Augmentation index ( AI), brachial-ankle pulse wave velocity (baPWV) and cardio-ankle vascular index ( CAVI) are available for the assessment of arterial stiffness in clinical practices. However, influences of meal intake on these indices are still poorly understood. The aim of this study is to elucidate the effects of daily meal intake on pulse wave indices in patients with type 2 diabetes. We studied 17 patients with type 2 diabetes. AI was measured at fasting, 60 and 120 min after a commercial mixed meal (500 kcal) intake. The baPWV and CAVI were measured at fasting and 80-100 min after meal intake. All pulse indices decreased significantly after meal intake (AI, 89.3 +/- 9.7% to 77.9 +/- 9.4%, 82.0 +/- 8.4%, P<0.001; baPWV, 1652 +/- 286-1586 +/- 240 cm s(-1), P=0.002; CAVI, 9.52 +/- 0.92-9.20 +/- 0.89, P=0.037). Delta(120) (value 120 min after meal intake-fasting value) AI correlated significantly with age, body weight, Delta(120) systolic blood pressure (SBP), Delta(120) diastolic blood pressure, Delta(120) pulse pressure, Delta(120) heart rate and fasting AI. Delta (postprandial value-fasting value) baPWV correlated significantly with fasting baPWV, Delta SBP, Delta pulse pressure and HbA1c. In contrast, Delta CAVI did not correlate with any clinical variables. In conclusion, postprandial decreases in AI, baPWV and CAVI can lead to underestimate arterial stiffness in patients with type 2 diabetes. Postprandial changes in AI and baPWV, but not CAVI, are associated with changes in hemodynamic variables after daily meal intake. Hypertension Research (2010) 33, 743-747; doi: 10.1038/hr.2010.66; published online 30 April 2010