Adherence to the Dutch healthy diet index and change in glycemic control and cardiometabolic markers in people with type 2 diabetes

Purpose To investigate whether adherence to the Dutch Healthy Diet index 2015 (DHD15-index) is associated with change in glycemic control and cardio-metabolic markers over two-year follow-up in people with type 2 diabetes (T2D). Methods This prospective cohort study included 1202 individuals with T2D (mean age 68.7 +/- 9.0 years; 62.5% male; mean HbA1c 53.8 +/- 11.7 mmol/mol) from the Diabetes Care System cohort. Baseline dietary intake was assessed using a validated food frequency questionnaire, and adherence to the DHD15-index was estimated (range 0-130). HbA1c, fasting glucose, blood lipids (HDL and LDL cholesterol, cholesterol ratio), blood pressure, estimated glomerular filtration rate (eGFR), and BMI were measured at baseline, and after one- and two-year follow-up. Linear mixed model analyses were conducted to examine the associations between adherence to the DHD15-index and glycemic control and the cardio-metabolic outcomes, adjusting for energy intake, sociodemographic and lifestyle characteristics, and medication. Results Highest adherence (T3) to the DHD15-index was not associated with change in HbA1c, compared to lowest adherence (T1) [beta(T3vsT1): 0.62 mmol/mol (- 0.94; 2.19), P-trend = 0.44]. There was a non-linear association with fasting glucose, where moderate adherence (T2) was associated with a decrease in fasting glucose [beta(T2vsT1): - 0.29 mmol/L (- 0.55; - 0.03), P-trend = 0.30]. Higher adherence to the DHD15-index was associated with a decrease in BMI [beta(10point): - 0.41 kg/m(2) (- 0.60; - 0.21), P-trend < 0.001], but not with blood lipids, blood pressure or kidney function. Conclusion In this well-controlled population of people with T2D, adherence to the DHD15-index was associated with a decrease in BMI, but not with change in glycemic control or other cardio-metabolic parameters.