Examining life-course influences on chronic disease: the importance of birth cohort studies from low- and middle- income countries. An overview

The objectives of this overview are to describe the past and potential contributions of birth cohorts to understanding chronic disease aetiology; advance a justification for the maintenance of birth cohorts from low- and middle-income countries (LMIC); provide an audit of birth cohorts from LMIC; and, finally, offer possible future directions for this sphere of research. While the contribution of birth cohorts from affluent societies to understanding disease aetiology has been considerable, we describe several reasons to anticipate why the results from such studies might not be directly applied to LMIC. More than any other developing country, Brazil has a tradition of establishing, maintaining and exploiting birth cohort studies. The clear need for a broader geographical representation may be precipitated by a greater collaboration worldwide in the sharing of ideas, fieldwork experience, and cross-country cohort data comparisons in order to carry out the best science in the most efficient manner. This requires the involvement of a central overseeing body - such as the World Health Organization - that has the respect of all countries and the capacity to develop strategic plans for `global' life-course epidemiology while addressing such issues as data-sharing. For rapid progress to be made, however, there must be minimal bureaucratic entanglements.

APOA1/C3/A4 gene cluster variability and lipid levels in Brazilian children

Genetic studies have suggested that polymorphisms of genes coding for apolipoproteins are significant determinants of serum lipoprotein and lipid levels in adults. However, only a few studies have investigated the association of these polymorphisms in children. Therefore, in the present investigation we studied the distribution of APOA1 -75 G>A, +83 C>T, APOC3 -482 C>T, -455 T>C and 3238 C>G, and APOA4 Q360H and T347S polymorphisms and their influence on plasma lipoprotein levels in children from a Brazilian northeastern admixed population. The seven polymorphic sites were genotyped in 414 children aged 5 to 15 years (mean 8.9 ± 2.9). The genotypes of the seven polymorphic sites were assessed by PCR-RFLP methods. The frequencies of the less common alleles were, in general, intermediate among parental populations, as expected. Strong linkage disequilibrium was detected between polymorphisms at the APOA1, APOC3 and APOA4 loci in this admixed population sample. Overall the genotype effects seen in adults were weaker or absent in children. The APOC3/-455 and APOA4 T347S variants showed significant effects on HDL cholesterol in girls (P = 0.033 and P = 0.016, respectively). Significantly higher plasma total (P = 0.003) and LDL cholesterol (P = 0.004) levels were observed in boys who were carriers of the 3238G allele at the APOC3/3238 C>G site. These results disclosed an overall absence of associations between these polymorphisms and lipids in children. This finding is not unexpected because expression of the effect of these polymorphisms might depend on the interaction with environmental variables both internal and external to the individual.

Tratamento da anemia ferropriva com hidróxido de ferro polimaltosado: estudo multicêntrico comparativo entre tratamento ministrado com e sem alimentaçäo concomitante

O objetivo do presente estudo foi analisar a interferência da ingestäo concomitante de alimentos, na absorçäo de ferro, em pacientes anêmicos tratados com complexo de ferro polimaltosado. Em estudo multicêntrico foram observados 113 pacientes, randomicamente alocados em dois grupos. Todos os pacientes receberam ferro polimaltosado na dose equivalente a 2,5mg de ferro elementar por dia durante 90 dias. Dos pacientes tratados 53 foram alocados no grupo C e receberam o medicamento com alimentaçäo concomitante, enquanto 60 alocados no grupo S receberam-no longe do período das refeiçöes. A avaliaçäo da eficácia foi feita por parâmetros clínicos (escores de sinais e sintomas) e laboratoriais (contagem de eritrócitos, dosagem de hemoglobina sérica, entre outros). Ao término do estudo houve melhora, estatisticamente significante, tanto nos parâmetros clínicos como nos laboratoriais, em ambos os grupos. As diferenças entre os grupos C e S, que näo eram estatisticamente significantes ao início do estudo, assim se mantiveram ao final das observaçöes. A incidência de efeitos colaterais foi muito pequena em ambos os grupos. Conclui-se que o hidróxido de ferro polimaltosado é igualmente eficiente, quer quando ministrado, quer quando ministrado sem alimento concomitante