An increasing body of research suggests that there is a close relationship between somatic symptoms (i.e., a blend of physical and psychological discomfort) and the occurrence of kinesiophobia. However, few studies have revealed how somatic symptoms influence kinesiophobia. This study constructed a sequential mediation model based on relevant theories and empirical evidence to examine the mechanism by which postesophagectomy cancer patients' somatic symptoms impact kinesiophobia. These findings indicate that somatic symptoms not only directly affect the level of kinesiophobia in postesophagectomy cancer patients but also indirectly influence patients' level of kinesiophobia through the mediating effects of intrusive rumination and avoidant coping. Three pathways of mediation were identified: ① the separate mediating effect of intrusive rumination; ② the separate mediating effect of avoidant coping; and ③ the chain-mediated effect of intrusive rumination and avoidant coping. Among these factors, the mediating effect of intrusive rumination presented the greatest magnitude.
The effect of somatic symptoms on kinesiophobia
Esophageal cancer surgery is one of the most traumatic thoracic surgery procedures, leading to issues such as decreased lung function and reduced physical activity in postoperative patients due to the effects of anesthesia, sedatives, analgesics, and muscle damage to the diaphragm and chest wall [36, 37]. With the advancement of enhanced recovery after surgery, pulmonary rehabilitation has become a critical supportive treatment during the perioperative period in thoracic surgery [38], with exercise rehabilitation being foundational [39]. This includes respiratory function exercises and early physical activities. However, postoperative somatic symptoms in esophageal cancer patients, such as pain, fatigue, dizziness, and chest tightness, can directly or indirectly restrict patients’ physical activity [40]. The results of this study indicate that somatic symptoms have a direct impact on kinesiophobia in postesophagectomy cancer patients, with the direct effect accounting for 51.38% of the total effect, thus confirming Hypothesis 1. The reasons for this may include the following: (1) somatic symptoms affect patients' self-assessment of their physical abilities, causing doubt about their current state's ability to engage in physical activities and functional exercises; and (2) due to the surgical impact, patients may experience noticeable symptoms during exercise, such as pain, dizziness, chest tightness, shortness of breath, fatigue, etc., triggering their self-protective instincts, leading them to believe that exercise could harm their bodies and thereby developing a fear of exercise. Given the direct impact of somatic symptoms on kinesiophobia, health care professionals should promptly assess and take effective measures to alleviate patients' discomfort, such as using multimodal pain relief methods to alleviate pain and oxygen therapy to relieve chest tightness. Additionally, health care providers can enhance health education and psychological care to boost patients' confidence in exercise, conduct comprehensive preexercise evaluations, and closely monitor patients during exercise to alleviate their irrational fear of physical activity. It is essential to note that patient concerns and fears about symptoms and exercise are not always excessive; appropriate concerns and fears can help prevent harm, while excessive fears can decrease patient compliance with rehabilitation. Therefore, health care providers should be attentive to distinguishing and strictly adhering to the indications and timing of physical activity and functional exercises, considering patients' tolerance, to avoid exacerbating symptoms or causing physical harm.
The mediating roles of intrusive rumination and avoidant coping
This study revealed that intrusive rumination plays a mediating role between somatic symptoms and kinesiophobia, with the mediating effect accounting for 36.15% of the total effect, thus confirming Hypothesis 2. According to the stress-rumination model, intrusive rumination focuses individuals on the negative aspects of stressful events, leading them to spend more time focusing on themselves, enhancing and maintaining event-related intrusive memories and negative emotions [41]. Patients with high levels of intrusive rumination tend to fixate on their symptom experiences, excessively focusing on the negative impacts of symptoms on themselves and engaging in behaviors that are fearful of exacerbating symptoms, specifically fearing that physical activities could worsen their physical symptoms, thereby leading to the development of fear and resistance toward physical activities and functional exercises. The study also revealed that avoidant coping acts as a mediator between somatic symptoms and kinesiophobia, with the mediating effect accounting for 8.25% of the total effect, thus confirming Hypothesis 3. Somatic symptoms are stressors that cause physical discomfort, thus promoting avoidance of thoughts and feelings related to stressful events and consequently generating resistance and fear toward physical activities or exercise. Moreover, the study revealed that intrusive rumination and avoidant coping have a chain-mediated effect on the relationship between somatic symptoms and kinesiophobia, with the mediating effect accounting for 4.22% of the total effect, thus confirming Hypothesis 4. According to response style theory, rumination is associated with individuals' deficiencies in problem-solving abilities [42]. Unpleasant somatic symptoms can trigger intrusive rumination, leading patients to linger in painful symptom experiences and repeatedly contemplate the causes and potential consequences of symptoms (e.g., "This pain makes it unbearable for me!", "Why are my symptoms so severe?", "Are these symptoms due to my poor physical recovery?") This uncontrollable cycle of intrusive thoughts traps patients, preventing them from adopting proactive strategies to address issues. Additionally, patients with high levels of intrusive rumination may magnify symptom perceptions, viewing physical activities and functional exercises as potential threats to exacerbating symptoms, doubting their own physical capabilities, and consequently developing avoidance and fear of physical activities and functional exercises, ultimately resulting in kinesiophobia. Health care professionals should pay attention to postoperative psychological health in esophageal cancer patients, actively address patients' discomfort, promptly identify patients' intrusive rumination, and take effective intervention measures. Research has shown that cognitive‒behavioral therapy [43], mindfulness-based cognitive therapy [44], acceptance and commitment therapy [45], and other methods can effectively reduce patients' levels of intrusive rumination. Moreover, guiding patients to adopt a positive and optimistic approach to dealing with their illness can lower their levels of kinesiophobia.
Limitations
This study has certain limitations. First, it employed a cross-sectional design, only exploring the current relationships between the four variables; however, symptoms in postesophagectomy cancer patients and the resultant psychological and behavioral changes dynamically evolve over time. Future research could engage in longitudinal studies to investigate the relationships between the four variables at different time points and their dynamic trends. Second, this study only surveyed postesophagectomy cancer patients from one hospital, resulting in a lack of sample representativeness. Future multicenter studies could further verify the relationships between the four variables. Third, the questionnaire data in this study were solely based on patients' self-reports, exhibiting strong subjectivity that may introduce information bias. Future studies could consider incorporating objective indicators.