Prevalence of vaccine-derived hepatitis B surface antibodies in children and adolescents in Germany: results from a population-based survey, 2014-2017

INTRODUCTION

Childhood vaccination against hepatitis B has been recommended in Germany since 1995. WHO defines a primary vaccination series as successful if the initial hepatitis B surface antibody (anti-HBs) level is ≥ 10 IU/L directly after vaccination. Anti-HBs levels vary depending on the number of doses, type of vaccine, and time interval between the last two doses. In 2021, Germany began to recommend three instead of four doses of polyvalent hepatitis-B-containing vaccines. Our aim was to estimate the proportion of vaccinated children in Germany with anti-HBs levels < 10 IU/L, 10-99 IU/L, and ≥ 100 IU/L by number and type of vaccine, and assess if number of doses and compliance with recommended time interval between the last two doses are associated with an anti-HBs level ≥ 10 IU/L when considering type of vaccine and time since last dose.

METHODS

We used data from a national cross-sectional study (2014-2017) of children (3-17 years). We excluded participants with unknown vaccination dates, unreadable or incomplete vaccination cards, and hepatitis B virus (HBV)-positive participants. We defined a recommended schedule as a vaccination series with at least six months between the two last doses and having three doses or more. We calculated weighted anti-HBs sero-prevalence for three anti-HBs levels: < 10 IU/L, 10-99 IU/L and ≥ 100 IU/L. We fitted two logistic regression models to examine the relationship between number of doses and recommended schedule on anti-HBs levels (≥ 10 IU/L and ≥ 100 IU/L) considering time since last dose and type of vaccine (Infanrix, Hexavac, Monovalent).

RESULTS

We included 2,489 participants. The weighted proportion of vaccinated children per anti-HBs level was < 10 IU/L: 36.3% [95%CI 34.0-38.7%], 10-99 IU/L: 35.7% [33.2-38.2%] and ≥ 100 IU/L: 28.0% [25.9-30.2%]. We did not find an association between a recommended schedule of three versus four doses and anti-HBs ≥ 10 IU/L or ≥ 100 IU/L.

CONCLUSIONS

Anti-HBs levels in later childhood were about equal, whether children received three or four doses. This implies that the change in the recommendations does not affect the anti-HBs level among children in Germany. Future studies are needed on the association of anti-HBs levels and adequate sustained protection against HBV.

A bead-based multiplex assay covering all coronaviruses pathogenic for humans for sensitive and specific surveillance of SARS-CoV-2 humoral immunity

Serological assays measuring antibodies against SARS-CoV-2 are key to describe the epidemiology, pathobiology or induction of immunity after infection or vaccination. Of those, multiplex assays targeting multiple antigens are especially helpful as closely related coronaviruses or other antigens can be analysed simultaneously from small sample volumes, hereby shedding light on patterns in the immune response that would otherwise remain undetected. We established a bead-based 17-plex assay detecting antibodies targeting antigens from all coronaviruses pathogenic for humans: SARS-CoV-2, SARS-CoV, MERS-CoV, HCoV strains 229E, OC43, HKU1, and NL63. The assay was validated against five commercial serological immunoassays, a commercial surrogate virus neutralisation test, and a virus neutralisation assay, all targeting SARS-CoV-2. It was found to be highly versatile as shown by antibody detection from both serum and dried blot spots and as shown in three case studies. First, we followed seroconversion for all four endemic HCoV strains and SARS-CoV-2 in an outbreak study in day-care centres for children. Second, we were able to link a more severe clinical course to a stronger IgG response with this 17-plex-assay, which was IgG1 and IgG3 dominated. Finally, our assay was able to discriminate recent from previous SARS-CoV-2 infections by calculating the IgG/IgM ratio on the N antigen targeting antibodies. In conclusion, due to the comprehensive method comparison, thorough validation, and the proven versatility, our multiplex assay is a valuable tool for studies on coronavirus serology.

SARS-CoV-2 seroconversion in children attending daycare versus adults in Germany between October 2020 and June 2021

BACKGROUND

Data on seroconversion rates after SARS-CoV-2 infection in young children (<6 years) is scarce. The present study compares seroconversion rates between young children and adults and identifies associated factors.

METHODS

The COALA study ("Corona-outbreak-related examinations in daycare centers") investigated transmission dynamics of SARS-CoV-2 in daycare centers and associated households (10/2020-06/2021). 114 individuals tested positive for SARS-CoV-2 through PCR either prior to the study period by health authorities or in PCR testing during the study period. Two capillary blood samples were obtained within five weeks consecutively and tested for SARS-CoV-2 IgG-antibodies (second sampling depending on positive PCR). Results from 91 participants (38 young children 1-6 years, 53 adults) were included in the analyses.

RESULTS

Seroconversion rate in young children is significantly higher than in adults (97.4% versus 66%). High viral load and longer time interval between the probable date of infection and antibody testing are associated with seroconversion.

CONCLUSIONS

Our findings depict substantial development of specific antibodies in young children after SARS-CoV-2 infection. This may provide temporary protection from re-infection for young children or severe disease for this age group.

Long-term health consequences among individuals with SARS-CoV-2 infection compared to individuals without infection: results of the population-based cohort study CoMoLo Follow-up

BACKGROUND

Most of the previous studies on health sequelae of COVID-19 are uncontrolled cohorts and include a relatively short follow-up. This population-based multi-center cohort study examined health consequences among individuals about 1 to 1.5 years after SARS-CoV-2 infection compared with non-infected.

METHODS

The study population consisted of adults (≥ 18 years) from four municipalities particularly affected by the COVID-19 pandemic in the year 2020 who completed a detailed follow-up questionnaire on health-related topics. Exposure was the SARS-CoV-2 infection status (based on IgG antibodies, PCR test, or physician-diagnosis of COVID-19) at baseline (May to December 2020). Outcomes assessed at follow-up (October 2021 to January 2022; mean: 452 days) included recurrent or persistent health complaints, incident diseases, health-related quality of life (PROMIS-29), subjective health, and subjective memory impairment. Logistic and linear regression models were adjusted for baseline sociodemographic and lifestyle characteristics (age, sex, municipality, education, smoking, body mass index), pre-existing health conditions (chronic disease/health problem, health-related activity limitation, depressive/anxiety disorder), and follow-up time.

RESULTS

Among 4817 participants, 350 had a SARS-CoV-2 infection at baseline and 4467 had no infection at baseline or during follow-up. Those with an infection statistically significantly more often reported 7 out of 18 recurrent or persistent health complaints at follow-up: smell/taste disorders (12.8% vs. 3.4%, OR 4.11), shortness of breath (23.0% vs. 9.5%, 3.46), pain when breathing (4.7% vs. 1.9%, 2.36), fatigue (36.9% vs. 26.1%, 1.76), weakness in legs (12.8% vs. 7.8%, 1.93), myalgia/joint pain (21.9% vs. 15.1%, 1.53) and cough (30.8% vs. 24.8%, 1.34) and 3 out of 6 groups of incident diseases: liver/kidney (2.7% vs. 0.9%, 3.70), lung (3.2% vs. 1.1%, 3.50) and cardiovascular/metabolic (6.5% vs. 4.0%, 1.68) diseases. Those with an infection were significantly more likely to report poor subjective health (19.3% vs. 13.0%, 1.91), memory impairment (25.7% vs. 14.3%, 2.27), and worse mean scores on fatigue and physical function domains of PROMIS-29 than non-infected.

CONCLUSION

Even after more than one year, individuals with SARS-CoV-2 infection showed an increased risk of various health complaints, functional limitations, and worse subjective well-being, pointing toward profound health consequences of SARS-CoV-2 infection relevant for public health.

Seroprevalence, seroconversion and seroreversion of Borrelia burgdorferi-specific IgG antibodies in two population-based studies in children and adolescents, Germany, 2003 to 2006 and 2014 to 2017

BackgroundLyme borreliosis (LB), caused by Borrelia burgdorferi (Bb), is the most common tick-borne infection in Germany. Antibodies against Bb are prevalent in the general population but information on temporal changes of prevalence and estimates of seroconversion (seroincidence) and seroreversion are lacking, especially for children and adolescents.AimWe aimed at assessing antibodies against Bb and factors associated with seropositivity in children and adolescents in Germany.MethodsWe estimated seroprevalence via two consecutive cross-sectional surveys (2003-2006 and 2014-2017). Based on a longitudinal survey component, we estimated annual seroconversion/seroreversion rates.ResultsSeroprevalence was 4.4% (95% confidence interval (CI): 3.9-4.9%) from 2003 to 2006 and 4.1% (95% CI: 3.2-5.1%) from 2014 to 2017. Seroprevalence increased with age, was higher in male children, the south-eastern regions of Germany and among those with a high socioeconomic status. The annual seroconversion rate was 0.3% and the annual seroreversion rate 3.9%. Males were more likely to seroconvert compared with females. Low antibody levels were the main predictor of seroreversion.ConclusionWe did not detect a change in seroprevalence in children and adolescents in Germany over a period of 11 years. Potential long-term changes, for example due to climatic changes, need to be assessed in consecutive serosurveys. Seroconversion was more likely among children and adolescents than among adults, representing a target group for preventive measures. Seroreversion rates are over twice as high in children and adolescents compared with previous studies among adults. Thus, seroprevalence estimates and seroconversion rates in children are likely underestimated.

Monitoring the SARS-CoV-2 Pandemic: Prevalence of Antibodies in a Large, Repetitive Cross-Sectional Study of Blood Donors in Germany—Results from the SeBluCo Study 2020–2022

SARS-CoV-2 serosurveillance is important to adapt infection control measures and estimate the degree of underreporting. Blood donor samples can be used as a proxy for the healthy adult population. In a repeated cross-sectional study from April 2020 to April 2021, September 2021, and April/May 2022, 13 blood establishments collected 134,510 anonymised specimens from blood donors in 28 study regions across Germany. These were tested for antibodies against the SARS-CoV-2 spike protein and nucleocapsid, including neutralising capacity. Seroprevalence was adjusted for test performance and sampling and weighted for demographic differences between the sample and the general population. Seroprevalence estimates were compared to notified COVID-19 cases. The overall adjusted SARS-CoV-2 seroprevalence remained below 2% until December 2020 and increased to 18.1% in April 2021, 89.4% in September 2021, and to 100% in April/May 2022. Neutralising capacity was found in 74% of all positive specimens until April 2021 and in 98% in April/May 2022. Our serosurveillance allowed for repeated estimations of underreporting from the early stage of the pandemic onwards. Underreporting ranged between factors 5.1 and 1.1 in the first two waves of the pandemic and remained well below 2 afterwards, indicating an adequate test strategy and notification system in Germany.

Nationally representative results on SARS-CoV-2 seroprevalence and testing in Germany at the end of 2020

Pre-vaccine SARS-CoV-2 seroprevalence data from Germany are scarce outside hotspots, and socioeconomic disparities remained largely unexplored. The nationwide representative RKI-SOEP study (15,122 participants, 18-99 years, 54% women) investigated seroprevalence and testing in a supplementary wave of the Socio-Economic-Panel conducted predominantly in October-November 2020. Self-collected oral-nasal swabs were PCR-positive in 0.4% and Euroimmun anti-SARS-CoV-2-S1-IgG ELISA from dry-capillary-blood antibody-positive in 1.3% (95% CI 0.9-1.7%, population-weighted, corrected for sensitivity = 0.811, specificity = 0.997). Seroprevalence was 1.7% (95% CI 1.2-2.3%) when additionally correcting for antibody decay. Overall infection prevalence including self-reports was 2.1%. We estimate 45% (95% CI 21-60%) undetected cases and lower detection in socioeconomically deprived districts. Prior SARS-CoV-2 testing was reported by 18% from the lower educational group vs. 25% and 26% from the medium and high educational group (p < 0.001, global test over three categories). Symptom-triggered test frequency was similar across educational groups. Routine testing was more common in low-educated adults, whereas travel-related testing and testing after contact with infected persons was more common in highly educated groups. This countrywide very low pre-vaccine seroprevalence in Germany at the end of 2020 can serve to evaluate the containment strategy. Our findings on social disparities indicate improvement potential in pandemic planning for people in socially disadvantaged circumstances.

Waning of SARS-CoV-2 IgG antibodies after vaccination: first results from the CoMoLo follow-up 2021

Background

In 2020, the study “Corona-Monitoring Lokal” (CoMoLo) assessed seroprevalences of SARS-CoV-2 IgG antibodies in four study locations that were particularly affected by outbreaks in the early stages of the pandemic in Germany. One of the objectives of the 2021 follow-up was to examine the development of immunological parameters over time, including the extent of IgG antibody waning after vaccination.

Methods

Venous blood specimens were collected from a sample of initial study participants over a 2-week period between May and October 2021, with an oversampling of seropositive or previously infected individuals. Levels of IgG antibodies to the SARS-CoV-2 spike protein were measured from serum using Anti-SARS-CoV-2-QuantiVac-ELISA (IgG) tests by Euroimmun. Information on SARS-CoV-2 vaccinations or known infections was collected via online questionnaires or telephone interviews.

Results

A total of 3328 participants (74% response) gave blood specimens for this follow-up study, with questionnaire information available for 2843 (85%) of these. Preliminary analyses suggest that in participants who had received two doses of a vaccine more than 3 weeks before giving blood (n = 1583), IgG levels decreased exponentially by about 9.8% (95%CI 9.1% - 10.4%) with each additional week since the last dose, when controlling for age, sex, and type of vaccine. There was evidence of this waning effect differing by vaccine type. Antibody levels also appear to decline with increasing age, according to preliminary results. Final results of the linear model used to assess the dynamics and predictive factors of antibody levels will be reported.

Conclusions

This follow-up study will add evidence to an improved understanding of antibody waning after SARS-CoV-2 vaccination. Preliminary results are in line with international studies and may be helpful for discussions on potential benefits of further vaccinations in Germany.

Key messages

• Antibodies induced by COVID-19 vaccination wane over time. The magnitude of this effect differs by vaccine type. Antibodies also decreased with increasing age.

• Our results may be helpful for discussions on potential benefits of further COVID-19 vaccinations in Germany.

SARS-CoV-2 Seroprevalence in Germany: results from the second wave of the RKI-SOEP study

Introduction

The first wave of the “Corona Monitoring bundesweit” (RKI-SOEP) study showed that shortly before the start of the German vaccination program only about 2% of adults (&gt; 18 years) had already experienced SARS-CoV-2 infection and more than half of these cases had been detected and notified. The objectives of the second wave of this study are to further investigate the spread of SARS-CoV-2 in Germanýs population aged over 14 years. It aims to determine the seroprevalence of infection- and vaccine-induced IgG antibodies against SARS-CoV-2. Finally, it examines health, demographic and socioeconomic risk and protective factors for infection and vaccine acceptance.

Methods

From November 2021 to February 2022, the second wave of this cross-sectional study collected biospecimens (capillary blood samples) and interview data, including information on infection and vaccination, from a nationwide population sample drawn from the German Socio-Economic Panel (SOEP). The dried self-collected blood samples were then analyzed for the detection of SARS-CoV-2 IgG antibodies by Euroimmun ELISA assay.

Results

Based on preliminary, unweighted data of around 11,000 participants aged &gt;14 years (52% response rate), we expect the final seroprevalence of SARS-CoV-2 antibodies to be in the range of 80 to 90%. Thus, around 10 to 20% of the German population may still be susceptible to a severe disease progression because they are neither infected nor vaccinated. Final results, weighted for non-response and adjusted for test sensitivity and specificity, will be presented.

Conclusions

The RKI-SOEP-2 study will be pivotal in both, contributing to an improved understanding of SARS-CoV-2 propagation in different regional and sub-group settings and in identifying vulnerable target groups that need to be protected against future infections.

Key messages

• Dried blood self-sampling in a nationwide sample is a robust tool to estimate seroprevalence at a population level.

• As of February 2022, presumably 80 to 90% of the German population has previously been infected and/or vaccinated against SARS-CoV-2.

Prevalence of Chlamydia trachomatis in the general population in Germany – a triangulation of data from two population-based health surveys and a laboratory sentinel system

Background

Chlamydia trachomatis (chlamydia) is a common, frequently asymptomatic, sexually transmitted infection. It can result in severe sequelae, such as ectopic pregnancy and infertility. In Germany, chlamydia is not notifiable. An opportunistic screening program for women < 25 years was introduced in 2008. The aim of this research was to triangulate different data sources to describe the epidemiological situation of chlamydia in Germany and to investigate whether the current target group of the chlamydia screening program aligns with these findings.

Methods

Urine specimens from participants from population-based health examination surveys of children (2014–17) and adults (2008–11) were tested for chlamydia, using nucleic acid amplification testing. These data were used to generate weighted chlamydia prevalence estimates by age group and sex. Data from a nationwide chlamydia laboratory sentinel system (2014–16) were used to calculate the positive proportion among individuals tested for chlamydia by age, sex and test reason.

Results

Using data from the population-based surveys, we found a chlamydia prevalence estimate of 2.8% (95% confidence interval (CI) 1.0–7.5%) among all 15- to 17-year-old girls and of 9.6% (95% CI 0.0–23) among those reporting to be sexually active. In adult women, we found the highest prevalence among 18- to 24-year-olds (all: 2.3%; 95% CI 1.0–5.3%; sexually active: 3.1%; 95% CI 1.3–7.0%). In adult men, we found the highest prevalence among 25- to 29-year-olds (all: 3.5%; 95% CI 1.6–7.7%; sexually active: 3.3%; 95% CI 1.3–7.8%). Data from the chlamydia laboratory sentinel showed the highest positive proportion among those opportunistically screened in 19-year-old women (6.1%; 95%- CI 5.9–6.4%), among those screened due to pregnancy in 15-year-old girls (10%; 95% CI 8.5–12%), and among those tested due to symptoms or a positive partner in 19-year-old women (10%; 95% CI 9.8–11%) and 19-year-old men (24%; 95% CI 22–26%).

Conclusions

Chlamydia seems to mainly affect adolescents and young adults in Germany, with similar overall prevalence in men and women, but with slightly different age distributions. Women at highest risk of chlamydia are covered by the current screening program but given the on-going discussions in high-income countries on cost-effectiveness and benefit-to-harm ratio of these programs, the program-aim needs reconsideration.

Infant Sleep Hazards and the Risk of Sudden Unexpected Death in Infancy

OBJECTIVE

To examine the effects of infant sofa-sleeping, recent use by caregivers of alcohol, cannabis, and/or other drugs, and bed type and pillows, on the risk of sudden unexpected death in infancy (SUDI) in New Zealand.

STUDY DESIGN

A nationwide prospective case-control study was implemented between March 2012 and February 2015. Data were collected during interviews with parents/caregivers. "Hazards" were defined as infant exposure to 1 or more of sofa-sleeping and recent use by caregivers of alcohol, cannabis, and other drugs. The interaction of hazards with tobacco smoking in pregnancy and bed sharing, including for very young infants, and the difference in risk for Māori and non-Māori infants, also were assessed.

RESULTS

The study enrolled 132 cases and 258 controls. SUDI risk increased with infant sofa-sleeping (imputed aOR [IaOR] 24.22, 95% CI 1.65-356.40) and with hazards (IaOR 3.35, 95% CI 1.40-8.01). The SUDI risk from the combination of tobacco smoking in pregnancy and bed sharing (IaOR 29.0, 95% CI 10.10-83.33) increased with the addition of 1 or more hazards (IaOR 148.24, 95% CI 15.72-1398), and infants younger than 3 months appeared to be at greater risk (IaOR 450.61, 95% CI 26.84-7593.14).

CONCLUSIONS

Tobacco smoking in pregnancy and bed sharing remain the greatest SUDI risks for infants and risk increases further in the presence of sofa-sleeping or recent caregiver use of alcohol and/or cannabis and other drugs. Continued implementation of effective, appropriate programs for smoking cessation, safe sleep, and supplying safe sleep beds is required to reduce New Zealand SUDI rates and SUDI disparity among Māori.

SARS-CoV-2 Transmissibility Within Day Care Centers-Study Protocol of a Prospective Analysis of Outbreaks in Germany

Introduction: Until today, the role of children in the transmission dynamics of SARS-CoV-2 and the development of the COVID-19 pandemic seems to be dynamic and is not finally resolved. The primary aim of this study is to investigate the transmission dynamics of SARS-CoV-2 in child day care centers and connected households as well as transmission-related indicators and clinical symptoms among children and adults. Methods and Analysis: COALA ("Corona outbreak-related examinations in day care centers") is a day care center- and household-based study with a case-ascertained study design. Based on day care centers with at least one reported case of SARS-CoV-2, we include one- to six-year-old children and staff of the affected group in the day care center as well as their respective households. We visit each child's and adult's household. During the home visit we take from each household member a combined mouth and nose swab as well as a saliva sample for analysis of SARS-CoV-2-RNA by real-time reverse transcription polymerase chain reaction (real-time RT-PCR) and a capillary blood sample for a retrospective assessment of an earlier SARS-CoV-2 infection. Furthermore, information on health status, socio-demographics and COVID-19 protective measures are collected via a short telephone interview in the subsequent days. In the following 12 days, household members (or parents for their children) self-collect the same respiratory samples as described above every 3 days and a stool sample for children once. COVID-19 symptoms are documented daily in a symptom diary. Approximately 35 days after testing the index case, every participant who tested positive for SARS-CoV-2 during the study is re-visited at home for another capillary blood sample and a standardized interview. The analysis includes secondary attack rates, by age of primary case, both in the day care center and in households, as well as viral shedding dynamics, including the beginning of shedding relative to symptom onset and viral clearance. Discussion: The results contribute to a better understanding of the epidemiological and virological transmission-related indicators of SARS-CoV-2 among young children, as compared to adults and the interplay between day care and households.

Seroepidemiological study on the spread of SARS-CoV-2 in Germany: Study protocol of the CORONA-MONITORING bundesweit' study (RKI-SOEP study)

The SARS-CoV-2 coronavirus has spread rapidly across Germany. Infections are likely to be under-recorded in the notification data from local health authorities on laboratory-confirmed cases since SARS-CoV-2 infections can proceed with few symptoms and then often remain undetected. Seroepidemiological studies allow the estimation of the proportion in the population that has been infected with SARS-CoV-2 (seroprevalence) as well as the extent of undetected infections. The ‘CORONA-MONITORING bundesweit’ study (RKI-SOEP study) collects biospecimens and interview data in a nationwide population sample drawn from the German Socio-Economic Panel (SOEP).

Participants are sent materials to self-collect a dry blood sample of capillary blood from their finger and a swab sample from their mouth and nose, as well as a questionnaire. The samples returned are tested for SARS-CoV-2 IgG antibodies and SARS-CoV-2 RNA to identify past or present infections.

The methods applied enable the identification of SARS-CoV-2 infections, including those that previously went undetected. In addition, by linking the data collected with available SOEP data, the study has the potential to investigate social and health-related differences in infection status. Thus, the study contributes to an improved understanding of the extent of the epidemic in Germany, as well as identification of target groups for infection protection.

Serology- and PCR-based cumulative incidence of SARS-CoV-2 infection in adults in a successfully contained early hotspot (CoMoLo study), Germany, May to June 2020

Three months after a coronavirus disease (COVID-19) outbreak in Kupferzell, Germany, a population-based study (n = 2,203) found no RT-PCR-positives. IgG-ELISA seropositivity with positive virus neutralisation tests was 7.7% (95% confidence interval (CI): 6.5-9.1) and 4.3% with negative neutralisation tests. We estimate 12.0% (95% CI: 10.4-14.0%) infected adults (24.5% asymptomatic), six times more than notified. Full hotspot containment confirms the effectiveness of prompt protection measures. However, 88% naïve adults are still at high COVID-19 risk.

Seroepidemiological study on the spread of SARS-CoV-2 in populations in especially affected areas in Germany - Study protocol of the CORONA-MONITORING lokal study

At a regional and local level, the COVID-19 pandemic has not spread out uniformly and some German municipalities have been particularly affected. The seroepidemiological data from these areas helps estimate the proportion of the population that has been infected with SARS-CoV-2 (seroprevalence), as well as the number of undetected infections and asymptomatic cases. In four municipalities which were especially affected, 2,000 participants will be tested for an active SARS-CoV-2 infection (oropharyngeal swab) or a past infection (blood specimen IgG antibody test). Participants will also be asked to fill out a short written questionnaire at study centres and complete a follow-up questionnaire either online or by telephone, including information on issues such as possible exposure, susceptability, symptoms and medical history. The CORONA-MONITORING lokal study will allow to determine the proportion of the population with SARS-CoV-2 antibodies in four particularly affected locations. This study will increase the accuracy of estimates regarding the scope of the epidemic, help determine risk and protective factors for an infection and therefore also identify especially exposed groups and, as such, it will be crucial towards planning of prevention measures.

Health-related quality of life and mental health in children and adolescents with strabismus - results of the representative population-based survey KiGGS

Background

To estimate the effect of strabismus (squinting) on mental health and health-related quality of life aspects in children and adolescents.

Methods

Data from the German Health Interview and Examination Survey for Children and Adolescents KiGGS (2003–2006 baseline survey; N = 14,835, aged 3 to 17 years, 49% girls) were examined. The presence of strabismus was derived by parental questionnaire, and health-related quality of life and mental health were investigated with the KINDL-R and Strengths and Difficulties Questionnaire. Associations between strabismus and outcomes were analyzed using multivariable linear and logistic regression models.

Results

Of 12,989 children without missing data, 579 children (4.5% of the sample) were reported to have strabismus. Children with strabismus had lower scores in the parent-reported KINDL-R total scale (adjusted beta = − 1.02; 95%CI: -1.86 to − 0.18; p = 0.018) and sub-scale ‘friends’ (adjusted beta = − 2.18; 95%CI: -3.56 to -0.80; p = 0.002) compared to children without strabismus. The presence of strabismus was also associated with more mental health problems like ‘hyperactivity/inattention’ (adjusted OR = 1.50; 95%CI: 1.14 to 1.98; p = 0.005), and ‘peer problems’ (adjusted OR = 1.35; 95%-CI: 1.05 to 1.74; p = 0.018) as reported by parents.

Conclusions

Strabismus in children and adolescents is associated with lower health-related quality of life.

Electronic supplementary material

The online version of this article (10.1186/s12955-019-1144-7) contains supplementary material, which is available to authorized users.

Serum vitamin D levels in Berliners of Turkish descent -a cross-sectional study

BACKGROUND

Vitamin D levels may differ between migrant and non-migrant populations, especially among non-western immigrants living in a country with limited sun exposure such as Germany. This study examined serum vitamin D concentration and associated factors among Berliners with and without Turkish background.

METHODS

Two samples (with and without Turkish roots) were recruited in the inner city of Berlin for a cross-sectional study assessing serum vitamin D concentration. Linear regression analyses were used to examine sociodemographic, lifestyle and medical factors associated with serum vitamin D levels.

RESULTS

In the analyses, we included 537 subjects (39% men and 61% women, age 43.2 ± 12.5 (mean ± standard deviation) years) with and 112 without Turkish background (46% men and 54% women, age 46.7 ± 14.6 years). The Turkish sample had lower mean (95%-Confidence Interval) vitamin D levels than the non-Turkish sample: 22.7 nmol/L (21.5;23.9) vs 34.7 nmol/L (31.9;37.5), p < 0.001. In the Turkish female subgroup, veiled women had considerably lower levels than unveiled women: 14.4 nmol/L (11.5;17.3) vs 24.9 nmol/L (23.1;26.7), p < 0.001. Multivariable regression analysis revealed that among the Berliners of Turkish descent, being active less than 150 min per day, and being overweight/obese were independently associated with a lower vitamin D concentration. In the non-migrant sample besides being overweight and obese, female sex was associated with lower vitamin D concentrations.

CONCLUSIONS

Serum vitamin D levels were considerably low in Berliners of Turkish descent, and especially in veiled women. Potentially modifiable factors of low vitamin D levels were high BMI and low physical activity. These findings should be considered in the development of future public health strategies for subpopulations with Turkish migration background.

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

AIM

To examine the sudden unexpected death in infancy (SUDI) disparity between Māori and non-Māori 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 Māori. Infant ethnicity was based on mother's ethnicity. Māori ethnicity was prioritised. Non-Māori includes Pacific, Asian, NZ European and Other.

RESULTS

There were 137 cases and 649 controls. The Māori SUDI rate was 1.41/1000 live births compared to 0.53/1000 for non-Māori. Parents/caregivers of 132 cases (96%) and 258 controls (40%) were interviewed. Smoking in pregnancy was associated with an equally increased SUDI risk for Māori (adjusted OR = 8.11, 95% CI = 2.64, 24.93) and non-Māori (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 Māori controls smoked during pregnancy (46.7%) than non-Māori (22.8%). The main contributor relating to increased SUDI risk for Māori/non-Māori 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. Māori infants are exposed more frequently to both behaviours because of the higher Māori smoking rate.

[Factors Associated with Behavioral Problems in Pre-School Age: Secondary Data Analysis of Routine Examination at School Enrolment 2010/2014 in the Hannover Region]

BACKGROUND AND AIM

Mental health and the prevalence of behavioral problems in children and adolescents has been gaining increasing concern in the last years. Several studies have addressed this issue in Germany. The aim of the study presented here is to examine factors associated with behavioral problems in pre-school children with focus on untreated morbidity.

METHODS

Data from the routine examination at school enrolment from 2010/11 to 2014/15 (n=40,675) in the Hannover region were analyzed. Behavioral problems and socio-emotional competences were assessed by the Strengths and Difficulties Questionnaire (SDQ) for parents and by doctors' observations during examination. Children who had already been treated for behavioral problems at the time of school enrolment were excluded from the study. Using multivariable logistic regression analyses, associations between behavioral problems and sociodemographic factors, duration of kindergarten attendance, family status and gestational age were assessed.

RESULTS

Education level of the parents, calculated from both parents' highest school and professional education level, is the strongest predictor for assessing behavioral problems of children at the time of school enrolment examination (OR 2.5; 95%-CI 2.3-2.7). Further factors are male sex (OR 1.5; 95%-CI 1.4-1.6), no kindergarten attendance (OR 1.3; 95%-CI 1.02-1.6) or kindergarten attendance of only one year (OR 1.4; 95%-CI 1.2-1.6), children living without their biological parents (OR 1.7; 95%-CI 1.2-2.4), preterm births (OR 1.5; 95%-CI 1.2-1.8) and age of 5 ½ years and younger (OR 1.4; 95%-CI 1.3-1.6) at the time of examination.

CONCLUSION

The results point to the importance of early development support for children from socially disadvantaged families. The results highlight public health-relevant points and enable the region Hannover to improve preventive efforts targeting such pre-school children.

Massa adiposa ligamenti falciformis or anterior abdominal fat pad - Its dimension and relation to body weight

The anterior abdominal fat pad is associated with the falciform ligament in the upper middle/right abdomen and is frequently seen there in diagnostic imaging. It varies greatly in size and has often been described as an incidental finding in adults and has hitherto rarely been regarded as being illness-relevant. The aim of this study has been to assess whether the dimension of the corpus adiposum may be associated with body mass index. Ultrasound findings of 26 patients from birth until adolescence were analyzed for this purpose. In addition, an example from a recent dissection course has been included. The structure is constantly found with its smallest dimension in newborns, with a slight increase in infancy. The average dimensions were 7.6 by 3.5 by 0.7cm. The cubic volume correlated with age, weight and body mass index, whereas the latter association was strongest. Our data suggest that routinely determined dimension of falciform fat may be a surrogate parameter of relative body weight in childhood.

New data for action. Data collection for KiGGS Wave 2 has been completed

The fieldwork of the second follow-up to the German Health Interview and Examination Survey for Children and Adolescents (KiGGS) was completed in August 2017. KiGGS is part of the Robert Koch Institute's Federal Health Monitoring. The study consists of the KiGGS cross-sectional component (a nationally representative, periodic cross-sectional survey of children and adolescents aged between 0 and 17) and the KiGGS cohort (the follow-up into adulthood of participants who took part in the KiGGS baseline study). KiGGS collects data on health status, health-related behaviour, psychosocial risk and protective factors, health care and the living conditions of children and adolescents in Germany. The first interview and examination survey (the KiGGS baseline study; undertaken between 2003 and 2006; n=17,641; age range: 0-17) was carried out in a total of 167 sample points in Germany. Physical examinations, laboratory analyses of blood and urine samples and various physical tests were conducted with the participants and, in addition, all parents and participants aged 11 or above were interviewed. The first follow-up was conducted via telephone-based interviews (KiGGS Wave 1 2009-2012; n=11,992; age range: 6-24) and an additional sample was included (n=4,455; age range: 0-6). KiGGS Wave 2 (2014-2017) was conducted as an interview and examination survey and consisted of a new, nationwide, representative cross-sectional sample of 0- to 17-year-old children and adolescents in Germany, and the second KiGGS cohort follow-up. The completion of the cross-sectional component of KiGGS Wave 2 means that the health of children and adolescents in Germany can now be assessed using representative data gained from three study waves. Trends can therefore be analysed over a period stretching to over ten years now. As the data collected from participants of the KiGGS cohort can be individually linked across the various surveys, in-depth analyses can be conducted for a period ranging from childhood to young adulthood and developmental processes associated with physical and mental health and the associated risk and protective factors can be explored. As such, KiGGS Wave 2 expands the resources available to health reporting, as well as policy planning and research, with regard to assessing the health of children and adolescents in Germany.

Vaccinations in the first year of life and risk of atopic disease - Results from the KiGGS study

BACKGROUND

The study focused on the question of whether and - if so - to what direction and extent immunisations in the 1st year may be associated with the risk of being diagnosed with atopic diseases after the 1st year of life.

METHODS

Data from the German Health Interview and Examination Survey for Children and Adolescents (KiGGS, 2003-2006) were analysed. For analyses of potential associations between vaccination status and risk of hay fever, atopic dermatitis or asthma, sample sizes of 15254, 14297, and 15262, respectively, were available.

RESULTS

Children with a sufficient TDPHiHeP vaccination at the end of the 1st year of life had a lower risk of being diagnosed with hay fever after the 1st year of life (adjusted prevalence ratio 0.85, 95% confidence interval 0.76-0.96). Analyses for associations between TDPHiHeP vaccination and risk of atopic dermatitis or asthma, or between age at onset of vaccination or of the number of antigens vaccinated in the 1st year of life and risk of atopic disease failed to yield statistical significance.

CONCLUSIONS

Our results provide no evidence that immunisations in the 1st year of life may increase the risk of atopic disease. If any association exists at all, our results may be interpreted as weakly supportive of the hypothesis that immunisations may slightly decrease the risk of atopy in later life.

Growth attainment in German children born preterm, and cardiovascular risk factors in adolescence. Analysis of the population representative KiGGS data

AIM

To compare the growth attainment of preterm children and their cardiovascular risk factors at adolescence with the values measured in term children in Germany.

METHODS

About 17,641 children aged 0 to <18 years were studied between 2003 and 2006 in the population representative German KiGGS survey ("German Health Interview and Examination Survey for Children and Adolescents") using questionnaires, physical examinations, standardized anthropometric and blood pressure measurements, and blood sample analyses. Analysis of covariance (ANCOVA) was employed for the analyses of anthropometric parameters.

RESULTS

About 11.8% of the 16,737 children with complete and valid data had been born preterm. After adjustment for covariates the estimated z-scores over the total age range were larger in term compared to preterm children for length/height (P<0.001; estimated difference B=0.277, 95% CI 0.191-0.362), head circumference (P<0.001; B=0.238, 95% CI 0.144-0.333), BMI (P=0.001; B=0.160, 95% CI 0.069-0.252), and skinfold thickness (P=0.220; B=0.058, 95% CI -0.035 to 0.151). The onset of pubertal development was slightly (but not significantly) earlier in term compared to preterm children. At 14 to <18 years, anthropometric and biochemical indicators of cardiovascular diseases were not worse in preterm compared to term children.

CONCLUSIONS

Preterm-born German adolescents remained significantly shorter, lighter, and had a smaller head circumference than term-born adolescents, but the risk indicators for cardiovascular diseases were not higher.

The combination of bed sharing and maternal smoking leads to a greatly increased risk of sudden unexpected death in infancy: the New Zealand SUDI Nationwide Case Control Study

BACKGROUND

Despite a major reduction in overall infant mortality, sudden unexpected death in infancy (SUDI) continues to be of concern in New Zealand, as the rate is high by international standards, and is even higher in indigenous Māori.

AIM

To identify modifiable risk factors for SUDI.

METHODS

A three-year (1 March 2012-28 February 2015) nationwide case-control study was conducted in New Zealand.

RESULTS

There were 137 SUDI cases, giving a SUDI mortality rate of 0.76/1,000 live births. The rate for Māori was 1.41/1,000, Pacific 1.01/1,000 and non-Māori non-Pacific (predominantly European) 0.50/1,000. The parent(s) of 97% of the SUDI cases were interviewed. Six hundred and forty-nine controls were selected and 258 (40%) were interviewed. The two major risk factors for SUDI were: maternal smoking in pregnancy (adjusted OR=6.01, 95% CI=2.97, 12.15) and bed sharing (aOR=4.96, 95% CI=2.55, 9.64). There was a significant interaction (p=0.002) between bed sharing and antenatal maternal smoking. Infants exposed to both risk factors had a markedly increased risk of SUDI (aOR=32.8, 95% CI=11.2, 95.8) compared with infants not exposed to either risk factor. Infants not sharing the parental bedroom were also at increased risk of SUDI (aOR=2.77, 95% CI=1.45, 5.30). Just 21 cases over the three-year study were not exposed to smoking in pregnancy, bed sharing or front or side sleeping position.

CONCLUSIONS

This study has shown that many of the risk factors that were identified in the original New Zealand Cot Death Study (1987-1989) are still relevant today. The combination of maternal smoking in pregnancy and bed sharing is extremely hazardous for infants. Furthermore, our findings indicate that the SUDI prevention messages are still applicable today and should be reinforced. SUDI mortality could be reduced to just seven p.a. in New Zealand (approximately one in 10,000 live births).

Prevalence and temporal trends of physical activity counselling in primary health care in Germany from 1997-1999 to 2008-2011

BACKGROUND

For patients, usually the first and most preferred contact person on health issues is still the doctor and most persons see their doctor at least once a year. Therefore, physical activity counselling strategies delivered by a physician seem to be a promising approach for physical activity improvement. The aim of this work is to show prevalence and time trends in physical activity counselling by primary health care physicians from 1997-1999 to 2008-2011 in Germany.

METHODS

Data from two representative cross-sectional health interview and examination surveys of the Robert Koch Institute were used. Prevalence proportions of physicians' physical activity counselling and patients' utilisation of health promotion programmes in relation to physical activity counselling were analysed. Strengths of associations were calculated by using binary logistic regression models. Overall, 11,907 persons aged 18-64 years were included in the analyses.

RESULTS

Physical activity counselling prevalence decreased from 11.1 to 9.4% in men and from 9.3 to 7.7% in women over ten years. Only persons with accumulated health risks (OR 5.33; 95% CI 1.89-15.00) and persons with diagnosed diabetes mellitus (OR 3.42; 95% CI 1.68-6.69) showed significantly higher counselling proportions in 2008-2011 compared to 1997-1999. Men were more often counselled on physical activity than women, but women showed significantly higher participation rates in physical activity promotion programmes in both surveys. In both sexes significantly higher participation rates could be observed in persons who had received some activity counselling by a physician.

CONCLUSION

Although, evidence underlines the positive health effects of regular physical activity; overall, physicians counselling behaviour on physical activity decreased over time. However, it is positive to note that a trend towards a disease-specific counselling behaviour in terms of a tailored intervention could be observed.

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

Binary file ES_Abstracts_Final_ECDC.txt matches

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, 2003–06) and adults (n = 600, 2008–10). 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): 37–45) of children and adolescents and 39% (95% CI: 34–44) of adults had seroprotective titres. The proportion of people with seroprotective titre was lowest among children younger than 10 years (15%; 95% CI: 7–30) and highest among adults aged 18 to 29 years (59%; 95% CI: 49–67). Prior influenza vaccination was associated with higher odds of having seroprotective titre (odds ratio (OR) for children and adolescents: 3.4; 95% CI: 1.8–6.5; OR for adults: 2.4; 95% CI: 1.7–3.4). 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.

Predicting poor school performance in children suspected for sleep-disordered breathing

OBJECTIVE

Habitually snoring children are at a greater risk of poor school performance (PSP). We investigated the ability of conventional sleep-disordered breathing (SDB) measures for predicting PSP in habitually snoring children.

METHODS

The dataset of Hannover Study on Sleep Apnea in Childhood (HASSAC), a large community-based study in primary school children, was retrospectively analyzed. All habitual snorers were included. Based on their grades, children were grouped into good and poor school performers. SDB measures obtained by a parental questionnaire, a home pulse oximetry, and a home polysomnography were evaluated for their accuracy in predicting poor school performance by calculating receiver operating characteristic curves and area under this curve (AUC). The most predictive single factors were identified and entered into a prediction model.

RESULTS

Of 114 habitual snorers (mean age 9.6 years, 51 boys), 59 had PSP. All investigated SDB measures showed low accuracy (ie, AUC <0.8). The highest AUC observed was 0.686 for a questionnaire score, 0.565 for an oximetry factor, and 0.624 for a polysomnography factor. Of 20 single significant predictors for PSP, five were selected for inclusion into a prediction model. The model reached an unadjusted AUC of 0.826 and an adjusted AUC of 0.851.

CONCLUSIONS

Conventional SDB measures obtained with questionnaire, oximetry, or polysomnography may not be sufficiently predictive of PSP in children suspected for SDB. However, combining factors in a clinical prediction model may improve prediction. Results of such a model may be used to assess the risk of developing neurocognitive impairment and to decide whether a child suspected for SDB might benefit from treatment.

Does breastfeeding help to reduce the risk of childhood overweight and obesity? A propensity score analysis of data from the KiGGS study

BACKGROUND

Current studies suggest that the beneficial effect of breastfeeding on overweight and obesity may have been largely overestimated. We examined the relationship between >4 months of full breastfeeding and overweight/obesity in children living in Germany.

METHODS

We analyzed retrospectively collected data on breastfeeding from children aged 3-17 years who participated in the German Health Interview and Examination Survey for Children and Adolescents (KiGGS baseline study) between 2003 and 2006 (n = 13163). To minimize confounding, we applied propensity score matching and multivariate logistic regression analyses to estimate the effect of breastfeeding on childhood overweight and obesity.

RESULTS

Adjusted analyses of the matched dataset (n = 8034) indicated that children who were breastfed for >4 months had a significant reduction in the odds of overweight (OR 0.81 [95% CI 0.71–0.92]) and obesity (OR 0.75 [95% CI 0.61–0.92]) compared to children who were not breastfed or who were breastfed for a shorter duration [corrected].Further analyses stratified by age group showed that the association was strongest in children aged 7-10 years (OR 0.67 [95% CI 0.53-0.84] for overweight and OR 0.56 [95% CI 0.39-0.81] for obesity), while no significant effect could be seen in other age groups.

DISCUSSION

Our findings support the hypothesis that breastfeeding does have a beneficial effect on childhood overweight and obesity, although the effect seems to be strongest in children of primary school age.

[The first KiGGS follow-up (KiGGS Wave 1): study conduct, sample design, and 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.

Comparing sampling strategies to recruit migrants for an epidemiological study. Results from a German feasibility study

BACKGROUND

In 2011, almost 20.0% of the population of Germany had a migration background. Studies on their health tend to have low participation rates. The aim of our study was to compare different sampling strategies and to test different approaches to recruit migrants for an epidemiological study.

METHODS

Four recruitment centres of the German National Cohort recruited persons of Turkish origin and ethnic German immigrants from former Soviet Union countries. A register-based (random samples from residents' registration offices) and a community-orientated strategy were applied. Participants underwent a medical examination and self-completed a questionnaire.

RESULTS

Used approaches: The community-orientated strategies comprised the acquisition of key persons from migrant networks to support the recruitment, invitation talks and distribution of study materials in migrant settings, etc. The identifying variables in the registry data were name, nationality or country of birth. All but one centres used bilingual study material and study staff.

PARTICIPATION

When comparing the two strategies, the register-based participation rates ranged from 10.1 to 21.0% (n = 668 participants) and the community-oriented recruitment resulted in 722 participants.

CONCLUSION

Register-based recruitment should use a combination of name, nationality and country of birth in order not to be limited to identifying persons with a foreign nationality. However, according to the study staff, the community-oriented approach involving key persons of the same cultural background leads to a better acceptance by the participants. Also, it covers a more heterogeneous group. Yet, it is time-consuming and needs considerably more staff. Further research should establish the effectiveness of a combination of both strategies.

[Prevalence of sensitisation to aeraoallergens and food allergens: results of the German Health Interview and Examination Survey for Adults (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.

Very low birth weight infants after discharge: What do parents describe?

BACKGROUND

Morbidity and mortality in Very Low Birth Weight (VLBW) infants during their hospital stay have been well described. However, there are insufficient data regarding health problems after discharge.

STUDY DESIGN

In a multicenter study performed between January 2009 and December 2010 including 2493 VLBW infants, questionnaires were sent out to all participating parents in the first year of life. We compared the parental reported health of VLBW infants with a national cohort (KIGGS).

RESULTS

The reported health of VLBW infants born after 29 weeks of gestation was identical to term infants. Even in the group of infants born before 24 weeks of gestation health was regarded as very good or good in >70% of cases. However, parents described a delayed development in >50% increasing to >70% with lower gestational age. In the first year of life VLBW infants have an increased risk of visual and hearing problems. Bronchitis was more frequent in VLBW infants but there were no differences in other infections typical for that age group. VLBW infants had less sleeping problems. No gender differences were described.

CONCLUSION

VLBW infants in our study require slightly more medical care compared to their peers. However, medical problems are relatively small compared to the developmental needs as perceived by their parents. Therefore, close follow-up and advice by specialists in infant development are needed.

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 ¼ of VLBW infants. Further studies should focus on preventing and treating gestational hypertension to avoid premature delivery and associated neonatal morbidity.

Association of breastfeeding and exposure to maternal smoking during pregnancy with children's general health status later in childhood

BACKGROUND

Maternal smoking during pregnancy is associated with a variety of risks on fetal health, whereas breastfeeding may protect infants from infections in the early postpartum period. Little has been reported regarding their associations with children's general health later in childhood.

SUBJECTS AND METHODS

Parent-rated children's general health status was investigated among 14,836 children and adolescents 3-17 years old who participated in the German Health Interview and Examination Survey for Children and Adolescents (KiGGS) in 2003-2006. Data on breastfeeding and maternal smoking during pregnancy were collected by parent-administered questionnaires. SPSS complex samples logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs).

RESULTS

Exclusive breastfeeding and non-exposure to maternal smoking during pregnancy were associated with better health status overall among all children in the KiGGS (both p<0.001). After adjusting for potential confounding factors including other prior and current exposures, exclusive breastfeeding over 6 months remained significant overall among all children (OR 1.21, 95% CI 1.05-1.38) and in the age groups 7-10 years (OR 1.27, 95% CI 1.01-1.60) and 11-17 years (OR 1.23, 95% CI 1.01-1.50), while non-exposure to maternal smoking during pregnancy remained significant in the age group 11-17 years only (OR 1.49, 95% CI 1.06-2.10).

CONCLUSIONS

Exclusive breastfeeding and non-exposure to maternal smoking during pregnancy may be associated with better children's general health status later in childhood, particularly when children reach adolescence. Further studies are required to elucidate these possible and biologically plausible associations. Health professionals should take opportunities to promote breastfeeding and cessation of smoking among (expectant) mothers for a healthy future of their children.

Prevalence and risk factors of atopic diseases in German children and adolescents

BACKGROUND

Atopic diseases became an important health problem in affluent Western societies.

METHODS

To study the prevalence and factors associated with the risk of atopic diseases in Germany, data from the German Health Interview and Examination Survey for Children and Adolescents (KiGGS) were analysed (n = 17,450). Standardized, computer-assisted personal interviews with parents and parent-administered questionnaires provided physician diagnoses of allergic rhinoconjunctivitis, atopic dermatitis and asthma as well as data on demographic characteristics, migration background, birth order, age at the beginning of nursery, atopic diseases of parents, parents' smoking status, parents' occupation, breastfeeding and living environment.

RESULTS

The life-time prevalence of atopic dermatitis was 13.2% (95% confidence limit: 12.5-13.9%), 10.7% (10.1-11.3%) for allergic rhinoconjunctivitis and 4.7% (4.3-5.1%) for asthma. At least one atopic disease in parents was the strongest factor associated with atopic diseases in the offspring, with a prevalence ratio of up to 2.6. High and middle socio-economic status (prevalence ratio, 95% confidence limit: 1.28, 1.12-1.46; 1.15, 1.01-1.32) were associated with the risk of atopic dermatitis, whereas a two-sided background of migration reduced the risk (0.76, 0.65-0.88). Factors that reduced the risk of allergic rhinoconjunctivitis were parents working as self-employed farmers (0.48, 0.30-0.76) and older siblings (0.80, 0.71-0.89), whereas the beginning of nursery school at older age was associated with an increased risk in children who were cared for outside the family before school age (1.05, 1.00-1.10). Living in mould-infested rooms (1.64, 1.23-2.19), an urban living environment (1.20, 1.02-1.42) and a smoking mother and/or father (1.20, 1.02-1.40) were associated with the risk of asthma.

CONCLUSIONS

Our results are in line with the so-called 'hygiene hypothesis', which emphasizes the role of environmental factors in addition to a genetic predisposition in the development of atopic diseases. Research on factors associated with atopic diseases can facilitate decisions on preventive strategies. Further studies are needed to explore trends in prevalence and risk factors for atopic diseases.

Perception makes the difference: the association of actual and perceived weight status with self-reported and parent-reported personal resources and well-being in adolescents

The study analyzed associations between actual weight status and weight perceptions with personal resources, physical and psychological health, as well as physical performance among adolescents (N = 5,518; age: 11-17 years). Analyses are based on data from the German Health Interview and Examination Survey for Children and Adolescents (KiGGS). Self-report measures, parental reports, as well as objective test data were considered. Results indicate that weight perceptions, rather than actual weight status, were associated with personal resources, health, and perceived physical performance. Comparing groups, we found that adolescents who felt they had "just the right weight" achieved more favourable results than those who perceived themselves as "too fat", regardless of their actual weight status. However, actual physical performance was predicted better by actual weight status. Furthermore, weight perceptions were found to mediate the link between actual weight status and all the assessed outcomes (personal resources, health, and physical performance). With respect to self-reports, the mediational effect was consistently stronger for girls, whereas the reverse was true regarding physical performance. Parental reports were not moderated by sex. Findings provide further evidence that among overweight adolescents there are subgroups that differ significantly with regard to risks and resources. Implications for practice are discussed.

[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)]

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 German Environmental Survey for Children (GerES IV): reference values and distributions for time-location patterns of German children

Children's time-location patterns are important determinants of environmental exposure and other health-relevant factors. Building on data of the German Environmental Survey for Children (GerES IV), our study aimed at deriving reference values and distributions for time-location patterns of 3-14-year-old German children. We also investigated if GerES IV data are appropriate for evaluating associations with children's health determinants by linking them to data of the National Health Interview and Examination Survey for Children and Adolescents (KiGGS). Parents reported on the time their children usually spend at home, in other indoor environments, and outdoors. This information was characterized by statistical parameters, which were also calculated for different strata concerning socio-demography and the residential environment. Consequently, group differences were evaluated by t-tests and univariate ANOVA. Reference distributions were fitted to the time-location data by a Maximum Likelihood approach to make them also useable in probabilistic exposure modeling. Finally, associations between data on the children's physical activity as well as body weight and their outdoor time were investigated by bivariate correlation analysis and cross tabulation. On daily average, German children spend 15 h and 31 min at home, 4 h and 46 min in other indoor environments, and 3 h and 43 min outdoors. Time spent at home and outdoors decreases with age while time spent in other indoor environments increases. Differences in time-location patterns were also observed for the socio-economic status (SES) and immigration status. E.g., children with a high SES spend 24 min less outdoors than low SES children. Immigrants spend on daily average 20 min more at home and 15 min less outdoors than non-immigrant children. Outdoor time was associated with parameters of the residential environment like the building development. Children living in 1- or 2-family houses spend more time outdoors than children living in building blocks (3 h 48 min vs. 3 h 29 min). Physical activity correlates with outdoor time. For children with diminished age-specific outdoor time, a higher prevalence of obesity was observed (odds ratio: 3.2, 95% CI: 1.5-7.1). GerES IV provides a compilation of current time-location reference values and distributions on German children. This data hint to substantial differences in time-location patterns within the population to be considered in environmental health risk assessment.

Reanalyses of case-control studies examining the temporal association between sudden infant death syndrome and vaccination

In this paper we examine different time periods after vaccinations and investigate whether the risk of sudden infant death is different during the post-vaccination period than at other times. Three already published case-control studies are re-examined in this context. Several evaluation approaches are presented. The recently developed self-controled case series (SCCS) method for terminal events, which only takes the cases into account, is used in addition. There is no increased or reduced risk of sudden infant death during the period after the vaccination. The previously reported protective effect seen in case contol studies is based on the inclusion of unvaccinated cases. The results of the case-control analysis of one study is affected by two confounders. The SCCS method for terminal events, in which all time-independent confounders are eliminated, is an alternative to case-control analysis when it comes to the temporal association between exposed time periods and SIDS after vaccination.