Table 2.
Microvascular measurement
| RA patients | Healthy controls | P value | |
|---|---|---|---|
| Ach-mediated vasodilatation | n = 15 | n = 15 | |
| Skin temperature, °C | 30.3 ± 0.9 | 29.9 ± 0.7 | 0.12 |
| Baseline skin perfusion, PU | 8.5 (3.7–14.5) | 6.8 (4.6–8.0) | 0.58 |
| Ach-mediated vasodilatation, % | 709 ± 454 | 797 ± 435 | 0.59 |
| SNP-mediated vasodilatation | |||
| Skin temperature, °C | 30.0 ± 0.9 | 29.8 ± 0.8 | 0.47 |
| Baseline skin perfusion, PU | 5.3 (3.6–7.3) | 6.7 (5.1–9.6) | 0.25 |
| SNP-mediated vasodilatation, % | 1,292 ± 772 | 1,094 ± 638 | 0.45 |
| Capillary recruitment | n = 14 | n = 15 | |
| Skin temperature, °C | 30.2 ± 1.4 | 29.7 ± 1.3 | 0.24 |
| Baseline capillary density, number/mm² | 49 ± 11 | 46 ± 12 | 0.57 |
| Peak capillary density, number/mm² | 66 ± 15 | 64 ± 16 | 0.80 |
| Venous occlusion, number/mm2 | 72 ± 16 | 68 ± 18 | 0.56 |
| Absolute increase, number/mm² | 17 ± 8 | 18 ± 8 | 0.79 |
| Capillary recruitment, % | 37 ± 18 | 41 ± 18 | 0.56 |
Peak capillary density was defined as the maximum number of capillaries visible directly after arterial occlusion during post-ischemic hyperaemia. Venous occlusion represents the maximal number of non-perfused capillaries exposed after venous congestion. Data are mean +/− SD or median (interquartile range). Variables were tested using Student’s t test or Mann–Whitney U test
RA rheumatoid arthritis, Ach aceltycholine, SNP sodium nitroprusside