Relationships between urinary cadmium levels and blood pressure were examined in a sample of 951 adult men and women who participated in the Second National Health and Nutritional Examination Survey (NHANES II). Among all participants, positive relationships were seen between urinary cadmium levels and both systolic and diastolic blood pressure (p less than 0.05 and p less than 0.01, respectively), after adjusting for age, sex, race, relative body weight, smoking status, and hypertensive medication use. However, analyses for subgroups determined by sex and smoking status were inconsistent. Among current smokers, urinary cadmium levels were significantly positively associated with both systolic and diastolic blood pressure for women, and with diastolic blood pressure for men. Yet among former smokers and lifelong nonsmokers of both sexes, urinary cadmium was not significantly associated with either systolic or diastolic blood pressure. Evidence that some hypertensive medications increase urinary cadmium excretion suggests that the positive associations seen among current smokers may reflect high urinary cadmium levels among hypertensives induced by hypertensive treatment. After treated hypertensives were removed from the analysis, regression coefficients relating blood pressure to cadmium dropped by a factor of two and lost statistical significance. We conclude that the present data provide little support for a causal association between systemic cadmium and hypertension at nonoccupational exposure levels. Further, conflicting results of previous studies may reflect failure to control adequately for age, smoking status, and hypertensive treatment.
Recent community studies have suggested that low level lead exposure is significantly associated with blood pressure in the general population. This finding is inconsistent with the results of recent occupational studies of lead exposed workers, although the occupational studies contained serious methodological weaknesses. The present study examined the relation between occupational lead exposure and diastolic and systolic blood pressure in randomly selected samples of 270 exposed and 158 non-exposed workers. Four exposure indicators were examined: employment at a lead battery plant nu a control plant, current blood lead value, current zinc protoporphyrin value, and time weighted average blood lead value. After controlling for other known risk factors such as age, education, income, cigarette usage, alcohol consumption, and exercise, the associations between exposure and blood pressure were small and non-significant. In the absence of a biologically feasible hypothesis regarding the mechanism by which low level lead exposure would influence blood pressure the present findings challenge the validity of the general population association.
The effect of commonly used oral contraceptives (OCs) on blood pressure is still unclear. The aim of this study was to examine the relationship between OCs use and blood pressure and the prevalence of hypertension in a population-based sample of Korean women.
A cross-sectional study was conducted using data from 3356 participants aged 35–55 years collected in the 2007–2009 Korea National Health and Nutrition Examination Surveys. OC use and demographic characteristics were obtained from participants using a questionnaire, and blood pressure was measured with a mercury sphygmomanometer.
Longer duration of OC use was positively associated with increasing levels of systolic blood pressure and diastolic blood pressure (p for trend <0.001). After adjusting for covariates, the odds ratio (OR) of hypertension was significantly increased in longer-term (>24 months) OC users (OR 1.96; 95% confidence interval (CI) 1.03–3.73) compared with those who had never used OCs. Additionally, use of OCs >24 months was associated with increased odds of prehypertension (adjusted OR 2.23; 95% CI 1.28–3.90) and hypertension or prehypertension (adjusted OR 2.13; 95% CI 1.37–3.32).
This study found a statistically significant association between OC use and blood pressure or hypertension among Korean women.
Oral contraceptive; Blood pressure; Hypertension; Prehypertension; KNHANES
The relationship between blood pressure and blood lead was examined in two population samples. One of these consisted of 1137 men aged 49 to 65 years, the other of 865 men and 856 women aged 18 to 64 years. Neither population had any known important exposure to lead, and the 95% ranges of blood lead levels were 6 to 26 micrograms/100 mL and 6 to 23 micrograms/mL in the men and 5 to 18 micrograms/100 mL in the women. No significant relationship between blood pressure and blood lead was detected in either of the population samples, and the regression coefficients suggest that if there were a real effect, then the mean difference in blood pressure per 10 micrograms difference in blood lead is likely to be 0.7 mm Hg in both systolic and diastolic pressures. In the survey of 1137 men, the rise in blood pressure was measured during the cold pressor test. This test is likely to be affected if lead were to affect neurogenic mediators of blood pressure. The mean change in systolic pressure was 24 mm Hg and the 95% range was -6 to 60 mm Hg, but there was no evidence of any association with blood lead level.
Five red blood cell cation transport systems (RBCTS), together with blood lead level and blood pressure, were measured in 129 male adult subjects who were not occupationally exposed to lead or subsequent to a course of treatment for hypertension. Blood lead was positively related with systolic blood pressure, and to a lesser degree with diastolic blood pressure. Blood lead was found significantly negatively related to one of the RBCTS, Na+,K+ cotransport, and in addition, Na+,K+ cotransport appeared negatively related to blood pressure. Final results showed that blood lead no longer accounts for an increase in systolic blood pressure when Na+,K+ cotransport was taken into account; the same trend was observed with diastolic blood pressure. These findings suggest that a blood lead-related Na+,K+ cotransport impairment could explain the blood pressure increase observed to parallel the blood lead increase.
Background. Few studies have shown that self-reported secondhand smoke exposure in never smokers is associated with high blood pressure. However, there are no studies investigating the relationship between secondhand smoke exposure, measured objectively by serum cotinine levels, and high blood pressure in never smokers.
Methods. We examined never smokers (n = 2027) from the National Health and Nutrition Examination Survey 2005–2008. Our exposure of interest was the secondhand smoke exposure estimated by serum cotinine level and our outcome was prehypertension (n = 734), defined as a systolic blood pressure of 120–139 mmHg or diastolic blood pressure of 80–89 mmHg. Results. We found that, in never smokers, serum cotinine levels were positively associated with prehypertension. Compared to those with cotinine levels in the lowest quartile (≤0.024 ng/mL), the multivariable odds ratio (95% confidence interval) of prehypertension among those with cotinine levels in the highest quartile (≥0.224 ng/mL) was 1.45(1.00, 2.11); P trend = 0.0451. In subsequent subgroup analyses, the positive association was found to be stronger among men, non-Whites, and non-obese subjects. Conclusion. Higher secondhand smoke exposure measured objectively by serum cotinine levels was found to be associated with prehypertension in certain subgroups of a representative sample of the US population.
The National Heart, Lung and Blood Institute currently defines a blood pressure under 120/80 as “normal.”
To examine the independent effects of diastolic (DBP) and systolic blood pressure (SBP) on mortality and to estimate the number of Americans affected by accounting for these effects in the definition of “normal.”
DESIGN, PARTICIPANTS AND MEASURES
Data on adults (age 25–75) collected in the early 1970s in the first National Health and Nutrition Examination Survey were linked to vital status data through 1992 (N = 13,792) to model the relationship between blood pressure and mortality rate adjusting for age, sex, race, smoking status, BMI, cholesterol, education and income. To estimate the number of Americans in each blood pressure category, nationally representative data collected in the early 1960s (as a proxy for the underlying distribution of untreated blood pressure) were combined with 2008 population estimates from the US Census.
The mortality rate for individuals over age 50 began to increase in a stepwise fashion with increasing DBP levels of over 90. However, adjusting for SBP made the relationship disappear. For individuals over 50, the mortality rate began to significantly increase at a SBP ≥140 independent of DBP. In individuals ≤50 years of age, the situation was reversed; DBP was the more important predictor of mortality. Using these data to redefine a normal blood pressure as one that does not confer an increased mortality risk would reduce the number of American adults currently labeled as abnormal by about 100 million.
DBP provides relatively little independent mortality risk information in adults over 50, but is an important predictor of mortality in younger adults. Conversely, SBP is more important in older adults than in younger adults. Accounting for these relationships in the definition of normal would avoid unnecessarily labeling millions of Americans as abnormal.
blood pressure; hypertension; guidelines; mortality
This paper proposes an alternative analysis of the statistically significant blood pressure/blood lead relationship reported for males, ages 12 to 74, based on data from the second National Health and Nutrition Examination Survey. Because of the substantial decline, both for blood lead levels and blood pressures, during the 4-year survey period, there is considerable interest in the extent to which this association can be attributed to concurrent secular trends. The statistical methods illustrate the use of a randomization model-based approach to testing the statistical significance of the partial correlation between blood lead level and diastolic blood pressure, adjusting for age, body mass index, and the 64 sampling sites. The resulting analyses confirm that the significant linear association between blood lead levels and diastolic blood pressures cannot be dismissed as a spurious association due to concurrent secular trends in the two variables across the 4-year survey period. In a conservative approach to this investigation, a randomization model-based test statistic, using the actual level of the natural log of blood lead and diastolic blood pressure, remained statistically significant at the 5% level, even when averaging the association across 478 subgroups formed by the cross-classification of age, body mass index, and the 64 sampling sites.
The purpose of this study was to find out the effect of lead exposure on systolic and diastolic blood pressure, heme biosynthesis related and hematological parameters of automobile workers. For this study 30 automobile workers were selected and compared with 30 age matched healthy control subjects. Significantly increased blood lead (364%, P < 0.001) and urinary lead (176%, P < 0.001) levels were observed in automobile workers (study group) as compared to controls. Systolic blood pressure (5.32%, P < 0.05) and diastolic blood pressure (5.87%, P < 0.05) were significantly increased in the automobile workers as compared to controls. The significantly decreased non-activated erythrocyte δ-aminolevulinic acid dehydratase (δ-ALAD) (−18.51%, P < 0.01) and activated δ-ALAD (−13.29%, P < 0.05) levels were observed in automobile workers as compared to normal healthy control subjects. But the ratio of activated/non-activated δ-ALAD was significantly increased (43.83%, P < 0.001) in automobile workers as compared to controls. Excretions of δ-aminolevulinic acid (83.78%, P < 0.001) and porphobilinogen (37%, P < 0.001) in urine were significantly increased in the study group as compared to the controls. In automobile workers heamoglobin (−11.51%, P < 0.001), hematocrit (−4.06%, P < 0.05), mean corpuscle volume (−3.34%, P < 0.05), mean corpuscle hemoglobin (−5.66%, P < 0.01), mean corpuscle hemoglobin concentration (−7.67%, P < 0.001), red blood cell count (−14.6%, P < 0.001) were significantly decreased and total white blood cell count (11.44%, P < 0.05) increased as compared to the controls. The results of this study clearly indicate that the absorption of lead is more in automobile workers and it affects on blood pressure, heme biosynthesis and hematological parameters observed in this study group.
Automobile workers; Blood lead (Pb-B); Urinary lead (Pb-U); Systolic and diastolic blood pressure; δ-Aminolevulinic acid (δ-ALA); δ-Aminolevulinic acid dehydratase (δ-ALAD); δ-Aminolevulinic acid synthetase (δ-ALAS); Porphobilinogen (PBG); Hematological parameters
We examined the relationship of blood lead level to systolic and diastolic blood pressure in a longitudinal study of 89 Boston, MA, policemen. At the second examination blood lead level and blood pressure were measured in triplicate. Blood pressure measurements were taken in a similar fashion in years 3, 4, and 5. Multivariate analysis using a first-order autoregressive model revealed that after adjusting for previous systolic blood pressure, body mass index, age, and cigarette smoking, an elevated blood lead level was a significant predictor of subsequent systolic blood pressure. Bootstrap simulations of these models provided supporting evidence for the observed association. These data suggest that blood lead level can influence systolic blood pressure even within the normal range.
This report describes the 20-year blood pressure behaviour of 3869 selected young North American males.
Initial mean systolic and diastolic pressures were higher than those recorded five years later; after that pressures increased progressively. The effect of initial selection was evident for the first 10 years of exposure.
A significant relationship was demonstrated between all initial systolic and diastolic levels and the 20-year blood pressure behaviour. Systolic pressure was not affected by age until age 50 and diastolic until age 45. After that a significant relationship was demonstrated.
In 20 years multiple readings ≥ 140 and/or ≥ 90 mm. Hg were recorded in 26% of the population. Increases in pressure usually extended over many years. Commonly they were labile, fluctuating above and below 140/90 mm. Hg. In a small, clearly defined group, accelerated increases reached high levels in three to 10 years.
Lead exposure is associated with elevated blood pressure during pregnancy; however, the magnitude of this relationship at low exposure levels is unclear.
Our goal was to determine the association between low-level lead exposure and blood pressure during late pregnancy.
We collected admission and maximum (based on systolic) blood pressures during labor and delivery among 285 women in Baltimore, Maryland. We measured umbilical cord blood lead using inductively coupled plasma mass spectrometry. Multivariable models were adjusted for age, race, median household income, parity, smoking during pregnancy, prepregnancy body mass index, and anemia. These models were used to calculate benchmark dose values.
Geometric mean cord blood lead was 0.66 μg/dL (95% confidence interval, 0.61–0.70). Comparing blood pressure measurements between those in the highest and those in the lowest quartile of lead exposure, we observed a 6.87-mmHg (1.51–12.21 mmHg) increase in admission systolic blood pressure and a 4.40-mmHg (0.21–8.59 mmHg) increase in admission diastolic blood pressure after adjustment for confounders. Corresponding values for maximum blood pressure increase were 7.72 (1.83–13.60) and 8.33 (1.14–15.53) mmHg. Benchmark dose lower limit values for a 1-SD increase in blood pressure were < 2 μg/dL blood lead for all blood pressure end points.
A significant association between low-level lead exposures and elevations in maternal blood pressure during labor and delivery can be observed at umbilical blood lead levels < 2 μg/dL.
benchmark dose; blood pressure; hypertension; lead; pregnancy; risk assessment; umbilical cord
Scientists and regulators have sought to understand whether and how physiologic dysregulation due to chronic stress exposure may enhance vulnerability to the adverse health effects of toxicant exposures. We conducted a cross-sectional study to determine whether allostatic load (AL), a composite measure of physiologic response to chronic exposure to stress, amplifies the effect of lead exposure on blood pressure among middle-aged adults.
We analyzed associations between blood lead levels and blood pressure in a nationally representative sample of 8,194 U.S. adults (aged 40-65 years) participating in the National Health and Nutritional Examination Survey, 1999--2008. Outcomes were elevated systolic (≥ 140 mm Hg) and diastolic (≥ 90 mm Hg) blood pressure. AL was defined as the aggregate score of seven components, reflecting dysregulation of the cardiovascular, inflammatory, and endocrine systems.
Logistic regression models showed a linear dose-response relationship for quintiles of blood lead and elevated systolic blood pressure in the high AL group (p = 0.03) but not the low AL group (p = 0.24). Similarly, the relationship between lead exposure and elevated diastolic blood pressure was stronger among the high AL group than the low AL group. Within the high AL group, the fourth and fifth quintiles had significantly elevated odds of elevated blood pressure compared to lowest quintile [OR = 1.92, (95% CI, 1.07, 3.47) and OR =2.28 (95% CI, 1.33, 3.91), respectively]. In the low AL group, none of the quintile effects were significantly different than the referent group although there was evidence of a linear trend (p =0.03). The lead by AL interaction term was not statistically significant for either systolic or diastolic blood pressure models.
Results suggest that higher AL may amplify the adverse effects of lead on blood pressure. Future research should assess the implications of cumulative exposures to environmental and social stressors for regulatory decision-making.
Blood pressure; Cumulative impacts; Environmental health; Lead; Stress
Aims: Although lead exposure has, in the absence of mathematical modelling, been believed to elevate blood pressure in females, it is necessary to clarify the relation between lead and blood pressure by eliminating confounding factors in the analysis.
Methods: Blood lead was measured in 193 female workers, including 123 lead exposed workers. Possible confounding factors were controlled by multiple regression analyses.
Results and Conclusion: Blood lead above 40 µg/dl was found to be the most potent factor for elevating systolic/diastolic blood pressure. Aging, urine protein, and plasma triglyceride also contributed to systolic/diastolic/pulse pressure increase, but hypertensive heredity did not. Data suggested that lead induced changes in lipoprotein metabolism may play an important role in the lead induced blood pressure increase in female workers.
San Francisco bus drivers have an increased prevalence of hypertension. This study examined relationships between blood lead concentration and blood pressure in 342 drivers. The analysis reported in this study was limited to subjects not on treatment for hypertension (n = 288). Systolic and diastolic pressures varied from 102 to 173 mm Hg and from 61 to 105 mm Hg, respectively. The blood lead concentration varied from 2 to 15 micrograms/dL. The relationship between blood pressure and the logarithm of blood lead concentration was examined using multiple regression analysis. Covariates included age, body mass index, sex, race, and caffeine intake. The largest regression coefficient relating systolic blood pressure and blood lead concentration was 1.8 mm Hg/ln (micrograms/dL) [90% C. I., -1.6, 5.3]. The coefficient for diastolic blood pressure was 2.5 mm Hg/ln (micrograms/dL) [90% C. I., 0.1, 4.9]. These findings suggest effects of lead exposure at lower blood lead concentrations than those concentrations that have previously been linked with increases in blood pressure.
Mediterranean populations have low incidence rates of cardiovascular disease and hypertension that may be due, in part, to dietary factors, particularly a relatively high intake of monounsaturated fat as olive oil. In this study, nutritional components (as grams per 4200 kJ) (1 kcal = 4.2 kJ) from three-day food records were examined in association with resting blood pressure in a cross-sectional survey of 76 sedentary middle-aged American men, aged 30 to 55 years, with resting blood pressures below 160/100 mm Hg. Systolic and diastolic blood pressures correlated significantly and inversely with monounsaturated fat consumption. Polyunsaturated fat consumption also correlated inversely with diastolic blood pressure; however, this relationship became nonsignificant when adjusted for an index of regional adiposity that characterizes the male-type obesity pattern. Detailed analyses of specific fatty acids showed that the correlations with monounsaturates were specific to oleic acid, and the correlation with polyunsaturates was specific to linoleic acid. Multiple regression analysis suggested that 18.2% of the variance in systolic blood pressure and 23.2% of the variance in diastolic blood pressure were related to monounsaturated and polyunsaturated fat consumption and regional adiposity. Thus, increased consumption of monounsaturated fat is related inversely to resting blood pressure, although causality remains to be determined.
Adverse health effects of cadmium in adults are well documented, but little is known about the neuropsychological effects of cadmium in children, and no studies of cadmium and blood pressure in children have been conducted.
We examined the potential effects of low-level cadmium exposure on intelligence quotient, neuropsychological functions, behavior, and blood pressure among children, using blood cadmium as a measure of exposure.
We used the data from a multicenter randomized clinical trial of lead-exposed children and analyzed blood cadmium concentrations using the whole blood samples collected when children were 2 years of age. We compared neuropsychological and behavioral scores at 2, 5, and 7 years of age by cadmium level and analyzed the relationship between blood cadmium levels at 2 years of age and systolic and diastolic blood pressure at 2, 5, and 7 years of age.
The average cadmium concentration of these children was 0.21 μg/L, lower than for adults in the National Health and Nutrition Examination Survey (NHANES), but comparable to concentrations in children < 3 years of age in NHANES. Except for the California Verbal Learning Test for Children, there were no differences in test scores among children in different cadmium categories. For children with detectable pretreatment blood cadmium, after adjusting for a variety of covariates, general linear model analyses showed that at none of the three age points was the coefficient of cadmium on Mental Development Index or IQ statistically significant. Spline regression analysis suggested that behavioral problem scores at 5 and 7 years of age tended to increase with increasing blood cadmium, but the trend was not significant. We found no significant associations between blood cadmium levels and blood pressure.
We found no significant associations between background blood cadmium levels at 2 years of age and neurodevelopmental end points and blood pressure at 2, 5, and 7 years of age. The neuropsychological or hypertensive effects from longer background exposures to cadmium need further study.
behavior; blood pressure; cadmium; children; clinical trial; intelligence; neurodevelopment
The relationship between blood pressure, ponderal index, sex, blood glucose, haemoglobin, serum uric acid, calcium cholesterol and creatinine, and albumin has been examined in 698 subjects aged between 44 and 49 years from the register of a group general practice. Sixty per cent of the variation in systolic pressure could be explained by statistically significant associations with diastolic pressure, sex, blood glucose, serum calcium, and cholesterol. The diastolic blood pressure (not corrected for systolic pressure) was significantly related only to ponderal index, haemoglobin in men, and cholesterol in women. Pulse pressure was also positively related to the risk factors blood glucose, serum cholesterol, and calcium. The possibility is discussed that one or more of these variables reduce aortic compliance and that the serum calcium contributes to this end. Diastolic, but not systolic pressure, had a prime association with relative weight, obesity being only basically associated with an increase in diastolic pressure.
Several healthful dietary patterns appear to be effective at lowering blood pressure and preventing hypertension. However, the relationship between dietary patterns and hypertension among a representative Chinese population sample is unclear.
A nationally representative sample of 23 671 participants aged 18-59 years were recruited by the 2002 China National Nutrition and Health Survey. All participants had their blood pressure measured with standardized mercury sphygmomanometers. Hypertension was defined as systolic blood pressure ≥140 mmHg and/or diastolic blood pressure ≥90 mmHg. We conducted factor analysis using dietary information from a validated food frequency questionnaire to derive dietary patterns. Information of participants on physical activities, education level, annual household income, smoking status and family history of hypertension was collected by interviewer-administrated questionnaires.
Three major dietary patterns, defined as 'Western', 'traditional northern', and 'traditional southern', were identified. Participants with the highest quartile for the score of the Western pattern had significantly higher blood pressure comparing with counterparts in the lowest quartile. In contrast, participants in the top quartile for the score of the traditional southern pattern presented significantly lower blood pressure comparing with counterparts in the lowest quartile. In multivariate analyses the traditional northern pattern score was associated with an odds ratio (OR) of 1.30 (95% confidence interval (CI) 1.11-1.53, P for trend = 0.0001) comparing with the lowest quartile. The OR for the top quartile of score for the traditional southern pattern was 0.73 (95% CI, 0.59-0.89, P for trend = 0.0040) compared with the lowest quartile of traditional southern pattern score. However, the significant association between the traditional northern pattern and prevalence of hypertension disappeared after further adjusting for body mass index (BMI) (P for trend = 0.3), whereas the association between the traditional southern pattern and prevalence of hypertension persisted after further adjusting for BMI (P for trend = 0.01).
We observed a positive relationship between the traditional northern pattern and hypertension that was mediated through differences in BMI. In addition, the traditional southern pattern was significantly associated with lower odds of presenting with hypertension.
The relationship between elevated blood pressure and cardiovascular and cerebrovascular disease risk is well accepted. Both systolic and diastolic hypertension are associated with this risk increase, but systolic blood pressure appears to be a more important determinant of cardiovascular risk than diastolic blood pressure. Subjects for this study are derived from the Framingham Heart Study data set. Each subject had five records of clinical data of which systolic blood pressure, age, height, gender, weight, and hypertension treatment were selected to characterize the phenotype in this analysis.
We modeled systolic blood pressure as a function of age using a mixed modeling methodology that enabled us to characterize the phenotype for each individual as the individual's deviation from the population average rate of change in systolic blood pressure for each year of age while controlling for gender, body mass index, and hypertension treatment. Significant (p = 0.00002) evidence for linkage was found between this normalized phenotype and a region on chromosome 1. Similar linkage results were obtained when we estimated the phenotype while excluding values obtained during hypertension treatment. The use of linear mixed models to define phenotypes is a methodology that allows for the adjustment of the main factor by covariates. Future work should be done in the area of combining this phenotype estimation directly with the linkage analysis so that the error in estimating the phenotype can be properly incorporated into the genetic analysis, which, at present, assumes that the phenotype is measured (or estimated) without error.
This study was designed to evaluate the effects of a fruit and vegetable powder mix on cardiovascular health as determined by blood pressure and heart rate variability (HRV) in a chiropractic college faculty and student population.
Forty subjects were recruited in the study via a schoolwide e-mail notification and through personal contacts. NanoGreens (Biopharma Scientific, Inc, San Diego, CA) vegetable supplement drink was tested to document its effect on the blood pressure and HRV in relation to cardiovascular health.
After taking the supplement for 90 days, both systolic and diastolic blood pressures decreased significantly in the treatment group. The systolic blood pressure decreased from 140.4 ± 17.7 to 128 ± 14.2 mm Hg, and the diastolic blood pressure decreased from 90.2 ± 7.7 to 83.1 ± 7.4 mm Hg. No significant blood pressure decrease was observed in the control group (systolic blood pressure from 130.8 ± 16.3 to 131 ± 16.1 mm Hg and diastolic blood pressure from 83.6 ± 9.6 to 83.1 ± 7.9 mm Hg). Subject's body weight in pounds did not change significantly in the experimental group: from 193.5 ± 31.1 to 194 ± 31.3. The body weight in the control group showed an increase from 175.9 ± 27.4 to 178 ± 29.9, but it was not significant. The heart rate did not show any statistically significant changes. Time domain analysis of HRV showed an increase in the standard deviation of the average R-R intervals root mean square of successive interbeat intervals, but it did not reach statistical significance. Frequency analysis of HRV found an increase in the total power, but it did not reach a significant level.
It was concluded that taking the nutritional supplement for 90 days reduced blood pressure but not body weight in this group of subjects. The HRV was not affected by the supplement over the 3-month period. Larger studies should be conducted to determine effects on other populations.
Dietary supplements; Nutrition therapy; Blood pressure; Chiropractic
OBJECTIVE: 1) To determine whether African-American physicians, compared to caucasian physicians, were at increased risk to develop hypertension; and 2) to determine whether physicians' knowledge of cardiovascular risk factors influenced their pattern of exercise. DESIGN: A mailed survey of members of the American Medical Association (AMA) and the National Medical Association (NMA) was completed to assess health status and plans for retirement. RESULTS: High-normal blood pressure was defined as systolic blood pressure of 85-89 mmHg. Mild (stage-1) hypertension was defined as systolic blood pressure of 140-159 mmHg and diastolic blood pressure of 90-99 mmHg. Gender (male), age, and body mass index (BMI) were significantly correlated with elevated levels of selected blood pressure measures. Using regression analysis to control for gender, age, and BMI, ethnicity was identified as a fourth factor accounting for elevated blood pressure. NMA physicians had 3.25 times the risk of having systolic blood pressure in the mild (stage-1) hypertension range, 5.78 times the risk for blood pressure in the high-normal diastolic hypertension range, and 5.19 times the risk for blood pressure in the mild (stage-1) diastolic hypertension range. Medical specialty and type of psychological support were not significant predictors of elevated blood pressure. CONCLUSION: These data suggest that African-American physicians may be at an increased risk to develop abnormal blood pressure, compared to caucasian physicians, potentially affecting the number of physicians available to minority communities.
Analysis of data collected during the Canada Health Survey of 1978-1979 indicated a positive relationship between blood lead and blood pressure, but so weak that the range of lead-related variation among members of the general public was estimated to be at most 3.0 mm Hg of diastolic pressure. Even so, a blood lead level in excess of the median value of 10 micrograms/dL entailed a 37% higher risk of having diastolic pressure above 90 mm Hg. In a longitudinal study of lead foundry workers, an association was found between short-term changes in an individual's blood lead level and contemporary changes in diastolic pressure; this remained significant after allowance for age (or time) trends and for effects attributable to changes in body weight. Short-term changes in urinary cadmium levels were similarly predictive of diastolic pressure.
Studies in children suggest a weak association between blood lead concentration and blood pressure. To understand this better, we tested the strength of the association in children with elevated blood lead concentrations and whether succimer chelation changed blood pressure as it did blood lead. In a randomized clinical trial of 780 children with blood lead concentrations of 20–44 μg/dL at 12–33 months of age, we compared the systolic and diastolic blood pressure in the succimer-treated group and placebo group for up to 5 years of follow-up. We also analyzed the relation of blood lead to blood pressure. Children in the succimer group had lower blood lead concentrations for 9–10 months during and after treatment, but their blood pressure did not differ from those in the placebo group during this period. During 1–5 years of follow-up, children in the succimer group had systolic blood pressure 1.09 (95% confidence interval, 0.27–1.90) mmHg higher than did untreated children in a model with repeated measurements, but the difference in diastolic blood pressure was not statistically significant. No association between blood lead and blood pressure was found. Overall, there is no association between blood lead and blood pressure in these children with moderately high lead exposure, nor does chelation with succimer change blood pressure.
blood pressure; chelation; child; lead; succimer
There have been numerous studies assessing the association of diet and blood pressure but little is known about the association between less commonly used nutritional supplements and blood pressured. The purpose of this study was to quantify the use of dietary supplements and their potential association with blood pressure in a large population-based cohort of adults in the Midwest.
The Personalized Medicine Research Project cohort was the population source for the current study. The current study includes subjects with Dietary History Questionnaire (DHQ) data available as well as at least one clinical blood pressure measurement recorded in their electronic medical record. After excluding extreme outlying measurements, median systolic and diastolic blood pressure measurements were calculated for each individual and were compared for subjects who did and did not report taking one of a list of 37 different supplements listed on the DHQ more than once per week over the previous 12 months.
9,732 subjects had both blood pressure and DHQ data available. They ranged in age from 18 to 98 years (mean 56 years) and 3,625 (37%) were male. Nine of 37 supplements showed evidence for association with blood pressure: coenzyme Q10, fish oil, iron, bilberry, echinacea, evening primrose oil, garlic, goldenseal and milk thistle. With the exception of the mineral iron, mean systolic and diastolic blood pressures were higher for users of the specific supplements than non-users.
These results should not be interpreted as causal, nor can the direction of the association be assumed to be correct because the temporality of the association is unknown. We hope the observed significant associations will foster future research to evaluate blood pressure effects of dietary supplements.
Blood pressure; Dietary supplements