Socioeconomic Inequality in Metabolic Control Among Children With Type 1 Diabetes: A Nationwide Longitudinal Study of 4,079 Danish Children

OBJECTIVE To examine inequality in glycemic control by maternal educational level among children with type 1 diabetes in a setting with universal access to health care. RESEARCH DESIGN AND METHODS This was a longitudinal nationwide study of 4,079 Danish children with type 1 diabetes between the years 2000 and 2013. Children were divided into four groups based on mothers' education prebirth (<= high school [n = 1,643], vocational or 2-year college [n = 1,548], bachelor's degree [n = 695], >= master's degree [n = 193]). Means of socioeconomic and treatment characteristics were compared between groups. HbA(1c) and the number of daily glucose tests were compared repeatedly from onset until 5 years after onset across groups. HbA(1c) was compared across daily blood glucose testing frequency and groups. Linear regression was used to compare HbA(1c) across groups with and without adjustment for socioeconomic and treatment characteristics. RESULTS Large differences in HbA(1c) across maternal education were found. The mean level of HbA(1c) during follow-up was 59.7 mmol/mol (7.6%) for children of mothers with >= master's degrees and 68.7 mmol/mol (8.4%) for children of mothers with <= high school (difference: 9.0 mmol/mol [95% CI 7.5, 10.6]; 0.8% [95% CI 0.7, 1.0]). The associations were attenuated but remained significant after adjustment. Observable characteristics explained 41.2% of the difference in HbA(1c) between children of mothers with <= high school and mothers with >= master's degree; 22.5% of the difference was explained by more frequent blood glucose monitoring among the children with the highly educated mothers. CONCLUSIONS Family background is significantly related to outcomes for children with type 1 diabetes, even with universal access to health care.