The relationship of age, body mass index and waist circumference with blood pressure in Bengalee Hindu male jute mill workers of Belur, West Bengal, India

A cross-sectional study of 150 adult Bengalee Hindu male jute mill workers of Belur, a suburb of Kolkata, West Bengal, India, was undertaken to study the relationship of age, body mass index (BMI) and waist circumference (WC) with systolic (SBP), diastolic (DBP) and mean arterial (MAP) blood pressure. The mean age and the BMI of the subjects were 40.7 years (S.D. = 15.2) and 23.2 kg/m2 (S.D. = 3.2), respectively. The mean SBP, DBP and MAP were 124.7 mmHg (S.D. = 7.8), 81.5 mmHg (S.D. = 5.7) and 95.9 mmHg (S.D. = 6.1), respectively. Age had similar significant (p < 0.001) correlations with BMI and WC. Age and WC were significantly correlated (p < 0.001) with all the three blood pressure variables. In general, the correlations of BMI with SBP (r = 0.24, p < 0.01), DBP (r = 0.15, n.s.) and MAP (r = 0.19, p < 0.05) were weaker. Age controlled multiple regression analyses demonstrated that BMI did not have a significant effect of any blood pressure variable. However, WC had a significant impact (p < 0.0001) on SBP (t = 7.068), DBP (t = 5.190) and MAP (t = 6.387), even after adjusting for the effect of age. Moreover, even after age adjustment, percent variations in SBP (20.7%), DBP (12.5%) and MAP (17.2%) explained by WC were high. This significant impact (p < 0.0001) of WC on SBP (t = 9.426), DBP (t = 8.349) and MAP (t = 9.642) remained even after controlling for the combined effects of age and BMI.     

Adiposity,central body fat distribution and blood pressure among young Bengalee adults of Kolkata,India: sexual dimorphism

A cross-sectional study of 174 men and 153 women of Bengalee ethnicity was undertaken to compare levels of adiposity, central body fat distribution and blood pressure. The mean age of both the sexes were similar (men = 20.1 years; women = 20.0 years). Significantly more women (n = 42, 27.5%) were overweight (body mass index, BMI > or = 25.0 kg/m2) as compared with men (19, 10.9%). Men were significantly taller and heavier. They also had significantly greater mean waist (WC) and mid upper arm (MUAC) circumferences compared with women. On the other hand, women had significantly (p < 0.001) greater mean BMI, biceps (BSF), triceps (TSF) and subscapular (SSF) skinfolds. The mean values of systolic (SBP), diastolic (DBP) and mean arterial (MAP) blood pressure were significantly greater among men. These significant differences existed even after controlling for BMI. Regression analyses revealed that sex had significant effect on all these variables even after controlling for BMI. Correlation studies showed that WC was found to be much more strongly correlated than BMI with SBP, DBP and MAP, in both sexes. However, when the effect of WC (along with BMI) was also controlled for, there was no significant sex difference in blood pressure.     

Familial resemblance of blood pressure with residual household environmental effects in consanguineous and nonconsanguineous families from Andhra Pradesh, India.

Familial aggregation of blood pressure (BP), both systolic (SBP) and diastolic (DBP), was examined in consanguineous and nonconsanguineous families from southern India. Path analysis of BP suggests inbreeding effects, with the genetic variance for SBP being lower in the sample that included inbred families. Specifically, genetic heritability for SBP was 38% in the nonconsanguineous sample but only 23% in the combined sample. Genetic heritability for DBP (30%) did not vary by sample, nor were sample differences in cultural heritability detected for either SBP (over 35%) or DBP (about 18%). These findings are remarkably similar to those in a French-Canadian population of Quebec; both reports found a considerably larger effect of the home environment on BP than previous studies.     

Genetic epidemiological study of blood pressure in a sedentary rural agricultural population of West Bengal, India

To study the genetic epidemiology of blood pressure (BP), data on 78 families were collected from a sedentary agricultural population of eastern India. The general levels of both systolic (SBP) and diastolic (DBP) blood pressures are found to be low (mean SBP = 106.41 mm Hg; mean DBP = 63.94 mm Hg). Trends of blood pressures with age are similar to those reported earlier (e.g., in the Framingham study). Environmental variables--e.g., occupation and tobacco use--do not have any direct significant effect on blood pressure variability in this population. Path analysis of family data shows a highly significant familial aggregation and yields a genetic heritability (maximum) estimate of 0.3 for both SBP and DBP. Sib-sib and mother-child correlation estimates are, respectively, 0.3 and 0.25. Father-child correlation estimates are 0.13 for SBP and near zero for DBP. A pseudopolygenic model yields the best fit to the data on SBP, while for DBP a proper resolution of various models considered could not be obtained.     

湘西地区农村7-15 岁儿童体重指数、血压及其相关性研究

目的:探讨湘西地区农村7-15岁儿童体重指数、血压及其相关性。方法:随机抽取湘西地区怀化市,吉首市,张家界市农村地区,于2011年1月到3月对7-15岁儿童进行调查。我们采用问卷调查法和体格检查法收集资料,采用中国肥胖问题工作组(WGOC)推荐的"中国学龄儿童青少年超重、肥胖筛查体重指数值分类标准"。高血压诊断采用文献中国儿童青少年血压参照标准评价肥胖和高血压。结果:1755名7-15岁儿童中,男性938人、占53.4%,女性817人占46.6%。男性BMI正常组838人、超重组7人和肥胖组30人,SBP分别为101.1±23.5 mmHg、103.9±12.0 mmHg、106.9±8.8 mmHg,DBP分别为66.7±9.0 mmHg、69.8±7.4 mmHg、71.7±9.1 mmHg。女性BMI正常组768人、超重组43人和肥胖组17人;SBP分别为101.3±35.1 mmHg、104.5±18.0 mmHg、109.1±9.8 mmHg,差异显著,有统计学意义(P<0.05),DBP分别为66.2±8.1 mmHg、71.1±8.8 mmHg、72.0±7.9 mmHg,差异显著,有统计学意义(P<0.05)。制年龄和性别后,BMI与收缩压(SBP)和舒张压(DBP)成独立正相关关系(P<0.05);BMI正常组、超重组和肥胖组的高SBP发生率分别是1.3%、7.1%和15.2%,高DBP发生率分别是4.5%、9.2%和17.4%,高SBP发生率分别是5.3%、13.3%和32.6%,差异显著,有统计学意义(P<0.05)。结论:儿童BMI与SBP和DBP密切相关,儿童超重和肥胖增加高血压的发生风险,且高血压发生率随肥胖程度的增加呈现成倍上升趋势。     

Influence of polymorphism of glutathione S-transferase M1 on systolic blood pressure of normotensive individuals

Studies have indicated that systolic (SBP) and diastolic (DBP) blood pressure are multi-factorial traits and significantly heritable. The aims of the present study are to assess whether the glutathione S-transferase M1 (GSTM1) and T1 (GSTT1) genotypes are associated with SBP and DBP of normotensive subjects and to ascertain whether the level of SBP and DBP given exposure to cigarette smoking is modified by the specific genetic polymorphisms of GSTM1 and GSTT1. This cross-sectional study was conducted on 140 subjects (49 females and 91 males) (mean age+/-SD: 38.7+/-14.7). The genotypes were determined using a polymerase chain reaction based method. Individuals were stratified according to the mean values of DBP and SBP, lower than or maximally same as the mean value defines as group I and higher than the mean value defines as group II. The logistic regression analyses were used. The best models fitted by logistic regression analysis for variables were associated with SBP and DBP. For analysis the combination of genotypes, sex, and smoking behavior was used as qualitative variables, and age, body mass index (BMI), and heart rate were used as covariates. Combination of "present-GSTT1, null-GSTM1" genotype (OR=0.001, 95% CI=0.00-0.439, P=0.025), heart rate (OR=1.065, 95% CI=1.018-1.114, P=0.006), and interaction between BMI and combination of "present-GSTT1, null-GSTM1" (OR=1.319, 95% CI=1.058-1.644, P=0.014) was associated with SBP. There was no association between either combination genotypes of GSTs or interaction of genotypes and smoking behavior on DBP. The present results suggest that the GSTM1 gene is one of the candidate genes that alter the baseline of SBP in normotensive individuals.     

Cigarette smoking, blood pressure and serum lipids and lipoproteins in middle-aged women

The relationship of cigarette smoking with blood pressure and serum lipids and lipoproteins was studied in the 3934 middle-aged women aged 40 to 59 years. After adjusting age, body mass index (BMI), alcohol intake and physical activity scores, the mean systolic and diastolic blood pressures (SBP and DEP, respectively) did not indicate dose-dependent relationships. The largest significant mean differences in SBP (4.6 mmHg), DBP (3.9 mmHg), high density lipoprotein cholesterol (HDL-C) (9.6 mg/dL), ratio of total cholesterol to HDL-C (TC/HDL-C) (0.8), triglycerides (TG) (22.9 mg/dL) and the logarithmic transformation of TG (Log TG) (0.26) were found between the non-smokers and smokers. When age, BMI, alcohol intake and physical activity scores were included in the forward stepwise multiple regression analyses, there were negative relationships found for cigarette smoking and SBP, DBP and HDL-C and positive relationships for cigarette smoking and TC/HDL-C, TG, Log TG and low density lipoprotein cholesterol. Although the results are somewhat variable, the present study shows cigarette smoking is negatively associated with SBP and DBP and unfavorably associated with serum lipids and lipoproteins in middle-aged women.     

The relationship between body mass index, blood pressure and pulse rate among normotensive and hypertensive participants in the third National Health and Nutrition Examination Survey (NHANES).

Obesity is associated with high insulin and leptin levels. Studies also suggest that high levels of insulin and leptin increase sympathetic nervous system (SNS) activity and engender increased chronotropy, vasoconstriction and antinatriuresis that may contribute to the pathogenesis of obesity related hypertension. Sympathetic modulation of cardiovascular responses requires good baroreceptor sensitivity and optimal vascular compliance. The vascular changes associated with isolated systolic hypertension (ISH) have been shown to modify baroreceptor sensitivity and vascular compliance and may mitigate sympathetic modulation of cardiovascular responses and attenuate the hypertensive effect of obesity. The purpose of this study is to examine the differences in the relationship between body mass index, pulse rate (PR), systolic blood pressure (SBP) and diastolic blood pressure (DBP) among participants with normal blood pressure and ISH using data from the third National Health and Nutrition Examination Survey. Data from 13,761 non-institutionalized adults 18 years and older not receiving antihypertensive therapy were analyzed. Results showed that PR, SBP and DBP increase with increasing BMI. The rise in PR, SBP and DBP with BMI is higher among participants with normal blood pressure than among those with ISH. We concluded that increasing level of obesity is associated with a rise in pulse rate and blood pressure but the effect of obesity on blood pressure and pulse rate might be weaker among participants with ISH.     

Lipoprotein lipase gene is in linkage with blood pressure phenotypes in Chinese pedigrees

To elucidate the mechanism of lipid metabolism in the genesis of essential hypertension (EH), we linked blood pressure (BP) phenotypes with the lipoprotein lipase (LPL) gene. Variance component and sib-pair linkage models were used to test the relationship of the polymorphisms in the LPL gene region and EH in 148 Chinese hypertensive families. Linkage evidence with systolic BP (SBP) and diastolic BP (DBP) was observed in a total population of 148 pedigrees with seven flanking microsatellite markers of the LPL gene, with a maximum two-point LOD score of 2.68 and a maximum multipoint LOD score (MLS) of 2.37 for SBP and a maximum MLS of 1.54 for DBP. Suggestive linkage results around this region were also obtained in northern and southern subsets by geographic distribution. In addition, quantitative-transmission/disequilibrium-test analyses showed that there was linkage between DBP and two single nucleotide polymorphisms in the LPL gene. This is the first report of linkage between LPL gene and DBP in the Chinese population. The LPL gene itself might explain our results or the LPL gene region might harbor some genes to explain the observed results to some degree and might contribute to the variation of BP in the Chinese population.     

Associations between Variation in CHRNA5-CHRNA3-CHRNB4, Body Mass Index and Blood Pressure in the Northern Finland Birth Cohort 1966

Background

The CHRNA5-CHRNA3-CHRNB4 gene cluster on 15q25 has consistently been associated with smoking quantity, nicotine dependence and lung cancer. Recent research also points towards its involvement in cardiovascular homeostasis, but studies in large human samples are lacking, especially on the role of the gene cluster in blood pressure regulation.

Methodology/Principal Findings

We studied the associations between 18 single nucleotide polymorphisms (SNPs) in CHRNA5-CHRNA3-CHRNB4 and systolic blood pressure (SBP), diastolic blood pressure (DBP), and body mass index (BMI) in 5402 young adults from the Northern Finland Birth Cohort 1966. We observed some evidence for associations between two SNPs and SBP and between six SNPs and BMI; the evidence for associations with DBP was weaker. The associations with the three phenotypes were driven by different loci with low linkage disequilibrium with each other. The associations appeared more pronounced in smokers, such that the smoking-increasing alleles would predict lower SBP and BMI. Each additional copy of the rs1948 G-allele and the rs950776 A-allele reduced SBP on average by −1.21 (95% CI −2.01, −0.40) mmHg in smokers. The variants associated with BMI included rs2036534, rs6495309, rs1996371, rs6495314, rs4887077 and rs11638372 and had an average effect size of −0.38 (−0.68, −0.08) kg/m² per an additional copy of the risk allele in smokers. Formal assessments of interactions provided weaker support for these findings, especially after adjustment for multiple testing.

Conclusions

Variation at 15q25 appears to interact with smoking status in influencing SBP and BMI. The genetic loci associated with SBP were in low linkage disequilibrium with those associated with BMI suggesting that the gene cluster might regulate SBP through biological mechanisms that partly differ from those regulating BMI. Further studies in larger samples are needed for more precise evaluation of the possible interactions, and to understand the mechanisms behind.     

Evidence of a rare gene for low systolic blood pressure in the Framingham Heart Study

A major risk factor for coronary heart disease in both men and women is elevated systolic blood pressure (SBP). We performed segregation analysis on age, sex-adjusted, and transformed systolic blood pressure data on 1,141 families from the Framingham cohort-offspring study using the segregation analysis program POINTER. The results of hypothesis testing revealed: (1) these data are consistent with familial transmission; (2) there is evidence for the transmission of a rare, major gene for low SBP with a gene frequency of q = 0.02; and (3) most of the transmissible component to SBP can be attributed to the polygenic background with H = 0.31.     

Variant in the FTO gene and biomarkers related to health in mature Slovak women

The purpose of this study was to investigate whether variant (rs178 17449, G/T) in the first intron of the fat mass and obesity-associated gene (FTO) was related to different obesity parameters and blood pressure in mature women from Slovakia. A total of 419 Slovak women (241 premenopausal and 178 postmenopausal) ranging in age from 39 to 65 years were recruited from different parts of Slovakia. The subgroups were categorized based on the WHO (1996) criteria. All participants gave written informed consent for participation in this study. Anthropometric parameters were measured using standard methods. Fat mass was examined by bioimpedance and blood pressure was measured in the morning during the medical examination. Genomic DNA was extracted from blood or saliva samples by the JET-QUICK Tissue DNA spine kit. The FTO variant was determined by PCR and restriction analysis according to the methodology of Hubacek et al. (2008). The obtained data were statistically analyzed by SPSS 17.0 for Windows. The FTO genotype and allele frequencies in the entire sample and in subgroups according to their menopausal and blood pressure status fell within the Hardy-Weinberg equilibrium. In postmenopausal women the FTO (rs178 17449) genotype was significantly associated with systolic blood pressure (SBP) (p = 0.024) in the dominant GG/GT vs.TT model and with diastolic blood pressure (DBP) (p = 0.030) in the recessive GG vs. GT/TT and the additive model (p = 0.043), respectively. In these postmenopausal women regression analysis showed a statistically significant effect of age, BMI and FTO dominant model on SBP, and of BMI on DBP among the other variables capable of inducing blood pressure differences. This study demonstrates that the SNP rs178 17449 in the FTO gene is associated with systolic and diastolic blood pressure but not with BMI and obesity variables, as already replicated in several populations throughout the world.     

Heritability of blood pressure increases during mental stress.

We studied the influence of mental stress on the contributions of genes and environment to individual variation in systolic (SBP) and diastolic (DBP) blood pressure by structural equation modelling in 320 adolescent male and female twins. Blood pressure data were collected during rest and during a reaction time and a mental arithmetic task. Univariate analyses of SBP and DBP showed familial aggregation for blood pressure. A genetic explanation for this resemblance was most likely, although during rest conditions a model that attributed familial resemblance to shared environmental factors, also fitted the data. There was no evidence for sex differences in heritabilities. Multivariate analyses showed significant heterogeneity between sexes for the intercorrelations of the blood pressure data measured under different rest and task conditions. Multivariate genetic analyses were therefore carried out separately in males and females. For SBP and DBP in females and for SBP in males an increase in heritabilities was seen for blood pressure measured during stress, as compared to rest measurements. The influence of shared environmental factors decreased during stress. For DBP in males no significant contributions of shared environment were found. The multivariate analyses indicated that the same genetic and environmental influences are expressed during rest and stress conditions.     

Effect of Sibutramine on Weight Loss and Blood Pressure: A Meta‐analysis of Controlled Trials

Objective: Sibutramine causes weight loss by suppressing the appetite and by promoting energy expenditure, but it can also increase blood pressure through a norepinephrine effect. The aim of this study was to provide a comprehensive meta‐analysis of randomized, controlled trials on the effects of sibutramine on blood pressure and weight loss. Research Methods and Procedures: Twenty‐one placebo‐controlled, double‐blind, randomized trials of sibutramine were identified using MEDLINE, EMBASE, and a manual search. The effect sizes of sibutramine on weight and systolic (SBP) and diastolic (DBP) blood pressure changes were estimated. Subgroup analyses were undertaken to explore the relationship between effect sizes and the study characteristics. Results: The effect size of sibutramine on weight change was ?1.00 (?1.17 to ?0.84), whereas the effect sizes on SBP and DBP changes were 0.16 (0.08 to 0.24) and 0.26 (0.18 to 0.33), respectively. By subgroup analysis, the effect sizes on weight loss were significantly larger when the dosage was ≥15 mg. The effect sizes on increased SBP were significantly larger when the initial body weight was ≥92 kg and the age was <44 years; similarly, the effect sizes on increased DBP were significantly larger when the initial weight was ≥92 kg. Discussion: Sibutramine showed a large effect on weight loss. Because blood pressure was found to be increased slightly, but significantly, sibutramine should be used cautiously in patients with borderline or high blood pressure. Additional studies on its effect on blood pressure are needed.     

Association of birth weight and current body size to blood pressure in female twins.

It has been proposed that low birth weight is associated with high levels of blood pressure in later life. The aim of this study was to assess the relationship of blood pressure to birth weight and current body size during growth and adulthood. A total of 711 female multiple births, with one group of 244 in their growth phase mean age 12.0 (2.3)(SD) years and the other of 467 adults (mean age 35.2 (12.6) years), had height, weight and both systolic (SBP) and diastolic (DBP) blood pressures measured, and self-reported their birth weight. Regression analyses were performed to assess the cross-sectional and within-pair associations of blood pressure to birth weight, with and without adjustments for current body size. Within-pair analysis was based on 296 twin pairs. Cross-sectionally, a reduction in birth weight of 1 kg was associated with 2 to 3 mm Hg higher age-adjusted SBP, which was of marginal significance and explained about 2% of the population variance. Adjustment for body mass index did not significantly change this association. Within-pair analyses found no association between birth weight and SBP or DBP,even after adjusting for current body size. After age, current body size was the strongest predictor of systolic BP. The weak association of blood pressure to birth weight cross-sectionally is of interest, but any within-pair effect of birth weight on blood pressure must be minimal compared with the effect of current body size.     

Association between Serum Leptin Levels and 24‐Hour Blood Pressure in Obese Women

Objective: To assess the relationship between serum leptin and 24‐hour blood pressure (BP) in obese women, according to body fat distribution. Research Methods and Procedures: A cross‐sectional study was carried out in a population of 70 nondiabetic, normotensive, obese women (40 with android and 30 with gynoid type of obesity) and 20 nonobese healthy women as a control group. All subjects underwent 24‐hour ambulatory BP monitoring. Blood samples were collected for serum leptin and plasma insulin measurements. Total cholesterol and high‐density lipoprotein cholesterol were also measured. Results: Serum leptin levels were significantly higher in obese subjects than in controls, and they were more elevated in android obese women than in gynoid ones. Leptin levels were positively related to body mass index (BMI), insulin, and waist and hip circumferences in the android group. Among gynoid subjects, leptin levels showed positive associations with BMI and insulin. In women with android obesity, strong positive correlations (p < 0.001) were found between leptin levels and 24‐hour systolic BP (SBP), daytime SBP, nighttime SBP, 24‐hour diastolic BP (DBP), and daytime DBP. Multiple regression analyses, including age, insulin and leptin concentrations, BMI, and waist and hip circumferences on 24‐hour and daytime SBP and DBP, showed that only leptin levels contributed to the variability of BP. Conclusions: Our study shows that serum leptin levels are directly related to 24‐hour BP levels in normotensive women with android fat distribution, independently of BMI.     

原发性高血压患者红细胞抗高血压因子对高血压...

The effects of antihypertensive factor (AHF) from erythrocytes of essential hypertensive human subjects on the systolic blood pressure (SBP) and diastolic blood pressure (DBP) in spontaneously hypertensive rats (SHR), renal hypertensive rats (RHR), Wistar-Kyoto rats (WKY) and Wistar rats were examined. Single intraperitoneal injection of AHF (1.6 mg/kg body weight) resulted in a significant decrease in SBP of SHR and RHR. At 10 min postinjection, AHF lowered the SBP in SHR by 34.0 mmHg. SBP recovered to the original level at 3 h. The maximal decrease of SBP in RHR by 92.5 mmHg was at 24h postadministration and the SBP did not recover until the 9th day. When AHF was administered via femoral vein (0.8 mg/kg body weight), the maximal decrease values of the SBP and the DBP were 42.8 and 48.2 mmHg in SHR at 12 min and 38.3 and 42.5 mmHg in RHR at 25 min postinjection respectively. The DBP in Wistar rats decreased considerably (from 96.7 +/- 12.9 to 83.3 +/- 11.7 mmHg) at 5 min postadministration of AHF, but no effect on DBP in WKY rats was observed. The depressor effect of AHF on SBP in RHR was dose-dependent. AHF could also antagonize the pressor effect of norepinephrine in Wistar rats.     

Relationships between blood pressure, polymorphism of angiotensin-converting enzyme (ACE), body composition and biochemical characteristics in elderly Slovaks

Epidemiological studies have demonstrated that several specific environmental factors and candidate genes influence the human variation in blood pressure. The aim of this study was to investigate variables associated with blood pressure; with a particular emphasis on the differences in insertion/deletion (I/D) polymorphism of the human angiotensin-converting enzyme (ACE), the body composition and the recognized risk factors for atherosclerosis among elderly males and females. A total of 374 participants (174 males and 200 females) aged from 60 to 90 years were recruited from different parts of Slovakia. The elderly were not bed-ridden, nor mentally impaired, they were able to manage their daily activities by themselves. The ACE I/D polymorphism was determined by PCR amplification of the ACE gene sequence. Body composition variables were obtained by bioelectrical impedance analysis, using the BIA 101 soft tissue-body impedance analyzer (Akern, S.r.l.). The subjects were determined to be hypertensive (blood pressure > or = 140/90 mm Hg) or normotensive (blood pressure < or = 140/90 mm Hg ). These two subgroups of males and females did not differ significantly in their mean ages. As expected, the hypertensive subjects of both sexes showed significantly higher mean values in systolic (SBP) and diastolic blood pressure (DBP), in body mass index (BMI), and in the mean values of their plasma glucose and extracellular water (ECW). The genotype distribution and allele frequencies in the whole sample (D = 0.5474, I = 0.4526) fell within the Hardy-Weinberg equilibrium. The frequency of the deleterious D allele in the normotensive (0.5532) and hypertensive (0.5516) subjects was not significantly different. The ACE I/D genotypes did not associate either with the systolic (p = 0.836) or diastolic BP (p = 0.629). From the other variables that may induce differences in blood pressure, a statistical effect was detected for glucose, Na/K, and Apo A1/ApoB ratios and physical activity on SBP, and for ApoA1, physical activity, BMI and total cholesterol on DBP.     

Cardiovascular risk factors in a French-Canadian population: resolution of genetic and familial environmental effects on blood pressure by using extensive information on environmental correlates.

Genetic and environmental influences on systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial blood pressure (MBP) were examined in 371 French-Canadian families by using path analysis. Familial environment was estimated with environmental indices constructed from as many as 14 (of a pool of more than 100) correlates of blood pressure (BP). Approximately 20% of the variance in BP can be accounted for by the composite index, and the types of variables and the direction of their effects vary as a function of age and of the multivariate context. Path analysis of the family data suggests that genetic heritability is relatively high in children (from 0.49 for SBP to 0.56 for MBP) but much smaller in adults (from 0.08 for DBP to 0.18 for SBP). The proportion of variability explained by familial environment is estimated to be the same in children and adults and is much higher than reported to date (from 0.30 for SBP to 0.42 for DBP). In addition, sibships share significant nontransmitted environmental effects, and there is no evidence to suggest specific maternal effects in the aggregation of BP. Two unique findings emerge from this study. First, unlike in most earlier studies, we were able to arrive at the same parsimonious model for each of the BP variables. Second, the familial environment accounts for a substantial proportion of the variability in BP, which has been considerably underestimated in earlier studies.     

Small area variations and factors associated with blood pressure and body-mass index in adult women in Accra,Ghana: Bayesian spatial analysis of a representative population survey and census data

BackgroundBody-mass index (BMI) and blood pressure (BP) levels are rising in sub-Saharan African cities, particularly among women. However, there is very limited information on how much they vary within cities, which could inform targeted and equitable health policies. Our study aimed to analyse spatial variations in BMI and BP for adult women at the small area level in the city of Accra, Ghana.Methods and findingsWe combined a representative survey of adult women’s health in Accra, Ghana (2008 to 2009) with a 10% random sample of the national census (2010). We applied a hierarchical model with a spatial term to estimate the associations of BMI and systolic blood pressure (SBP) and diastolic blood pressure (DBP) with demographic, socioeconomic, behavioural, and environmental factors. We then used the model to estimate BMI and BP for all women in the census in Accra and calculated mean BMI, SBP, and DBP for each enumeration area (EA). BMI and/or BP were positively associated with age, ethnicity (Ga), being currently married, and religion (Muslim) as their 95% credible intervals (95% CrIs) did not include zero, while BP was also negatively associated with literacy and physical activity. BMI and BP had opposite associations with socioeconomic status (SES) and alcohol consumption. In 2010, 26% of women aged 18 and older had obesity (BMI ≥ 30 kg/m²), and 21% had uncontrolled hypertension (SBP ≥ 140 and/or DBP ≥ 90 mm Hg). The differences in mean BMI and BP between EAs at the 10th and 90th percentiles were 2.7 kg/m² (BMI) and in BP 7.9 mm Hg (SBP) and 4.8 mm Hg (DBP). BMI was generally higher in the more affluent eastern parts of Accra, and BP was higher in the western part of the city. A limitation of our study was that the 2010 census dataset used for predicting small area variations is potentially outdated; the results should be updated when the next census data are available, to the contemporary population, and changes over time should be evaluated.ConclusionsWe observed that variation of BMI and BP across neighbourhoods within Accra was almost as large as variation across countries among women globally. Localised measures are needed to address this unequal public health challenge in Accra.

Sierra N. Clark and colleagues analyze spatial variations of blood pressure and body mass index, and associated factors in Ghanaian women.