RESUMEN
AIM: To investigate whether intensive multifactorial treatment can reverse the predisposed adverse phenotype of people with Type 2 diabetes who have a family history of diabetes. METHODS: Data from the randomized controlled trial ADDITION-Denmark were used. A total of 1441 newly diagnosed patients with diabetes (598 with family history of diabetes) were randomized to intensive treatment or routine care. Family history of diabetes was defined as having one parent and/or sibling with diabetes. Linear mixed-effects models were used to assess the changes in risk factors (BMI, waist circumference, blood pressure, lipids and HbA1c ) after 5 years of follow-up in participants with and without a family history of diabetes. An interaction term between family history of diabetes and treatment group was included in the models to test for a modifying effect of the intervention. All analyses were adjusted for age, sex, baseline value of the risk factor and general practice (random effect). RESULTS: At baseline, participants with a family history of diabetes were younger and had a 1.1 mmol/mol (0.1%) higher HbA1c concentration at the time of diagnosis than those without a family history of diabetes. Family history of diabetes modified the effect of the intervention on changes in HbA1c levels. In the group receiving routine care, participants with a family history of diabetes experienced an improvement in HbA1c concentration that was 3.3 mmol/mol (0.3%) lower than the improvement found in those without a family history of diabetes after 5 years of follow-up. In the intensive treatment group, however, there was no difference in HbA1c concentrations between participants with and without a family history of diabetes after 5 years of treatment. CONCLUSIONS: Intensive treatment of diabetes may partly remove the adverse effects of family history of diabetes on glycaemic control. The effect of this improvement on long-term diabetic complications warrants further investigation.