Raynaud's Treatment Study (RTS)

BACKGROUND: Primary Raynaud's phenomenon is a peripheral vascular disorder resulting in vasospastic attacks provoked by cold and/or emotional stress. Attacks most often occur in the fingers, but may occur in other extremities as well. DESIGN NARRATIVE: Randomized. Patients were assigned to one of four treatment groups: slow release Nifedipine, a calcium channel blocker; pill placebo; temperature biofeedback; or electromyograph biofeedback from the frontalis muscle. The primary endpoint was reduction in number of vasospastic attacks. Other endpoints included: other measures of Raynaud's attacks including frequency, severity, duration, response to laboratory-based cold challenge, and quality of life.