Elevations in skin temperature of the finger as an objective index of postmenopausal hot flashes: standardization of the technique.

The present study was designed to validate and standardize a technique of continuous recording of skin temperature of the finger as an objective index of hot flashes. Significant skin temperature rises (greater than 1 degree C) were recorded in close temporal relationship to 69% of subjective hot flashes experienced by seven postmenopausal women. The temperature elevations occurred at an interval of 54 +/- 10 minutes (mean +/- standard error) and lasted an average of 31 minutes. The mean increase was 2.7 degrees +/- 0.2 degrees C. The extent of the temperature elevations found in the postmenopausal subjects was significantly greater than in premenopausal control subjects (P less than 0.05) and was reduced by estrogen treatment (P less than 0.02). This study substantiates that the recording of skin temperature changes of the finger provides an objective index of hot flashes. This should assist in the investigation of the underlying disturbance and provide more accurate evaluation of modes of therapy.