Research Article Fatigue, Physical Symptoms, Psychological Distress, and Use of Integrative Medicine in Patients With Advanced Cancer Caterina Calderon ,1 M. Mar Muñoz-Sa´nchez ,2 Jesu´s Peña-Lo´pez ,3 M. Helena Lo´pez-Ceballos ,4 Ana Ferna´ndez-Montes ,5 Elena Asensio-Martinez ,6 Rau´l Carrillo-Vicente ,7 Marina Gustems ,1 and Paula Jimenez-Fonseca 8 1Faculty of Psychology, University of Barcelona, Barcelona, Catalonia, Spain 2Department of Oncology, Hospital Virgen de la Luz, Cuenca, Castile-La Mancha, Spain 3Department of Oncology, Hospital Universitario La Paz Hospital General, Madrid, Community of Madrid, Spain 4Department of Oncology, Hospital Universitario Infanta So+a, San Sebastia´n de los Reyes, Community of Madrid, Spain 5Department of Oncology, Complexo Hospitalario Universitario de Ourense, Ourense, Galicia, Spain 6Department of Oncology, Hospital General Universitario de Elche, Elche, Valencian Community, Spain 7Department of Oncology, Hospital Universitario General Santa Lucia, Cartagena, Region of Murcia, Spain 8Department of Oncology, Hospital Universitario Central de Asturias, Oviedo, Asturias, Spain Correspondence should be addressed to Caterina Calderon; ccalderon@ub.edu Received 25 March 2025; Revised 8 September 2025; Accepted 17 September 2025 Guest Editor: Gabriella Pravettoni Copyright © 2025 Caterina Calderon et al. European Journal of Cancer Care published by JohnWiley & Sons Ltd.,is is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. Fatigue is a signi1cant challenge for cancer patients, substantially a2ecting their quality of life, physical symptoms, and psy- chological distress.,is study examined the relationship between fatigue in patients with advanced cancer and sociodemographic, clinical, and psychological factors. Conducted across 15 oncology departments in Spain, the study included patients with locally advanced, unresectable, or metastatic cancer eligible for systemic treatment. Participants completed the Fatigue Assessment Scale (FAS), European Organisation for Research and Treatment (EORTCQLQ-C30), Locus of Control (UWBHS), and Brief Symptom Inventory (BSI). A total of 512 patients are participated, classi1ed into low-fatigue (55%) and high-fatigue (45%) groups. High fatigue was associated with lower educational attainment (53% vs. 44%), locally advanced disease (26% vs. 17%), poorer functional status according to ECOG (70% vs. 30%), and shorter expected survival (< 18months: 51% vs. 37%). Additionally, patients with high fatigue reported greater use of integrative medicine (24% vs. 14%, p � 0.003) and higher prevalence of symptoms such as pain, nausea, and memory problems (p< 0.05). ,ey also exhibited poorer quality of life and higher psychological distress. ,ese 1ndings highlight the need to develop multidimensional strategies that address both physical symptoms and quality of life to enhance the well-being of cancer patients. Clinically, systematic screening for fatigue and psychological distress, alongside tailored supportive interventions, should be embedded in routine care to optimize outcomes in advanced cancer patients. Keywords: advanced cancer; fatigue; integrative medicine; psychological distress; quality of life 1. Introduction Fatigue is a multifaceted and widespread symptom among cancer patients, particularly those undergoing treatment for advanced cancer [1]. Cancer-related fatigue refers to a persistent sense of physical and/or mental exhaustion that limits daily functioning. It is among the most prevalent symptoms in oncology, a2ecting 40%–90% of patients during the course of illness [2, 3]. While some degree of fatigue is expected as part of the cancer experience, severe or Wiley European Journal of Cancer Care Volume 2025, Article ID 5527075, 9 pages https://doi.org/10.1155/ecc/5527075 persistent fatigue has been associated with a decreased quality of life, reduced functional capacity, and poorer treatment adherence [3, 4]. Additionally, it is linked to a higher prevalence of physical symptoms, psychological distress—including depression and anxiety—and increased utilization of healthcare services [5, 6]. ,e factors contributing to fatigue in cancer patients are diverse and multifactorial. Sociodemographic variables—age, gender, educational background, and employment—have been consistently linked to fatigue, although results remain heterogeneous [6–8]. For instance, older patients may ex- perience higher levels of fatigue due to lower physical reserve; in contrast, 1ndings regarding gender di2erences in fatigue levels remain inconclusive. While some studies suggest that women experience greater fatigue than men, possibly due to hormonal, psychological, and distress perception di2erences [9, 10], others report no signi1cant di2erences [11]. Low educational attainment and unemployment have also been associated with increased fatigue, potentially due to limited access to symptom relief resources and support systems [12]. Clinical factors such as cancer stage, functional status, and prognosis have also been investigated. Fatigue severity has also been associated with functional impairment as measured by Eastern Cooperative Oncology Group (ECOG) and with reduced life expectancy in advanced cancer [5, 9]. Symptom burden, including pain, nausea, and sleep dis- turbances, further exacerbates fatigue, creating a vicious cycle that a2ects overall well-being [3, 4]. ,ese symptoms often coexist and interact, complicating e2orts to e2ectively address fatigue in oncology settings. Psychosocial factors also play a fundamental role in fatigue among cancer patients [10]. Higher levels of psy- chological distress, including anxiety and depression, have been shown to strongly correlate with fatigue [10, 11]. Additionally, locus of control can signi1cantly inJuence the perception and management of fatigue. For instance, an external locus of control, in which the patient perceives they have no control over their situation, can exacerbate both physical and psychological symptoms by increasing feelings of helplessness and dependency while reducing motivation to cope with the situation [12, 13]. ,is perceived lack of control, combined with the absence of adequate care re- sources, may intensify fatigue, particularly in highly de- pendent patients [13, 14]. Alongside these well-established psychosocial and clinical correlates, some patients turn to integrative medi- cine practices such as acupuncture, meditation, or other complementary therapies when experiencing high levels of fatigue. Although the evidence supporting these approaches remains limited, their use may reJect patients’ e2orts to regain a sense of control and to cope with the multidi- mensional burden of symptoms [15, 16]. In the present study, we included integrative medicine as a secondary variable of interest, while maintaining our primary focus on sociodemographic, clinical, and psychological predictors of fatigue. Although fatigue has been extensively investigated in early-stage cancer, its correlates in advanced disease remain underexplored, particularly regarding the interplay of sociodemographic, clinical, and psychosocial factors. To address this gap, the present study analyzed these variables in relation to fatigue pro1les among patients with advanced cancer. In addition, it provides novel insights by examining the understudied role of integrative medicine in this population. 2. Materials and Methods 2.1. Study Design and Population. From February 2020 to May 2024, a cross-sectional study was conducted across 15 medical oncology units in various Spanish university hos- pitals. ,e study included adult patients aged 18 years or older with a histopathologically con1rmed diagnosis of unresectable advanced cancer, who were ineligible for surgical or curative interventions and were candidates for systemic anticancer treatments. Exclusion criteria encompassed individuals with phys- ical or mental conditions identi1ed by the oncologist as hindering participation. To ensure consistency, oncologists were trained through online meetings with the study co- ordinators to exclude patients whose sociodemographic or clinical circumstances could compromise their un- derstanding of the study or their ability to participate re- liably. Patients who had undergone treatment for another advanced cancer within the past 2 years, or those experi- encing signi1cant medical, social, familial, or personal challenges that could interfere with the study, were also excluded. ,is included patients with cognitive impair- ments, substantial health deterioration, or those unable to comprehend or complete the study questionnaires. Re- cruitment was conducted during the initial oncology con- sultation, during which patients were informed about their diagnosis, disease stage, and available systemic treatments. Participants who agreed to join the study provided written informed consent and received questionnaires to complete and return at their next visit. ,e study was approved by the Ethics Review Committee of each participating hospital as well as the Spanish Agency of Medicines and Health Products (AEMPS; identi1cation code: ES14042015). Participation was voluntary, anony- mous, and ensured no disruption to patients’ standard care. Out of 547 individuals initially recruited, 512 met the eli- gibility criteria. ,irty-1ve participants were excluded for various reasons: 9 did not meet the inclusion criteria, 9 met at least one exclusion criterion, and 17 provided incomplete data. 2.2. Variable Description. Sociodemographic and clinical data were collected from patients participating in the study, including sex (male or female), age (≤ 65 years or > 65 years), marital status (married or in a relationship vs. single), ed- ucational level, and employment status (unemployed or employed). Regarding clinical data, tumor location (broncho- pulmonary, colorectal, pancreas, breast, stomach, or other), histology (adenocarcinoma or other), disease stage (locally advanced or with distant metastases), type of treatment 2 European Journal of Cancer Care ejcc, 2025, 1, Downloaded from https://onlinelibrary.wiley.com/doi/10.1155/ecc/5527075 by Caterina Calderon - Spanish Cochrane National Provision (Ministerio de Sanidad) , W iley Online Library on [19/10/2025]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on W iley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License received (chemotherapy, immunotherapy, targeted func- tional therapies, or other), ECOG performance status (0 or 1 vs. 2 or higher), and estimated survival (< 18months or≥ 18months) were recorded. ,is information was uni- formly obtained from all participating hospitals as part of the study protocol. Data were managed by medical oncologists through a centralized digital platform. ,ree months after the initiation of systemic treatment, when toxicities such as fatigue are often most evident and treatment decisions are reassessed, patients were asked to complete the Fatigue Assessment Scale (FAS), the European Organisation for Research and Treatment of Cancer (EORTC QLQ-C30), the Locus of Control (UWBHS), and the Brief Symptom Inventory (BSI). In addition, they were asked whether they had used any integrative therapies and, if so, to specify the type, including homeopathy, mind–body approaches (e.g., yoga, meditation, coaching), biological therapies, body-based methods (massage, chiropractic), acupuncture, and energy-based therapies (tai chi, Reiki). Fatigue was assessed with the 10-item FAS, which covers both physical and mental aspects but has been validated as a unidimensional measure of overall fatigue [17]. Items are rated on a 5-point Likert scale (10–50 total score), with higher values indicating greater severity [18]. ,e Spanish version has shown good reliability and validity [19]. Quality of life was measured with the EORTCQLQ-C30, a widely used 30-item questionnaire in oncology. It provides three main indices: functional status (physical, role, emo- tional, social, and cognitive functioning), symptom burden (pain, fatigue, nausea, sleep problems, appetite loss, among others), and global health status. Scores are standardized from 0 to 100, with higher values reJecting better func- tioning or health, or greater symptom severity depending on the subscale. ,e questionnaire has been validated across multiple tumor types, shows strong internal consistency, requires less than 15min to complete, and has a validated Spanish version [20]. Perceived control was measured with the Locus of Control Scale (UWBHS), which captures internal versus external illness-related control beliefs [21]. Higher exter- nality scores reJect a perception that outcomes are de- termined by others or external circumstances. ,e UWBHS has been validated across diverse populations and has shown signi1cant associations with psychological outcomes [21]. Psychological distress was assessed using the BSI-18, which screens for anxiety, depression, and somatization [22]. Items are rated on a 5-point Likert scale, yielding both subscale scores and a Global Severity Index, with higher scores reJecting greater psychological distress. ,e Spanish version of the BSI has been validated for its reliability and validity [23]. 2.3. Statistical Methods. Descriptive statistics and frequency distributions were calculated to summarize demographic and clinical characteristics. A cluster analysis was performed to identify participants with similar fatigue patterns. Clus- tering variables included the fatigue items, and participants with any missing FAS scores were excluded, as this technique requires complete data for all variables. ,e k- means method was used with Euclidean distances between observations to estimate clusters, along with Ward’s hier- archical clustering method, which de1nes the distance be- tween two clusters based on the squared error criterion [24]. In all cases, distances were computed from raw data to incorporate the elevation, scatter, and shape of patients’ pro1les [25]. ,e optimal two-cluster solution was de- termined based on dendrogram inspection, silhouette index values, and clinical interpretability, distinguishing between low and high fatigue. Analyses of variance (ANOVA) and chi-square tests were conducted to examine di2erences in demographic, clinical, and psychological characteristics between the fatigue pro1les. Eta-squared ranges between 0 and 1, with η2∼0.01 indicating a small, η2∼0.06 a medium, and η2 > 0.14 a large e2ect size [25]. Statistical signi1cance was set at a p-value of < 0.05. All statistical analyses were performed using the Statistical Package for Social Sciences (SPSS) software, Version 26.0 (IBM SPSS Statistics for Windows, Armonk, NY, USA: IBM Corp.). 3. Results 3.1. Sociodemographic and Clinical Characteristics. ,e de- mographic and clinical characteristics of the 512 study participants, categorized into low fatigue (55%, n� 280) and high fatigue (45%, n� 232) groups, are summarized in Ta- ble 1. ,e cluster analysis identi1ed two distinct pro1les: a low-fatigue group (M� 21.41, SD� 2.38) and a high-fatigue group (M� 24.83, SD� 7.16). Signi1cant di2erences were identi1ed in educational level, disease stage, ECOG per- formance status, and estimated survival. Participants with lower educational attainment (primary education) were more likely to report high fatigue (53%) compared to low fatigue (44%) (p � 0.042). Similarly, those with locally ad- vanced disease showed higher levels of fatigue (26%) compared to participants with metastatic disease (17%) (p � 0.016). ECOG performance status was strongly asso- ciated with fatigue pro1les, with participants reporting high fatigue more frequently having ECOG scores of 2 or higher (70%) compared to those in the low-fatigue group (30%) (p � 0.001). Furthermore, an estimated survival of less than 18months was signi1cantly associated with high fatigue (51% vs. 37%, p � 0.001). Other variables, such as sex, age, marital status, em- ployment, tumor site, histology, and type of treatment, did not show signi1cant di2erences between fatigue groups (p> 0.05). ,ese results underscore the impact of clinical and prognostic factors on fatigue, highlighting the impor- tance of performance status and disease progression in understanding fatigue pro1les among oncology patients. 3.2. IntegrativeMedicineUse and SymptomsAmongOncology PatientsWithDi7erent Fatigue Levels. ,e use of integrative medicine and the prevalence of symptoms among the fatigue pro1les are presented in Table 2. Participants in the high- fatigue group were more likely to report the use of in- tegrative medicine (24%) compared to those in the low- European Journal of Cancer Care 3 ejcc, 2025, 1, Downloaded from https://onlinelibrary.wiley.com/doi/10.1155/ecc/5527075 by Caterina Calderon - Spanish Cochrane National Provision (Ministerio de Sanidad) , W iley Online Library on [19/10/2025]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on W iley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License fatigue group (14%) (p � 0.003). Details of the speci1c modalities are summarized in Table 3, showing that the most commonly reported practices were homeopathy (26%) and mind–body approaches such as yoga, meditation, or coaching (26%), followed by biological therapies (19%), body-based methods (15%), acupuncture (10%), and energy- based therapies such as tai chi or Reiki (4%). Symptom prevalence was notably higher among par- ticipants in the high-fatigue group across nearly all cate- gories. High fatigue was signi1cantly associated with higher rates of pain (71% vs. 44%, p � 0.001), nausea/vomiting (51% vs. 20%, p � 0.001), diarrhea (44% vs. 35%, p � 0.043), skin problems (53% vs. 39%, p � 0.001), infections (29% vs. 8%, p � 0.001), and memory issues (72% vs. 29%, p � 0.001). Other symptoms signi1cantly more common in the high-fatigue group included thyroid-related problems (21% vs. 9%, p � 0.001), sores (47% vs. 28%, p � 0.001), liver issues (32% vs. 16%, p � 0.001), kidney problems (25% vs. 11%, p � 0.001), and patient-reported scarring (63% vs. 50%, p � 0.002). A small but signi1cant di2erence was also observed in patient death rates, with a higher proportion in the high-fatigue group (6%) compared to the low-fatigue group (3%) (p � 0.042). ,ese 1ndings highlight the com- plex interplay between symptom burden and fatigue levels in oncology patients, suggesting a potential role for integrative medicine in addressing these challenges. 3.3. Psychosocial Characteristics Related to Patients’ Fatigue Pro+les. When examining the relationships between fatigue pro1les and psychosocial characteristics using the scales (EORTC, UWBHS, BSI), signi1cant di2erences were ob- served between the low-fatigue (n� 280) and high-fatigue (n� 232) groups. Participants in the high-fatigue group reported lower functional quality of life (M� 49.3 vs. Table 1: Di2erences in demographic and clinical characteristics among the fatigue pro1les (n� 512). Variable Total n (%) 512 (100%) Low fatigue n (%) 280 (55%) High fatigue n (%) 232 (45%) X2 p -value Sex Male 286 (56) 161 (57) 125 (54) 0.675 0.411 Female 226 (44) 119 (43) 107 (46) Age≤ 65 years 204 (40) 103 (37) 101 (44) 2.411 0.120> 65 years 308 (60) 177 (63) 131 (56) Marital status Married or partnered 361 (70) 191 (68) 169 (73) 1.303 0.254 Not partnered 151 (30) 89 (32) 63 (27) Educational level Primary 244 (48) 122 (44) 122 (53) 4.133 0.042 High school or more 268 (52) 158 (56) 110 (47) Employment Unemployed 298 (58) 162 (58) 137 (59) 0.075 0.785 Employed 214 (42) 118 (55) 95 (41) Tumor site Broncopulmonary 144 (28) 77 (28) 67 (29) 6.721 0.242 Colorectal 98 (19) 62 (22) 36 (16) Pancreas 50 (10) 21 (8) 28 (12) Breast 69 (14) 37 (13) 32 (14) Stomach 27 (5) 17 (6) 10 (4) Others 124 (24) 66 (24) 59 (25) Histology Adenocarcinoma 348 (68) 195 (70) 154 (66) 0.623 0.430 Others 164 (32) 85 (30) 78 (34) Stage Locally advanced 108 (21) 48 (17) 60 (26) 5.795 0.016 Dis. metastases (IV) 404 (79) 232 (83) 172 (74) Type of treatment Chemotherapy 245 (48) 130 (46) 115 (50) 1.469 0.832 Immunotherapy 32 (6) 19 (7) 13 (6) Targeted therapies 31 (6) 16 (6) 15 (7) Others 204 (40) 115 (41) 89 (38) ECOG 0 or 1 302 (59) 139 (50) 69 (30) 20.147 0.001 2 or more 210 (41) 138 (50) 158 (70) Estimated survival< 18months 208 (41) 104 (37) 119 (51) 10.333 0.001≥ 18months 296 (59) 176 (63) 113 (49) 4 European Journal of Cancer Care ejcc, 2025, 1, Downloaded from https://onlinelibrary.wiley.com/doi/10.1155/ecc/5527075 by Caterina Calderon - Spanish Cochrane National Provision (Ministerio de Sanidad) , W iley Online Library on [19/10/2025]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on W iley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License M� 72.5; η2 � 0.372), higher symptom burden (M� 38.8 vs. M� 16.8; η2 � 0.290), and worse overall health status (M� 47.3 vs. M� 57.3; η2 � 0.039). Additionally, those in the high-fatigue group scored signi1cantly lower on locus of control (M� 15.4 vs.M� 16.6; η2 � 0.018) and reported greater psychological distress (M� 70.6 vs. M� 62.4; η2 � 0.312). ,ese 1ndings highlight the considerable psychosocial disparities associated with fatigue levels in cancer patients (Table 4). 4. Discussion Fatigue is highly prevalent in oncology and has substantial consequences for daily functioning, treatment adherence, and overall quality of life [1]. ,is study explored sociodemo- graphic, clinical, and psychosocial factors associated with fatigue, classifying participants into low- and high-fatigue pro1les. ,e 1ndings partially support the inJuence of var- iables such as educational level, disease stage, functional status, and overall health. Whereas most research has focused on early-stage cancer, our study sheds light on fatigue in advanced disease, revealing distinct patterns and providing clinically meaningful contributions to an underexplored area. In this study, patients with high fatigue not only reported higher levels of psychological distress but also showed a greater tendency to use integrative medicine (24% vs. 14%). ,is suggests that while distress is a central correlate and should be addressed primarily through evidence-based psychological interventions, some patients additionally seek complementary approaches to cope with their symp- toms and improve quality of life. ,is 1nding is consistent with meta-analyses indicating that more than half of cancer patients experience fatigue, a prevalence signi1cantly higher than that observed in the general population and individuals with other diseases [26, 27]. In our study, participants with only primary education reported higher levels of fatigue compared to those with higher education. ,is aligns with previous studies, such as Schmidt et al. [28] in breast cancer, where fatigued patients had lower educational attainment, and Wang et al. [29] in colorectal cancer, which showed better fatigue management among patients with university education. ,ese 1ndings suggest that lower educational levels may limit access to or understanding of information on symptom management, exacerbating fatigue. Disease stage also inJuenced the perception of fatigue. Participants with locally advanced disease reported higher fatigue levels compared to those with metastatic disease. Although this result may seem counterintuitive, it could be explained by several factors. Patients with metastatic disease, facing a worse prognosis, may receive less aggressive pal- liative treatments and have had more time to psychologically adapt to their diagnosis and develop coping strategies. On the other hand, patients with locally advanced disease are often undergoing more active and intensive treatment, which leads to more severe side e2ects and greater un- certainty about the disease course, potentially increasing the perception of fatigue.,ese results are similar to those found by other authors, who have observed that disease progres- sion can directly inJuence the intensity of fatigue [30, 31]. ,e ECOG performance status was strongly associated with fatigue, with higher ECOG scores (≥ 2) being more Table 2: Di2erences in the use of integrative medicine in oncology among the fatigue pro1les (n� 512). Variable Total n (%) 512 (100%) Low fatigue n (%) 280 (55%) High fatigue n (%) 232 (45%) X2 p -value Medicine integrative No 407 (82) 236 (86) 171 (76) 9.014 0.003 Yes 91 (18) 37 (14) 54 (24) Symptoms Fever 70 (14) 24 (9) 46 (20) 13.502 0.001 Pain 288 (56) 123 (44) 165 (71) 37.641 0.001 Loss of appetite 276 (54) 107 (38) 169 (73) 60.675 0.001 Nausea/vomiting 175 (34) 57 (20) 118 (51) 52.095 0.001 Diarrhea 198 (39) 97 (35) 101 (44) 4.103 0.043 Skin problems 231 (45) 108 (39) 123 (53) 10.468 0.001 Infections 89 (17) 22 (8) 67 (29) 38.815 0.001 Scars 285 (56) 138 (50) 147 (63) 9.921 0.002 ,yroid 74 (15) 25 (9) 49 (21) 15.124 0.001 Sores 187 (37) 77 (28) 110 (47) 21.435 0.001 Liver 119 (23) 44 (16) 75 (32) 19.438 0.001 Kidney 88 (17) 30 (11) 58 (25) 18.037 0.001 Memory 249 (49) 82 (29) 167 (72) 91.975 0.001 Patient’s death 21 (4) 7 (3) 14 (6) 4.140 0.042 Table 3: Types and frequencies of integrative medicine modalities used by patients (n� 91). Modality n % Homeopathy 24 26 Mind–body approaches (yoga, meditation, coaching) 24 26 Biological therapies 17 19 Body-based methods (massage, chiropractic) 14 15 Acupuncture 9 10 Energy-based therapies (tai chi, Reiki) 4 4 European Journal of Cancer Care 5 ejcc, 2025, 1, Downloaded from https://onlinelibrary.wiley.com/doi/10.1155/ecc/5527075 by Caterina Calderon - Spanish Cochrane National Provision (Ministerio de Sanidad) , W iley Online Library on [19/10/2025]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on W iley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License frequent in the high-fatigue group. ,is 1nding highlights the crucial role of functional status in understanding fatigue. Patients with limited physical functioning often report greater fatigue due to the combined impact of disease burden and reduced capacity for daily activities [28, 31]. Similarly, estimated survival emerged as a signi1cant predictor, as participants with a prognosis of less than 18months re- ported higher levels of fatigue. ,is association may be linked to the psychological distress associated with a shorter life expectancy and the greater physical burden of advanced disease [29]. Fatigue is recognized as a prognostic factor in advanced cancer [32], reducing survival time by approxi- mately 39%–44% [33]. On the other hand, variables such as the type of treat- ment did not show signi1cant di2erences between fatigue pro1les in our cohort. ,is lack of association suggests that fatigue may be more strongly inJuenced by clinical and prognostic factors than by broader demographic characteristics. In our study, patients with high fatigue showed a greater tendency to use integrative medicine compared to those with low fatigue (24% vs. 14%). Among the most common practices were homeopathy and mind–body approaches, used by 26% of users. Other methods included biological therapies (19%), body-based approaches (15%), acupuncture (10%), and energy-based therapies such as tai chi or Reiki (4%). ,is increased use of integrative medicine suggests that patients with high fatigue seek complementary ap- proaches to alleviate their symptoms and improve their quality of life, aligning with existing literature on the multidimensional impact of fatigue in cancer care. Psychological interventions such as cognitive-behavioral therapy, psycho-oncological support, and mindfulness- based programs have demonstrated robust evidence in re- ducing cancer-related fatigue and distress and should be considered 1rst-line strategies. Several studies support the e2ectiveness of integrative therapies in managing fatigue, particularly in cancer patients [15, 16]. Digital interventions, such as IM@Home, have been shown to signi1cantly reduce fatigue [34], while holistic approaches like Integrated-pathy have improved quality of life and reduced cancer-related pain [35]. Additionally, mind–body therapies such as mindfulness and exercise have demonstrated bene1ts for both physical and emotional well-being [36]. However, some patients do not experience suRcient relief with these methods, underscoring the need for further research to optimize treatments and better understand individual responses [37]. Our 1ndings con1rm that fatigue is strongly associated with a higher symptom burden in cancer patients, aligning with previous studies that have identi1ed its relationship with multiple physical symptoms and systemic factors [38]. In our study, patients with high fatigue exhibited signi1- cantly higher rates of pain (71% vs. 44%), nausea/vomiting (51% vs. 20%), and memory problems (72% vs. 29%), highlighting its multidimensional impact and the need for a comprehensive approach to its management. Additionally, the higher incidence of thyroid dysfunc- tion (21% vs. 9%) and infections (29% vs. 8%) in this group suggests that fatigue may be inJuenced by systemic alter- ations a2ecting the patient’s overall health status. Likewise, mortality was higher in the high-fatigue group (6% vs. 3%), suggesting that fatigue could serve as a prognostic marker in disease progression. Recent studies also indicate that severe fatigue is linked to a higher risk of toxicity in cancer treatments, reinforcing its clinical relevance [39]. On the other hand, some studies have suggested that lifestyle-related factors, such as physical activity prior to diagnosis, may mitigate fatigue severity [38]. ,is un- derscores the importance of designing personalized in- terventions that not only address fatigue as a symptom but also consider its underlying causes and modi1able factors to improve patients’ quality of life. In our study, fatigue showed a signi1cant association with quality of life, health status, and psychological distress. Patients with high fatigue exhibited a notable reduction in functional quality of life and a higher symptom burden. Likewise, this group showed signi1cantly higher levels of psychological distress, as evidenced by elevated scores in anxiety, depression, and somatic symptoms. ,ese 1ndings align with previous studies that have identi1ed a correlation between fatigue and impairment in both physical and psychological domains, such as in hemodialysis patients, where fatigue is associated with a lower quality of life [40], and in cancer survivors, who report signi1cantly reduced quality of life when experiencing severe fatigue [41, 42]. ,ese results underscore the interconnectedness of physical and emotional well-being, suggesting that fatigue not only intensi1es symptom burden but also exacerbates psycho- logical distress and compromises overall quality of life. From Table 4: Di2erences in psychosocial characteristics and fatigue pro1les. Low fatigue n (%) 280 (55%) High fatigue n (%) 232 (45%) F p Eta-squared Mean SD Mean SD Quality of Life (EORTC) Functional scale 72.5 11.9 49.3 18.1 296.87 0.001 0.372 Symptom scale 16.8 13.1 38.8 20.6 205.25 0.001 0.290 Health status 57.3 28.5 47.3 19.7 20.18 0.001 0.039 Locus of Control (UWBHS) 16.6 4.4 15.4 3.8 9.12 0.03 0.018 Psychological distress (BSI) 62.4 5.3 70.6 6.9 228.08 0.001 0.312 Note: UWBHS, Locus of Control. Abbreviations: BSI, Brief Symptom Inventory; EORTC, European Organisation for Research and Treatment of Cancer; SD, standard deviation. 6 European Journal of Cancer Care ejcc, 2025, 1, Downloaded from https://onlinelibrary.wiley.com/doi/10.1155/ecc/5527075 by Caterina Calderon - Spanish Cochrane National Provision (Ministerio de Sanidad) , W iley Online Library on [19/10/2025]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on W iley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License a clinical perspective, this highlights the importance of systematically screening for distress in patients with high fatigue and integrating evidence-based psychological sup- port as a core component of fatigue management. 4.1. Limitations. ,is study has some limitations that should be considered when interpreting the 1ndings. First, patients with di2erent tumor types were included without making comparisons between them, limiting the generalizability of the results to speci1c metastatic neoplasms. Second, the sample consists exclusively of cancer patients in Spain, a country with universal access to public healthcare, meaning the resultsmay not be directly applicable to healthcare settings with di2erent care models and resources, particularly in non- Western countries. Another limitation is the cross-sectional design, which prevents establishing causal relationships be- tween fatigue, emotional distress, and other clinical factors, or analyzing their evolution over time. Exclusion criteria were based on clinical judgment without standardized tools, which may introduce selection bias and limit representativeness, despite investigators being trained to apply them consistently. Finally, integrative medicine use was considered only as an exploratory variable, and no causal role can be inferred. Fatigue was analyzed dichotomously using an empirical clustering approach, which, while consistent with conven- tional thresholds, inevitably reduced variability compared with continuous analyses. Assessments were also conducted 3months after treatment initiation, which may not capture trajectories detectable at other time points. Future longitu- dinal studies should explore the course of fatigue, psycho- logical distress, and quality of life and directly compare the impact of psychological interventions and complementary therapies to inform clinical practice. Despite these limitations, the study highlights signi1cant associations between fatigue severity, the use of integrative medicine, and symptom burden in cancer patients. ,e results indicate that patients with severe fatigue are more likely to turn to integrative approaches such as homeopathy, yoga, and biological therapies, suggesting a potential unmet need for complementary strategies in symptom manage- ment. Furthermore, these patients reported a signi1cantly higher prevalence of physical symptoms, including pain, nausea, and memory problems, reinforcing the multidi- mensional nature of fatigue and its impact on quality of life. 5. Conclusions From a clinical perspective, these 1ndings emphasize the importance of fatigue as a critical factor in the cancer patient experience. Systematic screening could facilitate the early identi1cation of patients at risk of a high symptom burden and allow for more personalized interventions. Given the strong association between fatigue and psychological dis- tress, evidence-based psychological support should be pri- oritized in routine care. Complementary therapies may also contribute as useful adjuncts; however, further research is warranted to establish their eRcacy, applicability, and role in alleviating symptom-related distress. Data Availability Statement ,e datasets generated and/or analyzed during the current study are not publicly available due to patient con1dentiality restrictions but are available from the corresponding author on reasonable request. Ethics Statement ,is study was conducted in accordance with the Decla- ration of Helsinki. Approval was obtained from the Research Ethics Committee of the Principality of Asturias (May 17, 2019) and by the Spanish Agency of Medicines and Medical Devices (AEMPS) (identi1cation code: L34LM-MM2GH- Y925U-RJDHQ). ,e study was observational and non- interventional. All participants provided written informed consent. Consent Please see Ethics Statement. Disclosure ,e funders had no role in the design of the study, in the collection, analysis, or interpretation of the data, or in the writing of the manuscript. Conflicts of Interest ,e authors declare no conJicts of interest. Funding ,is study was supported by the Spanish Society of Medical Oncology Foundation (FSEOM) through grants for Col- laborative Groups Projects (FSEOM2018; FSEOM2023) by AstraZeneca (AZ2020; AZ2024) and by PID2022- 137317OB-100 funded by MCIN/AEI/10.13039/ 501100011033/ and cofunded by the European Union (FEDER, “A way to make Europe”). 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