Dear Editor,
Among patients with chronic pain, women are greatly overrepresented, and the chronic pain syndromes with the highest prevalence overall have higher incidence in women (Neziri et al., 2011). Many studies of gender differences in acute pain sensitivity have been conducted, and, generally, when differences are observed, they almost unanimously show that women have lower tolerance to pain than men (Neziri et al., 2011). In this short letter, we would like to discuss the casual findings associated with gender-related differences in pain that we found in an experimental study we conducted on pain perception (Salmeron-Gonzalez et al., 2020).
In our study, we performed four forehead injections of 0.1 ml of physiological saline with 29-gauge needles in 100 healthy volunteers (women: n = 61; men: n = 39; average age 39.7 years +/- 13.2), applying three different analgesic methods on each fourth of the forehead (i.e., cold, lidocaine-prilocaine cream, and vibration) before injection. Sequences of infiltration and patients were randomized using simple randomization. Pain was evaluated by each subject using a Visual Analog Scale that ranged from 0 (no pain) to 10 (worst pain ever). The results of our study showed that the average pain per injection reported by men was higher (2.89 +/- 1.75) than pain reported by women (2.32 +/- 1.49). This difference was statistically significant (p < .014).
Traditional studies conducted in the field of gender-related differences in pain perception have focused on certain types of induced pain such as heat, ischemic, and pressure (Mogil, 2012). Although many theories exist to justify these findings, no consensus has been reached on the reasons for these differences. Furthermore, pain tolerance may differ depending on the type of pain evaluated (Mogil, 2012). In our study, women showed a higher pain threshold for injection pain than men.
Enrique Salmeron-Gonzalez, MD, PhD
Elena Garcia-Vilarino, MD
Alberto Sanchez-Garcia, MD
Alberto Perez-Garcia, MD, PhD
Plastic Surgeons
Department of Plastic Surgery and Microsurgery
University and Polytechnic Hospital La Fe
Valencia, Spain
REFERENCES