Life experiences that threaten the physical or psychological integrity of individuals are extremely widespread in the general population. Based on a sample of 68,894 individuals from 24 different countries, it was estimated that 70% of them had experienced a traumatic event in their lifetime, and 30.5% had been exposed to four or more traumatic events (Benjet et al, 2016). It is estimated that the prevalence of post-traumatic stress disorder (PTSD) in the general population is 6.1% (4.1% in men and 8% in women) (Goldstein et al, 2016). Among women, the most frequently identified traumatic events are repetitive and interpersonal in nature (e.g., child abuse, gender-based violence), which are more closely associated with the later development of PTSD (Liu et al, 2017).

Exposure to traumatic events has a major impact on a person’s physical well-being (Jadhakhan et al, 2023). In this sense, Boals et al. (2013) suggest that it is not just the mere frequency of trauma symptoms that affect well-being but also the disruptive capability of these symptoms. In a study of 38,051 people from 14 countries, Scott et al. (2013) found that traumatic events are associated with pain conditions such as migraines, neck pain, and lower back pain. There are also gender-specific differences in the experience of pain, as it is observed that women suffer more frequently for chronic pain compared to men (Bimpong et al, 2022; Keogh, 2022).

Previous research points to the contribution of the phenomenon of central sensitization (CS) to the etiopathogenesis of chronic pain conditions, such as fibromyalgia, headaches, vulvodynia, and irritable bowel syndrome, among others (Yunus, 2015). CS is defined as the “increased responsiveness of nociceptive neurons in the central nervous system to normal or subthreshold afferent input” (International Association for the Study of Pain, 2011) and is associated with clinical phenomena such as hyperalgesia (increased sensitivity to pain) and allodynia (perception of pain in response to normally non-painful stimuli). Gender differences in vulnerability to CS have been identified (Smith et al, 2019) consistent with the higher risk of developing chronic pain in women (Fillingim, 2023). In addition, CS is related to traumatic events, as emotional memories associated with trauma activate the anterior cingulate cortex, which increases pain, and deactivate the dorsolateral prefrontal cortex, which decreases pain modulation (Schubiner and Betzold, 2019).

Several studies confirm the relationship between trauma/PTSD, CS, and pain. Smith et al. (2010) found that traumatic events were related to worse mental and physical health in fibromyalgia patients and that perceived stress partially mediated the effect of traumatic events on mental and physical health in this group. McKernan et al. (2019) observed in patients with chronic pain that both traumatic events and PTSD symptoms were significantly associated with clinical indicators of CS, such as pain intensity and severity. Miró et al. (2020) found that fibromyalgia patients reported higher trauma exposure than controls, along with more PTSD symptoms, many of which occurred in a significant number of cases before the diagnosis of fibromyalgia. A meta-analysis (Nanavaty et al, 2023) confirms a positive association between psychological trauma and increased pain sensitivity, a relationship moderated by CS. Likewise, a recent systematic review (Karimov-Zwienenberg et al, 2024) highlights the long-term and complex impact of cumulative childhood maltreatment on both PTSD and chronic pain in adulthood. It was also been reported that the likelihood of developing PTSD symptoms is four times higher in individuals with chronic pain compared to healthy individuals (Reyes-Pérez et al, 2020).

The comorbidity of PTSD and chronic pain has led to the formulation of several hypotheses (Otis et al, 2003), having raised the existence of a shared vulnerability and bidirectional relationships between both conditions. The shared vulnerability model (Asmundson et al, 2002) suggests that people with comorbid PTSD and chronic pain share common underlying mechanisms (e.g., anxiety sensitivity), predisposing them to develop one or both of these conditions. The mutual maintenance model (Sharp and Harvey, 2001) proposes that the cognitive, affective, and behavioral components of pain exacerbate and maintain PTSD, while the physiological, affective, and avoidance components of PTSD exacerbate and maintain pain. It has also been suggested that pain catastrophizing is a key factor in the maintenance of these syndromes, as it increases pain severity (Alschuler and Otis, 2012), and that insomnia, as well as depressive symptoms, partially mediate the relationship between PTSD and pain severity/interference (Lang et al, 2014; Morasco et al, 2013).

Understanding the relationship established between trauma/PTSD and pain is important not only in the context of CS pain conditions but also at the level of the general population. Zimmer et al. (2021) observed that exposure to war-related traumatic events was associated with poorer general health in the subsequent years. Recently, Schou-Bredal et al. (2022) documented that those women who had experienced sexual harassment had clinically significant symptoms of post-traumatic stress (25%) and also chronic pain (47.5%).

Although there is evidence on the comorbidity and mutual influence between chronic pain and PTSD, few studies have examined the gender differences in pain variables in relation to PTSD symptoms. Given the higher prevalence of chronic pain and PTSD in women, stronger relationships between these variables would be expected in women than in men. However, there does not seem to be a consensus on this matter and many of the previous studies were performed in military samples, in which comorbidity of both conditions (trauma and pain), is common. For example, in patients with chronic pain, McCall-Hosenfeld et al. (2014) examined potential mediators of the pathway between trauma exposure and somatic symptom severity, and found that in women, depression mediated the pathway, and in men, substance abuse and depression mediated the pathway, but the pathways from trauma exposure to mental health outcomes were stronger for men. In veterans with chronic pain, Hadlandsmyth et al. (2024) observed that women had higher rates of multiple overlapping pain conditions (MOPC), and although PTSD and depressive disorders were strong risk factors for MOPC, the relation between PTSD and MOPC did not differ between women and men. In veterans with chronic pain, Friedman et al. (2024) reported that PTSD symptoms were associated with higher levels of pain catastrophizing, pain intensity and pain interference, but not evidence indicating gender differences in this association were found. In veterans and military with chronic pain, MacDermid et al. (2025) found that the military sexual trauma (MST) exposures were much more common among women, but the associations of MST with severe pain and health indexes were similar across genders.

Despite previous studies, there is still limited evidence available about the relationship between trauma, CS, and pain. In order to deepen the knowledge of this issue, the present study examines the links between CS, pain experiences, and post-traumatic emotional sequelae in the Spanish general population, identifying potential divergent trends according to gender. The following hypotheses will be examined: (1) women will exhibit more intense manifestations of CS, pain, sleep disturbances, anxiety, depression, and catastrophizing than men; (2) women will report more traumatic events (mainly of interpersonal and persistent in nature) than men; (3) women will present more severe PTSD symptoms than men; (4) the presence of PTSD (Diagnostic and Statistical Manual of Mental Disorders, DSM-5; American Psychiatric Association, 2013) will be higher in women than in men; (5) women and men will exhibit a specific (and/or more prominent) correlational pattern between variables (PTSD symptoms, CS, pain, sleep, anxiety, depression, and catastrophizing); and (6) predictors of pain experiences will differ between women and men. These trends will be more pronounced in participants with central sensitization syndrome (CSS).

This study analyzed gender differences in trauma exposure, pain, and related constructs in a general Spanish population sample. Hypothesis 1 is confirmed since the results indicate that women present more exacerbated manifestations than men in all groups in pain, CS, sleep problems, anxiety, depression and pain catastrophizing, which agrees with previous research (Arias-de la Torre et al, 2021; Keogh, 2022; Meints et al, 2017; Smith et al, 2019; Zeng et al, 2020). The effect size of these differences between men and women was greater in the CSS group compared to the healthy group (in almost all variables), which could indicate that the gender differences observed in healthy population are accentuated when chronic pain develops. The CSS group presented more intense clinical symptoms than the other groups, as expected based on previous studies (Miró et al, 2012).

Regarding traumatic experiences, women reported more frequently than men (in all groups) having suffered sexual harassment/rape by an acquaintance/unknown, and psychological abuse in the intrafamily/partner relationship. They also reported having experienced more bullying/psychological abuse in the work/academic in the other pathology and healthy groups and more physical abuse in the intrafamily/partner area in the CSS and other pathology groups. So, these potentially interpersonal and ongoing events are more prevalent in women, results that agree with previous studies (Blanco et al, 2018; Liu et al, 2017) and with hypothesis 2 proposed. The CSS group suffered a greater proportion of the traumatic events mentioned; for example, in the CSS group, 23.9% of the women had been sexually harassed/raped by an acquaintance/unknown, compared to 15.1% and 13.9% of the women in the other pathology group and the healthy group, respectively. Also, noteworthy are the high percentages of men in the CSS group compared to the rest of the groups (6.1% had experienced sexual harassment/rape by an unknown; 26.5% bullying/psychological abuse at work/academic). These data agree with studies such as that of Krantz et al. (2019), who documented that people with chronic pain had higher rates of physical, sexual, and psychological abuse.

These findings suggest that women are at greater risk than men of experiencing interpersonal and prolonged trauma, along with its psychological consequences, both in the healthy population and CSS groups. On the other hand, the high percentages of these traumatic events reported by men in the CSS group stand out. Due to existing gender stereotypes, men may have greater difficulty verbalizing and sharing these experiences due to fear of stigma and the need to conform to those gender standards.

Regarding the manifestations of PTSD, greater severity was observed in women in all symptoms compared to men. These differences were significant in all symptoms except dissociative symptoms in the CSS group and in all symptoms in the healthy group. These findings are consistent with previous research (Guina et al, 2019; Miró et al, 2020) and with hypothesis 3. In addition, women also presented higher rates of PTSD diagnosis than men in all groups, in line with previous research (Kimerling et al, 2018) and with hypothesis 4. Participants with CSS had higher rates of PTSD diagnosis than the rest of the study subjects, according to previous research (Reyes-Pérez et al, 2020).

Regarding the link between pain and PTSD symptoms, there was no significant relationship in men in the CSS group (except for the dissociative symptoms with the sensory-affective of pain), but in women, all symptoms correlated significantly with the sensory-affective of pain, and all, except avoidance behaviors and interference in daily life, with pain intensity. This may indicate that the relationship between PTSD and pain is greater in women than in men in the chronic pain population. In the healthy group, all symptoms of PTSD correlated significantly with the sensory-affective of pain in women, and in men all symptoms did so except intrusive symptoms and avoidant behaviors. None of the PTSD symptoms were significantly associated with pain intensity in men in the healthy group, but in women, all symptoms were significantly associated except dissociative symptoms. This could indicate that there is no relationship between PTSD symptoms and pain intensity in men, but there is in women, both in the healthy and chronic pain population. The findings suggest that the relationship between PTSD symptoms and sensory-affective pain is similar in men and women in a healthy population, but when chronic pain develops, this link is consolidated in women while it is attenuated in men. The most relevant symptoms in this relationship, in the men, were the dissociative ones, since they presented the highest correlation in the healthy group and the only significant one in the CSS group. The results indicate a more prominent correlational pattern in women than in men, thus confirming hypothesis 5. However, it differs from the findings of previous research (Friedman et al, 2024; Hadlandsmyth et al, 2024; MacDermid et al, 2025). Note that these studies were carried out on military personal/veterans, which may constitute a group with distinct characteristics than the general population, given that military culture often emphasizes bravery and strength, which can lead to repressing/minimizing discomfort and equalize possible gender differences.

The CS was the most frequent predictor variable of pain, which supports previous research that documents the relationship between both variables (Noel et al, 2015). On the other hand, in the healthy group, dissociative symptoms were significant predictors of pain in both men and women. In this sense, it has been found that dissociative manifestations are linked to worse physical health (Panisch et al, 2022). The findings indicate that the variables that contributed to explaining the pain were partially different in women and men, so hypothesis 6 was only partially confirmed.

The present study had several limitations. The CSS group included the most common chronic pain conditions, but other disorders involving central sensitization may not have been adequately represented. The substance use/abuse, a common problem both in people with PTSD and in those with pain syndromes, was not evaluated. The cross-sectional nature of the study prevents establishing causal relationships. There may be a recall bias in self-reporting of traumatic events. Beyond the inter-rater reliability and internal consistency reported in the present study, the Interview on Traumatic Events and PTSD Symptoms does not have independent psychometric validation. The high number of women participants may limit the generalizability of gender comparisons. For future research, it would be of great interest to replicate these findings in samples from healthcare settings (e.g., rheumatology services, hospital pain units) in non-military population, and to use objective measures to assess clinical parameters (e.g., algometry for pain, polysomnography for sleep). Furthermore, to avoid perpetuating a dichotomous view of gender, studies that include the wide range of gender identities, expressions, and roles that exist in society would be necessary.

The findings of the present study suggest that women are more prone than men to all pain-related variables, whether or not they have a CSS. This differential susceptibility is likely exacerbated during the development of chronic pain. Furthermore, women are also more prone than men to traumatic events with greater psychological impact, present greater PTSD symptoms, and have higher rates of PTSD diagnosis, whether or not they have a CSS. People with CSS have higher levels of clinical symptoms, traumatic events, PTSD symptoms, and PTSD diagnoses. Finally, the relationship between PTSD symptoms and pain appears to be stronger in women than in men, which, together with the above, suggests the importance of considering trauma and its consequences in the psychological treatment of pain, especially in women. It is recommended that the treatment of chronic pain adopt a multidisciplinary and integral perspective in accordance with the clinical characteristics of each patient (Martínez et al, 2021; Sánchez et al, 2021). In this sense, understanding gender-specific differential patterns can be relevant for individualized treatment planning, and for promoting specific clinical strategies aimed at addressing the distinct needs identified in women and men.

The data are available from the corresponding author on reasonable request.

Conceptualization, MPM, AIS, and EM; Methodology, investigation and formal analysis, MPM, NP, AIS, NVA, CA, and EM; Provided supervision and assistance with the clinical interpretation of the results, MPM, AIS, and EM; Writing—original draft, MPM, NP, and EM; Writing—review and editing, MPM, NP, AIS, NVA, CA, and EM. All authors contributed to editorial changes in the manuscript. All authors read and approved the final manuscript. All authors participated sufficiently in the work and agreed to be accountable for all aspects of the work.

This study is part of a broader research project that was approved and carried out following the recommendations of the CEIM/CEI Provincial de Granada (acta 11/19) (Consejería de Salud y Familias, Junta de Andalucía), and in accordance with the Declaration of Helsinki. Informed consent was obtained from all participants included in the study.

We thank all participants for their valuable contribution to this study.

This study is part of a broader research project supported by the Spanish Ministry of Science and Innovation and Spanish State Research Agency (project PID2019-109612GB-I00, funded by MCIN/AEI/10.13039/501100011033).

The authors declare no conflict of interest.