A treatise on blood pressure in ocular work, with special reference to factors of interest to refractionists,

Frontispiece accompanied by guard sheet with descriptive letterpress.

Status of - high blood pressure control programs in Illinois.

Title from cover.

Blood pressure;

Mode of access: Internet.

High blood pressure control : information and education strategies for messages to public and patient audiences.

Cover title.

Catalog of consumer and professional education materials on high blood pressure /

Cover title.

National high blood pressure 12-month kit.

"May 1988."

Electrical methods of blood-pressure recording.

Mode of access: Internet.

Cosegregation analysis of natriuretic peptide genes and blood pressure in the spontaneously hypertensive rat

1. The natriuretic peptide precursor A (Nppa) and B (Nppb) genes are candidate genes for hypertension and cardiac hypertrophy in the spontaneously hypertensive rat (SHR). The purpose of the present study was to determine the role of the Nppa and Nppb genes in the development of hypertension in the SHR. 2. A cohort (n = 162) of F2 segregating intercross animals was established between strains of hypertensive SHR and normotensive Wistar-Kyoto rats. Blood pressure and heart weight were measured in each rat at 12-16 weeks of age. Rats were genotyped using 11 informative microsatellite markers, distributed in the vicinity of the Nppa marker on rat chromosome 5 including an Nppb marker. The phenotype values were compared with genotype using the computer package MAP-MAKER 3.0 (Whitehead Institute, Boston, MA, USA) to determine whether there was a link between the genetic variants of the natriuretic peptide family and blood pressure or cardiac hypertrophy. 3. A strong correlation was observed between the Nppa marker and blood pressure. A quantitative trait locus (QTL) for blood pressure on chromosome 5 was identified between the Nppa locus and the D5Mgh15 marker, less than 2 cM from the Nppa locus. The linkage score for the blood pressure QTL on chromosome 5 was 3.8 and the QTL accounted for 43% of the total variance of systolic blood pressure, 54% of diastolic blood pressure and 59% of mean blood pressure. No association was found between the Nppb gene and blood pressure. This is the first report of linkage between the Nppa marker and blood pressure in the rat. There was no correlation between the Nppa or Nppb genes or other markers in this region and either heart weight or left ventricular weight in F2 rats. 4. These findings suggest the existence of a blood pressure-dependent Nppa marker variant or a gene close to Nppa predisposing to spontaneous hypertension in the rat. It provides a strong foundation for further detailed genetic studies in congenic strains, which may help to narrow down the location of this gene and lead to positional cloning.

Kidney volume, blood pressure, and albuminuria: Findings in an Australian Aboriginal community

Background. Australian Aborigines are experiencing epidemic proportions of renal disease, marked by albuminuria and, variably, hematuria. They also have high rates of low birth weight, which have been associated with lower kidney volumes and higher blood pressures. The authors evaluated relationships between kidney volume, blood pressure, albuminuria, and hematuria in 1 homogeneous group. Methods Forty-three percent (672 of 1,560) of the population in a remote coastal Australian Aboriginal community aged 4.4 to 72.1 years participated in the study. Results: Kidney size correlated closely with body size. Systolic blood pressure (SBP) was correlated inversely with kidney length and kidney volume, after adjusting for age, sex, and body surface area (BSA); a 1-cm increase in mean kidney length was associated with a 2.2-mm Hg decrease in SBP, and a 10-mL increase in mean kidney volume was associated with a 0.6-mm Hg decrease in SBP (P = 0.001). Mean kidney volume explained 10% of the variance in SBP in a multivariate model containing age, sex, and BSA. In addition to higher SBP, adults who had the lowest quartiles of kidney volume also had the highest levels of overt albuminuria (P = 0.044). Conclusion: Smaller kidneys predispose to higher blood pressures and albuminuria in this population. The lower volumes possibly represent kidneys with reduced nephron numbers, which might be related to an adverse intrauterine environment. Susceptibility to renal disease could be a direct consequence of reduced nephron numbers; the higher blood pressures with which they are associated could also contribute to, as well as derive from, this association.

Population effects on individual systolic blood pressure: A multilevel analysis of the World Health Organization MONICA project

Individuals from the same population share a number of contextual circumstances that may condition a common level of blood pressure over and above individual characteristics. Understanding this population effect is relevant for both etiologic research and prevention strategies. Using multilevel regression analyses, the authors quantified the extent to which individual differences in systolic blood pressure (SBP) could be attributed to the population level. They also investigated possible cross-level interactions between the population in which a person lived and pharmacological (antihypertensive medication) and nonpharmacological (body mass index) effects on individual SBP. They analyzed data on 23,796 men and 24,986 women aged 35-64 years from 39 worldwide Monitoring of Trends and Determinants in Cardiovascular Disease (MONICA) study populations participating in the final survey of this World Health Organization project (1989-1997). SBP was positively associated with low educational achievement, high body mass index, and use of antihypertensive medication and, for women, was negatively associated with smoking. About 7-8% of all SBP differences between subjects were attributed to the population level. However, this population effect was particularly strong (i.e., 20%) in antihypertensive medication users and overweight women. This empirical evidence of a population effect on individual SBP emphasizes the importance of developing population-wide strategies to reduce individual risk of hypertension.

Left ventricular mass in patients with type 2 diabetes is independently associated with central but not peripheral pulse pressure

An increase in left ventricular mass (LVM) occurs in the presence of type 2 diabetes, apparently independent of hypertension (1), but the determinants of this process are unknown. Brachial blood pressure is not representative of that at the ascending aorta (2) because the pressure wave is amplified from central to peripheral arteries. Central blood pressure is probably more clinically important since local pulsatile pressure determines adverse arterial and myocardial remodeling (3,4). Thus, an inaccurate assessment of the contribution of arterial blood pressure to LVM may occur if only brachial blood pressure is taken into consideration. In this study we sought the contribution of central blood pressure (and other interactive factors known to affect wave reflection, e.g., glycemic control and total arterial compliance) to LVM in patients with type 2 diabetes.

Who's really hypertensive? - Quality control issues in the assessment of blood pressure for randomized trials

The characterization of blood pressure in treatment trials assessing the benefits of blood pressure lowering regimens is a critical factor for the appropriate interpretation of study results. With numerous operators involved in the measurement of blood pressure in many thousands of patients being screened for entry into clinical trials, it is essential that operators follow pre-defined measurement protocols involving multiple measurements and standardized techniques. Blood pressure measurement protocols have been developed by international societies and emphasize the importance of appropriate choice of cuff size, identification of Korotkoff sounds, and digit preference. Training of operators and auditing of blood pressure measurement may assist in reducing the operator-related errors in measurement. This paper describes the quality control activities adopted for the screening stage of the 2nd Australian National Blood Pressure Study (ANBP2). ANBP2 is cardiovascular outcome trial of the treatment of hypertension in the elderly that was conducted entirely in general practices in Australia. A total of 54 288 subjects were screened; 3688 previously untreated subjects were identified as having blood pressure >140/90 mmHg at the initial screening visit, 898 (24%) were not eligible for study entry after two further visits due to the elevated reading not being sustained. For both systolic and diastolic blood pressure recording, observed digit preference fell within 7 percentage points of the expected frequency. Protocol adherence, in terms of the required minimum blood pressure difference between the last two successive recordings, was 99.8%. These data suggest that adherence to blood pressure recording protocols and elimination of digit preferences can be achieved through appropriate training programs and quality control activities in large multi-centre community-based trials in general practice. Repeated blood pressure measurement prior to initial diagnosis and study entry is essential to appropriately characterize hypertension in these elderly patients.

Smoking and elevated blood pressure are the most important risk factors for subarachnoid hemorrhage in the Asia-Pacific region - An overview of 26 cohorts involving 306,620 participants

Background and Purpose - The cause of subarachnoid hemorrhage ( SAH) is poorly understood and there are few large cohort studies of risk factors for SAH. We investigated the risk of SAH mortality and morbidity associated with common cardiovascular risk factors in the Asia-Pacific region and examined whether the strengths of these associations were different in Asian and Australasian ( predominantly white) populations. Methods - Cohort studies were identified from Internet electronic databases, searches of proceedings of meetings, and personal communication. Hazard ratios (HRs) for systolic blood pressure (SBP), current smoking, total serum cholesterol, body mass index (BMI), and alcohol drinking were calculated from Cox models that were stratified by sex and cohort and adjusted for age at risk. Results - Individual participant data from 26 prospective cohort studies ( total number of participants 306 620) that reported incident cases of SAH ( fatal and/or nonfatal) were available for analysis. During the median follow-up period of 8.2 years, a total of 236 incident cases of SAH were observed. Current smoking (HR, 2.4; 95% CI, 1.8 to 3.4) and SBP > 140 mm Hg ( HR, 2.0; 95% CI, 1.5 to 2.7) were significant and independent risk factors for SAH. Attributable risks of SAH associated with current smoking and elevated SBP ( similar to 140 mm Hg) were 29% and 19%, respectively. There were no significant associations between the risk of SAH and cholesterol, BMI, or drinking alcohol. The strength of the associations of the common cardiovascular risk factors with the risk of SAH did not differ much between Asian and Australasian regions. Conclusions - Cigarette smoking and SBP are the most important risk factors for SAH in the Asia-Pacific region.

Effect of body mass index changes between ages 5 and 14 on blood pressure at age 14 - Findings from a birth cohort study

Weight reduction in clinical populations of severely obese children has been shown to have beneficial effects on blood pressure, but little is known about the effect of weight gain among children in the general population. This study compares the mean blood pressure at 14 years of age with the change in overweight status between ages 5 and 14. Information from 2794 children born in Brisbane, Australia, and who were followed up since birth and had body mass index (BMI) and blood pressure measurements at ages 5 and 14 were used. Systolic and diastolic blood pressure at age 14 was the main outcomes and different patterns of change in BMI from age 5 to 14 were the main exposure. Those who changed from being overweight at age 5 to having normal BMI at age 14 had similar mean blood pressures to those who had a normal BMI at both time points: age- and sex-adjusted mean difference in systolic blood pressure 1.54 ( - 0.38, 3.45) mm Hg and in diastolic blood pressure 0.43 ( - 0.95, 1.81) mm Hg. In contrast, those who were overweight at both ages or who had a normal BMI at age 5 and were overweight at age 14 had higher blood pressure at age 14 than those who had a normal BMI at both times. These effects were independent of a range of potential confounding factors. Our findings suggest that programs that successfully result in children changing from overweight to normal-BMI status for their age may have important beneficial effects on subsequent blood pressure.