Search PubMed⌕ Search

Biomedical subjects

C Osmond

Publications and source records attributed to C Osmond.

At least 55 records · Page 3Linked to original sources

Effects of infant birthweight and maternal body mass index in pregnancy on components of the insulin resistance syndrome in China.

BACKGROUND: Reduced birthweight is associated with increased risk for the insulin resistance syndrome. Part of this risk is hypothesized to originate from undernutrition in utero. The prevalence of the insulin resistance syndrome increases in countries that undergo the transition from chronic malnutrition to adequate nutrition, when postnatal nutrition improves more rapidly than prenatal nutrition. OBJECTIVE: To determine whether the components of the insulin resistance syndrome are associated with reduced fetal growth and maternal undernutrition. DESIGN: A nonconcurrent, prospective study of men and women whose mothers' heights and weights were recorded during pregnancy. SETTING: Beijing, China. PARTICIPANTS: 627 men and women (mean age, 45 years) whose mothers' obstetric records were preserved. MEASUREMENTS: Adult offspring's blood pressure, plasma glucose levels, insulin levels, and lipid concentrations during an oral glucose tolerance test. The main explanatory measurements were mothers' body mass index during pregnancy and offspring's birthweight and adult size. RESULTS: After adjustment for sex and current body mass index, low birthweight was associated with elevated plasma glucose levels, insulin levels, triglyceride concentrations, and blood pressure. For every 1-kg increase in birthweight, systolic blood pressure decreased by 2.9 mm Hg (95% CI, 0.3 to 5.4 mm Hg) and the 2-hour plasma glucose level decreased by 5.1% (CI, 0.7% to 9.3%). Low maternal body mass index in early and late pregnancy was associated with elevated levels of plasma glucose, insulin, and triglycerides in adult offspring but was not associated with elevated blood pressure. CONCLUSIONS: Risk for the insulin resistance syndrome may be partially established through low maternal body mass before pregnancy and consequent fetal undernutrition. This risk is independent of that associated with adult obesity. In developing countries such as China, improved nutrition in girls and young women may offer long-term benefits to offspring.

Adult↗

Trends in epilepsy mortality in England and Wales and the United States, 1950-1994.

The aim of this study was to analyze time trends in epilepsy mortality in England and Wales and the United States between 1950 and 1994. The authors calculated age- and sex-specific epilepsy mortality rates for the nine quinquennia from 1950-1954 to 1990-1994. Mortality rates were modeled as a function of age, period of death, and cohort of birth by using Poisson regression techniques. From 1950 to 1994, there were more than 110,000 deaths from epilepsy in the two countries. The secular trends in mortality were similar for both sexes and in both countries. Among people younger than age 20 years, epilepsy mortality declined steeply after 1950. For young and middle-aged adults, the rate of decline was lower. In the geriatric population, mortality declined between 1950 and 1974 but then increased. The Poisson model showed pronounced birth cohort effects. In the United States, epilepsy mortality fell with each successive birth cohort after 1905. In England and Wales, there was a similar decline in birth cohort mortality after 1905 for women but not until after 1950 for men. The pronounced birth cohort effect supports explanations that focus on antenatal and developmental factors as the cause for the decline in epilepsy mortality in all but the oldest age groups between 1950 and 1994.

Adolescent↗

Plasma fibrinogen and factor VII concentrations in adults after prenatal exposure to famine.

To assess the effect of maternal malnutrition during different stages of gestation on plasma concentrations of fibrinogen and factor VII, we investigated 725 people, aged 50 years, born around the time of the Dutch famine 1944-5. After adjustment for sex, plasma fibrinogen concentrations differed by -0.01 g/l (95% confidence interval, -0.14-0.11) in those exposed in late gestation, by -0.03 g/l (-0.16-0.11) in those exposed in mid gestation, and by 0.13 g/l (-0.03-0.30) in those exposed in early gestation, compared with non-exposed people (those born before and those conceived after the famine pooled together). Plasma factor VII concentrations differed by 0.4% (-5.4% to 6.6%) in those exposed to famine in late gestation, by 1.5% (-4.6% to 8.1%) in those exposed in mid gestation. and by -11.8% (-18.4 to -4.8%) in those exposed in early gestation, compared with nonexposed people. Size at birth was not associated with plasma concentrations of fibrinogen or factor VII. Our finding that factor VII concentrations were significantly lower in people whose mothers had been exposed to famine in early pregnancy suggests that liver function may be affected by undernutrition in early gestation.

Birth Weight↗

Plasma lipid profiles in adults after prenatal exposure to the Dutch famine.

BACKGROUND: Small body size at birth has been reported to be associated with an atherogenic lipid profile in humans, and animal experiments have shown that undernutrition during pregnancy permanently alters cholesterol metabolism in the offspring. There is no direct evidence in humans that maternal malnutrition during pregnancy affects the lipid profiles of the offspring. OBJECTIVES: We assessed the effects of maternal malnutrition during specific periods of gestation on plasma lipid profiles in persons aged approximately 50 y. DESIGN: This was a follow-up study of men and women born at term as singletons in a university hospital in Amsterdam between 1 November 1943 and 28 February 1947 around the time of a severe famine. RESULTS: Persons exposed to famine in early gestation had a more atherogenic lipid profile than did those who were not exposed to famine in utero. Their LDL-HDL cholesterol ratios were significantly higher (by 13.9%; 95% CI: 2.6-26.4%). Additionally, their plasma HDL-cholesterol and apolipoprotein A concentrations tended to be lower, and their plasma total cholesterol, LDL-cholesterol, and apolipoprotein B concentrations tended to be higher, although these differences were not statistically significant. The effect of famine was independent of size at birth and adult obesity. CONCLUSIONS: An atherogenic lipid profile might be linked to a transition from poor maternal nutrition in early gestation to adequate nutrition later on. This suggests that maternal malnutrition during early gestation may program lipid metabolism without affecting size at birth.

Apolipoproteins A↗

Comparative effects of laser and radiofrequency energy on joint capsule.

The study compared the effects of laser and monopolar radiofrequency energy on thermal and architectural properties of joint capsular tissue in an in vitro ovine model. Sheep glenohumeral joint capsular specimens were treated with laser (5, 10, 15 W) or radiofrequency energy (55 degrees, 65 degrees, 75 degrees C) (n = six per group). Energy application caused significant tissue shrinkage and decreased surface area in all laser and radiofrequency treatment groups. Tissue thickness significantly increased in all treatment groups except for radiofrequency 55 degrees C. Tissue shrinkage, surface area, and thickness each correlated significantly with the delivered laser energy per tissue area or mean radiofrequency probe temperature. There were no significant differences among laser 10 W, laser 15 W, and radiofrequency 75 degrees C treatment groups for these three architectural parameters. Tissue temperature was elevated significantly in the laser 10 W, laser 15 W, radiofrequency 65 degrees C, and radiofrequency 75 degrees C groups when compared with the control. Tissue temperature changes between the laser 10 W and radiofrequency 75 degrees C groups were similar; however, laser treatment produced a steeper temperature increase accompanying its peak temperature. Despite different mechanisms, laser and radiofrequency energy can achieve similar and predictable tissue modification, which is temperature dependent. Additional in vivo studies must be performed to evaluate the applicability of these techniques to clinical use.

Animals↗

Infant feeding and adult glucose tolerance, lipid profile, blood pressure, and obesity.

BACKGROUND: It is generally accepted that breast feeding has a beneficial effect on the health of infants and young children. Recently, a few studies have shown that the method of infant feeding is also associated with cardiovascular disease and its risk factors in adult life. AIMS: To examine the association between the method of infant feeding in the first weeks after birth and glucose tolerance, plasma lipid profile, blood pressure, and body mass in adults aged 48-53 years. METHODS: Subjects born at term between 1 November 1943 and 28 February 1947 in the Wilhelmina Gasthuis in Amsterdam around the time of a severe period of famine (late November 1944 to early May 1945). For 625 subjects, information was available about infant feeding at the time of discharge from hospital (on average 10.4 days after birth), and at least one blood sample after an overnight fast. RESULTS: Subjects who were bottle fed had a higher mean 120 minute plasma glucose concentration after a standard oral glucose tolerance test than those who were exclusively breast fed. They also had a higher plasma low density lipoprotein (LDL) cholesterol concentration, a lower high density lipoprotein (HDL) cholesterol concentration, and a higher LDL/HDL ratio. Systolic blood pressure and body mass index were not affected by the method of infant feeding. CONCLUSIONS: Exclusive breast feeding seems to have a protective effect against some risk factors for cardiovascular disease in later life.

Adolescent↗

Coronary heart disease after prenatal exposure to the Dutch famine, 1944-45.

OBJECTIVE: To assess the effect of prenatal exposure to maternal malnutrition on coronary heart disease in people born around the time of the Dutch famine, 1944-45. DESIGN: Historical cohort study. SETTING: Community study. PATIENTS: Singletons born alive between November 1943 and February 1947 for whom detailed birth records were available. DESIGN: The prevalence of coronary heart disease was compared between those exposed to famine in late gestation (n = 120), in mid-gestation (n = 108), or in early gestation (n = 68), and those born in the year before the famine or those conceived in the year after the famine (non-exposed subjects, n = 440). MAIN OUTCOME MEASURES: Prevalence of coronary heart disease, defined as the presence of angina pectoris according to the Rose questionnaire, Q waves on the ECG, or a history of coronary revascularisation. RESULTS: The prevalence of coronary heart disease was higher in those exposed in early gestation than in non-exposed people (8.8% v 3.2%; odds ratio adjusted for sex 3.0, 95% confidence interval (CI) 1.1 to 8.1). The prevalence was not increased in those exposed in mid gestation (0.9%) or late gestation (2.5%). People with coronary heart disease tended to have lower birth weights (3215 g v 3352 g, p = 0.13), and smaller head circumferences at birth (32.2 cm v 32.8 cm, p = 0.05), but the effect of exposure to famine in early gestation was independent of birth weight (adjusted odds ratio 3.2, 95% CI 1.2 to 8.8). CONCLUSIONS: Although the numbers are very small, this is the first evidence suggesting that maternal malnutrition during early gestation contributes to the occurrence of coronary heart disease in the offspring.

Birth Weight↗

Atopy, lung function, and obstructive airways disease after prenatal exposure to famine.

BACKGROUND: Associations have been found between a large head size at birth and atopy, and between low birth weight and obstructive airways disease. A study was undertaken of people born around the time of the Dutch famine in 1944-5 to determine the effects of maternal malnutrition during specific periods of gestation on the prevalence of obstructive airways disease and atopy. METHODS: Nine hundred and twelve people aged about 50, born at term between November 1943 and February 1947 in Amsterdam, were asked about their medical history. Lung function was measured in 733 and serum concentrations of total IgE and specific IgE against mite, pollen and cat were measured in 726. Those exposed in late, mid, and early gestation (exposed participants) were compared with those born before or conceived after the famine (non-exposed participants). RESULTS: Exposure to famine during gestation affected neither the concentrations of total or specific IgE nor lung function values. The prevalence of obstructive airways disease was increased in people exposed to famine in mid gestation (odds ratio adjusted for sex 1.7, 95% confidence interval (CI) 1.1 to 2.6) and tended to be higher in those exposed in early gestation (odds ratio 1.5, 95% CI 0. 9 to 2.6). CONCLUSIONS: The observed increase in the prevalence of obstructive airways disease in people exposed to famine in mid and early gestation was not parallelled by effects on IgE concentrations or lung function. The link between exposure to famine in mid and early gestation and obstructive airways disease in adulthood suggests that fetal lungs can be permanently affected by nutritional challenges during periods of rapid growth.

Birth Weight↗

Blood pressure is related to placental volume and birth weight.

The objective of this study was to determine whether maternal nutrition and fetal and placental size program blood pressure. A longitudinal study linking the maternal anthropometric measurements of the first antenatal visit, ultrasound data of placental and fetal size, anthropometry at birth, and childhood growth and blood pressure was performed. The subjects were 428 women who attended the antenatal clinic at the University Hospital of the West Indies, Kingston, Jamaica, and their children, who were subsequently followed up. Systolic blood pressure at ages 1, 2, 2.5, 3, and 3.5 years was the main outcome measure. Pooling the data across ages, systolic blood pressure fell by 1.4 mm Hg for every 1-kg increase in birth weight (95% CI 0.2 to 2.7, P=0.02) and by 1.2 mm Hg for every 100-mL increase in placental volume at 20 weeks of gestation (95% CI 0.4 to 2.0, P=0.004). Blood pressure was also negatively associated with placental volume at 17 weeks and fetal abdominal circumference at 20 weeks. Measures of maternal nutritional status were strongly related to birth weight and placental volume but not directly to childhood blood pressure at these young ages. In conclusion, blood pressure is associated with fetal size in this population, as previously described among Europeans. We found associations between placental volume and abdominal circumference in the second trimester and childhood blood pressure, suggesting that the initiating events of blood pressure programming occur early in pregnancy. Measures of maternal nutritional status were not directly related to childhood blood pressure at these young ages but were strong predictors of both birth weight and placental volume, suggesting an indirect relation.

Adolescent↗

Low birth weight predicts elevated plasma cortisol concentrations in adults from 3 populations.

Low birth weight is linked with raised blood pressure in adult life. Recent evidence has suggested that a neuroendocrine disturbance involving the hypothalamic-pituitary-adrenal axis could mediate this link. We therefore investigated the relation between birth weight and fasting plasma cortisol concentrations and the association of cortisol with current blood pressure in population samples of 165 men and women born in Adelaide, South Australia, from 1975 to 1976, 199 men and women born in Preston, UK, from 1935 to 1943, and 306 women born in East Hertfordshire, UK, from 1923 to 1930. Fasting plasma cortisol was measured in plasma samples obtained between 8 and 10 AM. Blood pressure was measured with an automated sphygmomanometer. Low birth weight was associated with raised fasting plasma cortisol concentrations in all 3 populations. A combined analysis that allowed for differences in the gender composition, age, and body mass index between the studies showed that cortisol concentrations fell by 23.9 nmol/L per kilogram increase in birth weight (95% CI 9.6 to 38.2, P<0.001). Fasting plasma cortisol concentrations also correlated positively with the subjects' current blood pressure. However, the association between cortisol and blood pressure was most marked in subjects who were obese (P=0.038 for interaction between body mass index and cortisol, P=0.01 for interaction between waist-to-hip ratio and cortisol). These results show that low birth weight is associated with raised fasting plasma cortisol concentrations. Increased activity of the hypothalamic-pituitary-adrenal axis may link low birth weight with raised blood pressure in adult life.

Adult↗

Fetal and childhood growth and hypertension in adult life.

The association between low birth weight and raised blood pressure has been extensively replicated. Little is known about the way childhood growth modifies the effects of low birth weight. We report on the fetal and childhood growth of 1958 men and women who received treatment for hypertension and belong to a cohort of 7086 people born in Helsinki, Finland, during 1924-1933. As expected, the men and women who developed hypertension had low birth weight (P=0.002). They were also shorter in body length at birth (P=0.02). After birth they experienced accelerated growth, so that by 7 years their heights and weights were approximately average. In a simultaneous regression, both birth length and tall height had statistically significant although opposing effects on hypertension (P=0.003 for birth length and 0.009 for height at 7 years). Accelerated postnatal growth was associated with better childhood living conditions. Children who later developed both hypertension and type 2 diabetes, rather than hypertension alone, had small placental size as well as small body size at birth, and their accelerated postnatal growth continued beyond 7 years. We suggest that hypertension may originate through retarded growth in utero followed by accelerated postnatal growth as a result of good living conditions. Retarded fetal growth leads to permanently reduced cell numbers in the kidney and other tissues, and subsequent accelerated growth may lead to excessive metabolic demand on this limited cell mass.

Adolescent↗

Fetal growth and early postnatal growth are related to blood pressure in adults.

It is commonly agreed that birth weight is associated with blood pressure in adults. However, not much is known about birth length, ponderal index, and early postnatal growth, whose effects on adult blood pressure, if any, can affect the interpretation of the birth weight-blood pressure association. This study examined the association between fetal growth, early postnatal growth, and blood pressure in Chinese adults. One hundred twenty-two subjects born in Hong Kong in 1967 were followed from birth to age 30 years. Multiple linear regression was used to analyze the association between size at birth, postnatal changes in body size, and systolic and diastolic blood pressure at age 30 years. Having adjusted for potential confounders and each other explanatory variable, it is found that birth length standard deviation score (regression coefficient or beta=-3.2), ponderal index at birth (beta=-1.8), and postnatal changes in ponderal index from age 6 months to 18 months (beta=-2.2) were inversely associated with systolic blood pressure (each P<0.05). Postnatal changes in length standard deviation score were not significantly associated with systolic blood pressure. Birth length standard deviation score was inversely associated with diastolic blood pressure at age 30 years (beta=-2.6; P<0.05). Other anthropometric variables were not associated with diastolic blood pressure. The results support the hypotheses that both fetal growth and early postnatal growth may have a long-term impact on blood pressure in adults. It also highlights the importance of differentiating length and weight for length.

Adolescent↗

Early growth, adult income, and risk of stroke.

BACKGROUND AND PURPOSE: A number of studies have shown that reduced intrauterine growth and low birth weight are associated with raised rates of fatal and nonfatal stroke in adult life. Whether this increased risk of stroke is modified by growth in childhood or by socioeconomic status in adult life is not known. METHODS: We studied hospital admissions and deaths from stroke among 3639 men who were born in Helsinki University Central Hospital during 1924 to 1933. They had detailed records of their body size at birth, their growth through childhood, and their social circumstances as adults. Three hundred thirty-one of the men had had a stroke. RESULTS: Hazard ratios for stroke were related to low birth weight in relation to head circumference (P=0.005) and to short length in relation to head circumference (P=0.02). These associations were stronger for hemorrhagic than for thrombotic stroke. Men who developed stroke still had below-average stature at 7 years (P=0.05), but after 7 years their height "caught up" through accelerated growth. As adults they had low incomes and low social class (P<0.0001). CONCLUSIONS: Stroke may originate through reduced fetal growth, with low body weight and short body length at birth but "sparing" of head growth. Other studies suggest that this pattern of growth is associated with persisting elevation of blood pressure and raised plasma fibrinogen concentrations, 2 known risk factors for stroke. The risk of stroke is increased by accelerated growth in height during childhood. Accelerated growth has previously been linked to the development of hypertension in adult life. Stroke risk is further increased by adverse influences linked to low income.

Aged↗

Fetal, infant, and childhood growth are predictors of coronary heart disease, diabetes, and hypertension in adult men and women.

Many human fetuses have to adapt to a limited supply of nutrients. In doing so they permanently change their structure and metabolism. These programmed changes may be the origins of a number of diseases in later life, including coronary heart disease, hypertension, and noninsulin- dependent diabetes. We review epidemiologic studies in which the incidence of these diseases has been related to the recorded, early growth of individuals, while considering factors in the adult lifestyle, such as obesity and socioeconomic status. We discuss possible mechanisms. For hypertension these mechanisms include placentation, maternal blood pressure, fetal undernutrition; childhood growth, activation of the renin-angiotensin system, renal structure, programming of the hypothalamic-pituitary-adrenal axis, vascular structure, and sympathetic nervous activity. For noninsulin-dependent diabetes we discuss mechanisms concerning both insulin resistance and insulin deficiency. We include a review of evidence for the programming of serum cholesterol and clotting factor concentrations. We address the timing of critical windows for coronary heart disease, reviewing studies that allow assessment of the relative importance of fetal, infant, and childhood growth. We argue for a research strategy that combines clinical, animal, and epidemiological studies.

Adolescent↗

Workshop to identify critical windows of exposure for children's health: cardiovascular and endocrine work group summary.

The work group on cardiovascular and endocrine effects was asked to review the current state of knowledge about children's windows of vulnerability to developmental toxicants and to recommend how that information may be used to improve risk assessment and public health. We considered differences between structural defects, where periods of vulnerability are rather well defined, and functional defects, where periods of vulnerability are quite elusive.

Cardiovascular System↗

Growth in utero and during childhood among women who develop coronary heart disease: longitudinal study.

OBJECTIVE: To examine whether women who develop coronary heart disease have different patterns of fetal and childhood growth from men in the same cohort who develop the disease. DESIGN: Follow up study of women whose body size at birth was recorded and who had an average of 10 measurements of height and weight during childhood. SETTING: Helsinki, Finland. SUBJECTS: 3447 women who were born in Helsinki University Central Hospital during 1924-33 and who went to school in Helsinki. MAIN OUTCOME MEASURES: Hazard ratios for hospital admission for or death from coronary heart disease. Results Coronary heart disease among women was associated with low birth weight (P=0.08 after adjustment for gestation, P=0.007 after adjustment for placental weight) and was more strongly associated with short body length at birth (P=0.001 and P<0.0001, respectively). The hazard ratio for women developing coronary heart disease increased by 10.2% (95% confidence interval 4.3 to 15.7) for each cm decrease in length at birth. The effect of short length at birth was greatest in women whose height "caught up" after birth so that as girls they were tall. Such girls tended to have tall mothers. In contrast, men in the same cohort who developed the disease were thin at birth rather than short, showed "catch up" growth in weight rather than height, and their mothers tended to be overweight rather than tall. CONCLUSION: Coronary heart disease among both women and men reflects poor prenatal nutrition and consequent small body size at birth combined with improved postnatal nutrition and "catch up" growth in childhood. The disease is associated with reductions in those aspects of body proportions at birth that distinguish the two sexes-short body length in women and thinness in men.

Adolescent↗

Catch-up growth in childhood and death from coronary heart disease: longitudinal study.

OBJECTIVE: To examine whether catch-up growth during childhood modifies the increased risk of death from coronary heart disease that is associated with reduced intrauterine growth. DESIGN: Follow up study of men whose body size at birth was recorded and who had an average of 10 measurements taken of their height and weight through childhood. SETTING: Helsinki, Finland. SUBJECTS: 3641 men who were born in Helsinki University Central Hospital during 1924-33 and who went to school in Helsinki. MAIN OUTCOME MEASURES: Hazard ratios for death from coronary heart disease. RESULTS: Death from coronary heart disease was associated with low birth weight and, more strongly, with a low ponderal index at birth. Men who died from coronary heart disease had an above average body mass index at all ages from 7 to 15 years. In a simultaneous regression the hazard ratio for death from the disease increased by 14% (95% confidence interval 8% to 19%; P<0.0001) for each unit (kg/m3) decrease in ponderal index at birth and by 22% (10% to 36%; P=0.0001) for each unit (kg/m2) increase in body mass index at 11 years of age. Body mass index in childhood was strongly related to maternal body mass index, which in turn was related to coronary heart disease. The extent of crowding in the home during childhood, although related to body mass index in childhood, was not related to later coronary heart disease. CONCLUSION: The highest death rates from coronary heart disease occurred in boys who were thin at birth but whose weight caught up so that they had an average or above average body mass from the age of 7 years. Death from coronary heart disease may be a consequence of poor prenatal nutrition followed by improved postnatal nutrition.

Adolescent↗