Background: Low birth weight is related to adult-onset diabetes, although this association has been sparsely investigated in developing countries. Given reports of sexual dimorphism in fetal programming, we aimed to investigate heterogeneity, by sex and maternal diabetes, in the association of low birth weight with type 2 diabetes in participants from a large Brazilian cohort.
Methods: We used baseline (2008-2010) data of 12,066 participants aged 35-74y from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). Diabetes was defined by self-reported information and laboratory measurements (OGTT or HbA1c). We employed multivariable-adjusted Poisson regression models with robust variance to estimate prevalence ratios (PR) and 95% confidence intervals (CI).
Results: Nine hundred and ninety participants (~8% of the total) reported low birth weight (defined as <2.5 kg). Low birth weight was associated with higher prevalence of diabetes in a fully-adjusted model in women (PR 1.54, 95% CI: 1.32-1.80 vs. birth weight of 2.5-4kg), but not in men (PR 1.09, 95% CI 0.91-1.29; Pheterogeneity<0.01). Additionally, the association was stronger among participants who had mothers with diabetes (PR 1.60, 95% CI 1.33-1.93), than those who did not (PR 1.18, 95% CI 1.01-1.38; Pheterogeneity<0.05). When jointly stratified by sex and maternal diabetes, the low birth weight-diabetes association was observed for women with (PR 1.67, 95% CI 1.28-2.19) and without (PR 1.50, 95% CI 1.25-1.81) maternal diabetes. In contrast, in men, low birth weight was associated with diabetes in participants with maternal diabetes (PR 1.51, 95% CI 1.17-1.93), but not in those without (PR 0.93, 95% CI 0.74-1.18). High birth weight was marginally and homogenously associated with lower prevalence of diabetes.
Conclusions: Low birth weight was variably associated with higher prevalence of diabetes in Brazilian adults. The heterogeneity observed supports complex and sex-specific intra-uterine environmental effects on adult metabolic health.