Do improvements in dietary behaviour contribute to cardiovascular risk factor reduction over and above cardio-protective medication in newly diagnosed diabetes patients?

BACKGROUND/OBJECTIVES:
A healthy diet is an integral component of successful diabetes management. However, the comparative importance of adopting a healthy diet for cardiovascular risk factor reduction over and above medication use among newly diagnosed diabetes patients remains unclear.
SUBJECTS/METHODS:
We computed a dietary score consistent with American Diabetes Association and Diabetes UK recommendations in 574 newly diagnosed diabetes patients by summing standardised values for the intake of total energy, saturated fat, sodium, fibre and plasma vitamin C. In linear regression analyses, stratified by cardio-protective medication use (yes/no), we quantified the comparative longitudinal associations of baseline diet and change in diet over 1 year with change in blood pressure, HbA1c and lipids.

RESULTS:
Baseline diet was generally not predictive of change in cardiovascular risk factor levels at 1 year. In contrast, dietary change over 1 year among patients prescribed and not prescribed cardio-protective medication after baseline was associated with comparative (p-interaction all ⩾0.95) reductions in diastolic blood pressure (-2.38 vs -2.93 mm Hg, respectively) and triglycerides (-0.31 vs -0.21 mmol/l, respectively), independent of potential confounding factors and change from baseline to follow-up in physical activity and smoking status.

CONCLUSIONS:
Modest dietary change over the first year following diagnosis of diabetes was associated with reductions in blood pressure and triglycerides, over and above the effects of cardio-protective medication. Our findings support the notion that dietary change should be viewed as an integral component of successful diabetes self-management, irrespective of medication use.