Shift work is not associated with high blood pressure or prevalence of hypertension

Background

Working mostly at night has been suggested to be associated with upset of chronobiological rhythms and high blood pressure, but the evidence from epidemiological studies is weak.

Methods

In a cross-sectional survey, we evaluated the association between shift work and blood pressure, pre-hypertension and hypertension. In total, 493 nurses, nurse technicians and assistants, were selected at random in a large general hospital setting. Hypertension was diagnosed by the mean of four automatic blood pressure readings ≥140/90 mmHg or use of blood pressure lowering agents, and pre-hypertension by systolic blood pressure ≥120–139 or diastolic blood pressure ≥80–89 mmHg. Risk factors for hypertension were evaluated by a standardized questionnaire and anthropometric measurements. The association between the shift of work and blood pressure, pre-hypertension and hypertension was explored using univariate and multivariate analyses that controlled for risk factors for hypertension by covariance analysis and modified Poisson regression.

Results

The mean age of the participants was 34.3±9.4 years and 88.2% were women. Night shift workers were older, more frequently married or divorced, and less educated. The prevalence of hypertension in the whole sample was 16%, and 28% had pre-hypertension. Blood pressure (after adjustment for confounding) was not different in day and night shift workers. The prevalence of hypertension and pre-hypertension by shift work was not different in the univariate analysis and after adjustment for confounding (all risk ratios  = 1.0).

Conclusion

Night shift work did not increase blood pressure and was not associated with hypertension or pre-hypertension in nursing personnel working in a large general hospital.     

In urban South Africa, 16 year old adolescents experience greater health equality than children

Despite the strongly established link between socio-economic status (SES) and health across most stages of the life-course, the evidence for a socio-economic gradient in adolescent health outcomes is less consistent. This paper examines associations between household, school, and neighbourhood SES measures with body composition outcomes in 16 year old South African Black urban adolescents from the 1990 born Birth to Twenty (Bt20) cohort. Multivariable regression analyses were applied to data from a sub-sample of the Bt20 cohort (n = 346, 53% male) with measures taken at birth and 16 years of age to establish socio-economic, biological, and demographic predictors of fat mass, lean mass, and body mass index (BMI). Results were compared with earlier published evidence of health inequality at ages 9–10 years in Bt20. Consistent predictors of higher fat mass and BMI in fully adjusted models were being female, born post term, having a mother with post secondary school education, and having an obese mother. Most measures of SES were only weakly associated with body composition, with an inconsistent direction of association. This is in contrast to earlier findings with Bt20 9–10 year olds where SES inequalities in body composition were observed. Findings suggest targeting obesity interventions at females in households where a mother has a high BMI.     

Socioeconomic status as a risk factor for HIV infection in women in East, Central and Southern Africa: a systematic review

This is a critical, systematic review of the relationship between socioeconomic status (SES) and HIV infection in women in Southern, Central and Eastern Africa. In light of the interest in micro-credit programmes and other HIV prevention interventions structured to empower women through increasing women's access to funds and education, this review examines the epidemiological and public health literature, which ascertains the association between low SES using different measurements of SES and risk of HIV infection in women. Also, given the focus on structural violence and poverty as factors driving the HIV epidemic at a structural/ecological level, as advocated by Paul Farmer and others, this study examines the extent to which differences in SES between individuals in areas with generalized poverty affect risk for SES. Out of 71 studies retrieved, 36 studies met the inclusion criteria including 30 cross-sectional, one case-control and five prospective cohort or nested case-control studies. Thirty-five studies used at least one measurement of female's SES and fourteen also included a measurement of partner's SES. Studies used variables measuring educational level, household income and occupation or employment status at the individual and neighbourhood level to ascertain SES. Of the 36 studies, fifteen found no association between SES and HIV infection, twelve found an association between high SES and HIV infection, eight found an association between low SES and HIV infection and one was mixed. In interpreting these results, this review examines the role of potential confounders and effect modifiers such as history of STDs, number of partners, living in urban or rural areas and time and location of study in sub-Saharan Africa. It is argued that STDs and number of partners are on the causal pathway under investigation between HIV and SES and should not be adjusted as confounders in any analysis. In conclusion, it is argued that in low-income sub-Saharan Africans countries, where poverty is widespread, increasing access to resources for women may initially increase risk of HIV or have no effect on risk-taking behaviours. In some parts of Southern Africa where per capita income is higher and within-country inequalities in wealth are greater, studies suggest that increasing SES may decrease risk. This review concludes that increased SES may have differential effects on married and unmarried women and further studies should use multiple measures of SES. Lastly, it is suggested that the partner's SES (measured by education or income/employment) may be a stronger predictor of female HIV serostatus than measures of female SES.     

Age- and Sex-Specific Relationships between Household Income,Education, and Diabetes Mellitus in Korean Adults: The Korea National Health and Nutrition Examination Survey, 2008-2010

Background

To investigate the effects of age and sex on the relationship between socioeconomic status (SES) and the prevalence and control status of diabetes mellitus (DM) in Korean adults.

Methods

Data came from 16,175 adults (6,951 men and 9,227 women) over the age of 30 who participated in the 2008-2010 Korea National Health and Nutrition Examination Survey. SES was measured by household income or education level. The adjusted odds ratios (ORs) and corresponding 95% confidence intervals (95% CI) for the prevalence or control status of diabetes were calculated using multiple logistic regression analyses across household income quartiles and education levels.

Results

The household income-DM and education level-DM relationships were significant in younger age groups for both men and women. The adjusted ORs and 95% CI for diabetes were 1.51 (0.97, 2.34) and 2.28 (1.29, 4.02) for the lowest vs. highest quartiles of household income and education level, respectively, in women younger than 65 years of age (both P for linear trend < 0.05 with Bonferroni adjustment). The adjusted OR and 95% CI for diabetes was 2.28 (1.53, 3.39) for the lowest vs. highest quartile of household income in men younger than 65 (P for linear trend < 0.05 with Bonferroni adjustment). However, in men and women older than 65, no associations were found between SES and the prevalence of DM. No significant association between SES and the status of glycemic control was detected.

Conclusions

We found age- and sex-specific differences in the relationship of household income and education with the prevalence of DM in Korea. DM preventive care is needed for groups with a low SES, particularly in young or middle-aged populations.     

Intersalt revisited: further analyses of 24 hour sodium excretion and blood pressure within and across populations. Intersalt Cooperative Research Group.

OBJECTIVES--To assess further the relation in Intersalt of 24 hour urinary sodium to blood pressure of individuals and populations, and the difference in blood pressure from young adulthood into middle age. DESIGN--Standardised cross sectional study within and across populations. SETTING--52 population samples in 32 countries. SUBJECTS--10,074 men and women aged 20-59. MAIN OUTCOME MEASURES--Association of sodium and blood pressure from within population and cross population multiple linear regression analyses with multivariate correction for regression dilution bias. Relation of sample median daily urinary sodium excretion to difference in blood pressure with age. RESULTS--In within population analyses (n = 10,074), individual 24 hour urinary sodium excretion higher by 100 mmol (for example, 170 v 70 mmol) was associated with systolic/diastolic blood pressure higher on average by 3/0 to 6/3 mm Hg (with and without body mass in analyses). Associations were larger at ages 40-59. In cross population analyses (n = 52), sample median 24 hour sodium excretion higher by 100 mmol was associated with median systolic/diastolic pressure higher on average by 5-7/2-4 mm Hg, and estimated mean difference in systolic/diastolic pressure at age 55 compared with age 25 greater by 10-11/6 mm Hg. CONCLUSIONS--The strong, positive association of urinary sodium with systolic pressure of individuals concurs with Intersalt cross population findings and results of other studies. Higher urinary sodium is also associated with substantially greater differences in blood pressure in middle age compared with young adulthood. These results support recommendations for reduction of high salt intake in populations for prevention and control of adverse blood pressure levels.     

Initiation of hypertension in utero and its amplification throughout life.

OBJECTIVE--To determine whether the relation between high blood pressure and low birth weight is initiated in utero or during infancy, and whether it changes with age. DESIGN--A longitudinal study of children and three follow up studies of adults. SETTING--Farnborough, Preston, and Hertfordshire, England, and a national sample in Britain. SUBJECTS--1895 children aged 0-10 years, 3240 men and women aged 36 years, 459 men and women aged 46-54 years, and 1231 men and women aged 59-71 years. The birth weight of all subjects had been recorded. MAIN OUTCOME MEASURE--Systolic blood pressure. RESULTS--At all ages beyond infancy people who had lower birth weight had higher systolic blood pressure. Systolic blood pressure was not related to growth during infancy independently of birth weight. The relation between systolic pressure and birth weight became larger with increasing age so that, after current body mass was allowed for, systolic pressure at ages 64-71 years decreased by 5.2 mm Hg (95% confidence interval 1.8 to 8.6) for every kg increase in birth weight. CONCLUSIONS--Essential hypertension is initiated in fetal life. A raised blood pressure is then amplified from infancy to old age, perhaps by a positive feedback mechanism.     

Relation between birth weight and blood pressure: longitudinal study of infants and children.

OBJECTIVE--To study the relation between birth weight and systolic blood pressure in infancy and early childhood. DESIGN--Longitudinal study of infants from birth to 4 years of age. SETTING--A middle class community in the Netherlands. PARTICIPANTS--476 Dutch infants born in 1980 to healthy women after uncomplicated pregnancies. MAIN OUTCOME MEASURES--Systolic blood pressure and body weight measured at birth and at 3 months and 4 years of age; the relation between systolic blood pressure and birth weight as estimated by multiple regression models that include current weight and previous blood pressure and control for gestational age, length at birth, and sex. RESULTS--Complete data were available on 392 infants. At 4 years of age the relation between blood pressure and birth weight appeared to be U shaped; low and high birthweight infants had raised blood pressure. Current weight and previous blood pressure were also positively associated with blood pressure at that age. Low birthweight infants (birth weight < 3100 g) had a greater gain in blood pressure and weight in early infancy. High birthweight infants (birth weight > or = 3700 g) had high blood pressure at birth, and weight and blood pressure tended to remain high thereafter. CONCLUSIONS--Even among normal infants there seem to be subgroups defined by birth weight in which blood pressure is regulated differently. Future investigations are needed to examine the physiological basis of these differences. Studies of correlates of adult disease related to birth weight should investigate mechanisms related to increased risk separately in infants of low and high birth weight.     

Socioeconomic Status and Other Related Factors of Seasonal Influenza Vaccination in the South Korean Adult Population Based on a Nationwide Cross-Sectional Study

PurposeWe investigated the association between seasonal influenza vaccination in South Korea and socioeconomic status (SES) as well as other potential related factors.MethodsThe study was based on data obtained in the Korea National Health and Nutrition Examination Survey from 2010 to 2011. Education level and household income were used as indicators for SES. Univariate and multiple logistic regression analyses were used to evaluate SES and other demographic variables as related factors for influenza vaccination, the primary outcome.ResultsHigher household income was positively associated with higher vaccine uptake in the younger (19–49 years) group [adjusted odds ratio (aOR) 1.55, 95% confidence interval (CI) 1.08–2.23], whereas the low-income and low-education group had increased vaccination coverage than the middle-income and middle-education group in the older (≥ 50 years) group (aOR 1.36, 95% CI 1.09–1.69). Current smokers tend to be unvaccinated in all age groups. Among individuals aged ≥ 50, older age, mild to moderate alcohol consumption, regular exercise, and having co-morbidities were positively associated with vaccination, while those who self-reported their health status as good were less likely to be vaccinated.ConclusionsThe relationship between SES and seasonal influenza vaccination coverage differed between the age groups throughout the adult South Korean population. Public health policies need to address these inequalities.     

The prevalence of pre-hypertension and its association to established cardiovascular risk factors in south of Iran

ABSTRACT: BACKGROUND: Pre-hypertension is associated with an increased risk of the development of hypertension and subsequent cardiovascular disease and raises mortality risk. The aim of this study was to determine the prevalence of pre-hypertension and to explore the associations between pre-hypertension and established cardiovascular risk factors in a population-based sample of Iranian adults. Methods: In this cross-sectional study a representative sample of 892 participants aged [greater than or equal to]30 years was selected using a multistage cluster sampling method. After completion of a detailed demographic and medical questionnaire (gender, age, history of diabetes mellitus and hypertension, taking antihypertensive or hypoglycemic agents and history of smoking), all participants were subjected to physical examination, blood lipid profile, blood glucose, anthropometric and smoking assessments, during the years 2009 and 2010. Variables were considered significant at a p-value [less than or equal to] 0.05. Statistical analysis was performed using SPSS version 11.5 software. RESULTS: Pre-hypertension was observed among 300 (33.7%) subjects, 36.4% for men and 31.4% for women (p > 0.05). The pre-hypertensive group had higher levels of blood glucose and triglycerides, higher body mass index and lower percentage of smoking than did the normotensive group. Multivariate logistic regression analysis showed that obesity and overweight were the strongest predictors of pre-hypertension [odds ratio, 2.74: 95% CI (Confidence Interval), 1.62 to 4.62 p<0.001; odds ratio, 2.56, 95% CI, 1.74 to 3.77, p<0.001 respectively].Conclusions: Overweight and obesity has become important in the association with pre-hypertension in Iranian population. Primary prevention strategies should concentrate on reducing overweight and obesity if the prevalence of pre-hypertension is to be diminished in Iranian adults. Key words: pre-hypertension, cardiovascular risk factor, obesity, BMI.     

Socio-Economic Differences in Cardiovascular Health: Findings from a Cross-Sectional Study in a Middle-Income Country

Background

A relatively consistent body of literature, mainly from high-income countries, supports an inverse association between socio-economic status (SES) and risk of cardiovascular disease (CVD). Data from low- and middle-income countries are scarce. This study explores SES differences in cardiovascular health (CVH) in the Republic of Srpska (RS), Bosnia and Herzegovina, a middle-income country.

Methods

We collected information on SES (education, employment status and household’s relative economic status, i.e. household wealth) and the 7 ideal CVH components (smoking status, body mass index, physical activity, diet, blood pressure, total cholesterol, and fasting blood glucose) among 3601 participants 25 years of age and older, from the 2010 National Health Survey in the RS. Based on the sum of all 7 CVH components an overall CVH score (CVHS) was calculated ranging from 0 (all CVH components at poor levels) to 14 (all CVH components at ideal levels). To assess the differences between groups the chi-square test, t-test and ANOVA were used where appropriate. The association between SES and CVHS was analysed with multivariate linear regression analyses. The dependent variable was CVHS, while independent variables were educational level, employment status and wealth index.

Results

According to multiple linear regression analysis CVHS was independently associated with education attainment and employment status. Participants with higher educational attainment and those economically active had higher CVHS (b = 0.57; CI = 0.29–0.85 and b = 0.27; CI = 0.10–0.44 respectively) after adjustment for sex, age group, type of settlement, and marital status. We failed to find any statistically significant difference between the wealth index and CVHS.

Conclusion

This study presents the novel information, since CVHS generated from the individual CVH components was not compared by socio-economic status till now. Our finding that the higher overall CVHS was independently associated with a higher education attainment and those economically active supports the importance of reducing socio-economic inequalities in CVH in RS.     

The Influence of Physical Activity,Socioeconomic Status,and Ethnicity on the Weight Status of Adolescents

Objective: This study examined the effects of physical activity, television viewing, video game play, socioeconomic status (SES), and ethnicity on body mass index (BMI). Research Methods and Procedures: The sample was 2389 adolescents, 10 to 16 years of age (12.7 ± 1.0 years); 1240 (52%) females and 1149 (48%) males; 77% white and 23% African American; from rural (77%) and urban (23%) settings. BMI and skinfolds were directly assessed. All other data were obtained from questionnaires. Results: Watching television on non‐school days was related to being overweight (p < 0.005). However, when BMI analyses were adjusted for ethnicity and SES, there were no significant effects of television viewing on BMI (p > 0.061). Increased hours of video game play enhanced the risk of being overweight for both genders when analyses were adjusted for ethnicity and SES (p < 0.019). In males, participation in as little as one high‐intensity physical activity 3 to 5 days a week decreased the ethnic‐ and SES‐adjusted relative risk of being overweight (RR = 0.646; CI: 0.427 to 0.977). For females, the ethnic‐ and SES‐adjusted relative risk for being overweight was not significantly altered by physical activity. The logistic analyses further indicated the influence of low SES and African American ethnicity overshadowed any direct effect of television or videos. Discussion: Because weight status of male adolescents appears to be more related to exercise habits than to television or video game habits, increased participation in high‐intensity exercise appears to be important. For females, neither videos nor exercise habits appear to be related to risk of being overweight. However, ethnicity and SES may be important factors that can influence body weight status, while television viewing may be of some importance. Thus, programs to reduce obesity in female adolescent should focus their efforts in lower SES communities.     

Plasma reactive carbonyl species: Potential risk factor for hypertension

To study the role of oxidative stress in hypertension and pre-hypertension, this study analysed plasma levels of reactive carbonyl species (RCS) in 1204 Chinese Han adults. Results showed a statistically significant positive correlation (p < 0.001) between blood pressure and plasma RCS levels with or without being adjusted for covariates. Multivariate-adjusted odds ratio (OR) illustrated that, compared with the lowest quartile of plasma RCS levels, the highest quartile subjects had a 59% and a 130% increase in the risk for developing pre-hypertension and hypertension, respectively. The multi-interaction analysis manifested that the underlying mechanism of the increase of hypertensive risk or pre-hypertensive risk by overweight and unhealthy lifestyles might, at least in part, be through oxidative stress. In conclusion, these findings suggest that oxidative stress, as indicated by plasma RCS levels, are not the necessary consequence of pre-hypertension or hypertension, but reliable risk factors for developing pre-hypertension or hypertension in Chinese Han adults.     

Pre-Hypertension among Young Adults (20–30 Years) in Coastal Villages of Udupi District in Southern India: An Alarming Scenario

IntroductionAccording to Joint National Committee-7 (JNC-7) guidelines, a systolic blood pressure (SBP) of 120 to 139 mm Hg and/or diastolic blood pressure (DBP) of 80 to 89 mm Hg is considered as pre-hypertension. Existing evidence suggest that the cardiovascular morbidities are increasing among pre-hypertensive individuals compared to normal.ObjectiveTo assess the magnitude and factors associated with pre-hypertension among young adults (20–30 years) in coastal villages of Udupi Taluk (an area of land with a city or town that serves as its administrative centre and usually a number of villages), Udupi District, Karnataka state, India.DesignCommunity based cross sectional studySetting6 (out of total 14) coastal villages of Udupi Taluk, Karnataka state, India.Sample1,152 young adults (age group: 20–30 years) selected by stratified random sampling in 6 coastal villages of Udupi Taluk, Karnataka state, IndiaMethodA semi structured pre-tested questionnaire was used to elicit the details on socio-demographic variables, dietary habits, tobacco use, alcohol consumption, physical activity, family history of hypertension and stress levels. Anthropometric measurements and blood pressure were recorded according to standard protocols. Serum cholesterol was measured in a sub sample of the study population. Multivariate logistic regression was applied to identify the independent correlates of pre-hypertension among young adults (20–30 years).ResultsThe prevalence of pre-hypertension in the study population was 45.2% (95%CI: 42.4–48). Multivariate logistic regression analysis revealed that age group of 25–30 years (adj OR: 4.25, 95% CI: 2.99–6.05), white collared (adj OR: 2.29, 95% CI: 1.08–4.85) and skilled occupation (adj OR: 3.24, 95% CI: 1.64–6.42), students (adj OR: 2.46, 95% CI: 1.22–4.95), using refined cooking oil (adj OR: 0.53, 95% CI: 0.29–0.95), extra salt in meals (adj OR: 2.46, 95% CI: 1.52–3.99), salty food items (adj OR: 6.99, 95% CI: 3.63–13.48), pre-obese (adj OR: 1.66, 95% CI: 1.03–2.67) and obese (adj OR: 9.16, 95% CI: 2.54, 36.4) were the significant correlates of pre-hypertension.ConclusionIn the study population, prevalence of pre-hypertension among young adults (20–30 years) was high (45.2%). Biological (age 25–30 years, pre-obesity and obesity) and behavioral (sedentary occupation, intake of extra salt in meals/salty food and not using refined cooking oil) factors were associated with pre-hypertension. Study emphasizes the need of community based screening of pre-hypertension under National Rural Health Mission. It also provides apt information for the evidence based designing of interventions for lifestyle modifications among high risk young adults in the study area.     

Plasma reactive carbonyl species: Potential risk factor for hypertension

Abstract

To study the role of oxidative stress in hypertension and pre-hypertension, this study analysed plasma levels of reactive carbonyl species (RCS) in 1204 Chinese Han adults. Results showed a statistically significant positive correlation (p < 0.001) between blood pressure and plasma RCS levels with or without being adjusted for covariates. Multivariate-adjusted odds ratio (OR) illustrated that, compared with the lowest quartile of plasma RCS levels, the highest quartile subjects had a 59% and a 130% increase in the risk for developing pre-hypertension and hypertension, respectively. The multi-interaction analysis manifested that the underlying mechanism of the increase of hypertensive risk or pre-hypertensive risk by overweight and unhealthy lifestyles might, at least in part, be through oxidative stress. In conclusion, these findings suggest that oxidative stress, as indicated by plasma RCS levels, are not the necessary consequence of pre-hypertension or hypertension, but reliable risk factors for developing pre-hypertension or hypertension in Chinese Han adults.     

Socioeconomic conditions in childhood and ischaemic heart disease during middle age.

OBJECTIVE--To examine the association between socioeconomic conditions in childhood and ischaemic heart disease in middle aged men, including the role of physiological and behavioural risk factors. DESIGN--Prevalence study with extensive examination and testing and with recall of childhood conditions. SETTING--Population based study in Kuopio, Finland. SUBJECTS--Representative sample of 2679 men aged 42, 48, 54, and 60. MAIN OUTCOME MEASURES--Ischaemic findings on progressive maximal exercise test. RESULTS--Low socioeconomic style in childhood was associated with significantly higher prevalence of findings indicating ischaemias. Compared with those in the highest tertile of childhood socioeconomic conditions, the age adjusted odds ratio for subjects in the lowest tertile was 1.44 and for those in the middle tertile 1.35. Adjustment for years of cigarette smoking times the average number of cigarettes smoked, ratio of high density lipoprotein to low density lipoprotein cholesterol, fibrinogen and serum selenium concentrations, and adult height did not appreciably weaken the association. Adjustment for adult socioeconomic state resulted in a 16% decline in the association. The association was reduced to non-significance by adjustment for measures of prevalent cardiovascular illness. CONCLUSIONS--Socioeconomic state in childhood was significantly associated with ischaemic heart disease in middle aged men. Levels of risk factors measured at middle age did not account for this association, nor did adult height. Because childhood socioeconomic conditions precede the development of ischaemic heart disease the substantial impact of prevalent illness on the observed association suggests that ischaemic heart disease develops earlier in those with lower socioeconomic state during childhood.     

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.     

Blood pressure in prospective population based cohort of newborn and infant twins.

OBJECTIVE--To describe blood pressure in twins during infancy. DESIGN--Prospective study of cohort of twins. SETTING--Teaching hospital in Florida. SUBJECTS--166 viable twin pairs born between July 1976 and December 1989. MAIN OUTCOME MEASURES--Blood pressure and body weight at birth, at 14 days, and at 1, 3, 6, 9, and 12 months. RESULTS--Both systolic and diastolic pressure correlated with body weight throughout infancy (at birth r = 0.41, P < 0.001 and r = 0.42, P < 0.001 respectively; at 1 year r = 0.23, P < 0.001 and r = 0.26, P < 0.001 respectively). In infants weighing < 1500 g at birth mean blood pressure rose from about 45/25 mm Hg to 101/55 mm Hg from birth to the age of 1 year, while in infants weighing > 3000 g at birth it rose from 63/39 mm Hg to 100/61 mm Hg; corresponding mean body weights at 1 year were 7.86 kg and 9.88 kg. Differences in birth weight within pairs of monozygotic twins were negatively correlated with such differences in systolic blood pressure at 1 year (r = -0.37, P < 0.01). CONCLUSIONS--Blood pressure and body weights in twins showed strongly positive but generally declining correlations throughout infancy. Twins of lower birth weight showed a more rapid rate of rise in blood pressure during infancy. At 1 year the catch up in blood pressure exceeded that in body weight. Greater differences in birth weights between monozygotic twins were associated with smaller differences in systolic blood pressure at 1 year, suggesting that intrauterine environmental factors related to birth weight are important in determining blood pressure in infancy.     

Socioeconomic status and adiposity in childhood: a systematic review of cross-sectional studies 1990-2005

Background: Sobal and Stunkard's review (1989) of 34 studies from developed countries published after 1941, found inconsistent relationships between socioeconomic status (SES) and childhood adiposity. Inverse associations (36%), no associations (38%), and positive associations (26%) were found in similar proportions. In view of the trends in pediatric obesity, the relationship between SES and adiposity may have changed. Objective: To describe the cross‐sectional association between SES and adiposity in school‐age children from western developed countries in epidemiological studies since 1989. Methods and Procedures: PubMed database was searched to identify potentially relevant publications. Epidemiological studies from western developed countries presenting cross‐sectional data on the bivariate association between an SES indicator and objectively measured adiposity in childhood (5–18 years), carried out after 1989 were included. SES indicators included parental education, parental occupation, family income, composite SES, and neighborhood SES. Results: Forty‐five studies satisfied the review criteria. SES was inversely associated with adiposity in 19 studies (42%), there was no association in 12 studies (27%), and in 14 studies (31%) there was a mixture of no associations and inverse associations across subgroups. No positive SES‐adiposity associations were seen in unadjusted analyses. With parental education as the SES indicator, inverse associations with adiposity were found in 15 of 20 studies (75%). Discussion: Research carried out within the past 15 years finds that associations between SES and adiposity in children are predominately inverse, and positive associations have all but disappeared. Research is needed to understand the mechanisms through which parental social class influences childhood adiposity.     

Association between timing of hot water bathing before bedtime and night-/sleep-time blood pressure and dipping in the elderly: a longitudinal analysis for repeated measurements in home settings

ABSTRACT

Hot water bathing – a Japanese traditional practice – has not been evaluated for its association with night- and sleep-time blood pressure (BP) in large population. In this longitudinal analysis, bathing parameters and ambulatory BP were repeatedly measured for 2 nights in 758 Japanese elderly individuals. Participants were divided into three groups according to tertile values of time soaked in the bathtub (Duration: tertile value, 11 and 15 min), time from bathing-end to bedtime (Time before bedtime: tertile value, 42 and 106 min), and temperature of hot water in the bathtub (Water temp: tertile value, 40.3 and 41.2 °C). Participants’ mean age was 70.9 years, and mean night- and sleep-time systolic BP (SBP) and dipping were 115.1 ± 16.1, 114.2 ± 16.2 mmHg, and 14.2 ± 8.8%, respectively. Multivariable mixed-effect linear regression models adjusted for potential confounding factors suggested that nighttime SBP was significantly lower in the intermediate Time before bedtime group by 1.7 mmHg (95% CI, 0.2–3.1) and in the short group by 1.9 mmHg (95% CI, 0.1–3.7) than that in the long group. Dipping was significantly greater in the intermediate Time before bedtime group by 1.8% (95% CI, 0.7–2.9) and in the short group by 1.8% (95% CI, 0.6–3.1) than that in the long group. These associations were consistent regarding sleep-time SBP. Conversely, Water temp and Duration did not significantly associate with any ambulatory BP parameter. Remarkably, Time before bedtime significantly prolonged with increases in tertiles of Water temp (P for trend = 0.006). In conclusion, the findings of this study revealed that Japanese hot water bathing, especially the short time from bathing-end to bedtime, was associated with lower night- and sleep-time BP and greater dipping in an elderly population.