Olsson et al. (1) describe an association between high levels of education and an increased risk of autoimmune diabetes in adults. They propose “the hygiene hypothesis” as an explanation for their results indicating that childhood environment and a low prevalence of childhood infections might contribute to the evolution of autoimmune diabetes. We would like to draw the attention to an alternative explanation of the results, and we wonder whether additional data available from the HUNT (Nord-Trøndelag Health Study) surveys might further clarify these phenomena.
Children of parents with a higher level of education are more likely to have a higher level of education themselves (2). Patients with type 1 diabetes and a higher educational social status tend to have a better metabolic control and consequently a higher conception rate and better pregnancy outcomes when compared with patients with type 1 diabetes and a lower level of education and social status (3–5). Hence, we hypothesize that parents with type 1 diabetes/latent autoimmune diabetes in adults and a higher educational level might have had a higher probability of passing the autoimmune predisposition to type 1 diabetes to their offspring compared with parents with lower levels of education. Olsson et al. seem to have adjusted the results to family history of diabetes, but apparently without differentiating between type 1 and type 2 diabetes (1). We wonder whether the data of the HUNT survey would allow such a differentiation between the types of parental diabetes and if the level of education was assessed in parents.
Acknowledgments
No potential conflicts of interest relevant to this article were reported.
