Table 2. Mean vascular measurements at baseline and change from baseline in 27 healthy individuals over 180 minutes on Day 1 and Day 7 of a high-nitrate (spinach) intervention or low-nitrate (asparagus) control.
| Outcome measures | Time (min) | Intervention (Day 1) | Intervention (Day 7) | ||||
|---|---|---|---|---|---|---|---|
| Low-nitrate | High-nitrate | p value | Low-nitrate | High-nitrate | p value | ||
| AI75, % | 0 | 5.70 ± 13.4 | 6.81 ± 11.0 | 0.51 | 7.88 ± 11.7 | 8.63 ± 11.9 | 0.67 |
| 60 | 0.08 ± 6.9 | - 1.94 ± 6.6 | 0.17 | - 1.16 ± 5.3 | - 3.33 ± 6.6 | 0.24 | |
| 120 | - 0.04 ± 6.5 | - 3.50 ± 8.3 | 0.07 | - 4.59 ± 7.8 | - 6.06 ± 7.4 | 0.39 | |
| 180 | - 0.82 ± 8.0 | - 6.54 ± 9.7* | 0.01 | - 4.65 ± 9.5* | - 6.93 ± 8.7* | 0.35 | |
| Central SBP, mmHg | 0 | 99.14 ± 11.9 | 98.98 ± 10.9 | 0.89 | 98.67 ± 12.5 | 99.19 ± 9.6 | 0.74 |
| 60 | - 1.40 ± 4.7 | - 0.72 ± 5.6 | 0.65 | - 0.44 ± 4.6 | - 2.45 ± 6.9 | 0.17 | |
| 120 | - 1.91 ± 5.5 | - 2.28 ± 6.9 | 0.82 | - 2.45 ± 6.4 | - 2.91 ± 6.8 | 0.75 | |
| 180 | - 1.92 ± 5.6 | - 4.38 ± 5.9* | 0.12 | - 0.66 ± 4.7 | - 4.05 ± 5.9* | < 0.01 | |
| Central DBP, mmHg | 0 | 69.52 ± 9.0 | 68.59 ± 9.1 | 0.48 | 69.07 ± 8.4 | 69.55 ± 7.4 | 0.71 |
| 60 | - 2.57 ± 5.0 | 0.31 ± 5.3 | 0.05 | - 1.78 ± 5.7 | - 1.17 ± 5.4 | 0.71 | |
| 120 | - 3.15 ± 6.0 | - 1.28 ± 6.8 | 0.28 | - 3.39 ± 4.2 | - 2.08 ± 6.1 | 0.20 | |
| 180 | - 3.13 ± 6.2* | - 2.60 ± 6.5* | 0.75 | - 1.82 ± 5.3 | - 4.43 ± 4.7* | 0.03 | |
| Brachial SBP, mmHg | 0 | 113.04 ± 12.6 | 111.94 ± 11.9 | 0.39 | 112.41 ± 13.4 | 112.67 ± 10.2 | 0.87 |
| 60 | - 2.02 ± 6.2 | - 1.78 ± 8.0 | 0.88 | 0.81 ± 6.6 | - 3.24 ± 7.1 | 0.02 | |
| 120 | - 0.57 ± 6.0 | - 2.11 ± 8.7 | 0.47 | - 2.30 ± 6.5 | - 3.22 ± 9.6 | 0.66 | |
| 180 | - 0.74 ± 7.3 | - 2.00 ± 6.6 | 0.45 | 1.39 ± 5.5 | - 2.09 ± 6.4 | 0.02 | |
| Brachial DBP, mmHg | 0 | 68.52 ± 8.4 | 67.20 ± 8.6 | 0.36 | 68.48 ± 8.4 | 68.09 ± 6.8 | 0.76 |
| 60 | - 2.07 ± 4.8 | 0.43 ± 4.9 | 0.11 | - 3.06 ± 5.9 | - 1.17 ± 5.6 | 0.28 | |
| 120 | - 2.74 ± 5.9 | - 0.74 ± 5.8 | 0.20 | - 2.89 ± 5.9 | - 2.39 ± 5.5 | 0.71 | |
| 180 | - 3.91 ± 5.5* | - 1.87 ± 6.5 | 0.21 | - 2.26 ± 6.5 | - 4.20 ± 5.3* | 0.13 | |
Values are expressed as mean ± standard deviation. Measured values at 60, 120 and 180 minutes are expressed as mean change from baseline values (0 minutes). p values are expressed as between treatments within the same day assessed by repeated measures ANOVA.
SBP: systolic blood pressure, DBP: diastolic blood pressure, AI75: augmentation index adjusted for 75 beats per minute, SD: standard deviation.
*Significantly different from baseline (p < 0.05).