Table 3.
Induced hyperhemia in patients with systemic sclerosis or primary Raynaud's phenomenon and healthy controls
| Healthy controls (n = 20) | Primary RP (n = 20) | SSc (n = 20) | P-value | |
| Amplitude of the thermal response (median cutaneous vascular conductance (mV/mm Hg), 10th-90th percentile) | ||||
| Baseline | 7.2 (1.1–38) | 6.4 (1.4–26.3) | 5.2 (1.2–25.9) | NS |
| 10 min thermal peak | 43.4 (23.2–63) | 42.6 (31–80.7) | 27 (14.7–51.4)a | 0.01 |
| 10–30 min thermal peak | 35.5 (12.2–55) | 37.2 (24.3–70.6) | 24.7 (13.5–51) | 0.09 |
| 44°C thermal peak | 43.1 (21.3–62.1) | 42.6 (31.6–74.3) | 25.4 (15–52.4)a | 0.01 |
| Kinetics of the thermal response (median time, seconds) | ||||
| Time to first thermal peak | 190 (125–230) | 160 (91–311) | 391 (171–1483)a | 0.0001 |
| Time to second peak | 1458 (867–1949) | 1394 (967–1991) | - | NS |
| Amplitude of the response to sublingual nitroglycerin (median vascular conductance (mV/mm Hg), 10th-90th percentile) | ||||
| Baseline | 14.1 (1.1–54.2) | 4.6 (0.8–32) | 11.5 (1.4–38) | NS |
| 4 min peak | 16.5 (1.6–55) | 9.1 (1.2–34.5) | 16.8 (3.6–37.7) | NS |
| Amplitude of the post-occlusive response (median cutaneous vascular conductance (mV/mm Hg), 10th-90th percentile) | ||||
| Baseline conductance | 13 (1.3–49) | 4.8 (1.1–32) | 7.7 (1.4–30) | NS |
| Peak hyperhemic conductance | 36.8 (11–65) | 28.5 (9.3–49) | 25.1 (9.5–50.2)b | 0.05 |
| Kinetics of the post-occlusive response (median time (seconds) 10th-90th percentile) | ||||
| Time to peak hyperhemia | 34.3 (17.4–76.5) | 44.4 (19.8–104) | 108.5 (15–287)a | 0.003 |
| Duration of hyperhemia | 165 (75–277) | 150 (97–345) | 225 (82–345) | NS |
Data are medians, with 10th and 90th percentiles in parentheses. Cutaneous blood flow is expressed as cutaneous conductance (mV/mm Hg). Local heating at 42°C was applied for 30 minutes, followed by 5 minutes heating at 44°C. The cutaneous blood conductance was measured on the left middle fingerpad. aP < 0.05 following Bonferroni's correction versus healthy controls and versus primary Raynaud's phenomenon (RP), Mann-Whitney test. bP < 0.05 following Bonferroni's correction versus healthy controls. SSc, systemic sclerosis.