups a month (<0.5 cups/day) was estimated to rise 2.8 mmHg less in 7 years (p < 0.01). The SBP of men who consumed 14-42 cups of fruit a month versus <14 cups a month was estimated to increase 2.2 mmHg less in 7 years (p < 0.05). Beef-veal-lamb and poultry intakes were related directly to a greater SBP/DBP increase (p < 0.05). These results support the concept that diets higher in fruits and vegetables and lower in meats (except fish) may reduce the risk of developing high BP.     

Modelling the association of blood pressure during pregnancy with gestational age and body mass index

Improved understanding of the determinants of blood pressure (BP) changes during pregnancy is essential for decreasing the morbidity and mortality borne by women and their families worldwide. While most epidemiological studies consider associations based on categorical risk factor classifications, using measurements on a continuous scale has been advocated as a means of gaining richer insights into biological processes. We modelled the relationship during pregnancy of continuous systolic (S) and diastolic (D) BP distributions with gestational age and pre-pregnancy body mass index (BMI) using fractional polynomials. We used information, including antenatal BP values abstracted from medical records, from a prospective cohort of 1733 women recruited before 20 weeks' gestation.
The percentiles for SBP and DBP changed over pregnancy, with DBP percentiles decreasing initially, followed by an increase starting about mid-second trimester. Modelling the joint impact of BMI and gestational age on mean BP indicated an increase in mean BP with increasing BMI that was attenuated at higher BMI levels, later in pregnancy. This attenuation persisted in a variety of sub-analyses which explored the possibility that it was caused by confounding or by influential groupings of subjects. Estimated longitudinal percentiles that characterise the BP distribution across gestation may facilitate evaluation of BP during pregnancy. BP patterns observed over pregnancy and, in particular, the attenuation of BP increases at high BMI, late in pregnancy, can provide insights towards elucidating the mechanisms that drive BP changes during pregnancy.     

Trimester-specific blood pressure levels in relation to maternal pre-pregnancy body mass index

We evaluated the influence of maternal pre-pregnancy body mass index (BMI), based on reported pre-pregnancy weight and height, on blood pressure (BP) levels during pregnancy by using information from a prospective cohort of 1733 women recruited before 20 weeks' gestation. Maternal antenatal BP values were abstracted from medical records, and we evaluated the mean BP differences according to BMI group in regression models, using generalised estimating equations to account for repeated BP records within each pregnancy. In each trimester, mean systolic BP (SBP) and diastolic BP (DBP) values were positively associated with maternal pre-gestational BMI. This association persisted after adjustment for maternal age, parity, smoking, education, marital status and physical activity. Overweight women (25-29 kg/m(2)) had first-, second- and third-trimester mean SBPs that were 8.1, 7.7 and 8.2 mmHg, respectively, higher than values observed in lean women (<20 kg/m(2)). Mean DBP values were 4.5, 5.4 and 5.6 mmHg higher for each successive trimester in overweight vs. lean women. Obese (>30 kg/m(2)) women consistently had the highest mean SBP and DBP values. Trimester-specific mean SBP values were 10.7-12.0 mmHg higher among obese women vs. lean women. Corresponding trimester-specific mean DBP values were 6.9-7.4 mmHg higher in obese vs. lean women. Similar patterns were observed when trimester-specific average mean arterial pressures were evaluated. Elevated pregnancy BPs associated with maternal pre-gestational BMI are consistent with a large body of literature that documents increased pre-eclampsia risk among overweight and obese women.     

Association of dietary sodium intake and blood pressure in the German population

Aim

The present study investigated the association of dietary sodium intake and blood pressure (BP) based on existing data from the German National Health Interview and Examination Survey (GNHIES) and the associated German Nutrition Survey (GeNuS).

Subject and methods

After exclusion of participants with known hypertension and/or anti-hypertensive medication use, complete data of the GeNuS subsample of the 1998 GNHIES were analysed for 1,539 men and 1,553 women aged 18–79?years. The survey included a health and lifestyle questionnaire, a medical examination and a comprehensive diet history interview. Sodium density (g/1,000?kcal) was examined in quartiles of systolic and diastolic BP (SBP and DBP). Multiple linear regression models were used to investigate associations of sodium density and SBP or DBP. Adjustments were made for sex, age and socio- and health-behavioral risk factors previously found to be related to BP in univariate analysis.

Results

Participants with a high SBP and DBP (fourth quartile of SBP: ≥ 142?mmHg in men; ≥ 139?mmHg in women) had a significantly higher dietary sodium intake than individuals with a lower BP. In the multiple models, both SBP and DBP were significantly associated with sodium density when adjusted for other factors such as sex, age, body mass index and alcohol consumption.

Conclusion

An association of dietary sodium intake and BP in the German population could be found. Further research using sodium data collected via 24-h urine samples is urgently needed for evidence-based public health policy reducing risk of BP associated morbidities and mortalities in Germany.