Absence of breast-feeding is associated with the risk of type 1 diabetes: a case–control study in a population with rapidly increasing incidence

Abstract

There are indications that the effect of environmental factors on the risk of type 1 diabetes mellitus (T1DM) is increasing over time. This can be documented by the rapid increase of T1DM incidence in genetically stable populations. Our aim was to study an association of T1DM with the variable factors of the perinatal period and of early infancy, using data from children born over a period of changing exposure to some of the studied factors. A case-control dataset was analysed, consisting of 868 diabetic children and 1,466 anonymous controls, mostly schoolmates of the children with T1DM. The data were collected using structured questionnaires completed by parents. After performing univariate analyses, the associations were analysed using multiple logistic regression adjusted for potential confounders, including the year of birth. The risk of T1DM decreased with increasing duration of breast-feeding, while no breast-feeding was associated with an increased T1DM risk, OR=1.93 [95% CI: 1.33-2.80], breast-feeding for more than 12 months was protective, OR=0.42 [95% CI: 0.22-0.81], both being relative to the reference category of breast-feeding for 1-3 months. A short duration of day-care attendance (none or less than 1 year) was weakly associated with the risk of T1DM, OR=1.65 [95% CI: 1.05-2.62]. No association was detected between T1DM and signs of prenatal infections, perinatal stress factors, birth size and weight, indicators of crowding or the presence of a domestic pet in the household. Short breast-feeding period and short attendance to day care is associated with the risk of T1DM in Czech children.

Caesarean section is associated with an increased risk of childhood-onset type 1 diabetes mellitus: a meta-analysis of observational studies

“…The more general MEDLINE search identified a further eight articles [33][34][35][36][37][38][39][40], and review of reference lists revealed another two articles [41,42].…”

“…This observed increase in diabetes risk after Caesarean section delivery could not be explained by the confounding influence of birthweight, gestational age, maternal age, birth order, maternal diabetes or breastfeeding. Table 1 b Breast-feeding was categorised as breast-feeding at discharge from hospital [18,32], any breast-feeding [15,25,27], breast-feeding for approximately 3 months or more [30,40,43] and breast-feeding for approximately 4 months or more [37][38][39] Ref. cat., reference category…”

Why is type 1 diabetes increasing?

“…The presence of the different cytokines varied with lactation period. These data can be correlated with the protective effect observed in the study of Malcova et al (2006), where early breast-feeding was shown to provide a greater protection. Therefore, one might hypothesise that early breast milk exposure might lead to an increase in the levels of neonatal cytokines (such as IL2), which, as seen in the hygiene hypothesis, might play a role in the protective action against type 1 diabetes.…”

“…Borch-Johnsen et al (1984) introduced the theory that insufficiency in breast-feeding of genetically susceptible children may lead to the development of b-cell infection and type 1 diabetes. A variety of studies have shown an inverse correlation between a decrease in breast-feeding and the increase in type 1 diabetes risk (Borch-Johnsen et al 1984, Scott 1990, Malcova et al 2006. Human milk seems to contain several molecules and cells that help prevent infection and possibly autoimmunity.…”

Repercussions of Breastfeeding by Diabetic Women for Breast Cancer

“…Short-term breastfeeding followed by early introduction of bovine milk is a known risk factor for type 1 diabetes in infants (Gerstein and VanderMeulen, 1996). The lack of breastfeeding also increases the risk of type 1 diabetes (Malcova et al, 2006) whereas prolonged breastfeeding duration likely reduces the risk of future type 2 diabetes (Stuebe et al, 2005).…”