Equal access to health care may diminish the differences in outcome between native and immigrant patients with type 1...

Previous studies have found that ethnicity influences glycemic control. We hypothesized that differences between Nordic and non-Nordic patients are less pronounced for children with type 1 diabetes in high incidence countries in Northern Europe.

We investigated patients aged 0-15 yr in national pediatric registers in Denmark (D), Iceland (I), Norway (N), and Sweden (S) (2006-2009). Ethnic origin was defined by maternal country of birth as being Nordic or non-Nordic (other countries).

The cohort (n = 11,908, 53.0% boys, onset age 7.7 (3.9) yr, diabetes duration 6.1 (3.6) yr, [mean, (SD)]) comprised 921 (7.7%) non-Nordic patients. The frequencies of non-Nordic patients according to country of residence were: 5.7% (D), 2.7% (I), 5.5% (N), and 9.4% (S). Sex distribution and BMI z-score did not differ between Nordic and non-Nordic patients, but non-Nordic patients were 0.5 yr younger at onset than Nordic patients (p < 0.0006). Non-Nordic patients had a lower number of daily insulin bolus injections and higher daily insulin doses compared to their Nordic peers. Patients of non-Nordic origin had slightly higher HbA1c levels (0.6-2.9 mmol/mol, p < 0.001) and, with the exception of Norway, were less frequently treated with CSII (p = 0.002) after adjusting for confounders.

The reported differences in glycemic regulation between Nordic and non-Nordic type 1 diabetes children and adolescents in four Nordic countries are diminutive, but persist after accounting for treatment intensity.