Identification of Caries Risk Determinants in Toddlers: Results of the GUSTO Birth Cohort Study.

The aim of this study was to identify risk determinants leading to early childhood caries (ECC) and visible plaque (VP) in toddlers. Data for mother-child pairs participating in the Growing Up in Singapore towards Healthy Outcomes (GUSTO) birth cohort were collected from pregnancy to toddlerhood. Oral examinations were performed in 543 children during their clinic visit at 24 months to detect ECC and VP. Following logistic regression, ECC and VP were jointly regressed as primary and secondary outcomes, respectively, using the bivariate probit model. The ECC prevalence was 17.8% at 2 years of age, with 7.3% of children having a VP score >1. ECC was associated with nighttime breastfeeding (3 weeks) and biological factors, including Indian ethnicity (lower ECC rate), higher maternal childbearing age and existing health conditions, maternal plasma folate <6 ng/mL, child BMI, and the plaque index, while VP was associated with psychobehavioral factors, including the frequency of dental visits, brushing frequency, lower parental perceived importance of baby teeth, and weaning onto solids. Interestingly, although a higher frequency of dental visits and toothbrushing were associated with lower plaque accumulation, they were associated with increased ECC risk, suggesting that these established caries-risk factors may be a consequence rather than the cause of ECC. In conclusion, Indian toddlers may be less susceptible to ECC, compared to Chinese and Malay toddlers. The study also highlights a problem-driven utilization pattern of dental services (care sought for treatment) in Singapore, in contrast to the prevention-driven approach (care sought to prevent disease) in Western countries.

Micro-techniques for analysis of human adipose tissue fatty acid composition in dietary studies.

BACKGROUND AND AIMS: Adipose tissue (AT) fatty acid (FA) composition is considered to be the gold standard long-term biomarker of dietary fatty acid intake. Typically this measurement is made directly from samples collected via large-needle-biopsy or incision. However, with growing interest in the role of AT in relation to health, ideally the fatty acid composition would be analysed along with other measurements, such as gene expression or histology, on a single AT sample. Here we assess alternative ways of obtaining AT for measuring FA composition, in some cases in conjunction with other measurements. METHODS AND RESULTS: The FA composition of tissue obtained via different methods was compared to that of tissue collected via large-needle or surgical biopsy. Fatty acid composition was not significantly different in AT collected by small-needle mini-biopsy (n = 10), from an RNA 'lipid layer' (obtained during RNA extraction, 2 sites, n = 6 for each), or from cryosectioned tissue prepared for histology (n = 10). We also assessed the usefulness of the composition of plasma NEFA as a surrogate marker of subcutaneous AT (n = 58-80). Most FAs in plasma NEFA correlated strongly with those in AT (P < 0.05). CONCLUSION: It is feasible to measure the FA composition of AT on very small amounts of tissue. Additionally, it is possible to measure FA composition on the lipid rich 'by-product' of AT samples undergoing RNA extraction for gene expression. Samples sectioned for histology are also suitable. This provides further opportunities for multidisciplinary collaborations that may lead to a better application of dietary biomarkers.

MC3R gene polymorphisms are associated with early childhood adiposity gain and infant appetite in an Asian population.

BACKGROUND: Polymorphic variants within human melanocortin-3 receptor gene (MC3R) gene have been associated with obesity. However, its influence on infancy and early childhood adiposity has not been reported before. OBJECTIVES: We assessed associations between genotype at polymorphic sites within MC3R with early childhood adiposity and interaction with early childhood appetitive traits. METHODS: We studied 1090 singletons in an Asian mother-offspring cohort genotyped for MC3R and in a subgroup (n = 422) who had completed Child Eating Behaviour Questionnaires (CEBQ) at 12 months. Children were followed from birth to 48 months, and up to 10 measurements of body mass index and five measures of triceps and subscapular skin-folds were obtained. RESULTS: Independent of potential confounders, each additional MC3R minor allele copy was associated with greater body mass index standard deviation score [B{95% confidence interval}: 0.004 units/month {0.001,0.007}; p = 0.007], triceps [0.009 mm/month {0.001,0.02}; p = 0.021] and subscapular skin-fold [0.008 mm/month {0.002,0.01}; p = 0.011] gain velocity in the first 48 months. Each additional MC3R minor allele copy was also associated with increased odds of overweight [odds ratio {95% confidence interval}: 1.48{1.17-1.88}] and obesity [1.58{1.10-2.28}] in the first 48 months. Every additional copy of MC3R minor allele was positively associated with 'slowness-in-eating' appetitive trait [0.24{0.06,0.39}, p = 0.006]; however, the relationship between 'slowness-in-eating' with adiposity gain was not statistically significant. CONCLUSIONS: Our findings support the role of MC3R genetic variants in adiposity gain during early childhood.