Digital arterial responsiveness to cold in healthy men, vibration white finger and primary Raynaud's phenomenon.

Finger systolic pressure (FSP) was measured during a standardized cold test in 291 healthy male subjects divided into five age groups. The age groups showed no difference in the change in FSP (FSP%) after cold provocation at 15 and 10 degrees C. In the entire population, the lower normal limits of FSP% were estimated as 76% at 15 degrees C and 63% at 10 degrees C. When a discriminating threshold of FSP%10 degrees < 60% was applied to the results of the cold test of 31 referents, 65 chain saw workers with or without vibration-induced white finger (VWF), and 20 male patients with primary Raynaud's phenomenon (PRP), the sensitivity of the test to detect digital vasospasm was 84% for VWF and 95% for PRP. In the chain-saw worker group, the positive and negative predictive values of the cold test were 94%. Therefore the measurement of FSP during cold provocation can be considered a useful laboratory test to confirm Raynaud's symptoms objectively in both groups and individuals.