Use of dietary supplements in pregnant women in relation to sociodemographic factors - a report from The Environmental Determinants of Diabetes in the Young (TEDDY) study.

OBJECTIVES: The aim of the present study was to examine the prevalence and associated factors of dietary supplement use, particularly supplements containing vitamin D and fatty acids, in pregnant women enrolled in a multi-national study. DESIGN: The Environmental Determinants of Diabetes in the Young (TEDDY) study is a prospective longitudinal cohort study. Maternal dietary supplement use was self-reported through questionnaires at month 3 to 4 postpartum. SETTING: Six clinical research centres; three in the USA (Colorado, Georgia/Florida and Washington) and three in Europe (Sweden, Finland and Germany). SUBJECTS: Mothers (n 7326) to infants screened for high-risk HLA-DQ genotypes of type 1 diabetes. RESULTS: Ninety-two per cent of the 7326 women used one or more types of supplement during pregnancy. Vitamin D supplements were taken by 65% of the women, with the highest proportion of users in the USA (80.5 %). Overall, 16% of the women reported taking fatty acid supplements and a growing trend was seen in all countries between 2004 and 2010 (P,0.0001). The use was more common in Germany (32 %) and the USA (24 %) compared with Finland (8.5%) and Sweden (7.0 %). Being pregnant with the first child was a strong predictor for any supplement use in all countries. Low maternal age (<25 years), higher education, BMI<=25.0 kg/m2 and smoking during pregnancy were factors associated with supplement use in some but not all countries. CONCLUSIONS: The majority of the women used dietary supplements during pregnancy. The use was associated with sociodemographic and behavioural factors, such as parity, maternal age, education, BMI and maternal smoking.

Reasons for Staying as a Participant in the Environmental Determinants of Diabetes in the Young (TEDDY) Longitudinal Study.

OBJECTIVE: To assess parents' opinions about their participation in the longitudinal, multicenter study - The Environmental Determinants of Diabetes in the Young (TEDDY) consortium. METHODS: A survey was given to parents who had been in the study for ≥ 1 year. Parents rated the importance of different reasons for staying in TEDDY and how well different study components were working. Parents were also asked if they had suggestions for making TEDDY better and if they ever had thought of leaving TEDDY and if so, why. RESULTS: Out of the 3336 eligible families, 2000 completed the survey (59.1%); most (77.6%) were mothers. Survey completion was more common in European than US TEDDY sites and was associated with greater maternal education, more accurate perceptions about their child's risk of type 1 diabetes, longer participation in TEDDY and excellent attendance at TEDDY visits. "Having someone watching the child for development of T1DM" was most important reason given for staying in the study; other important reasons included "Helping science discover causes of diabetes" and "Getting child's antibody results". Most parents were very satisfied with the different components of TEDDY and had not thought of leaving the study. A minority (24%) of parents acknowledged some thoughts of leaving TEDDY and cited the blood draws, being too busy/not having enough time, the demanding protocol, and food diaries as their reasons for considering leaving. CONCLUSIONS: The study highlights factors important for successful implementation of demanding, longitudinal protocols. Friendly, devoted, skilled and knowledgeable staff with continuity makes the family comfortable. Keeping parents involved and informed on study progress is essential as is making procedures as smooth and painless as possible. Although the study is international the survey results were convergent across countries suggesting that the results have relevance to other similar studies to retain study participants.

Enrollment experiences in a pediatric longitudinal observational study: The Environmental Determinants of Diabetes in the Young (TEDDY) study.

OBJECTIVE: Our objective was to identify characteristics of infants and their families who were enrolled, refused to enroll, or were excluded from The Environmental Determinants of Diabetes in the Young (TEDDY) study. METHOD: 16,435 infants screened at birth and identified as at increased genetic risk for type 1 diabetes (T1DM) were placed into one of three categories: enrolled, excluded, or refused to enroll. Enrollment, exclusion and refusal rates were compared across countries and between infants from the general population (GP) and infants with a first degree T1DM relative (FDR). A multivariate logistic model was used to identify factors associated with TEDDY enrollment. RESULTS: TEDDY enrollment, exclusion, and refusal rates differed by country and by GP/FDR status but reasons for refusal to enroll were similar across countries and GP/FDR populations. Sweden had the highest enrollment rate, US had the highest exclusion rate, and Finland had the highest refusal rate. FDR infants were more likely to enroll than GP infants. Inability to re-contact the family was the most common reason for exclusion. Primary reasons for refusal to enroll included protocol factors (e.g. blood draws) or family factors (e.g., too busy). Study enrollment was associated with FDR status, European country of origin, older maternal age, a singleton birth, and having another child in TEDDY. CONCLUSIONS: Findings highlight the importance of country specific estimates for enrollment targets in longitudinal pediatric studies and suggest that enrollment estimates should be lowered when the study involves the general population, painful procedures, or makes multiple demands on families.