Abstract
Our previous studies have suggested that digital blood pressure response to cooling could provide a measure of the efficacy of treatments that are administered to patients with Raynaud phenomenon (RP). This method was used on 158 primary RP patients participating in a multicenter, randomized clinical trial that compared the efficacy of sustained-release nifedi-pine with temperature biofeedback in the treatment of RP. A pill placebo and electromyography served as controls. The response to local finger cooling was measured at 30°,20°,15° and 10°C in a temperature-controlled room under standardized conditions.
The results showed that, at the 15°C and 10°C local cooling temperatures, the patients in the nifedipine group had a higher mean digital systolic blood pressure, a higher relative digital systolic blood pressure (RDSP), a smaller proportion of subjects with RDSP, 70% and a smaller proportion of subjects with a zero reopening pressure than the patients in the three other treatment groups. These results were statistically significant at 10°C, the nifedipine group being significantly different from all others (p, 0.05); no significant difference was found between the three other treatment groups.