Smoking in pregnancy is a key factor for sudden infant death among Maori.

AIM: To examine the sudden unexpected death in infancy (SUDI) disparity between Maori and non-Maori in New Zealand. METHODS: A nationwide prospective case-control study ran from March 2012 to February 2015. Exposure to established SUDI risk factors was analysed to investigate the disparity experienced by Maori. Infant ethnicity was based on mother's ethnicity. Maori ethnicity was prioritised. Non-Maori includes Pacific, Asian, NZ European and Other. RESULTS: There were 137 cases and 649 controls. The Maori SUDI rate was 1.41/1000 live births compared to 0.53/1000 for non-Maori. Parents/caregivers of 132 cases (96%) and 258 controls (40%) were interviewed. Smoking in pregnancy was associated with an equally increased SUDI risk for Maori (adjusted OR = 8.11, 95% CI = 2.64, 24.93) and non-Maori (aOR = 5.09, 95% CI = 1.79, 14.47), as was bed-sharing (aOR = 3.66, 95% CI = 1.49, 9.00 vs aOR = 11.20, 95% CI = 3.46, 36.29). Bed-sharing prevalence was similar; however, more Maori controls smoked during pregnancy (46.7%) than non-Maori (22.8%). The main contributor relating to increased SUDI risk for Maori/non-Maori infants is the combination of smoking in pregnancy and bed sharing. CONCLUSION: The association between known SUDI risk factors, including bed sharing and/or smoking in pregnancy and SUDI risk, is the same regardless of ethnicity. Maori infants are exposed more frequently to both behaviours because of the higher Maori smoking rate.

Age-related prevalence of cross-reactive antibodies against influenza A(H3N2) variant virus, Germany, 2003 to 2010.

To estimate susceptibility to the swine-origin influenza A(H3N2) variant virus (A(H3N2)v) in the German population, we investigated cross-reactive antibodies against this virus and factors associated with seroprotective titre using sera from representative health examination surveys of children and adolescents (n = 815, 2003­06) and adults (n = 600, 2008­10). Antibodies were assessed by haemagglutination inhibition assay (HI); in our study an HI titre ≥ 40 was defined as seroprotective. We investigated associated factors by multivariable logistic regression. Overall, 41% (95% confidence interval (CI): 37­45) of children and adolescents and 39% (95% CI: 34­44) of adults had seroprotective titres. The proportion of people with seroprotective titre was lowest among children younger than 10 years (15%; 95% CI: 7­30) and highest among adults aged 18 to 29 years (59%; 95% CI: 49­67). Prior influenza vaccination was associated with higher odds of having seroprotective titre (odds ratio (OR) for children and adolescents: 3.4; 95% CI: 1.8­6.5; OR for adults: 2.4; 95% CI: 1.7­3.4). Young children showed the highest and young adults the lowest susceptibility to the A(H3N2)v virus. Our results suggest that initial exposure to circulating seasonal influenza viruses may predict long-term cross-reactivity that may be enhanced by seasonal influenza vaccination.

[Prevalence of common allergies in children and adolescents in Germany: results of the KiGGS study: first follow-up (KiGGS Wave 1)]. / Verbreitung häufiger Allergien bei Kindern und Jugendlichen in Deutschland : Ergebnisse der KiGGS-Studie - Erste Folgebefragung (KiGGS Welle 1).

The first follow-up of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS Wave 1) was conducted from 2009 to 2012 as a combined cross-sectional and longitudinal study and provides, among other things, data on allergic diseases. Data collection was carried out by telephone interviews. In total, 6,093 girls and 6,275 boys were included, among them 4,455 newly recruited 0- to 6-year-olds (response 38.8%) and 7,913 KiGGS follow-up participants aged 7-17 years (response 72.9%). Based on parent reports, 15.6% (95% confidence interval 14.7-16.5) of children and adolescents aged 0-17 years were currently affected by at least one atopic disease. The 12-month prevalence rates of hay fever, atopic dermatitis, and asthma were 9.1% (8.4-9.8), 6.0% (5.4-6.6), and 4.1% (3.6-4.6), respectively. In all, 2.2% (1.9-2.6) of the children and adolescents were currently suffering from contact dermatitis. Compared with the baseline KiGGS survey from 2003 to 2006, a higher percentage of participants reported the occurrence of asthma within the past 12 months in the recent KiGGS Wave 1 (4.1 vs. 3.2%; p = 0.0034). The total increase is mainly due to higher prevalence rates among 0- to 6-year-olds, especially in girls. Higher 12-month prevalence rates can be also observed for hay fever among 0- to 6-year-olds, especially in girls, although the total increase is not statistically significant (9.1 vs. 8.3%; p = 0.08). There was a declining trend for atopic dermatitis: 6.8% (2003-2006) vs. 5.4% (2009-2012); p = 0.0015.

[The first KiGGS follow-up (KiGGS Wave 1): study conduct, sample design, and response]. / Die erste KiGGS-Folgebefragung (KiGGS Welle 1): Studiendurchführung, Stichprobendesign und Response.

The "German Health Interview and Examination Survey for Children and Adolescents" (KiGGS) is part of the health monitoring system of the Robert Koch Institute (RKI). Following the KiGGS baseline study (2003 - 06), which comprised interviews and physical examinations of 0- to 17-year-old participants, KiGGS Wave 1 (2009 - 2012) was carried out as a telephone-based survey. In addition to providing longitudinal data, a second essential aim of KiGGS is to regularly provide population-based cross-sectional data on the health situation of children and adolescents aged 0-17 years living in Germany. Therefore, the study population of KiGGS Wave 1 consists of re-invited participants from the baseline study (KiGGS cohort), supplemented by newly invited children aged 0-6 years. The newly invited participants were randomly chosen from local population registries in the 167 baseline sample points. This method was chosen to supplement the sample with younger age groups. This article focuses on the age groups from 0 to 17 years, which are relevant for prevalence estimations among children and adolescents. In total 12,368 children and adolescents took part; among them 4,455 newly invited and 7,913 re-invited participants (response 38.8 and 72.9%, respectively). A comparison of the net sample with the resident German population (0-17 years) regarding particular population characteristics and an analysis of the relationship between the re-participation rate and certain characteristics collected in the baseline study (7-17 years) suggest a mostly unbiased sample. To account for certain aspects of the population and nonresponse, cross-sectional and trend analyses were partially corrected by weighting factors.

Pregnancy risk factors for very premature delivery: what role do hypertension, obesity and diabetes play?

PURPOSE: Very premature delivery is a major cause of infant morbidity and mortality. Obesity, diabetes and pregnancy hypertension are known risk factors for pregnancy complications. The study aimed to scrutinize differences of pregnancy complications in a cohort of very premature deliveries compared to a national group. METHODS: In a multicenter study performed between January 2009 and December 2010 including 1,577 very low birth weight (VLBW) infants, we compared parental reported pregnancy problems of VLBW infants with a national cohort (KIGGS). We compared reported pregnancy complications to reasons for premature delivery and neonatal outcome within the group of VLBW infants. RESULTS: While parents of the national cohort reported pregnancy-induced hypertension in 8 %, parents of VLBW infants reported this complication more frequently (27 %). Mothers of the national cohort were significantly younger (1 year), suffered less from obesity, anaemia, diabetes. Regression analysis showed that hypertension (OR = 5.11) and advanced maternal age (OR = 1.03) increased the risk for premature birth. Women with hypertension were likely to experience a clinically indicated premature delivery, had more VLBW infants with a moderate growth restriction, but less multiples and their infants had less intraventricular haemorrhages grade 3 or 4. Otherwise, neonatal outcome was correlated with gestational age but not with the pregnancy complications diabetes, hypertension or obesity. CONCLUSION: Premature birth seems to be correlated to gestational hypertension and associated problems in about » of VLBW infants. Further studies should focus on preventing and treating gestational hypertension to avoid premature delivery and associated neonatal morbidity.

[Prevalence of sensitisation to aeraoallergens and food allergens: results of the German Health Interview and Examination Survey for Adults (DEGS1)]. / Prävalenz von Sensibilisierungen gegen Inhalations- und Nahrungsmittelallergene : Ergebnisse der Studie zur Gesundheit Erwachsener in Deutschland (DEGS1).

In view of the increasing prevalence of allergies, up-to-date data on the prevalence of allergic sensitisation are of major interest. In the German Health Interview and Examination Survey for Adults (DEGS1) (2008-2011) blood samples from a population-based sample of 7,025 participants aged 18 to 79 years were analysed for specific IgE antibodies against 50 common single allergens and screened for common aeroallergens (SX1) and grass pollen (GX1). In all, 48.6 % of the participants were sensitised to at least one allergen. Overall, men were more frequently sensitised to at least one allergen than women were. Sensitisations to at least one allergen were more common among younger than older participants and among participants with a higher socio-economic status. In all, 33.6 % of the participants were sensitised to common aeroallergens, 25.5 % to food allergens and 22.6 % to wasp or bee venoms. Compared with the German National Health Interview and Examination Survey 1998 (GNHIES98), the prevalence of sensitisation to common aeroallergens increased from 29.8 to 33.6 %.This increase was statistically significant only in women. The results of DEGS1 still showed a high prevalence of allergic sensitisation. An English full-text version of this article is available at SpringerLink as supplemental.

[Relationship between physical activity and health in children and adolescents. Results of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS) and the "Motorik-Modul" (MoMo)]. / Zum Zusammenhang zwischen körperlicher Aktivität und Gesundheit bei Kindern und Jugendlichen. Ergebnisse des Kinder- und Jugendgesundheitssurveys (KiGGS) und des Motorik-Moduls (MoMo).

The question of whether physical activity is associated with positive aspects of health becomes increasingly more important in the light of the health status in today's children and adolescents and due to the changing lifestyle with respect to everyday activity. The German Health Interview and Examination Survey for Children and Adolescents (KiGGS) collected the first set of nationwide representative cross-sectional data to examine the relationship between health and physical activity. Taking sociodemographic parameters into consideration, the results suggest a positive association between self-estimated general health and several types of physical activity. The results vary with respect to gender and type of physical activity. For methodological reasons, causal conclusions can only be drawn after longitudinal data of the second wave of KiGGS are available.

[The KiGGS study. Nationwide representative longitudinal and cross-sectional study on the health of children and adolescents within the framework of health monitoring at the Robert Koch Institute]. / Die KiGGS-Studie. Bundesweit repräsentative Längs- und Querschnittstudie zur Gesundheit von Kindern und Jugendlichen im Rahmen des Gesundheitsmonitorings am Robert Koch-Institut.

From 2003 to 2006 the KiGGS Baseline Study was conducted, including a clustered random sample of 167 sample points and 17,641 children and adolescents from 0 to 17 years, as well as their parents in 167 sample points. The children and adolescents were medically and physically examined, and their parents answered questions about physical, psychological and social aspects of their children's health, as did, from 11 years on, the children and adolescents themselves. Within the framework of the nationwide health monitoring at the Robert Koch Institute, the KiGGS study is being continued as a prospective cohort study with an interval of approximately 5 years between follow-ups. The study sample will be cross-sectionally refilled with younger age groups at each time of measurement. The assessment of the KiGGS core study follows a core indicator concept, which is modularly complemented by external scientific cooperation partners. The field work of the first wave (KiGGS Wave 1), a telephone survey, will continue until June 2012. The second follow-up (KiGGS Wave 2) will again combine examinations and interviews, starting in 2013. On the basis of the nationally representative KiGGS data, important questions about health policy can be answered, such as trends and trajectories of health. Important results are expected, among others concerning trends in overweight and obesity, the incidence of atopic diseases, and the persistency or remission of psychopathological symptoms and disorders.

[Prevalence of helmet use in children and adolescents in Germany and preventable bicycle-related head injuries]. / Helmtragequoten bei Kindern und Jugendlichen in Deutschland und vermeidbare Kopfverletzungen bei Fahrradunfällen.

INTRODUCTION: Head injuries are the main cause of death in bicycle-related accidents among children and adolescents. According to a Cochrane Review, the risk of head injury (OR 0.31; 95% CI 0.26-0.37) or brain injury (OR 0.31; 95% CI 0.23-0.42) decreases by 69% if a helmet is worn. This study presents the prevalence of helmet use in cycling children and adolescents in Germany and the proportion of head injuries that could be prevented by wearing helmets. The potential effects of increased helmet wearing rates on the population attributable risk percentage for head injuries (PAR%) are demonstrated. METHODS: The prevalence of helmet use in children aged 3-17 years was analysed using data from the German Health Interview and Examination Survey for Children and Adolescents (KiGGS). The percentage of head injuries preventable by helmet use in this group is estimated by calculating PAR%. Prevalence rates of helmet use and odds ratios from a Cochrane Review about the effectiveness of bicycle helmets for the prevention of head injuries were used for analysis. The potential effect of increased helmet use is shown in 3 scenarios by means of differences of PAR% values in the most relevant age groups. RESULTS: The older the children, the less likely they are to wear a helmet: 89.5% (95% CI 88.0%-90.8%) of the 3- to 6-year-old children wear a helmet when cycling but only 11.0% (95% CI 9.3%-12.9%) of 14- to 17-year-old adolescents do. In the youngest group (3-6 years) 19% of bicycle-related head injuries are attributable to the non-use of helmets, but this proportion rises to 67% in the oldest group (14-17 years). The PAR% of head injuries associated with not wearing a helmet may be reduced by more than a third by increasing the helmet wearing rate to 67% (2 out of 3) among adolescents, and may be reduced to half if 75% of adolescents wore a helmet. CONCLUSION: Particularly older children and adolescents hardly use bicycle helmets, hence the rate of preventable head injury is high. Efforts towards increasing helmet use should address all age groups with a particular focus on school-aged children and adolescents.

[Suspected adverse reactions after vaccination. Results from the German Health Interview and Examination Survey for Children and Adolescents. Part I: descriptive analyses]. / Impfnebenwirkungen bei Kindern und Jugendlichen. Ergebnisse des Kinder- und Jugendgesundheitssurveys. Teil 1: Deskriptive Analysen.

The decreasing incidence of vaccine-preventable infectious diseases and their complications redirects public attention to the safety risks of vaccinations. Collation of resilient vaccine adverse reaction data from passive and active surveillance systems as well as epidemiological studies is indispensable. From 2003-2006, the representative National Health Interview and Examination Survey for Children and Adolescents ("Kinder- und Jugendgesundheitssurvey," KiGGS) retrospectively collected information about vaccines, vaccination dates, and suspected vaccine-related adverse events. A total of 15,958 participants (<17 years of age) were included in the analyses. Parents of 332 (2.1%; 95% CI 1.8-2.5) children and adolescents reported that one or more vaccinations were poorly tolerated. The reported adverse reactions were largely in accordance with information given in the summaries of product characteristics of the respective vaccines. Calculated rates of adverse reactions were below the known rates. KiGGS allowed the retrospective collection of suspected adverse reactions from a large number of vaccinations, thereby providing data even on rare adverse events. No unusual pattern was observed. The information obtained on suspected adverse reactions does not change the positive benefit-risk ratio of vaccinations.

[Suspected adverse reactions after vaccination. Results from the German Health Interview and Examination Survey for Children and Adolescents. Part 2: predictors of parental reporting of suspected adverse reactions after vaccinations]. / Impfnebenwirkungen bei Kindern und Jugendlichen. Ergebnisse des Kinder- und Jugendgesundheitssurveys. Teil 2: Einflussfaktoren auf elterliche Berichte über Impfnebenwirkungen.

Each method to monitor vaccine safety has strengths and limitations. Therefore, vaccine safety monitoring should rely on different types of data sources. Methods commonly rely on patient-reported adverse reactions. Little is, however, known about factors that may affect the probability with which patients report adverse reactions to vaccines. From 2003-2006, the representative National Health Interview and Examination Survey for Children and Adolescents ("Kinder- und Jugendgesundheitssurvey", KiGGS) retrospectively collected information about vaccines, vaccination dates, and suspected vaccine related adverse reactions from a total of 17,641 participants (<17 years). Poorly tolerated vaccinations were more likely reported from parents living in former West Germany compared to former East Germany (OR 1.61; 95% CI 1.08-2.39), parents of children with special health care needs (OR 1.49; 95% CI 1.08-2.04), and from parents reporting reservations against vaccinations (OR 3.29; 95% CI 2.28-4.75). Parental reporting of adverse vaccine reactions appears to be associated with parental perception and assessment of possible adverse vaccine reactions, as well as with the parents' attitude towards immunization in general.

Population prevalence of obstructive sleep apnoea in a community of German third graders.

We aimed to estimate the population prevalence of obstructive sleep apnoea (OSA) in an urban community of German third graders (age range 7.3-12.4 yrs) and the diagnostic test accuracy of two OSA screening methods. Using a cross-sectional study design with a multi-stage sampling strategy, 27 out of 59 primary schools within the city limits of Hanover, Germany, were selected. 1,144 third graders were screened for symptoms and signs of OSA using questionnaires and nocturnal home pulse oximetry. 183 children underwent abbreviated nocturnal home polysomnography (OSA definition: apnoea/hypopnoea index ≥1) and 22 were diagnosed to suffer from OSA. In general, sensitivity for both screening methods was low (<0.6), while specificity was moderately high (mostly >0.7). Independent predictors for OSA were body mass index, history of allergy, a composite questionnaire score, and two oximetry-based criteria. Based on these variables and logistic regression, a prediction model (accuracy; 95% confidence interval: 0.86; 0.71-0.94) was constructed and applied to children who had not successfully undergone polysomnography. This resulted in nine additional OSA cases and an overall design-adjusted population prevalence (95% confidence interval) of 2.8% (1.5-4.1%). Clinical and oximetry findings may be helpful for screening and predicting OSA in primary school children.

Effects of latex avoidance on latex sensitization, atopy and allergic diseases in patients with spina bifida.

BACKGROUND: Ten years ago, avoidance measures such as the performance of latex-free operations were implemented in children with spina bifida. Since then, latex sensitization and latex allergy have decreased in this high-risk group. OBJECTIVE: To study the effect of primary latex-free prophylaxis on the prevalence of allergic diseases and atopy as a marker for sensitization spreading in children with spina bifida. METHODS: One hundred and twenty children with spina bifida born after the introduction of latex-free prophylaxis and operated on under latex-free conditions ('current group') were examined for latex sensitization, latex allergy, sensitization to aero- and food allergens and allergic diseases. Results were compared to a 'historic' (not latex-free operated) group of children with spina bifida and comparable age (n = 87) and to a recent sample of children from the general population (n = 12,403). RESULTS: In comparison with the 'historic group', latex sensitization (55% vs 5%, P < 0.001) and latex allergy (37% vs 0.8%, P < 0.001) were significantly reduced in the 'current group'. Furthermore, a significant reduction could be demonstrated for sensitization to aeroallergens (41.4% vs 20.8%, P = 0.001) and for allergic diseases (35% vs 15%, P = 0.001). The prevalence for atopy, sensitization to aero-/foodallergens and for allergic diseases in children of the 'current group' was similar to those in children of the weighted population sample. CONCLUSIONS: Latex avoidance in children with spina bifida prevents latex sensitization and latex allergy. Additionally, it also seems to prevent sensitization to other allergens and allergic diseases which might be explained by the prevention of sensitization spreading.

Low hepatitis B immunogenicity of a hexavalent vaccine widely used in Germany: results of the German Health Survey for Children and Adolescents, 2003-2006.

The success of childhood vaccination against hepatitis B relies on persistence of immunity into adolescence and adulthood. In 2000, two hexavalent vaccines with a hepatitis B component (Hexavac, Infanrix hexa) were introduced in Germany. Hexavac was withdrawn in 2005 amidst concerns about its long-term hepatitis B protection. We compared hepatitis B surface antibody (anti-HBs) levels in children fully vaccinated with Hexavac or Infanrix hexa (n=477) in a secondary data analysis of a large cross-sectional health survey in Germany. On average 2.4 years after vaccination, 25.3% of Hexavac vaccinees had anti-HBs levels <10 mIU/ml (95% CI 19.0-32.8) compared to 4.7% of Infanrix hexa vaccinees (95% CI 2.4-8.9). These findings suggest that short-term hepatitis B immunogenicity in Hexavac vaccinees may also be weaker. Further studies are warranted to assess whether Hexavac vaccinees should be re-vaccinated or receive a booster vaccination before these birth cohorts reach adolescence.

The impact of maternal education on intrauterine growth: a comparison of former West and East Germany.

BACKGROUND: Objective of this re-analysis of datasets from former East and West Germany was to examine the influence of maternal education on intrauterine growth in two different political and social systems. METHODS: Information on socio-demographic or lifestyle factors and pregnancy outcome was available for 3374 liveborn singletons from West Germany (1987/88) and 3070 from East Germany (1990/91). Multiple logistic regression was used to estimate the association between maternal education and the risk of delivering a small-for-gestational-age (SGA) newborn below the 10th percentile of birthweight. RESULTS: Women with the lowest education had a significantly elevated risk of SGA newborns compared to women with the highest education in West (odds ratio [OR] = 2.58, 95% CI : 1.17-5.67) and East Germany (OR = 2.77, 95% CI : 1.54- 5.00). The distribution of factors known to influence intrauterine growth varied with education in both states. After adjusting for these factors, women with the lowest educational level still had a higher risk of SGA birth: OR (West) = 2.02, 95% CI : 0.87-4.72; OR (East) = 1.95, 95% CI : 1.02-3.74. CONCLUSIONS: Our findings support the assumption that in former socialist countries health inequalities as a result of social inequalities existed.

Smoking during pregnancy and poor antenatal care: two major preventable risk factors for sudden infant death syndrome.

BACKGROUND: In this case-control study on sudden infant death syndrome (SIDS), the magnitude of the risk factors 'maternal smoking during pregnancy' and 'poor antenatal care' was assessed and the attributable proportions of SIDS incidence estimated. METHODS: Perinatal data from 190 SIDS cases, who died between 1986 and 1990 at age > 7 days and had a diagnosis of SIDS confirmed by autopsy, were compared to 5920 controls. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were computed by unconditional logistic regression. The attributable risk per cent among the exposed (AR%) and the population attributable risk per cent (PAR%) were calculated. RESULTS: Maternal smoking during pregnancy was associated with a more than twofold risk of SIDS (OR = 2.4; 95% CI: 1.7-3.4) and showed a significant dose-response. Low numbers of antenatal care visits were also associated with an increased risk of SIDS: OR = 1.6 (95% CI: 1.1-2.3) for 4.8 consultations and 2.9 (95% CI: 1.4-5.8) for 0-3 consultations; reference: > 8 consultations. Maternal smoking during pregnancy yielded an AR% of 58% (95% CI: 42-70) and a PAR% of 28% (95% CI: 16-40). The AR% for < or = 8 antenatal care visits versus > 8 consultations was 41% (95% CI: 16-59); the PAR% 10% (95% CI: 3-17). CONCLUSIONS: Assuming causality, our data suggest that a reduction of the prevalence of either risk factor by population-based interventions may yield a worthwhile public health impact in terms of a substantially lower SIDS incidence.

Approaches to the denominator in practice-based epidemiology: a critical overview.

OBJECTIVES: An accurate knowledge of the population at risk is a fundamental requirement for determining rates and making comparisons in epidemiological research. The major obstacle of studying the epidemiology of sentinel practice networks is the determination of population at risk, in this case, the reference population of medical practices. This article is intended to give a brief overview of major denominator approaches used in practice based epidemiology today, to discuss their underlying assumptions, their strengths and limitations. DESIGN: The literature used in this paper was searched from Medline databases of 1970-1997 using the logical expression "denominator and practice". More literature was identified from the references cited in those articles and from research reports that were available to the authors. MAIN RESULTS: There are various approaches to the denominator at different levels of complexity, which were presented akin to the well known "iceberg phenomenon": with only a small portion of the iceberg visible above the surface, inference as to the size of the invisible part may still be made under certain assumptions. Crude numbers of cases may still reflect trends in the true epidemiology of disease and may be useful for time-series analyses. Differences in the number of network participants over time and across region may be controlled for by using the number of sentinel practices as a denominator. The number of consultations is a first step towards a population-based denominator, reflecting characteristics of both patients and the network. The yearly or quarterly contact group is a true person-based denominator, yet disregarding the population not consulting. The population in practices' catchment areas can be either determined from patient lists or estimated using mathematical models. The ideal denominator is the total population in a geographically defined area, though this information can be directly related to medical practices only in very few countries. CONCLUSIONS: Although a person, or ideally a population-based denominator is desirable, even "lower-level" denominators may be suitable for certain research topics. In countries without patient registration, the estimation of incidences and prevalences has many methodological uncertainties that limit the use of sentinel practice systems. Assuming representativeness, valid analytical or time-series studies, however, can still be carried out even if there is very little information on the population at risk covered by particular medical practices.

Organochlorine residues in human breast milk: analysis through a sentinel practice network.

STUDY OBJECTIVE: The study aimed to assess through a sentinel practice network the validity of data on levels of organochlorine residues in human milk along with personal, lifestyle, and exposure variables of breastfeeding women; to compare the results of this new approach with those of the Lower Saxony breast milk surveillance programme; and to test hypotheses on potential determinants of contamination levels. DESIGN: Eligible women were enrolled into this cross sectional study by a network of 51 paediatric practices when bringing their babies for a U3 infant screening examination (4th to 6th week after delivery). Lifestyle and exposure factors were obtained by questionnaire. All milk samples were analysed for hexachlorocyclohexane, hexachlorbenzole, DDT, dieldrin, polychlorinated biphenyls (PCB) and heptachlor; half the samples were also analysed for dioxin. Analytic statistics were computed using polychotomous logistic regression (PLR). SETTING: The study was conducted in Lower Saxony, Germany, from summer 1992 to summer 1993. PARTICIPANTS: Altogether 156 primiparous, breast feeding German women, aged 25-35 years, who had been born and had grown up in West Germany, were studied. MAIN RESULTS: Compared with the regular programme, participants in this study had their milk analysed sooner after delivery and were more likely to have grown up in rural areas, less likely to have been exposed to hazardous substances, less likely to have a diet of health food, and slightly less likely to be a smoker at the time of the study. Breast milk contamination levels were comparable in both studies, and in all but two cases well below the tolerable concentrations established by the Deutsche Forschungsgemeinschaft (German Research Fellowship). After adjustment for potential confounders using polychotomous logistic regression, there were statistically significant positive associations between breast milk contamination and age (PCB, test for trend: p = 0.006), average dietary fat intake per week (dioxin, p = 0.01), and proximity of residence to hazardous sites (dioxin, p < 0.05), and negative associations between residue levels and relative body weight at the time of the study (PCB; p < 0.0001) and difference in body weight (weight minus weight before the pregnancy; PCB, p = 0.0002), respectively. CONCLUSIONS: Sentinel practice networks are a feasible and low-biased approach to population based breast milk studies. The contamination levels and associations found are biologically plausible and comparable with the results of other studies. To reduce organochlorine residue levels in human milk in the short term, breast-feeding women should be advised not to try to reduce their weight until after lactation. Public promotion of a lower dietary fat intake may reduce the lifetime accumulation of organochlorine compounds in the human body fat tissue in the long term, resulting in lower concentrations in breast milk as well.

Contamination of human breast milk with organochlorine residues: a comparison between East and West Germany through sentinel practice networks.

STUDY OBJECTIVE: The aim of the study was to assess and compare the contamination of human breast milk with organochlorine residues through two sentinel practice networks in Lower Saxony, a state of former West Germany, and Saxony-Anhalt, a state of former East Germany. DESIGN: Eligible women were enrolled in this cross sectional study by a network of 51 paediatric practices in Lower Saxony and 44 in Saxony-Anhalt when bringing their babies for a regular screening examination four to six weeks after delivery. Sociodemographic, lifestyle, and exposure factors were determined by questionnaire. Milk samples were analysed for hexachlorocyclohexane (HCH), hexachlorbenzole (HCB), DDT, dieldrin, polychlorinated biphenyls (PCB), and heptachlorepoxid (HCE); half the samples were also analysed for dioxin. Analytic statistics were computed using multiple logistic regression. SETTING: The study was conducted in Lower Saxony, Germany, from July 1992 to June 1993, and in Saxony-Anhalt, Germany, from January to June 1995. PARTICIPANTS: 156 primiparous, breast-feeding women from Lower Saxony and 113 from Saxony-Anhalt were studied, who either were born and raised in former West or East Germany, respectively. MAIN RESULT: Mean age of mothers and children differed significantly between the two study groups. In Lower Saxony all but two milk samples were well below the tolerable concentrations established by the German Research Council (Deutsche Forschungsgemeinschaft (DFG)). In Saxony-Anhalt no participant had concentrations above those recommended by the DFG. After adjustment for age of mother and child, occupational and non-occupational pesticide contact, DDT and beta-HCH concentrations were significantly lower in Lower Saxony; HCE and dieldrin concentrations were lower in Saxony-Anhalt. No differences between the two states were found for PCB, HCB, gamma-HCH, and dioxin. CONCLUSIONS: Breast milk contamination levels in former East German Saxony-Anhalt exceeded the contamination in Lower Saxony only for DDT and beta-HCH.