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1.
OBJECTIVE--To examine factors that influence blood pressure in children. DESIGN--Cross sectional study of children aged 5.0-7.0 years who had blood pressure measurements and for whom parental questionnaires were completed. SETTING--School based survey. SUBJECTS--3591 Children aged 5.0-7.5 years selected by stratified random sampling of primary schools in nine British towns (response rate 72%); 3591 were examined and their parental questionnaires were completed. Data were complete for birth rank in 3559, maternal age in 3542, maternal history of hypertension in 3524, and paternal history in 2633. RESULTS--Birth weight was inversely related to mean systolic blood pressure but only when standardised for current weight (weight standardised regression coefficient -1.83 mm Hg/kg (95% confidence interval -1.31 to -2.35). Mean diastolic pressure was similarly related to birth weight. Maternal age, birth rank, and a parental history of hypertension were all related to blood pressure. After standardisation for current weight a 10 year increase in maternal age was associated with a 1.0 mm Hg (0.4 to 1.6) rise in systolic pressure; first born children had systolic blood pressure on average 2.53 mm Hg (0.81 to 4.25) higher than those whose birth rank was greater than or equal to 4; and a maternal history of hypertension was associated with a systolic pressure on average 0.96 mm Hg (0.41 to 1.51) higher than in those with no such history. The effects described were largely independent of one another and of age and social class. The relation for birth rank was, however, closely related to that for family size. CONCLUSIONS--Influences acting in early life may be important determinants of blood pressure in the first decade. The relation between birth weight and blood pressure may reflect the rate of weight gain in infancy. The reasons for the relation with birth rank and maternal age are unknown; if confirmed they imply that delayed motherhood and smaller family size may be associated with higher blood pressure in offspring.  相似文献   

2.
OBJECTIVE--To evaluate the relative contributions of factors acting at different stages in life to regional differences in adult blood pressure. DESIGN--Prospective cohort study (British regional heart study). SETTING--One general practice in each of 24 towns in Britain. SUBJECTS--7735 Men aged 40-59 years when screened in 1978-80 whose geographic zone of birth and zone of examination were classified as south of England, midlands and Wales, north of England, and Scotland. Non-migrants (n = 3144) were born in the town where they were examined; internal migrants (n = 4147) were born in Great Britain but not in the town where they were examined; and international migrants (n = 422) were born outside Great Britain. MAIN OUTCOME MEASURES--Systolic and diastolic blood pressures and height. RESULTS--Regardless of where they were born, men living in the south of England had lower mean blood pressures than men living in Scotland (142.5/80.1 v 148.1/85.2 mm Hg). The effects of the place of birth and place of examination on adult blood pressure were examined in a multiple regression model. For internal migrants the modelled increase in mean systolic blood pressure across adjacent zones of examination was 2.1 mm Hg (95% confidence interval 1.3 to 2.9); for adjacent zones of birth the corresponding increase was 0.1 mm Hg (-0.7 to 0.7). The place of examination seemed to be a far more important determinant of mean adult blood pressure than the place of birth. Height is an accepted marker of genetic and early life influences. Regional differences in height were therefore analysed to test whether the multiple regression model could correctly distinguish between the influence of place of birth and place of examination. As expected, men born in Scotland were shorter on average than men born in the south of England irrespective of where they lived in Britain (172.6 cm v 175.1 cm for internal migrants). CONCLUSION--Regional variations in blood pressure were strongly influenced by where the men had lived for most of their adult lives rather than by where they were born and brought up. Among middle aged men, factors acting in adult life seemed to be more important determinants of regional differences in blood pressure than those acting early in life such as genetic inheritance, intrauterine environment, and childhood experience.  相似文献   

3.
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.  相似文献   

4.
OBJECTIVE--To determine whether reduced fetal and infant growth are associated with higher plasma fibrinogen and factor VII concentrations in adult life. DESIGN--Follow up study of men born during 1920-30 whose weights at birth and at 1 year had been recorded by health visitors, and men born during 1935-43 whose size at birth had been measured in detail. SETTING--Hertfordshire and Preston, England. SUBJECTS--591 men born in east Hertfordshire who still lived there and 148 men born in Preston who still lived in or close to the city. MAIN OUTCOME MEASURES--Plasma fibrinogen and factor VII concentrations. RESULTS--Among men in Hertfordshire mean plasma fibrinogen and factor VII concentrations fell with increasing weight at 1 year (from 3.21 g/l in men of less than or equal to 18 lb to 2.93 g/l in men greater than or equal to 27 lb and from 122% of standard to 103%; p less than 0.001, p less than 0.005 respectively). The trends were independent of cigarette smoking, alcohol consumption, body mass index, and social class. Neither plasma fibrinogen nor factor VII concentration was related to birth weight. In men in Preston, however, fibrinogen concentration fell progressively as the ratio of placental weight to birth weight decreased (p = 0.01). CONCLUSIONS--Reduced growth in fetal life and infancy is strongly related to high plasma concentrations of the haemostatic factors fibrinogen and factor VII. This may be a persisting response to impaired liver development during a critical early period.  相似文献   

5.
In a region where falciparum malaria is endemic and where pregnant women traditionally receive only curative treatment for parasitaemias and no chemoprophylaxis 65 placental biopsy specimens were examined histologically for malaria pigment. Twenty seven placentas had pigment, but parasitaemias had been diagnosed antenatally in only 12 of these women despite their frequent attendance at antenatal and other clinics. The incidence of parasitaemia in pregnant primigravidas was 17.7%, seven times greater than that in lactating primiparous mothers; pregnant primigravidas also had the highest incidence (67%) of pigmented placentas. First born babies with pigmented placentas had a mean (SD) birth weight of 2580 (260) g, significantly less than the 3150 (400) g of unaffected first babies. All babies weighing less than 2500 g at birth had pigmented placentas. Pigmentation was associated with parasitaemias in the second half of pregnancy, and, although some recovery from early parasitaemias may occur, the fetoplacental unit is inadequately protected by curative treatment alone. Chemoprophylaxis currently remains the procedure of choice.  相似文献   

6.
OBJECTIVE--To determine the effect of atenolol on the outcome of pregnancy in women with essential hypertension. DESIGN--Prospective, randomised, double blind, placebo controlled study. SETTING--Hospital clinic. PATIENTS--33 Women with mild essential hypertension (systolic blood pressure 140-170 mm Hg or diastolic pressure 90-110 mm Hg on two occasions at least 24 hours apart) consecutively referred to two obstetric medical clinics. Four patients in the placebo group were withdrawn from the study: control of blood pressure was inadequate in two, one developed breathlessness, and one changed her mind about participating. The mean gestation in the 29 remaining women on entry to the study was 15.9 weeks. MAIN OUTCOME MEASURES--Blood pressure and birth weight. INTERVENTION--14 Women received placebo. 15 Women received atenolol 50 mg daily initially, increasing until either the blood pressure was less than 140/90 mm Hg or a dose of 200 micrograms daily was reached. RESULTS--The mean blood pressure on entry was 148/86 mm Hg in the group given atenolol and 144/86 mm Hg in the group given placebo. During treatment the mean diastolic pressure was significantly reduced by atenolol compared with placebo (to 74 v 81 mm Hg; difference in means (95% confidence interval) 7.0 (2.9 to 10.0) mm Hg) but the effect on systolic pressure was marginal (132 v 136 mm Hg; 4.0 (-1.4 to 8.6) mm Hg). Babies in the atenolol group had a significantly lower birth weight than those in the placebo group (2620 g v 3530 g; 910 (440 to 1380)g). CONCLUSION--Atenolol given from the end of the first trimester in patients with mild hypertension is associated with intrauterine growth retardation. When taken in conjunction with the results of a previous study in which methyldopa was given these findings indicate that benefit is unlikely to result from treating mild essential hypertension in pregnancy.  相似文献   

7.
OBJECTIVE--To discover whether reduced fetal and infant growth is associated with non-insulin dependent diabetes and impaired glucose tolerance in adult life. DESIGN--Follow up study of men born during 1920-30 whose birth weights and weights at 1 year were known. SETTING--Hertfordshire, England. SUBJECTS--468 men born in east Hertfordshire and still living there. MAIN OUTCOME MEASURES--Fasting plasma glucose, insulin, proinsulin, and 32-33 split pro-insulin concentrations and plasma glucose and insulin concentrations 30 and 120 minutes after a 75 g glucose drink. RESULTS--93 men had impaired glucose tolerance or hitherto undiagnosed diabetes. They had had a lower mean birth weight and a lower weight at 1 year. The proportion of men with impaired glucose tolerance fell progressively from 26% (6/23) among those who had weighted 18 lb (8.16 kg) or less at 1 year to 13% (3/24) among those who had weighed 27 lb (12.25 kg) or more. Corresponding figures for diabetes were 17% (4/23) and nil (0/24). Plasma glucose concentrations at 30 and 120 minutes fell with increasing birth weight and weight at 1 year. Plasma 32-33 split proinsulin concentration fell with increasing weight at 1 year. All these trends were significant and independent of current body mass. Blood pressure was inversely related to birth weight and strongly related to plasma glucose and 32-33 split proinsulin concentrations. CONCLUSIONS--Reduced growth in early life is strongly linked with impaired glucose tolerance and non-insulin dependent diabetes. Reduced early growth is also related to a raised plasma concentration of 32-33 split proinsulin, which is interpreted as a sign of beta cell dysfunction. Reduced intrauterine growth is linked with high blood pressure, which may explain the association between hypertension and impaired glucose tolerance.  相似文献   

8.
OBJECTIVE--To examine whether birth weight is related to systolic blood pressure during adolescence. DESIGN--Retrospective (comparative) cohort study. The observers who traced and studied the subjects were unaware of their case-control status. SUBJECTS--330 subjects were born in Cardiff in 1975-7. Cases who were low birth weight at term (< 2500 g) were matched with controls of normal birth weight (3000-3800 g) at term. MAIN OUTCOME MEASURES--Systolic blood pressure measured by random zero sphygmomanometry in the subject''s right arm with the subject supine, corrected for size and age. RESULTS--The mean age at examination was 15.7 years. The mean systolic blood pressure of the cases was 105.8 mm Hg and of the controls 107.5 mm Hg. The corrected difference (95% confidence interval) in systolic blood pressure between the cases and controls was 1 mm Hg (-3 to +1 mm Hg; two tailed probability 0.33). CONCLUSION--Systolic blood pressure in adolescents of low birth weight is not significantly different from that of adolescents of normal birth weights.  相似文献   

9.
We compare blood pressure and hypertension between adult men on the USA mainland and in Puerto Rico born during 1886-1930 to test hypotheses about the link between cardiovascular health and large socioeconomic and political changes in society: (a) 8853 men surveyed in Puerto Rico in 1965 and (b) 1449 non-Hispanic White men surveyed on the mainland during 1971-1975. Systolic and diastolic blood pressure and hypertension were regressed separately on demographic and socioeconomic variables and cardiovascular risk factors. Mainland men not taking anti-hypertensive medication showed statistically significant improvements in systolic blood pressure and hypertension at the beginning of the century and men in Puerto Rico showed improvements in diastolic blood pressure but only during the last two quinquenniums. An average man born on the mainland during the last birth quinquennium (1926-1930) had 7.4-8.7 mmHg lower systolic blood pressure and was 61% less likely to have systolic hypertension than one born before 1901. On average Puerto Rican men born during 1921-1925 had approximately 1.7 mmHg lower diastolic blood pressure than men born before 1901. Analyses of secular trends in cardiovascular health complements analyses of secular trends in anthropometric indicators and together provide a fuller view of the changing health status of a population.  相似文献   

10.
Blood pressure was measured in a birth cohort of 5362 subjects at the age of 36. The prevalence of hypertension in men (blood pressure greater than 140/90 mm Hg) was almost twice that in women, although women received treatment more often. Deaths of fathers of subjects from hypertensive and ischaemic heart disease were associated with significantly higher mean systolic and diastolic pressures in both sexes. Cigarette smoking was not strongly associated with blood pressure in men and not associated at all in women. Of the social factors, low social class of family of origin was associated with high blood pressure in both sexes; but the strongest association was with current body mass, and birth weight also contributed. Differences in blood pressures between the sexes may have been related to protective biological factors, such as endogenous sex hormones, in women and also to differences in types of employment, smoking habits, and body mass. Differences in blood pressures related to the social class of family of origin may reflect long term influences of class differences on diet, exercise, and educational achievement. The importance of measuring secular trends in obesity and blood pressures is emphasised.  相似文献   

11.
In national samples of 9921 10 year olds and 3259 adults in Britain systolic blood pressure was inversely related to birth weight. The association was independent of gestational age and may therefore be attributed to reduced fetal growth. This suggests that the intrauterine environment influences blood pressure during adult life. It is further evidence that the geographical differences in average blood pressure and mortality from cardiovascular disease in Britain partly reflect past differences in the intrauterine environment. Within England and Wales 10 year olds living in areas with high cardiovascular mortality were shorter and had higher resting pulse rates than those living in other areas. Their mothers were also shorter and had higher diastolic blood pressures. This suggests that there are persisting geographical differences in the childhood environment that predispose to differences in cardiovascular mortality.  相似文献   

12.
13.
Variation in labelling of hypertension by individual general practitioners was studied during a continuous opportunistic screening programme for hypertension in a single general practice with 12 principals. All the general practitioners agreed to label as hypertensive patients with systolic pressures of greater than or equal to 200 mm Hg or diastolic pressures of greater than or equal to 110 mm Hg on three consecutive readings. The overall number of patients labelled hypertensive at the beginning of the screening programme was 505 and this rose to 801 after five years. There was a large variation in the numbers of patients recorded as hypertensive at the start of the screening period, with numbers ranging from eight to 112 for individual practitioners. The variation persisted during the screening period, with the numbers of patients detected by individual general practitioners ranging from four to 46. The average systolic and diastolic pressures recorded among these patients also varied between doctors, and only 24 out of 187 patients had their high pressures recorded on three occasions and so fully met the criteria for diagnosing hypertension. Clearly, general practitioners are following their own individual criteria in defining hypertension and taking into account factors other than just the measured blood pressure.  相似文献   

14.
Lamb survival is impaired in low birth weight lambs, and those that are slow to stand and suck. Many of the factors that influence lamb vigour, such as parity, litter size, and breed, may exert their effects, at least partially, before birth by influencing placenta development. Our hypothesis was that retarded lamb behavioural development was due to differences in placentation in these animals. Data were collected from Blackface and Suffolk lambs in the first 2 h after birth and placentas were collected when delivered. Suffolk lambs, which were behaviourally slower and had lower rectal temperatures than Blackface lambs, were associated with larger but less efficient placentas (placental efficiency defined as foetal weight supported per g placenta) with fewer foetal cotyledons than Blackface placentas. Triplet lambs were significantly slower than twin or single lambs to suck and had lower rectal temperatures. Although placenta efficiency increased with litter size, placenta and cotyledon weight, and cotyledon number increased with twinning but not thereafter. It seemed likely that triplet lambs suffered some placental insufficiency in comparison to other litter sizes. Lambs born to first parity mothers were slower to stand and reach the udder than lambs of more experienced ewes, and first parity ewes also had smaller and less efficient placentas although cotyledon number was not affected. Male lambs tended to be slower than female lambs for most behaviours, although rectal temperatures were not affected. The sire of the lamb also influenced lamb behaviour and rectal temperature. Both lamb sex and lamb sire influenced the average weight of placental cotyledons, thus some of the sire effect on the behaviour and birth weight of his progeny might be mediated through placental development. Lamb neonatal vigour was correlated with placental efficiency suggesting that lamb behaviour immediately after birth is related to placental development and function.  相似文献   

15.
OBJECTIVE: To assess the effect of size at birth, maternal nutrition, and body mass index on blood pressure in late adolescence. DESIGN: Population based analysis of birth weight corrected for gestational age, mother''s weight before pregnancy and weight gain in pregnancy, obtained from the Jerusalem perinatal study, and blood pressure and body mass index at age 17, available from military draft records. SETTING: Jerusalem, Israel. SUBJECTS: 10,883 subjects (6684 men and 4199 women) born in Jerusalem during 1974-6 and subsequently drafted to the army. MAIN OUTCOME MEASURES: Systolic and diastolic blood pressures measured at age 17 and their correlation with birth weight, size at birth, mother''s body mass index and weight gain during pregnancy, and height and weight at age 17. RESULTS: Systolic and diastolic blood pressures were significantly and positively correlated with body weight, height, body mass index at age 17, and with mother''s body weight and body mass index before pregnancy, but not with birth weight or mother''s weight gain in pregnancy. CONCLUSION: Variables reflecting poor intrauterine nutrition, including low maternal body mass index before pregnancy, poor maternal weight gain in pregnancy, and being born small for gestational age, were not associated with a higher blood pressure in late adolescence.  相似文献   

16.
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.  相似文献   

17.
One hundred pregnant women with hypertension (defined as diastolic blood pressure at or above 95 mm Hg) were allocated at random to treatment with methyldopa or oxprenolol and were compared with nonhypertensive controls matched according to parity and gestation at delivery. The patients were also stratified into those entering the study early (before 32 weeks'' gestation) and those entering late (after 32 weeks'' gestation). Although there were no differences in diastolic blood pressure between the hypertensive groups before or during treatment, in the early entry group the systolic blood pressure at entry of those allocated to oxprenolol was significantly higher than that of those receiving methyldopa; this difference remained throughout the treatment period. Also in the early entry group further increments of drug treatment were required to control blood pressure of patients receiving oxprenolol than in those receiving methyldopa. The eventual fetal outcome for all patients treated with methyldopa was the same as that for those treated with oxprenolol; birth weight, placental weight, head circumference, and Apgar score were not significantly different and there were no stillbirths in either group.  相似文献   

18.
OBJECTIVES: To clarify the type of fetal growth impairment associated with increased blood pressure in adult life, and to establish whether this association is influenced by obesity and is mediated through impairment of insulin action. DESIGN: Cross sectional survey with retrospective ascertainment of size at birth from obstetric archives. SUBJECTS: 1333 men resident in Uppsala, Sweden, who took part in a 1970 study of coronary risk factors at age 50 and for whom birth weight was traced. MAIN OUTCOME MEASURES: Systolic and diastolic blood pressure at age 50. RESULTS: In the full study population for a 1000g increase in birth weight there was a small change in systolic blood pressure of -2.2mmHg (95% confidence interval -4.2 to - 0.3mmHg) and in diastolic blood pressure of -1.0mmHg (-2.2 to 0.1mmHg). Much stronger effects were observed among men who were born at term and were in the top third of body mass index at age 50, for whom a 1000g increase in birth weight was associated with a change of -9.1mmHg (-16.4 to-1.9mmHg) systolic and -4.2mmHg (-8.3 to -0.1mmHg) diastolic blood pressure. Men who were light at birth (<3250g) but were above median adult height had particularly high blood pressure. Adjustment for insulin concentrations reduced the associations of birth weight with systolic and diastolic blood pressure. CONCLUSIONS: A failure to realise growth potential in utero (as indicated by being light at birth but tall as an adult) is associated with raised adult blood pressure. Impaired fetal growth may lead to substantial increases in adult blood pressure among only those who become obese. Metabolic disturbances, possibly related to insulin resistance, may provide a pathway through which fetal growth affects blood pressure.  相似文献   

19.
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.  相似文献   

20.
OBJECTIVE--To examine whether cardiovascular risk factors differ in children from towns in England and Wales with widely differing adult cardiovascular death rates. DESIGN--School based survey conducted during 1994 in 10 towns, five with exceptionally high adult cardiovascular mortality (standardised mortality ratio 131-143) and five with exceptionally low adult cardiovascular mortality (64-75). Towns were surveyed in high-low pairs. SUBJECTS--3415 white children aged 8-11 years with physical measurements (response rate 75%), including 1287 with blood samples (response rate 64%), of whom 515 had blood samples taken 30 minutes after a glucose load. RESULTS--Children in towns with high cardiovascular mortality were on average shorter than those in towns with low mortality (mean difference 1.2 cm; 95% confidence interval 0.3 to 2.1 cm; P = 0.02) and had a higher ponderal index (0.34 kg/m3; 0.16 to 0.52 kg/m3; P = 0.006). Mean systolic pressure was higher in high mortality towns, particularly after adjustment for height (2.0 mm Hg; 0.8 to 3.2 mm Hg; P = 0.009). Mean waist:hip ratio, total cholesterol concentration, and 30 minute post-load glucose measurements were similar in high and low mortality towns. The differences in height and blood pressure between high and low mortality towns were unaffected by standardisation for birth weight. CONCLUSIONS--The differences in height, ponderal index, and blood pressure between towns with high and low cardiovascular mortality, if persistent, may have important future public health implications. Their independence of birth weight suggests that the childhood environment rather than the intrauterine environment is involved in their development.  相似文献   

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