PubMed Health⌕ Search

Biomedical subjects

O Papacosta

Publications and source records attributed to O Papacosta.

26 records · Page 2Linked to original sources

Passive exposure to tobacco smoke in children aged 5-7 years: individual, family, and community factors.

OBJECTIVE: To examine the importance of parental smoking on passive exposure to tobacco smoke in children and the social and geographical patterns of exposure. DESIGN: Cross sectional study. SETTING: Schools in 10 towns in England and Wales; five towns with high adult cardiovascular mortality and five with low rates. SUBJECTS: 4043 children aged 5-7 years of European origin. MAIN OUTCOME MEASURES: Salivary cotinine concentration and parents self reported smoking habits. RESULTS: 1061 (53.0%) children were exposed to cigarette smoke at home or by an outside carer. Geometric mean cotinine rose from 0.29 (95% confidence interval 0.28 to 0.31) ng/ml in children with no identified exposure to 4.05 (3.71 to 4.42) ng/ml in households where both parents smoked and 9.03 (6.73 to 12.10) ng/ml if both parents smoked more than 20 cigarettes a day. The effect of mothers' smoking was greater than that of fathers', especially at high levels of consumption. After adjustment for known exposures geometric mean cotinine concentrations rose from 0.52 ng/ml in social class I to 1.36 ng/ml in social class V (P < 0.0001); and were doubled in high mortality towns compared with the low mortality towns (P = 0.002). In children with no identified exposure similar trends by social class and town were observed and the cotinine concentrations correlated with the prevalence of parental smoking, both between towns (r = 0.69, P = 0.02) and between schools within towns (r = 0.50, P < 0.001). CONCLUSIONS: Mothers' smoking is more important that fathers' despite the lower levels of smoking by mothers. Children not exposed at home had low cotinine concentration, the level depending on the prevalence of smoking in the community.

Age Factors↗

Maternal factors and development of cardiovascular risk: evidence from a study of blood pressure in children.

It has been suggested that risks of hypertension and cardiovascular disease begin in utero and that maternal nutrition plays an important role. We have examined the relation between maternal factors and BP in a study of 1,311 children in which physical measurements at 9-11 years of age have been linked to a parental questionnaire; birth record data were also available in a subsample of 662 children. Maternal height was inversely related to childhood BP after adjustment for the child's current height. However, several social factors related to maternal nutrition in pregnancy in earlier studies (including social class, housing tenure, maternal educational attainment and maternal smoking in pregnancy) showed weak and inconsistent relations with BP at 9-11 years. Minimum maternal haemoglobin in pregnancy and change in mean corpuscular volume in pregnancy (identified as potentially important markers of maternal nutrition in earlier studies) showed no consistent relationships either with placental weight to birthweight ratio or with childhood BP, although both factors showed strong inverse associations with birthweight. The association between maternal height and childhood BP may reflect the influence of early life factors on cardiovascular risk. However, the absence of consistent relationships between social factors and BP in offspring provides little support for the possibility that maternal diet is an important influence on cardiovascular risk factors in childhood. Minimum maternal haemoglobin and change in maternal mean corpuscular volume are unlikely to be specific markers of maternal nutrition in pregnancy. More specific hypotheses relating maternal nutrition to the development of cardiovascular risk in offspring are required.

Adult↗

Time trends in respiratory symptoms in childhood over a 24 year period.

Two cross sectional surveys, 24 years apart, using the same respiratory questionnaire, were carried out to examine changes in prevalence rates of cough, phlegm, and wheeze and to relate changes in wheeze to objective peak expiratory flow rates (PEFRs). The surveys were done in towns in southern and northern England and South Wales in schoolchildren aged 6.0-7.5 years; n = 1655 in 1966 and n = 2323 in 1990. Parents reported on winter cough and winter phlegm (early morning or day/night) and wheeze; PEFRs were also measured. The proportion of children reported as wheezing on most days or nights increased from 3.9% to 6.1% (95% confidence interval (CI) for increase -0.2 to 4.6), with a smaller increase in the prevalence of those who had ever wheezed. The proportion of children with day or night time cough increased from 21.1% to 33.3% (95% CI for increase 3.8 to 20.6) and the proportion with day or night time phlegm increased from 5.8% to 10.0% (95% CI for increase 0.4 to 8.0). Smaller increases in the prevalence of persistent cough (from 9.0% to 12.4%) and persistent phlegm (from 2.4% to 3.5%) were also observed, while morning cough and morning phlegm showed little change. The increases in cough and phlegm were apparent in subjects with and without a history of wheeze. Both absolute and proportional changes in symptom prevalence were generally greater in the north than in the south. Similar social class trends were seen in each survey. The mean difference in PEFR between subjects with and without wheeze was smaller in 1990 than in 1966, but this result could be influenced by a greater proportion of subjects receiving antiasthmatic treatment in the 1990 survey. These apparent increases in the prevalence of persistent wheeze, day and night time cough and phlegm, occurring over a period during which outdoor air pollution levels have decreased substantially, deserve further investigation.

Child↗

Relation of passive smoking as assessed by salivary cotinine concentration and questionnaire to spirometric indices in children.

BACKGROUND: Previous studies of the effects of passive exposure to smoke on spirometric indices in children have largely relied on questionnaire measures of exposure. This may have resulted in underestimation of the true effect of passive smoking. Biochemical measures offer the opportunity to estimate recent exposure directly. METHODS: The relation between spirometric indices and passive exposure to tobacco smoke was examined in a large population sample of 5-7 year old children from 10 towns in England and Wales. The effects of passive exposure to smoke on lung function were assessed by means of both salivary cotinine concentration and questionnaire measurements of exposure. Analyses of the relation between spirometric values and cotinine concentrations were based on 2511 children and of the relation between spirometric values and questionnaire measures on 2000 children. RESULTS: Cotinine concentration was negatively associated with all spirometric indices after adjustment for confounding variables, which included age, sex, body size, and social class. The strongest association was with mid expiratory flow rate (FEF50), the fall between the bottom and top fifths of the cotinine distribution being 6%, equivalent to a reduction of 14.3 (95% confidence limits (CL) 8.6, 20.0) ml/s per ng/ml cotinine. Salivary cotinine concentrations were strongly related to exposure to cigarette smoke at home but 88% of children who were from non-smoking households and not looked after by a smoker had detectable cotinine concentrations, 5% being in the top two fifths of the cotinine distribution. A composite questionnaire score based on the number of regular sources of exposure was as strongly related to mid and end expiratory flow rates as the single cotinine measure. The fall in FEF50 per smoker to whom the child was exposed was 51.0 (26.5, 75.5) ml/s. The relationships between the questionnaire score and forced vital capacity (FVC) or forced expiratory volume in one second (FEV1) were not statistically significant. CONCLUSIONS: These effects of passive smoking on respiratory function are consistent with the results of previous studies and, although small in absolute magnitude, may be important if the effects of exposure are cumulative. In children aged 5-7 years the use of a single salivary cotinine concentration as a marker of passive exposure to smoke resulted in clear relationships between exposure and FVC and FEV1, whereas the associations were much weaker and not significant when based on the questionnaire score. The associations between exposure and mid or end expiratory flow rates were of similar magnitude for cotinine concentration and the questionnaire score. The use of salivary cotinine concentration in longitudinal studies may help to determine the extent to which these effects are cumulative or reversible.

Biomarkers↗

Do maternal and intrauterine factors influence blood pressure in childhood?

It has been proposed that maternal health and nutrition may be important in the development of adult cardiovascular risk, and that blood pressure may be an important intermediate step in this process. To examine the relevance of this hypothesis in contemporary British children, the relationships of several maternal factors to blood pressure were studied in 3360 children of European origin aged 5-7 years. Maternal age, height, and body mass index were all positively related to blood pressure in childhood but these relationships were abolished once the child's body build was taken into account. Maternal social class, educational attainment, and history of smoking in pregnancy showed no relationship with blood pressure in childhood. Parity showed an inverse association with blood pressure, but this appeared to be due to an association between total sibship size and blood pressure, suggesting a postnatal rather than a prenatal origin. Blood pressure was higher in children whose mothers had a history of high blood pressure but this association was no stronger than that for paternal history. Both birth weight and gestational age were inversely related to blood pressure at 5-7 years. The association between birth weight and blood pressure was attenuated by standardisation for gestational age, and the relationships between birth weight and blood pressure were similar in preterm and full term infants. No specific association between blood pressure and the maternal factors studied have been observed in this population. Hypotheses relating maternal factors to cardiovascular risk need to specify the timing and nature of their effects more precisely. Although the relationship between birth weight and blood pressure is not fully understood, it appears to reflect size at birth rather than fetal growth rate.

Birth Weight↗

Childhood blood pressure, body build, and birthweight: geographical associations with cardiovascular mortality.

STUDY OBJECTIVE: The aim was to examine whether blood pressure, body build, and birthweight differ between areas of England and Wales with widely differing adult cardiovascular mortality rates. DESIGN: This was a cross sectional survey of children in five towns with exceptionally high and five towns with exceptionally low current adult cardiovascular mortality. SETTING: The study was a school based survey. SUBJECTS: 3842 children aged 5.0-7.5 years were selected by stratified random sampling of primary schools (response rate 76%). MEASUREMENTS AND MAIN RESULTS: Blood pressure, pulse rate, height, and weight were measured and birthweight was assessed by maternal recall. Children in towns with high cardiovascular mortality rates were significantly shorter than those in towns with low cardiovascular mortality rates (mean difference 0.9 cm, 95% confidence interval 0.4 to 1.4 cm) and had slightly higher body mass indices (mean difference 0.12 kg/m2, 95% CI -0.03 to 0.27 kg/m2). Mean birthweights were slightly lower in high mortality towns (mean difference 34 g, 95% CI -10 to 78 g), while the proportion of children with low birthweight (< 2500 g) (8.1%) was significantly higher than that in low mortality towns (5.5%) (p = 0.005). Mean differences in blood pressure between high and low mortality towns were small and non-significant, even after adjustment for height. The differences in height between high and low mortality towns were largely independent of social class. However, differences in mean birthweight were markedly reduced once social class was taken into account. CONCLUSIONS: No geographical relationship between childhood blood pressure and adult cardiovascular mortality was detected. Although it is possible that the differences in mean height and body mass index between towns with differing adult cardiovascular mortality may have implications for future patterns of health in these towns, the absence of marked differences in birthweight and blood pressure suggests that hypotheses proposing a direct relationship between intrauterine experience and adult cardiovascular mortality will have limited relevance to geographical variation in cardiovascular disease in this generation.

Adult↗