Gender differences in pressure pain threshold in a repeated measures assessment.

The objective of this study was to evaluate gender differences in the pain threshold, considering the type of pressure point, its location and the repetition of the assessment. The pressure pain threshold was evaluated in 30 healthy volunteers (12 men and 18 women) in three assessment sessions separated by 15 min and 7 days, respectively. Each assessment session was in turn composed of two trials in each of which 24 different pressure points (symmetrically located), representing the 18 tender points for the diagnosis of fibromyalgia and six control points, were assessed. Gender differences were found in the pain threshold for all of the points and the measures taken, women showing a lower pain threshold in comparison to men and being these differences more pronounced for control points than for tender points, the former reaching statistical significance in all cases. The analysis of the influence of repeated measures on gender differences in the pain threshold showed a distinct pattern of recuperation in men than in women, although only one difference in pain threshold was significant. The utility of the tender point concept to study gender differences in pain threshold and the mechanisms that may explain different patterns of recuperation between genders are discussed.