Isolated systolic hypertension in Dutch middle aged and all-cause mortality: a 25-year prospective study

In the early 1950s, the blood pressure of 3901 Dutch civil servants and their spouses aged 40-65 years was measured in a general health survey. Isolated systolic hypertension (systolic pressure greater than 160 mmHg, diastolic pressure less than 90 mmHg) was observed in 6.3% of the women and 3.0% of the men. The prevalence increased with age and it was more common in women in all age groups. Using logistic regression, with adjustment for potential confounders (age, smoking, serum cholesterol, Quetelet index, alcohol consumption, haemoglobin level, pulse rate and diastolic blood pressure) the association of 15- and 25-year total mortality with isolated systolic hypertension was determined. Compared to normotensive people (systolic pressure less than or equal to 135 mmHg, diastolic pressure less than 90 mmHg), the risk of death from all causes was significantly higher for men with isolated systolic hypertension after 15 and 25 years of follow-up (odds ratio OR = 2.4, 95% confidence interval (CI) 1.2-4.8 and OR = 3.2, 95% CI 1.3-8.0). For women 15-years mortality risk was strongly associated with isolated systolic hypertension (OR = 3.7, 95% CI 1.4-9.7). The increased risk was less pronounced after 25 years of follow-up (OR = 1.7, 95% CI 0.96-3.0). Our results support those of other studies and indicate that isolated systolic hypertension is an important independent risk factor for all-cause mortality. Since isolated systolic hypertension may be an indicator for the early onset of ageing, it is important to study its determinants and to pay more attention to its diagnosis and treatment in middle-aged populations.     

Occupational exposure to noise, hearing loss and arterial hypertension

Clinical examinations and audiograms were conducted in a group of 249 men working in a foundry of the Paris area. Before and after adjustment for age, systolic blood pressure levels were positively associated with the duration of the occupational exposure to a noise greater than 85 dBA: 127.8 mmHg in the non-exposed group, 128.6 mmHg when the exposure lasted less than 10 years, 130.1 mmHg from 10 to 19 years, and 140.1 mmHg over 20 years (p less than 0.001). The odds-ratio of arterial hypertension associated with an occupational exposure over 20 years was 1.6 (p less than 0.05). There was no relationship between noise-induced hearing loss and blood pressure levels. These results suggest that there may be a population at increased risk of high blood pressure. However, the causal relationship between noise exposure and high blood pressure should be confirmed.     

Dietary sodium, calcium, and potassium, and blood pressure

The cross-sectional association of systolic blood pressure with dietary sodium, calcium, and potassium, as estimated from dietary histories, was investigated by multiple regression analysis of data gathered in the Netherlands in the early 1950s in a general health examination of 2,291 middle-aged civil servants and spouses of civil servants. A statistically significant negative trend with systolic blood pressure was seen for calcium intake in both males and females, even after adjustments for covariates. For sodium and potassium intake, the observed negative trends were not significant after multivariate analyses. In addition, no consistent associations were found between diastolic blood pressure and the micronutrients after multivariate analyses, except for a significant negative association with calcium intake in females. In this study population, blood pressure was a strong independent risk factor of total mortality: 15- and 25-year mortality was about twice as high for hypertensives (greater than or equal to 160 mmHg) as for normotensives (less than 160 mmHg). These findings support the conclusion in recent epidemiologic studies that higher intakes of calcium are associated with lower systolic blood pressure, and they extend the evidence to an earlier time period.     

Isolated systolic hypertension in 14 communities

In the Hypertension Detection and Follow-up Program, 158,906 individuals from 14 communities around the United States had their blood pressure measured in their homes in 1972-1973. Of the total population screened, 2.4% had isolated systolic hypertension (systolic blood pressure greater than or equal to 160 mmHg and diastolic blood pressure less than 90 mmHg). Isolated systolic hypertension was present for 0.5% of those aged 30-39 years and 6.8% among those aged 60-69 years. The prevalence in blacks and women was greater than the prevalences in both whites and men. The prevalence among those taking antihypertensive medications at the time of screening was 6.1%, and 1.9% among those not on antihypertensive medications. From the individuals with "normal" diastolic blood pressure on the single home measurement (less than 90 mmHg), a random sample of 5,032 individuals were followed for mortality for eight years. Prevalence of isolated systolic hypertension was similar in this sample to that in the total. Among those not on antihypertensive medications, 8-year life table all-cause mortality rates adjusted for age, race, and sex were 17.6% for those with systolic blood pressure greater than or equal to 160 mmHg and 7.7% for those with systolic blood pressure greater than 160 mmHg. Among this population, all of whom had a diastolic blood pressure less than 90 mmHg, a multiple logistic analysis adjusting for baseline treatment status, age, race, sex, education, smoking, weight, pulse, physical activity, and systolic blood pressure revealed that each millimeter increase in systolic blood pressure was associated with approximately a 1% increase in mortality over the eight years of follow-up (p less than 0.05). Isolated systolic hypertension is both relatively common and a significant risk factor for subsequent mortality.     

Geographical variations in blood pressure in British men and women

Geographical variations in blood pressure have been studied using an automatic sphygmomanometer in 2596 men and women aged 25-29, 40-44 and 55-59 living in nine British towns. In males aged 40-59, systolic blood pressure showed a range in age-adjusted town means of 9.0 mmHg (p less than 0.05); in females the difference of 8.6 mmHg was not significant (p = 0.14). Mean arterial pressure (MAP) and diastolic at age 40-59 were significantly different between towns for both sexes. Differences at age 25-29 were of a similar magnitude, and the mean town blood pressures at 25-29 correlated highly with those at 40-59 [systolic; males r = 0.74 (p less than 0.05), females r = 0.65 (p = 0.059)]. The ranking of town blood pressures in an earlier study was reflected in the present study, but stronger associations were observed with cardiovascular mortality. It is concluded that geographical blood pressure variations in Britain are established by age 25-29 years.     

Blood pressure in relation to birth weight in twins and singleton controls matched for gestational age

Associations between adult blood pressure and birth weight were investigated in 122 same-sex twin pairs aged 18-50 years and 86 singleton controls matched according to maternal age and parity, gender, gestational age, and current age who were recruited via an obstetric database in Aberdeen, Scotland, in 1999. Twins weighed on average 425 g less than controls at birth (p < 0.001) but did not differ significantly in adult height or systolic or diastolic blood pressure from the controls. Among controls, the differences in systolic and diastolic blood pressure per kg of difference in birth weight, adjusted for gender, gestational age, current age, body mass index, smoking, physical activity level, and alcohol intake, were -4.3 (95% confidence interval (CI): -12.8, 4.3) and -6.1 (95% CI: -10.8, -1.5) mmHg/kg, respectively. In unpaired analysis among all twins, the equivalent values were -0.1 (95% CI: -4.0, 3.8) mmHg/kg for systolic pressure and -0.4 (95% CI: -2.9, 2.2) mmHg/kg for diastolic pressure, while in within-pair analysis the values were -0.9 (95% CI: -6.4, 4.6) mmHg/kg for systolic pressure and -0.2 (95% CI: -4.1, 3.7) mmHg/kg for diastolic pressure. The results suggest that in-utero growth restriction in twins is not a major determinant of their blood pressure as adults.     

Heart rate, employment status, and prevalent ischaemic heart disease confound relation between cereal fibre intake and blood pressure.

Cross sectional data from a survey of 2512 men aged 45-49 years were used to examine the confounding effects of heart rate, employment, and ischaemic heart disease (IHD) on the relation between cereal fibre intake and blood pressure. Daily cereal fibre intake (g/day) was associated with systolic pressure (r = -0.053, p less than 0.01), diastolic pressure (r = -0.057, p less than 0.01), and heart rate (r = -0.071, p less than 0.01). The associations were strengthened in employed men and inapparent in unemployed men. Unemployed men had more IHD than employed men. Persons with any manifestation of IHD had significantly higher blood pressure and heart rates but ate less cereal fibre (7.0 v 7.9 g/day, p less than 0.001) than those without IHD, regardless of employment status. In employed men, after adjustment for age, body mass index, prevalent IHD, and heart rate, systolic pressure changed -0.186 mmHg (95% CI = -0.362, -0.009) and diastolic pressure changed -0.111 mmHg (95% CI = 0.228, 0.005) for each gram of cereal fibre eaten daily. The association between cereal fibre and blood pressure was inapparent in unemployed men. Heart rate, employment, and prevalent IHD confound the association between cereal fibre intake and blood pressure. Future work concerning this relationship will have to account for the effects of these variables.     

Reproducibility and predictive values of routine blood pressure measurements in children. Comparison with adult values and implications for screening children for elevated blood pressure

A study of the variability of blood pressure was conducted among a total of 780 Massachusetts children, 335 children in East Boston and 445 children in Brookline, ages 8-18 years. All children had their blood pressure measured with a standard mercury sphygmomanometer in a school setting on four visits one week apart with three measurements per visit. In East Boston, repeat measurements were made for the same children for four consecutive years. A nested random effects model was used to estimate between- and within-visit variance components. For children aged 8-12 years, these were, respectively, 33.1, 12.0 in boys and 31.2, 11.1 in girls for systolic blood pressure and 57.7, 21.3 in boys and 56.6, 22.6 in girls for systolic muffling blood pressure (Korotkoff phase 4). For children aged 13-18 years of age, they were, respectively, 41.1, 11.8 in boys and 35.2, 12.2 in girls for blood pressure and 40.6, 15.5 in boys and 36.1, 11.4 in girls for diastolic blood pressure (Korotkoff phase 5). Within-person variability for systolic pressure was comparable to previously published data for 434 white adults ages 30-49 years not on antihypertensive medications; however, within-person variability for diastolic pressure was considerably higher in the children, accounting for over 75% of total variability among 8-12-year-old children, compared with 27% for adults. No meaningful effects of age, sex, or blood pressure level on variability of systolic pressure were found. However, age and level of blood pressure each had a large and independent inverse association with variability of diastolic pressure; variance components for younger children (ages 8-12 years) and children with low diastolic pressure (less than 60 mmHg) were approximately twice as large as for older children (ages 13-18 years) and children with diastolic pressure greater than or equal to 60 mmHg, respectively. Finally, predictive value estimates of blood pressure are provided for particular age-sex groups to enable one to efficiently identify children whose true mean level of blood pressure exceeds the 90th percentile for their age-sex group with minimum misclassification. Because of the substantial variability of diastolic pressure in young children, resulting in relatively low predictive value estimates, systolic pressure (either alone or in combination with diastolic pressure) may be more useful as the primary tool for screening children under age 13 years for high blood pressure.     

Relation of mass screening blood pressure to usual 24-hour working day blood pressure variation and left ventricular hypertrophy]

Fifty-three regularly employed hypertensive men (HT group) aged 38 to 68 years, whose blood pressure measured at a health evaluation clinic was systolic blood pressure (SBP) greater than or equal to 160 mmHg and/or diastolic pressure (DBP) greater than or equal to 95, and 21 age-matched normal controls (NC group), whose SBP was less than 140 and DBP was less than 90 had their blood pressure monitored over 24 hours during a usual working day. Age and clinical pressure were 53.1 +/- 7.1 years (mean +/- SD) and 147 +/- 18/97 +/- 10 mmHg (SBP/DBP) in the HT group, and 52.7 +/- 8.9 and 117 +/- 8/78 +/- 7 in the NC group. In the HT group, blood pressure during work (146/96 mmHg) was similar to clinical blood pressure, while blood pressure at home (135/89 mmHg) was considerably lower than clinic measured values. In contrast, blood pressure variabilities in the NC group during non-sleep hours were less, and clinical measurement was lower than that at home (122/80 mmHg), and during work (126/82 mmHg). For those examined by echocardiogram (46 in HT and 21 in NC), end-diastolic left ventricular wall thickness (LVT), and left ventricular mass index (LVMI) correlated most strongly with pressure during work by partial correlation analysis with age as a covariant (LVT:: SBP: r = 0.47, DBP: r = 0.53 both p less than 0.001, and LVMI:: SBP: r = 0.29, DBP: r = 0.25 both p less than 0.25). Clinical blood pressure as well as blood pressure at home and during sleep correlated significantly with LVT. These findings suggest that the blood pressure measurements obtained at a mass screening clinic, although infrequent, have important implications in relation to cardiac organ damage and for providing an estimate of blood pressure during work for hypertensives.     

Blood lead concentration, renal function, and blood pressure in London civil servants

Blood lead concentration was measured in 398 male and 133 female London civil servants not subject to industrial exposure to heavy metals. The relation between blood lead and serum creatinine concentrations and blood pressure were examined. Blood lead concentration ranged from 0.20 to 1.70 mumol/l with a geometric mean concentrations of 0.58 mumol/l in men and 0.46 mumol/l in women (p less than 0.001). In women blood lead concentration increased with age (r = +0.27; p = 0.002). In the two sexes blood lead concentration was positively correlated with the number of cigarettes smoked a day (men r = +0.17 and women r = +0.22; p less than or equal to 0.01), with the reported number of alcoholic beverages consumed a day (men r = +0.34 and women r = 0.23; p less than 0.01), and with serum gamma-glutamyltranspeptidase (men r = +0.23 and women r = +0.14; for men p less than 0.01). Blood lead concentration was not correlated with body weight, body mass index, and employment grade. In men 14% of the variance of blood lead concentration was explained by the significant and independent contributions of smoking and alcohol intake and in women 16% by age, smoking, and alcohol consumption. In men serum creatinine concentration tended to rise by 0.6 mumol/l (95% confidence interval from -0.2 to +1.36 mumol/l) for each 25% increment in blood lead concentration. In men and women the correlations between blood lead concentration and systolic and diastolic blood did not approach statistical significance. In conclusion, in subjects not exposed to heavy metals at work gender, age, smoking, and alcohol intake are determinants of blood lead concentration. At a low level of exposure, lead accumulation may slightly impair renal function, whereas blood pressure does not seem to be importantly influenced. Alternatively, a slight impairment of renal function may give rise to an increase in blood lead concentration.     

Blood lead concentration, renal function, and blood pressure in London civil servants.

Blood lead concentration was measured in 398 male and 133 female London civil servants not subject to industrial exposure to heavy metals. The relation between blood lead and serum creatinine concentrations and blood pressure were examined. Blood lead concentration ranged from 0.20 to 1.70 mumol/l with a geometric mean concentrations of 0.58 mumol/l in men and 0.46 mumol/l in women (p less than 0.001). In women blood lead concentration increased with age (r = +0.27; p = 0.002). In the two sexes blood lead concentration was positively correlated with the number of cigarettes smoked a day (men r = +0.17 and women r = +0.22; p less than or equal to 0.01), with the reported number of alcoholic beverages consumed a day (men r = +0.34 and women r = 0.23; p less than 0.01), and with serum gamma-glutamyltranspeptidase (men r = +0.23 and women r = +0.14; for men p less than 0.01). Blood lead concentration was not correlated with body weight, body mass index, and employment grade. In men 14% of the variance of blood lead concentration was explained by the significant and independent contributions of smoking and alcohol intake and in women 16% by age, smoking, and alcohol consumption. In men serum creatinine concentration tended to rise by 0.6 mumol/l (95% confidence interval from -0.2 to +1.36 mumol/l) for each 25% increment in blood lead concentration. In men and women the correlations between blood lead concentration and systolic and diastolic blood did not approach statistical significance. In conclusion, in subjects not exposed to heavy metals at work gender, age, smoking, and alcohol intake are determinants of blood lead concentration. At a low level of exposure, lead accumulation may slightly impair renal function, whereas blood pressure does not seem to be importantly influenced. Alternatively, a slight impairment of renal function may give rise to an increase in blood lead concentration.     

贵州省常住居民血压与睡眠时间关系调查

目的调查贵州省常住居民的睡眠时间和高血压的现状并探讨两者的关系。方法于2015-2016年基于多阶段分层抽样法,使用"中国重要心血管病患病率调查及关键技术研究的调查问卷"对贵州省15岁以上常住居民进行调查,并对其身高、体重、血压等进行体格检查。使用SPSS 22.0软件对所得数据进行描述分析和协方差分析。结果在调查的7412名常住居民中,男性3242人(43.74%),女性4170人(56.26%),总体平均年龄为(49.97±19.54)岁。调查对象中,有313例(4.22%)为睡眠时间不足,2832例(38.21%)为睡眠时间过长;正常血压2264例(30.54%),高血压患者2118例(28.58%)。在控制了年龄、BMI、疾病家族史等混杂因素后进行协方差分析,因变量为舒张压时,睡眠不足的人群舒张压比标准睡眠的舒张压高1.860 mm Hg(95%CI:0.594~3.125 mmHg,P=0.004);睡眠过长的人群舒张压比标准睡眠的舒张压高2.267 mmHg(95%CI:1.214~3.319 mmHg,P<0.001)。因变量为收缩压时,睡眠不足的人群收缩压比标准睡眠的收缩压高3.609 mmHg(95%CI:1.001~6.216 mmHg,P=0.007);睡眠过长的人群收缩压比标准睡眠的收缩压高4.322 mmHg(95%CI:2.154~6.490 mmHg,P<0.001)。结论调查对象中睡眠时间不足和睡眠时间过长的发生率较高,睡眠时间对高血压存在影响,睡眠时间不足或睡眠时间过长都会导致舒张压和收缩压的上升。     

Migration, blood pressure pattern, and hypertension: the Yi Migrant Study.

Rural-urban migration provides an ideal opportunity to examine the effects of environment and genes on blood pressure. The effect of migration on the Yi people of China was studied. The Yi people live in a remote mountain area in southwestern China. In 1989, blood pressure was measured in 14,505 persons (8,241 Yi farmers, 2,575 urban Yi migrants, and 3,689 Han urban residents) aged 15-89 years. Different patterns were seen for men and women. Among the men, Yi farmers had the lowest mean blood pressure, the least rise in blood pressure with age (systolic blood pressure, 0.13 mmHg/year; diastolic blood pressure, 0.23 mmHg/year), and the lowest prevalence of hypertension (0.66%). In contrast, both Yi migrant men and Han men had higher levels of mean blood pressure, rise in blood pressure with age (Yi migrants: systolic pressure, 0.33 mmHg/year; diastolic pressure, 0.33 mmHg/year; Han: systolic pressure, 0.36 mmHg/year; diastolic pressure, 0.23 mmHg/year), and prevalence of hypertension (Yi migrants, 4.25%; Han, 4.91%). Among the women, however, mean systolic pressure was higher in Yi farmers than in Yi migrants or in Han. Diastolic pressure was similar among the three groups. However, the Yi farmer women's age-related rise in blood pressure (systolic pressure, 0.06 mmHg/year; diastolic pressure, 0.14 mmHg/year) and their prevalence of hypertension (0.33%) were lower than those in the other two groups. Yi migrant women had an intermediate rise in blood pressure with age (systolic pressure, 0.37 mmHg/year; diastolic pressure, 0.23 mmHg/year) and prevalence of hypertension (2.40%). Han women had the greatest rise in blood pressure with age (systolic pressure, 0.56 mmHg/year; diastolic pressure, 0.36 mmHg/year) and the highest prevalence of hypertension (4.76%). For both men and women, the above differences were only partially explained by age, body mass index, heart rate, smoking, and alcohol use. This study, using standardized methods, demonstrates an important effect of migration on rise in blood pressure with age and on the prevalence of hypertension.     

Evaluating a community-based walking intervention for hypertensive older people in Taiwan: a randomized controlled trial

OBJECTIVE: To study the effect of a community-based walking intervention on blood pressure among older people. METHOD: The study design was a randomized controlled trial conducted in a rural area of Taiwan between October 2002 and June 2003. A total of 202 participants aged 60 years and over with mild to moderate hypertension was recruited. Participants randomized to the intervention group (n=102) received a six-month community-based walking intervention based on self-efficacy theory. A public health nurse provided both face-to-face and telephone support designed to assist participants to increase their walking. Control group participants (n=100) received usual primary health care. Primary outcome was change in systolic blood pressure and secondary outcomes were exercise self-efficacy, self-reported walking and diastolic blood pressure. RESULTS: At six-month follow-up the mean change in systolic blood pressure was a decrease of 15.4 mmHg and 8.4 mmHg in the intervention and control group, respectively. The difference in mean change between the two groups was -7.0 mmHg (95% CI, -11.5 to -2.5 mmHg, p=0.002). Improvement in exercise self-efficacy scores was greater among intervention group participants (mean difference 1.23, 95% CI, 0.5 to 2.0, p=0.001). Intervention group participants were more likely to report walking more (p<0.0005) but no differences were observed in diastolic blood pressure (p=0.19). CONCLUSIONS: Among hypertensive older people, a six-month community-based walking intervention was effective in increasing their exercise self-efficacy and reducing systolic blood pressure.     

Predictors of the development of hypertension: ten-year follow-up study in a community]

Predictors of the development of hypertension were examined in a 10-year follow-up study of normotensive Japanese adults. Subjects (n = 265), aged 30-69 years at entry, normotensive and with no past history of antihypertensive treatment at entry, were studied in terms of the relationship of various physical, biochemical, dietary, and lifestyle data to the subsequent development of hypertension (defined as systolic blood pressure (SBP) more than 140 mmHg and/or diastolic blood pressure (DBP) more than 90 mmHg and/or starting antihypertensive treatment) with analysis accomplished using univariate and multivariate life table methods. Univariate analyses by the generalized Wilcoxon test showed significantly higher incidence of hypertension in those subjects with SBP 120 mmHg or more (p < 0.001), DBP 75 mmHg or more (p < 0.001), serum glutamate oxaloacetate transaminase (GOT) 20 KU or more (p < 0.001), serum glutamate pyruvate transaminase (GPT) 15 KU or more (p < 0.001), serum gamma-glutamyl transpeptidase (gamma-GTP) 10 IU/l or more (p < 0.001), age 50 or older (p = 0.002), body mass index 22 kg/m2 or more (p = 0.012), and serum creatinine less than 1.2 mg/dl (p = 0.020) than in the other subjects. Multivariate analysis by the Cox proportional hazards model confirmed that relatively higher SBP (p < 0.001), lower serum creatinine (p < 0.001), higher gamma-GTP (p = 0.002), and higher age (p = 0.041) were independent and significant predictors of future hypertension.     

Relationship of hypertension to socioeconomic status in a West African population

Objectives: To determine whether hypertension rates were positively related to socio‐economic status (SES) in males in urban northern Nigerian civil servants in order to confirm this relationship previously observed in a southern Nigerian civil servant population which differed in tribal origin, religious practices and diet.

Methods: Civil servants were recruited from the Sokoto State ministries, Sokoto, Nigeria. Professionals and administrators were designated as higher SES, and clerks and laborers as lower SES. In addition to blood pressure, the height and weight of individuals, as well as their urinary sodium‐ and potassium‐creatinine, were also measured.

Results: The age‐adjusted occurrence of hypertension (systolic pressure ≥ 140 mmHg or diastolic pressure ≥ 90 mmHg or current use of hypertension medication) was similar in male higher (n = 155) and lower (n = 255) SES groups aged 25–54, 19.3% and 19.8%, respectively. However, the age‐adjusted rate of definite hypertension (systolic pressure ≥ 160 mmHg or diastolic pressure ≥ 95 mmHg or current use of hypertension medication) was considerably higher in the higher SES than in the lower SES men, 11.2% versus 3.6%. Age‐adjusted body mass index (BMI, kg/m²) was higher among the higher than in the lower SES group, 21.4 versus 20.4. Over‐night sodium excretion did not differ. Among female civil servants (n = 73) aged 20–44, there were few of higher SES (n = 19) precluding SES‐specific analyses. Total and definite hypertension rates among women were 17.2% and 5.5%, respectively. Mean BMI was 22.2. In logistic regression, definite hypertensive status was related to age group, BMI tertile, sodium excretion and SES in men and to sodium excretion in women.

Conclusion: Even in this very lean population, the higher risk for hypertension in males of higher SES was confirmed. This was explained, in part, by higher BMI.     

Blood cadmium in London civil servants

Blood cadmium was measured in 466 randomly selected London civil servants not exposed to heavy metals at work. Blood cadmium ranged from 3.6 to 75.6 nmol/L (0.4 to 8.5 micrograms/L) with a geometric mean of 6.4 nmol/L (0.7 micrograms/L) in nonsmokers and 13.6 nmol/L (1.5 micrograms/L) in smokers (p less than 0.001). Blood cadmium was higher in women than in men (9.5 versus 7.8 nmol/L) and was inversely correlated with employment grade (p less than 0.001). The associations with age, body weight and alcohol intake were not significant. After adjusting for gender and the number of cigarettes smoked per day, 36% of the variance of blood cadmium was explained, while the contribution of employment grade was not significant. There was an unexpected negative relationship between serum creatinine and blood cadmium in men (r = -0.16; p less than 0.01). This was not true in women (r = +0.03), but the correlation remained present in men after adjustment for age, body mass index and smoking. In contrast, in the two sexes, the correlations between blood pressure and blood cadmium were weak and not statistically significant. In conclusion, in unexposed subjects, gender and smoking are important determinants of blood cadmium. In addition, a low level of environmental exposure to cadmium is not associated with a deterioration of renal function or an increase in blood pressure.     

Blood pressure response to dietary sodium restriction in healthy normotensive children

To examine the effect of dietary sodium restriction on blood pressure, 149 healthy, normotensive children (64 males, 85 females) participated in a study designed to lower Na intake and maintain Na excretion at less than or equal to 75 mmol/d or half usual intake for 12 wk. Na excretion was decreased during the study period in both males (112.9 +/- 6.3 vs 53.4 +/- 3.6 mmol, p less than 0.001) and females (91.1 +/- 3.2 vs 41.1 +/- 1.9 mmol, p less than 0.001). Changes in systolic blood pressure were not significant in either sex but females showed a decrease (p less than 0.05) in diastolic and mean arterial blood pressures. Because blood pressure in children is correlated with age and body size, multiple linear regression was used to adjust blood pressure levels for age and weight. These analyses yielded small but significant decreases in systolic, diastolic, and mean arterial pressure measurements. The blood pressure response was heterogeneous but this variable response could not be attributed to varying degrees of compliance within families. These results suggest that compliance with modest Na restriction does not consistently lower blood pressure in normotensive children.     

The role of weight in the positive association between age and blood pressure

This study used cross-sectional data for 19,704 white men and 13,895 white women from the Chicago Heart Association Detection Project in Industry (November 1967 to January 1973) to investigate whether weight explains the association between age and blood pressure, and in particular, whether age is associated with blood pressure and hypertension in the absence of overweight. The relations among age, relative weight, and blood pressure were examined through assessment of mean blood pressure levels and prevalence of hypertension in 25 subgroups stratified by age (18-24, 25-34, 35-44, 45-54, and 55-64 years) and by relative weight (less than 100%, 100-109%, 110-119%, 120-134%, and greater than or equal to 135%). For all five relative weight groups, for both men and women, mean diastolic blood pressure was higher at successive ages. This phenomenon was also seen for systolic blood pressure after ages 35-44 years for men, and after ages 25-34 years for women. On the other hand, the higher the relative weight was, the higher the blood pressure was. Regression analysis demonstrated that the observed relation between age and blood pressure was consistent for all five relative weight groups, including those at desirable weight. These data indicate that for US subjects, age and blood pressure are generally associated in the absence of overweight.     

Factors associated with hypertension in Nigerian civil servants

BACKGROUND. Study of hypertension in segments of West African populations in transition toward Westernization may lead to better understanding of the high risk for hypertension among Westernized blacks. METHODS. Five hundred fifty-nine urban civil servants, ages 25-54, were recruited from six ministries of Bendel State, Nigeria. Blood pressure, physical measurements, urinary protein and glucose, fasting blood glucose, and demographic data were collected at the workplace. Subjects were classified as senior staff (professionals or administrators) or junior staff (non-administrators). RESULTS. Among 172 male senior staff, the age-adjusted rate of hypertension (diastolic blood pressure > or = 90 mm Hg, systolic blood pressure > or = 140 mm Hg, or on an antihypertensive medication) was 43% and occurrence rose dramatically from 21 to 63% across age groups 25-34 to 45-54, respectively. Among 266 male junior staff, the age-adjusted rate of hypertension was 23%, and occurrence did not rise with age. Logistic regression showed that body mass index (kg/m2), age, alcohol drinking, and being senior staff were all independently related to hypertension in men. On the other hand, the age-adjusted rate of hypertension in 121 women was 20% and was significantly related only to body mass index. CONCLUSION. Male urban civil servants appeared to have a risk for hypertension similar to that of U.S. black males. Age, body mass index, alcohol drinking, and other unidentified factors related to higher socioeconomic status were strong determinants of hypertension in this population.