The influence of maternal body mass index, maternal diabetes mellitus, and maternal smoking during pregnancy on the risk of childhood‐onset type 1 diabetes mellitus in the offspring: Systematic review and meta‐analysis of observational studies

Abstract

Summary There is emerging evidence that events occurring before and shortly after birth may be important in determining the risk of childhood‐onset type 1 diabetes mellitus (T1DM). We aimed to summarize and synthesize the associations between maternal body mass index (BMI), maternal diabetes mellitus (DM), and maternal smoking during pregnancy and the risk of childhood‐onset T1DM in the offspring by performing a systematic review and meta‐analysis of observational studies. A random effects model was used to generate the summary risk estimates. The PubMed and Web of Science databases were searched to identify relevant observational studies. Twenty one observational studies were included in the present meta‐analysis. Compared with offspring of mothers with normal weight, offspring of women with overweight or obesity were at an increased risk of developing childhood‐onset T1DM (overweight: relative risk [RR] 1.09, 95% confidence interval [CI], 1.03‐1.15; obesity: RR 1.25, 95% CI, 1.16‐1.34; per 5 kg m−2 increase in BMI: RR 1.10, 95% CI, 1.06‐1.13). No association was found for maternal underweight (RR 0.92, 95% CI, 0.75‐1.13). Maternal DM was associated with an increased risk of childhood‐onset T1DM (RR 3.26, 95% CI, 2.84‐3.74). Regarding the type of maternal DM, the greatest risk of T1DM in the offspring appeared to be conferred by maternal T1DM (RR 4.46, 95% CI, 2.89‐6.89), followed by maternal gestational diabetes mellitus (RR 1.66, 95% CI, 1.16‐2.36), and lastly by maternal type 2 diabetes mellitus (RR 1.11, 95% CI, 0.69‐1.80). Additional analysis of studies comparing maternal versus paternal T1DM within the same population revealed that offspring of fathers with T1DM had a 1.5 times higher risk of developing childhood‐onset T1DM than offspring of mothers with T1DM (RR 9.58, 95% CI, 6.33‐14.48 vs. RR 6.24, 95% CI, 5.52‐7.07). Furthermore, a reduced risk of childhood‐onset T1DM was observed in infants born to mothers who smoked during pregnancy compared with infants born to mothers who did not smoke during pregnancy (RR 0.79, 95% CI, 0.71‐0.87). In summary, our findings add further evidence that early‐life events or environmental factors may play a role in modulating infants' risk of developing T1DM later in life.

Effect of maternal smoking during pregnancy on childhood type 1 diabetes: a whole-of-population study

“…These results involve six countries (Norway, Denmark, Sweden, UK, USA and Australia) and 9872 children with type 1 diabetes, of which 16% were exposed to prenatal smoking. Our meta-analytic estimates are consistent with a recent meta-analysis [39]. However, our results are inconsistent with the HLA-matched case-control study that reported increased type 1 diabetes risk for children exposed to prenatal smoking [13].…”

Assessment of Correlations Between Neonatal Jaundice and Phototherapy With Childhood Diabetes Type 1

“…Based on the results, there was a significant association between mother's GDM and childhood type 1 diabetes. Compatible to our finding, Hidayat et al, have indicated an association between maternal gestational diabetes mellitus and increased risk of childhood T1 DM (16). Kawasaki et al, also confirmed our results.…”

Size for gestational age affects the risk for type 1 diabetes in children and adolescents: a Swedish national case–control study

“…Our finding that maternal smoking seemed to protect against type 1 diabetes is interesting and has been previously reported [36]. The mechanism is still largely unknown and requires further investigation, and there is of course always the possibility that maternal smoking is merely a confounding factor.…”