Type I diabetes among children and young adults: the role of country of birth, socioeconomic position and sex
Article first published online: 28 AUG 2012
© 2012 John Wiley & Sons A/S
Volume 14, Issue 2, pages 138–148, March 2013
How to Cite
Type I diabetes among children and young adults: the role of country of birth, socioeconomic position and sex., , , .
- Issue published online: 25 FEB 2013
- Article first published online: 28 AUG 2012
- Manuscript Accepted: 20 JUN 2012
- Manuscript Revised: 19 JUN 2012
- Manuscript Received: 11 APR 2012
- country of birth;
- socioeconomic position;
- type 1 diabetes mellitus
To investigate associations between country of birth, parental country of birth, and education with respect to incidence rate and time trends of type 1 diabetes mellitus (T1DM) among children and young adults.
We followed a nation-wide cohort of 4 469 671 males and 4 231 680 females aged 0–30 yr between 1969 and 2008. Incidence rate ratios (IRRs) with 95% confidence intervals (CIs) for T1DM were calculated using Poisson regression models. We further calculated age-standardized rates (ASRs) of T1DM, using the world population as standard.
During the study period, the ASR of T1DM increased among children younger than 15 yr, but not among young adults (15–30 yr). Compared with Swedish-born children, male and female immigrant children had 44 and 42% lower IRR of TIDM, respectively. Among offspring to immigrants, corresponding decreases in IRRs were 27 and 24%, respectively. Compared with children to parents with high education, male children to parents with low education had a 10% decreased IRR of T1DM, while no effect was observed among females. The IRR of T1DM increased with increasing age and calendar time of follow-up in both sexes (p-for trend <0.0001). In young adults, the IRR among immigrants decreased by 32% in males and 22% in females, while corresponding reductions in IRRs were less in offspring to immigrants.
We found a lower IRR of T1DM among offspring to immigrants, but especially among young immigrants compared with Sweden-born individuals. The findings show that environmental factors are important in the etiology of T1DM.