The biology of cancer-related fatigue: a review of the literature

[Immunological aspects and stress regulation in fatigue]

Fatigue is a term that describes exhaustion as either physically measurable, usually muscular, or perceived. Fatigue as a condition is observed in a wide range of long-term stresses such as chronic infectious, autoimmune, or oncologic diseases as well as mental disorders. This article provides an overview of the currently known biopsychosocial interactions between fatigue, psychosocial stress, and immune response. It describes how chronic inflammatory processes and stress interact in fatigue and for which therapeutic approaches there is evidence to date.Given the current psychoneuroimmunological knowledge and the biopsychosocial model, both high physical and psychosocial stress can converge in neuroendocrine-immunological dysregulation. According to this model, symptoms of fatigue correspond to a chronically overactivated innate immune response. At the same time, chronic immune activation favors a misactivation of the learned immune response, which is dominated by (auto)antibody production and hyperactivated T lymphocytes. However, patients who report fatigue do not necessarily display immunological dysregulations. There is currently a need for research and education in order to identify patient subpopulations and specifically tailored treatment concepts to them.

[Complementary and integrative medicine in cancer-related fatigue]

The majority of cancer patients experience fatigue during the course of their illness. Fatigue should not be seen as an inevitable consequence of cancer and its treatment. Cancer-related fatigue (CRF) is a multidimensional symptom complex that is influenced by a variety of factors. Complementary medicine approaches offer potentially promising strategies to address this fatigue and can therefore be a valuable addition to conventional therapies.In this narrative review, complementary medicine treatment approaches for tumor-associated fatigue are presented according to the historical development and current scientific evidence. The focus is on methods with the highest current evidence based on the recommendations of national and international guidelines. Therapeutic approaches from mind-body medicine, such as mindfulness-based stress reduction (MBSR), mindfulness-based cognitive therapy (MBCT), yoga, tai chi, and qigong, as well as acupuncture, acupressure, moxibustion, and phytotherapeutic treatment approaches are presented.In Germany, the complementary therapies listed here are not generally covered by health insurances. However, a few clinics have developed comprehensive programs in mind-body medicine, for which cost coverage has already been obtained. As a result, complementary medical treatments for cancer-related fatigue that adhere to national and international guidelines are typically available only as private services or within the framework of study participation.

Putting Methylphenidate for Cancer-Related Fatigue to Rest?

In the article that accompanies this editorial, Stone et al. present a randomized, double-blind, placebo-controlled trial of individually dose-titrated methylphenidate for treatment of fatigue in patients with advanced cancer, finding that methylphenidate, while safe and well-tolerated, was no more effective than placebo at relieving fatigue after 6 (±2) weeks. Future studies should consider the multifaceted nature of cancer-related fatigue, as well as the substantial placebo effects of psychostimulants, and may benefit from focusing on methylphenidate in combination with non-pharmacological interventions, or for fatigue with a predominant emotional or cognitive component.

Acupuncture influences multiple diseases by regulating gut microbiota

Acupuncture, an important green and side effect-free therapy in traditional Chinese medicine, is widely use both domestically and internationally. Acupuncture can interact with the gut microbiota and influence various diseases, including metabolic diseases, gastrointestinal diseases, mental disorders, nervous system diseases, and other diseases. This review presents a thorough analysis of these interactions and their impacts and examines the alterations in the gut microbiota and the potential clinical outcomes following acupuncture intervention to establish a basis for the future utilization of acupuncture in clinical treatments.

Effects of acupuncture on hypothalamic-pituitary-adrenal axis: Current status and future perspectives

The hypothalamic-pituitary-adrenal (HPA) axis is a critical component of the neuroendocrine system, playing a central role in regulating the body's stress response and modulating various physiological processes. Dysregulation of HPA axis function disrupts the neuroendocrine equilibrium, resulting in impaired physiological functions. Acupuncture is recognized as a non-pharmacological type of therapy which has been confirmed to play an important role in modulating the HPA axis and thus favorably targets diseases with abnormal activation of the HPA axis. With numerous studies reporting the promising efficacy of acupuncture for neuroendocrine disorders, a comprehensive review in terms of the underlying molecular mechanism for acupuncture, especially in regulating the HPA axis, is currently in need. This review fills the need and summarizes recent breakthroughs, from the basic principles and the pathological changes of HPA axis dysfunction, to the molecular mechanisms by which acupuncture regulates the HPA axis. These mechanisms include the modulation of multiple neurotransmitters and their receptors, neuropeptides and their receptors, and microRNAs in the paraventricular nucleus, hippocampus, amygdala and pituitary gland, which alleviate the hyperfunctioning of the HPA axis. This review comprehensively summarizes the mechanism of acupuncture in regulating HPA axis dysfunction for the first time, providing new targets and prospects for further exploration of acupuncture. Please cite this article as: Zheng JY, Zhu J, Wang Y, Tian ZZ. Effects of acupuncture on hypothalamic-pituitary-adrenal axis: Current status and future perspectives. J Integr Med. 2024; 22(4): 446-459.

Factors Associated With Fatigue in Persons With Atrial Fibrillation in the Atherosclerosis Risk in Communities (ARIC) Study

BACKGROUND

Atrial fibrillation (AF) is a common cardiac arrhythmia affecting over 6 million people in the U.S. Fatigue is a frequent symptom of AF, yet no underlying biological mechanisms have been identified in AF-related fatigue as in other chronic conditions such as cancer or HIV fatigue (inflammation, tissue injury). We aimed to identify biomarkers and correlates of AF-fatigue in ARIC participants.

METHODS

Participants with AF from ARIC visit 5 (2011-2013) were included in the study. Multiple linear regression was used to estimate the association of high sensitivity troponin (hs-TnT), N-terminal fragment B-type natriuretic peptide (NT-proBNP) and high sensitivity C-reactive protein (hsCRP) levels with self-reported fatigue (SF-12 and PROMIS Fatigue Scale), depressive symptoms (Center for Epidemiological Studies Depression survey), and physical functioning (Short Physical Performance Battery) scores. All biomarkers underwent natural-log transformation.

RESULTS

There were 446 participants (mean age: 78 y ± 5; 44% women). In adjusted analyses, NT-proBNP was associated with AF-fatigue (β: 0.11, 95% CI: 0.03, 0.19), increased depressive symptoms (β: 0.44, 95% CI: 0.19, 0.70), and decreased physical function (β: -0.48, 95% CI: -0.72, -0.23). Hs-TnT was also associated with elevated AF-fatigue (β: 0.24, 95% CI: 0.09, 0.39) along with decreased physical function (β: -1.19, 95% CI: -1.64, -0.75). No significant associations were found with hsCRP and fatigue.

CONCLUSION

Increased levels of cardiac injury biomarkers, depressive symptoms, and decreased physical function were associated with AF-fatigue. Inflammation was not associated with AF-fatigue; other physiological pathways, such as cardiac overload or myocardial injury may be more relevant in AF-fatigue.

The definitions, assessment, and dimensions of cancer-related fatigue: A scoping review

PURPOSE

Cancer-related fatigue (CRF) is challenging to diagnose and manage due to a lack of consensus on its definition and assessment. The objective of this scoping review is to summarize how CRF has been defined and assessed in adult patients with cancer worldwide.

METHODS

Four databases (PubMed, Embase, CINAHL Plus, PsycNet) were searched to identify eligible original research articles published in English over a 10-year span (2010-2020); CRF was required to be a primary outcome and described as a dimensional construct. Each review phase was piloted: title and abstract screening, full-text screening, and data extraction. Then, two independent reviewers participated in each review phase, and discrepancies were resolved by a third party.

RESULTS

2923 articles were screened, and 150 were included. Only 68% of articles provided a definition for CRF, of which 90% described CRF as a multidimensional construct, and 41% were identical to the National Comprehensive Cancer Network definition. Studies were primarily conducted in the United States (19%) and the majority employed longitudinal (67%), quantitative (93%), and observational (57%) study designs with sample sizes ≥ 100 people (57%). Participant age and race were often not reported (31% and 82%, respectively). The most common cancer diagnosis and treatment were breast cancer (79%) and chemotherapy (80%; n = 86), respectively. CRF measures were predominantly multidimensional (97%, n = 139), with the Multidimensional Fatigue Inventory (MFI-20) (26%) as the most common CRF measure and "Physical" (76%) as the most common CRF dimension.

CONCLUSION

This review confirms the need for a universally agreed-upon definition and standardized assessment battery for CRF.

Prevalence and biopsychosocial indicators of fatigue in cancer patients

INTRODUCTION

Symptoms of cancer-related fatigue (CRF) can have a significant impact on patients' quality of life and treatment adherence. We aimed to investigate the relationship between CRF and multiple psychosocial and somatic indicators within a large mixed cancer sample.

METHODS

In this cross-sectional study, N = 1787 outpatients with cancer were assessed for CRF, pain, anxiety, and depression using validated screening instruments. We further obtained clinical parameters (Hb, CRP, creatinine, leukocytes, ASAT, and ALAT), sociodemographic data (age, gender, income, education level, marital status, parenthood, and living area), and lifestyle factors. Multivariate linear regression models were applied to estimate the impact of each indicator on CRF.

RESULTS

Overall, 90.6% of patients experienced some CRF, with 14.8% experiencing severe CRF. No gender difference was found in the prevalence of CRF. Patients with higher levels of pain, depressive symptoms, and lower Hb levels had significantly higher levels of CRF (ps <0.001). Lower levels of CRF were observed in patients who had children (p = 0.03), had less education (p < 0.001), and were physically active for more than 2 h per week before their oncological diagnosis (p = 0.014). The latter was only a significant indicator in the male subsample.

CONCLUSION

The present results demonstrate a high prevalence of CRF and highlight that not only somatic and psychosocial factors, but also lifestyle factors prior to diagnosis appear to be associated with the etiology and persistence of CRF. To effectively treat CRF, a biopsychosocial, personalized approach is recommended.

Longitudinal associations of diurnal rest-activity rhythms with fatigue, insomnia, and health-related quality of life in survivors of colorectal cancer up to 5 years post-treatment

BACKGROUND

There is a growing population of survivors of colorectal cancer (CRC). Fatigue and insomnia are common symptoms after CRC, negatively influencing health-related quality of life (HRQoL). Besides increasing physical activity and decreasing sedentary behavior, the timing and patterns of physical activity and rest over the 24-h day (i.e. diurnal rest-activity rhythms) could also play a role in alleviating these symptoms and improving HRQoL. We investigated longitudinal associations of the diurnal rest-activity rhythm (RAR) with fatigue, insomnia, and HRQoL in survivors of CRC.

METHODS

In a prospective cohort study among survivors of stage I-III CRC, 5 repeated measurements were performed from 6 weeks up to 5 years post-treatment. Parameters of RAR, including mesor, amplitude, acrophase, circadian quotient, dichotomy index, and 24-h autocorrelation coefficient, were assessed by a custom MATLAB program using data from tri-axial accelerometers worn on the upper thigh for 7 consecutive days. Fatigue, insomnia, and HRQoL were measured by validated questionnaires. Confounder-adjusted linear mixed models were applied to analyze longitudinal associations of RAR with fatigue, insomnia, and HRQoL from 6 weeks until 5 years post-treatment. Additionally, intra-individual and inter-individual associations over time were separated.

RESULTS

Data were available from 289 survivors of CRC. All RAR parameters except for 24-h autocorrelation increased from 6 weeks to 6 months post-treatment, after which they remained relatively stable. A higher mesor, amplitude, circadian quotient, dichotomy index, and 24-h autocorrelation were statistically significantly associated with less fatigue and better HRQoL over time. A higher amplitude and circadian quotient were associated with lower insomnia. Most of these associations appeared driven by both within-person changes over time and between-person differences in RAR parameters. No significant associations were observed for acrophase.

CONCLUSIONS

In the first five years after CRC treatment, adhering to a generally more active (mesor) and consistent (24-h autocorrelation) RAR, with a pronounced peak activity (amplitude) and a marked difference between daytime and nighttime activity (dichotomy index) was found to be associated with lower fatigue, lower insomnia, and a better HRQoL. Future intervention studies are needed to investigate if restoring RAR among survivors of CRC could help to alleviate symptoms of fatigue and insomnia while enhancing their HRQoL.

TRIAL REGISTRATION

EnCoRe study NL6904 ( https://www.onderzoekmetmensen.nl/ ).

Exploring Inflammation and Stress as Biological Correlates of Symptoms in Children With Advanced Cancer: A Longitudinal Feasibility Study

Background: Few studies have examined biomarkers of stress and inflammation as underlying mechanisms of symptoms in adolescents and young adults with cancer. This study determined the feasibility of collecting blood and saliva samples across time, described the range and distribution of biomarkers, and explored the association of biomarkers with symptom adverse events (AEs). Method: This longitudinal, prospective repeated-measures single-site feasibility study recruited N  =  10 children (M = 12.5 years) receiving treatment for advanced cancer. Symptom AE data and inflammation (cytokines and C-reactive protein) and physiologic response to stress (salivary cortisol and salivary alpha-amylase) biomarker levels were collected at three time points. Descriptive statistics were used to examine feasibility and acceptability and to summarize symptom AE, stress, and inflammatory biomarker data. A linear regression model was used to determine cortisol diurnal slopes. The relationship between symptom and inflammatory biomarker data was explored and Hedges's g statistic was used to determine its effect size. Results: Participants provided 83% of saliva samples (n  =  199/240) and 185 samples were sufficient to be analyzed. Nurses collected 97% (n  =  29/30) of blood samples. Participants reported the saliva collection instructions, kits, and reminders were clear and helpful. Insomnia, pain, fatigue, and anxiety demonstrated the most medium and large negative effects with inflammatory markers. Symptom AEs demonstrated the highest number of medium and large negative effects with interleukin-8 and tumor necrosis factor-alpha (-0.53 to -2.00). Discussion: The results indicate longitudinal concurrent collection of symptom and biomarker data is feasible and inflammatory and stress biomarkers merit consideration for inclusion in future studies.

Fatigue, Toll-Like Receptor 4, and Pro-Inflammatory Cytokines in Adults With Subarachnoid Hemorrhage: A 6-Month Longitudinal Study

BACKGROUND

Fatigue is prevalent in subarachnoid hemorrhage (SAH) survivors. Biological mechanisms underlying fatigue post-SAH are not clear. Inflammation may contribute to the development of fatigue. This study aimed to examine the associations between inflammatory markers and fatigue during the first 6 months post-SAH. Specific biomarkers examined included both early and concurrent expression of Toll-Like Receptor 4 (TLR4) messenger RNA (mRNA) and plasma concentrations of pro-inflammatory cytokines, Tumor Necrosis Factor-alpha (TNF-α), Interleukin (IL)1β, and IL6.

METHODS

We conducted a 6-month longitudinal study with a convenience sample of 43 SAH survivors. We collected blood samples on days 2, 3, and 7 and 2, 3, and 6 months post-SAH to assess biomarkers. Fatigue was assessed by the PROMIS Fatigue Scale at 2, 3, and 6 months. Linear mixed models were used to test the associations between early (days 2, 3, and 7) and concurrent (2, 3, and 6 months) TLR4 mRNA expression (TagMan gene expression assays) and TNF-α, IL1β, and IL6 plasma concentrations (multiplex assays) and concurrent fatigue.

RESULTS

28% of SAH survivors experienced fatigue during the first 6 months post-SAH. Fatigue levels in SAH survivors were higher than those of the U.S. population and consistent during the 6 months. Experience of fatigue during the 6 months post-SAH was associated with higher IL1β plasma concentrations on day 7 and IL1β, IL6, and TNF-α plasma concentrations during the 6 months post-SAH.

CONCLUSION

Inflammation appears to underlie the development of fatigue in SAH survivors.

Cancer-Related Fatigue and Circulating Biomarkers in Breast Cancer Survivors

PURPOSE

Cancer-related fatigue (CRF) is the most common and disruptive symptom experienced by cancer survivors and because of its frequency and severity is especially worrisome in breast cancer survivors (BCS). Despite a great deal of research, the mechanisms underlying CRF have not been determined. The present study aims to describe associations between CRF in BCS and different blood biomarkers.

METHODS

A descriptive and cross-sectional study was conducted. A set of biomarkers assessing inflammation were measured in BCS: C-reactive protein (CRP), neutrophil-lymphocyte ratio (NLR), IL-1β, IL-6, IL-8, IL-10, tumor necrosis factor (TNF); HPA axis dysfunction (cortisol), autonomic dysfunction (noradrenaline); oxidative stress (8-OH deoxyguanosine); insulin resistance markers (insulin, IGF-I, IGFBP3) and sexual hormones (estrogens, progesterone, testosterone).

RESULTS

NLR (p = .00) and cortisol (p = .02) were positive and negatively associated with CRF, respectively. The rest of the blood markers were not associated with CRF.

CONCLUSION

Our results increase the evidence on pathophysiological mechanisms driving CRF in BCS. However, longitudinal studies are needed to explore the role of these factors as potential causal mechanisms.

Cancer-related fatigue: Towards a more targeted approach based on classification by biomarkers and psychological factors

Cancer-related fatigue is a frequent, burdensome and often insufficiently treated symptom. A more targeted treatment of fatigue is urgently needed. Therefore, we examined biomarkers and clinical factors to identify fatigue subtypes with potentially different pathophysiologies. The study population comprised disease-free breast cancer survivors of a German population-based case-control study who were re-assessed on average 6 (FU1, n = 1871) and 11 years (FU2, n = 1295) after diagnosis. At FU1 and FU2, we assessed fatigue with the 20-item multidimensional Fatigue Assessment Questionnaire and further factors by structured telephone-interviews. Serum samples collected at FU1 were analyzed for IL-1ß, IL-2, IL-4, IL-6, IL-10, TNF-a, GM-CSF, IL-5, VEGF-A, SAA, CRP, VCAM-1, ICAM-1, leptin, adiponectin and resistin. Exploratory cluster analyses among survivors with fatigue at FU1 and no history of depression yielded three clusters (CL1, CL2 and CL3). CL1 (n = 195) on average had high levels of TNF-α, IL1-β, IL-6, resistin, VEGF-A and GM-CSF, and showed high BMI and pain levels. Fatigue in CL1 manifested rather in physical dimensions. Contrarily, CL2 (n = 78) was characterized by high leptin level and had highest cognitive fatigue. CL3 (n = 318) did not show any prominent characteristics. Fatigued survivors with a history of depression (n = 214) had significantly higher physical, emotional and cognitive fatigue and showed significantly less amelioration of fatigue from FU1 to FU2 than survivors without depression. In conclusion, from the broad phenotype "cancer-related fatigue" we were able to delineate subgroups characterized by biomarkers or history of depression. Future investigations may take these subtypes into account, ultimately enabling a better targeted therapy of fatigue.

The fatigue-inducing effects of cancer and its therapy are characterized by decreased physical activity in the absence of any motivational deficit

Although cancer and its therapy are well known to be associated with fatigue, the exact nature of cancer-related fatigue remains ill-defined. We previously reported that fatigue-like behavior induced independently by tumor growth and by the chemotherapeutic agent cisplatin is characterized by reduced voluntary wheel running and an intact motivation to expand effort for food rewards. The present set of experiments was initiated to characterize the functional consequences of fatigue induced by chemoradiotherapy in tumor-bearing mice and relate them to changes in the expression of genes coding for inflammation, mitochondria dynamics and metabolism. Two syngeneic murine models of cancer were selected for this purpose, a model of human papilloma virus-related head and neck cancer and a model of lung cancer. In both models, tumor-bearing mice were submitted to chemoradiotherapy to limit tumor progression. Two dimensions of fatigue were assessed, the physical dimension by changes in physical activity in mice trained to run in wheels and the motivational dimension by changes in the performance of mice trained to nose poke to obtain a food reward in a progressive ratio schedule of food reinforcement. Chemoradiotherapy reliably decreased wheel running activity but had no effect on performance in the progressive ratio in both murine models of cancer. These effects were the same for the two murine models of cancer and did not differ according to sex. Livers and brains were collected at the end of the experiments for qRT-PCR analysis of expression of genes coding for inflammation, mitochondria dynamics, and metabolism. The observed changes were mainly apparent in the liver and typical of activation of type I interferon and NF-κB-dependent signaling, with alterations in mitochondrial dynamics and a shift toward glycolysis. Although the importance of these alterations for the pathophysiology of cancer-related fatigue remains to be explored, the present findings indicate that fatigue brought on by cancer therapy in tumor-bearing mice is more physical than motivational.

Prevalence and factors associated with cancer-related fatigue in Swiss adult survivors of childhood cancer

PURPOSE

Reported prevalence of cancer-related fatigue (CRF) among childhood cancer survivors (CCS) varies widely, and evidence on factors associated with CRF among CCS is limited. We aimed to investigate the prevalence of CRF and its associated factors among adult CCS in Switzerland.

METHODS

In a prospective cohort study, we invited adult CCS who survived at least 5 years since last cancer diagnosis, and were diagnosed when age 0-20 years and treated at Inselspital Bern between 1976 and 2015 to complete two fatigue-measuring instruments: the Checklist Individual Strength subjective fatigue subscale (CIS8R; increased fatigue 27-34, severe fatigue ≥ 35) and the numerical rating scale (NRS; moderate fatigue 4-6, severe fatigue 7-10). We collected information about previous cancer treatment and medical history, and calculated β coefficients for the association between CIS8R/NRS fatigue scores and potential determinants using multivariable linear regression.

RESULTS

We included 158 CCS (participation rate: 30%) with a median age at study of 33 years (interquartile range 26-38). Based on CIS8R, 19% (N = 30) of CCS reported increased fatigue, yet none reported severe fatigue. CRF was associated with female sex, central nervous system (CNS) tumors, sleep disturbance, and endocrine disorders. Lower CRF levels were observed among CCS age 30-39 years compared to those younger.

CONCLUSIONS

A considerable proportion of adult CCS reported increased levels of CRF.

IMPLICATIONS FOR CANCER SURVIVORS

CCS who are female and < 30 years old, have a history of CNS tumor, report sleep disturbance, or have an endocrine disorder should be screened for CRF.

Radiotherapy-induced fatigue in Palestinian breast cancer survivors

Background

No study has investigated the cancer-related fatigue (CRF) among Palestinian breast cancer survivors. Our purpose is to assess, compare, and correlate CRF in breast cancer survivors undergoing radiotherapy (RT) with study variables.

Methods

CRF in breast cancer survivors was assessed using Functional Assessment of Chronic Illness Therapy - Fatigue Scale (FACIT-F) (version 4). The sample consisted of 148 breast cancer survivors undergoing RT. Data was collected between 1 May 2021 and 1 September 2021. The means and standard deviations of the questionnaire using one-way ANOVA, and Pearson correlation coefficient were reported.

Results

Respondents ages ranged from 20 to >65 years old and was divided into four groups: (20-35, 36-50, 51-65, and >65 years, respectively). The total fatigue mean was 2.88 and the SD was 0.84, indicating an intermediate fatigue level among breast cancer survivors. Study survivors with higher education were more likely to be fatigued (F =7.68, P-value =0.001). Divorced survivors were more prone to fatigue compared to married survivors (F =5.83, P-value= 0.001). Finally, survivors who do not have children were more vulnerable to exhaustion compared to those with children (F =7.35, P-value =0.001). Also, younger survivors were more prone to fatigue, compared to older survivors (F =5.29, P-value = 0.002). Results also showed a positive relationship between each of the variables; the number of children (R =0.221, P-value =0.007), age (R =0.311, P-value =0.000), and duration of treatment (R =0.290, P-value =0.000), which means that the greater the number of children, the younger the age, or the longer the duration of treatment, the more fatigue is reported in breast cancer survivors.

Conclusions

Fatigue is frequently observed in breast cancer survivors undergoing RT. It can limit RT treatment continuity. Therefore, early detection of fatigue can help survivors adhere to RT treatment and achieve better clinical results.

Efficacy of Moxibustion for Cancer-Related Fatigue in Patients with Breast Cancer: A Systematic Review and Meta-Analysis

INTRODUCTION

Breast cancer is the most commonly diagnosed cancer worldwide, and most patients experience fatigue. However, there are no effective treatments for cancer-related fatigue (CRF). Several randomized controlled trials (RCTs) have suggested that moxibustion improves CRF. We conducted a systematic review and meta-analysis to compare the differences in fatigue scale scores, quality of life, and clinical efficacy in patients with breast cancer who developed CRF and did versus did not receive moxibustion.

METHODS

RCTs were searched in 7 databases using a standardized search method from database inception to March 2023, and RCTs that met the inclusion criteria were selected.

RESULTS

Among 1337 initially identified RCTs, 10 RCTs involving 744 participants were selected for this study. The meta-analysis involved assessment of the revised Piper Fatigue Scale scores, Cancer Fatigue Scale scores, Karnofsky Performance Scale scores, Athens Insomnia Scale scores, clinical efficacy, and Qi deficiency syndrome scale scores. Compared with the control, moxibustion was associated with significantly better Piper Fatigue Scale scores (P < 0.0001), quality of life [Karnofsky Performance Scale scores (P < 0.0001)], clinical efficacy (P = 0.0007), and Qi deficiency syndrome scale scores (P = 0.02).

CONCLUSIONS

Moxibustion improves CRF in patients with breast cancer. The efficacy of moxibustion should be further examined by high-quality studies in various countries with patients subdivided by their breast cancer treatment status.

REGISTRATION

PROSPERO ID: CRD42023451292.

Dietary Composition, Meal Timing, and Cancer-Related Fatigue: Insights From the Women's Healthy Eating and Living Study

BACKGROUND

Cancer-related fatigue is difficult to treat, and dietary interventions are promising yet underused.

OBJECTIVE

We explored associations between dietary patterns and fatigue, and the effect of a dietary intervention versus control on fatigue using Women's Healthy Eating and Living study data, plus mediators and moderators of the intervention effect.

METHODS

The Women's Healthy Eating and Living study was a randomized controlled trial among early-stage breast cancer survivors. The 4-year intervention encouraged fruits, vegetables, fiber, and 15% to 20% calories from fat. Fatigue outcomes included a 9-item energy scale and a single-item tiredness question. Dietary quality was estimated using a modified Healthy Eating Index (24-hour dietary recall) and serum carotenoid concentrations. Nutrient timing was obtained from 4-day food logs.

RESULTS

Among 2914 total participants, lower body mass index was associated with less tiredness and more energy at baseline (P < .001 for both). Earlier start and end times for daily eating windows were associated with less tiredness (P = .014 and P = .027, respectively) and greater energy (P = .006 and P = .102, respectively). The intervention did not lead to improvements in fatigue on average (P > .125). However, the intervention was more effective for participants who were younger, had fewer comorbidities, and did not have radiation treatment. Mediators included increases in serum carotenoids, increases in the modified Healthy Eating Index, and weight loss/maintenance.

CONCLUSION

Diet quality and earlier eating windows were associated with less fatigue.

IMPLICATIONS FOR PRACTICE

Programs that encourage high diet quality and a morning meal and discourage nighttime eating should be tested for efficacy in reducing cancer-related fatigue in survivorship.

Biological mechanisms of cancer-related fatigue in breast cancer survivors after treatment: a scoping review

PURPOSE

Cancer-related fatigue (CRF) is the most common symptom experienced by cancer survivors. It is a multidimensional symptom affecting physical, emotional, and/or cognitive spheres, different from other types of fatigue. Characteristically is not alleviated by sleep or rest. CRF could have specific features in breast cancer survivors (BCS), because of sex, hormones, and distinct treatments. On the other hand, more than 25% of BCS report persistent CRF for 10 years or more after the diagnosis. The present study aims to recapitulate the knowledge about the biological mechanisms that potentially drive CRF in BCS after treatment.

METHODS

To answer a broad question, a scoping review methodology was used. Data were collated from three bibliographic databases: PubMed, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL). Studies were selected if they had included more than 20 BCS, after finishing their treatment, fatigue was measured with a quantitative scale and biomarkers were analyzed.

RESULTS

The final database was composed of 1896 records. Sixty-four studies finally met the eligibility criteria. Inflammation (61%), hypothalamic-pituitary-adrenal (HPA) axis dysregulation (14%), autonomic nervous system (ANS) dysfunction (11%), and diet (9%) were the biological pathways most frequently studied. Unfortunately, results from studies about inflammation and HPA axis show many inconsistencies.

CONCLUSION

More research about the role of ANS dysfunction and diet on the pathogenesis of CRF would be warranted according to the results of the review. There are some fields such as endocannabinoid systems, mitochondrial dysfunction, gut microbiota, and oxidative stress that have been insufficiently explored.

IMPLICATIONS FOR CANCER SURVIVORS

To widen the scope of future research in the physiopathology of CRF, it is necessary to identify mechanisms that would be potentially involved and have been insufficiently explored. Because of the high prevalence of CRF in BCS and the tremendous impact that fatigue has in their quality of life, it is essential to improve the efficacy of the treatments through a good knowledge of the biological basis of CRF.

Physical activity interventions for cancer-related fatigue: A scoping review of randomized controlled trials from a Nursing Science Precision Health Model perspective

BACKGROUND

The Nursing Science Precision Health (NSPH) Model has the potential to guide research on the development, testing, and targeting of interventions.

PURPOSE

This scoping review examines the relationship between physical activity (PA) and cancer-related fatigue (CRF) within the context of the NSPH Model.

METHODS

The Joanna Briggs Institute scoping review methodology and Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guided this review. We included randomized controlled trials in people with cancer that investigated PA interventions and measured change in CRF as an outcome.

DISCUSSION

A total of 181 studies met the eligibility criteria. Over 20 different instruments were used to measure CRF. The most common PA interventions were strength training (48%), walking (36%), cycling (26%), and yoga (15%). A limited number of studies reported phenotypic characteristics (32/181, 17%) or biomarkers (31/181, 17%) associated with CRF.

CONCLUSION

This scoping review identified the body of existing research exploring CRF and PA from a precision health perspective.

Trajectories and risk factors of fatigue following colorectal cancer diagnosis

AIM

This study sought to identify groups of colorectal cancer patients based upon trajectories of fatigue and examine how demographic, clinical and behavioural risk factors differentiate these groups.

METHOD

Patients were from six cancer centres in the United States and Germany. Fatigue was measured using the fatigue subscale of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) at five time points (baseline/enrolment and 3, 6, 12 and 24 months after diagnosis). Piecewise growth mixture models identified latent trajectories of fatigue. Logistic regression models examined differences in demographic, clinical and behavioural characteristics between fatigue trajectory groups.

RESULTS

Among 1615 participants (57% men, 86% non-Hispanic White, mean age 61 ± 13 years at diagnosis), three distinct groups were identified. In the high fatigue group (36%), fatigue significantly increased in the first 6 months after diagnosis and then showed statistically and clinically significant improvement from 6 to 24 months (P values < 0.01). Throughout the study period, average fatigue met or exceeded cutoffs for clinical significance. In the moderate (34%) and low (30%) fatigue groups, fatigue levels remained below or near population norms across the study period. Patients who were diagnosed with Stage II-IV disease and/or current smokers were more likely to be in the high fatigue than in the moderate fatigue group (P values < 0.05).

CONCLUSION

A large proportion of colorectal cancer patients experienced sustained fatigue after initiation of cancer treatment. Patients with high fatigue at the time of diagnosis may benefit from early supportive care.

Beyond the symptom: the biology of fatigue

A workshop titled "Beyond the Symptom: The Biology of Fatigue" was held virtually September 27-28, 2021. It was jointly organized by the Sleep Research Society and the Neurobiology of Fatigue Working Group of the NIH Blueprint Neuroscience Research Program. For access to the presentations and video recordings, see: https://neuroscienceblueprint.nih.gov/about/event/beyond-symptom-biology-fatigue. The goals of this workshop were to bring together clinicians and scientists who use a variety of research approaches to understand fatigue in multiple conditions and to identify key gaps in our understanding of the biology of fatigue. This workshop summary distills key issues discussed in this workshop and provides a list of promising directions for future research on this topic. We do not attempt to provide a comprehensive review of the state of our understanding of fatigue, nor to provide a comprehensive reprise of the many excellent presentations. Rather, our goal is to highlight key advances and to focus on questions and future approaches to answering them.

Efficacy and safety of moxibustion on cancer-related fatigue: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

The goal of this research was to review the literature from randomized controlled trials (RCTs) on the impacts of moxibustion on cancer-related fatigue (CRF) as well as provide credible evidence to guide clinical practice.

METHODS

Three English electronic medical databases (PubMed, Embase, and the Cochrane Library) and two Chinese databases (China National Knowledge Infrastructure and Wanfang) were searched. Only randomized controlled trials on the effect of moxibustion on CRF were included in this systematic review. Study selection, data extraction, and validation were all carried out independently by two reviewers. The revised Cochrane Risk of Bias tool was used to assess the quality of the RCTs (RoB 2.0). The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was applied to assess effect sizes in individual RCTs and pooled effect sizes in meta-analyses. Data were meta-analyzed using Stata (version 14.0).

RESULTS

In a random-effects meta-analysis of 24 RCTs with 1894 participants, the aggregated standardized mean difference (SMD) revealed a statistically significant association between moxibustion and alleviation from cancer-related fatigue (SMD =  - 1.66, 95% CI =  - 2.05, - 1.28, p = 0.000). Pooled results, however, show significant heterogeneity (I2 = 92.5%), and the evidence is insufficient to determine whether this association varies systematically by measuring tools and moxibustion modalities. Furthermore, evidence ranging from very low to low showed that moxibustion had an immediate positive effect on patients with CRF.

CONCLUSION

Moxibustion may have a therapeutic effect on cancer-related fatigue. However, further large-scale, multicenter, high-quality RCTs on moxibustion for fatigue relief and safety are still needed because of the handful of studies included and the low methodological quality.

Contribution of Fatigue to Cognitive Dysfunction in Childhood Acute Lymphoblastic Leukemia Survivors

Late effects such as neurocognitive issues and fatigue have been reported in childhood acute lymphoblastic leukemia (cALL) survivors. Yet, their association is often poorly understood. In this study, we wished to (1) describe neurocognitive difficulties and fatigue in a well-characterized cohort of long-term cALL survivors and (2) explore the risk of having neurocognitive deficits as a function of fatigue. Childhood ALL survivors (N = 285) from three Canadian treatment centers completed the DIVERGT battery of cognitive tests and the PedsQL Multidimensional Fatigue Scale. We performed logistic regressions to assess the risk of a survivor to show cognitive deficits (<2.0 SD) depending on their fatigue levels. At least one cognitive deficit on the DIVERGT was present in 31% of participants. Domains primarily affected were working memory, fine motor skills, and verbal fluency. Sleep/rest fatigue in youths was higher than norms (d = 0.35). The risk for cognitive deficits increased independently with levels of fatigue in the domains of cognitive speed and flexibility, working memory, and verbal fluency. For every 10-point increase on general or sleep/rest fatigue on the 0-100 scale, there was a median +23-35% risk of showing a deficit among the 7 tasks significantly associated with fatigue. Fatigue may constitute a complementary target when searching to mitigate cognitive issues in this population.

Cisplatin decreases voluntary wheel-running activity but does not impair food-motivated behavior in mice

Cisplatin is a chemotherapeutic agent that is still commonly used to treat solid tumors. However, it has several toxic side effects due in large part to the mitochondrial damage that it induces. As this mitochondrial damage is likely to result in a decrease in the amount of metabolic energy that is available for behavioral activities, it is not surprising that fatigue develops in cancer patients treated with cisplatin. The present preclinical study was initiated to determine whether the detrimental effects of cisplatin were more pronounced on physical effort requiring a lot of energy versus effort that not only requires less energy but also procures energy in the form of food. For this purpose, mice were either trained to run in a wheel or to work for food in various schedules of food reinforcement before being treated with cisplatin. The experiments were carried out only in male mice as we had already reported that sex differences in cisplatin-induced neurotoxicities are minimal. Cisplatin was administered daily for one cycle of five days, or two cycles separated by a five-day rest. As observed in previous experiments, cisplatin drastically reduced voluntary wheel running. In contrast, when cisplatin was administered to food-restricted mice trained to work for a food reward in a progressive ratio schedule or in a fixed-interval schedule, it tended to increase the number of responses emitted to obtain the food rewards. This increase was not associated with any change in the temporal distribution of responses during the interval between two reinforcements in mice submitted to the fixed interval schedule of food reinforcement. When cisplatin was administered to food-restricted mice trained in an effort-based decision-making task in which they had to choose between working for a grain pellet with little effort and working for a preferred chocolate pellet with more effort, it decreased the total number of responses emitted to obtain food rewards. However, this effect was much less marked than the decrease in wheel running induced by cisplatin. The decrease in the effort invested in the procurement of food rewards was not associated with any change in the relative distribution of effort between low reward and high reward during the time course of the test session. These findings show that cisplatin decreases energy-consuming activities but not energy-procuring activities unless they require a choice between options differing in their cost-benefit ratio. Furthermore, they indicate that the physical dimension of fatigue is more likely to develop in cisplatin-treated individuals than the motivational dimension of fatigue.

Distinct Profiles of Morning and Evening Fatigue Co-Occurrence in Patients During Chemotherapy

BACKGROUND

Morning and evening fatigue are distinct and distressing symptoms experienced during chemotherapy that demonstrate a large amount of interindividual variability.

OBJECTIVES

The objectives of this study were to identify subgroups of patients with distinct morning and evening fatigue co-occurrence profiles and evaluate for differences among these subgroups in demographic, clinical, and symptom characteristics and quality of life.

METHODS

Oncology patients ( n = 1,334) completed the Lee Fatigue Scale to self-report morning and evening fatigue, six times over two cycles of chemotherapy. Latent profile analysis was used to identify subgroups of patients with distinct morning and evening physical fatigue profiles.

RESULTS

Four distinct morning and evening fatigue profiles were identified (i.e., Both Low, Low Morning + Moderate Evening, Both Moderate, and Both High). Compared to the Both Low profile, the Both High profile was significantly younger, less likely to be married or partnered, more likely to live alone, had a higher comorbidity burden, and lower functional status. The Both High profile had higher levels of anxiety, depressive symptoms, sleep disturbance, and pain and lower levels of quality of life.

DISCUSSION

The variability in the morning and evening severity scores among the four profiles supports the hypothesis that morning and evening fatigue are distinct but related symptoms. Clinically meaningful levels of both morning and evening fatigue were reported by 50.4% of our sample, which suggests that the co-occurrence of these two symptoms is relatively common. Patients in Both Moderate and Both High profiles experienced an extremely high symptom burden that warrants ongoing assessments and aggressive symptom management interventions.

Aqua polo: Preliminary feasibility and efficacy study of a programme of adapted, supervised water polo to reduce fatigue and improve women's psychological and social recovery after breast cancer treatment: A mixed-methods design

Physical activity has been shown to have many benefits, including reducing cancer-related fatigue (CRF) and improving psychological and physical recovery from breast cancer. Some authors have shown the benefits of aquatic practice, while others have detailed the benefits of group and supervised practice. We hypothesize that an innovative sports coaching proposal could allow a significant adherence of patients and contribute to their health improvement. The main objective is to study the feasibility of an adapted water polo programme (aqua polo) for women after breast cancer. Secondarily we will analyse the effect of such a practice on patients' recovery and study the relationship between coaches and participants. The use of mixed methods will allow us to question the underlying processes precisely. This is a prospective, non-randomized, monocentric study with a sample of 24 breast cancer patients after treatment. The intervention is a 20 week programme (1 session per week) of aqua polo in a swim club facility, supervised by professional water-polo coaches. The variables measured are patient participation, quality of life (QLQ BR23), CRF (R-PFS) and post-traumatic growth (PTG-I) as well as different variables to observe physical capacity (strength with dynamometer, step-test and arm amplitude). The quality of the coach-patient relationship will be evaluated (CART-Q) to explore its dynamics. Participatory observations and interviews will be carried out to report on the interactions between the coach and the participants during the sessions.

Registration number and name of trial registry

No. EudraCT or ID-RCB: 2019-A03003-54 and NCT: NCT04235946.

Genetic variability of oxidative stress and DNA repair genes associated with pre-treatment cancer-related fatigue in women with breast cancer

PURPOSE

Investigate potential relationships between pre-treatment cancer-related fatigue (CRF) in women with early-stage breast cancer and variation in genes involved with oxidative stress and DNA repair.

METHODS

Investigated 39 functional and tagging single nucleotide polymorphisms (SNPs) in genes involved in oxidative stress (CAT, GPX1, SEPP1, SOD1, and SOD2) and DNA repair (ERCC2, ERCC3, ERCC5, and PARP1) in a sample (N = 219) that included n = 138 postmenopausal women diagnosed with early-stage breast cancer before initiation of therapy and n = 81 age- and education-matched healthy controls. Using the Profile of Mood States Fatigue/Inertia Subscale, fatigue occurrence and severity were evaluated in both groups. Regression analysis was used to independently identify significant SNPs for three outcomes: 1) any fatigue versus no fatigue, 2) clinically meaningful versus non-clinically meaningful fatigue, and 3) fatigue severity. Using a weighted multi-SNP method, genetic risk scores (GRS) were calculated for each participant, and GRS models were constructed for each outcome. Models were adjusted for age, pain, and symptoms of depression and anxiety.

RESULTS

SEPP1rs3877899, ERCC2rs238406, ERCC2rs238416, ERCC2rs3916874, and ERCC3rs2134794 were associated with fatigue occurrence and had a significant GRS model (OR = 1.317, 95%CI [1.067, 1.675], P ≤ 0.05). One SNP, SOD2rs5746136, was significant for clinically meaningful fatigue; therefore, a GRS model could not be constructed. ERCC3rs4150407, ERCC3rs4150477, and ERCC3rs2134794 were associated with fatigue severity with a significant GRS model (b = 1.010, 95%CI [1.647, 4.577], R2 = 6.9%, P ≤ 0.01).

CONCLUSIONS

These results may contribute to identifying patients who are at risk of developing CRF. Oxidative stress and DNA repair biological pathways may be involved with CRF.

Study design and methods for the pilot study of muscadine grape extract supplement to improve fatigue among older adult cancer survivors (FOCUS) trial

INTRODUCTION

Fatigue is a prevalent symptom among both cancer survivors and older adults. Negative consequences of fatigue include increased sedentary behavior, decreased physical activity and function, and lower quality of life. Few pharmacologic interventions improve fatigue. Our preclinical and clinical data show promising effects of a muscadine grape extract supplement (MGES) on oxidative stress, mitochondrial bioenergetics, the microbiome, and the symptom of fatigue. This pilot study seeks to translate these observations to cancer survivorship by testing the preliminary effect of MGE supplementation on older adult cancer survivors with self-reported fatigue.

MATERIALS AND METHODS

We designed a double-blinded placebo-controlled pilot study to evaluate preliminary efficacy of MGE supplementation versus placebo on fatigue among older adult cancer survivors (aged ≥65 years) who report baseline fatigue. Sixty-four participants will be enrolled and randomized 1:1 to twice daily MGES (four tablets twice daily) versus placebo for 12 weeks. The primary outcome is change in Patient-Reported Outcomes Measurement Information System (PROMIS) Fatigue score from baseline to 12 weeks. Secondary outcomes are change in self-reported physical function, physical fitness (6-min walk test), self-reported physical activity, global quality of life (QOL), and the Fried frailty index. Correlative biomarker assays will assess changes in 8-hydroxy-2 deoxyguanosine, peripheral blood mitochondrial function, inflammatory markers, and the gut microbiome.

DISCUSSION

This pilot study builds on preclinical and clinical observations to estimate effects of MGE supplementation on fatigue, physical function, QOL, and biologic correlates in older adult cancer survivors. Trial registration #: CT.govNCT04495751; IND 152908.

Cancer-related Fatigue in Lung Cancer: A Research Agenda: An Official American Thoracic Society Research Statement

Background: Fatigue is the most common symptom among cancer survivors. Cancer-related fatigue (CRF) may occur at any point in the cancer care continuum. Multiple factors contribute to CRF development and severity, including cancer type, treatments, presence of other symptoms, comorbidities, and medication side effects. Clinically, increasing physical activity, enhancing sleep quality, and recognizing sleep disorders are integral to managing CRF. Unfortunately, CRF is infrequently recognized, evaluated, or treated in lung cancer survivors despite more frequent and severe symptoms than in other cancers. Therefore, increased awareness and understanding of CRF are needed to improve health-related quality of life in lung cancer survivors. Objectives: 1) To identify and prioritize knowledge and research gaps and 2) to develop and prioritize research questions to evaluate mechanistic, diagnostic, and therapeutic approaches to CRF among lung cancer survivors. Methods: We convened a multidisciplinary panel to review the available literature on CRF, focusing on the impacts of physical activity, rehabilitation, and sleep disturbances in lung cancer. We used a three-round modified Delphi process to prioritize research questions. Results: This statement identifies knowledge gaps in the 1) detection and diagnostic evaluation of CRF in lung cancer survivors; 2) timing, goals, and implementation of physical activity and rehabilitation; and 3) evaluation and treatment of sleep disturbances and disorders to reduce CRF. Finally, we present the panel's initial 32 research questions and seven final prioritized questions. Conclusions: This statement offers a prioritized research agenda to 1) advance clinical and research efforts and 2) increase awareness of CRF in lung cancer survivors.

Treatment of Cancer-related-Fatigue in Acute Hematological Malignancies: Results of a Feasibility Study of using Cognitive Behavioral Therapy

BACKGROUND

Despite cancer related fatigue (CRF) being the most common, and debilitating symptom in patients with recently diagnosed acute hematological malignancies (HM), there are limited effective treatments for CRF in HM. The aim of this study was to determine the feasibility of cognitive behavioral therapy (CBT) for CRF in HM.

METHODS

In this preliminary longitudinal prospective study, HM patients diagnosed a median of one month previously with moderate to severe fatigue were enrolled. Patients received CBT in seven weekly sessions for eight weeks. Change in Functional Assessment of Cancer Illness Therapy (FACIT) - Fatigue (primary), FACT-G, Pittsburg Sleep Quality Index (PSQI), Hospital Anxiety Depression Scale (HADS), M.D. Anderson Symptom Inventory - Acute Myeloid Leukemia (MDASI-AML/MDS), and Herth Hope Index (HHI) were analyzed.

RESULTS

Twenty-seven of 36 (75 %) patients were evaluable. Adherence and satisfaction rates to the CBT intervention were 78.6% (95% CI 67.2%, 89.9%), and 92% (95% CI 76.7%, 98.3%) respectively. The median age 66, 64% female, the most common HM was AML (60%), median FACIT-F was 27. The mean (SD) improvement at end eight weeks for FACIT-F was 5.5(13.6), Cohen δ 0.4, P=0.046; and for PSQI total was 2.9 (3), Cohen δ -1, P=0.006. We also found significant improvement in HADS anxiety -2.7(4.5), P=0.049, MDASI Sleep -1.8(3.0), P=0.022, MDASI mean module symptom severity -0.7(1.6), P=0.006. However, no significant improvements were found in FACT-G, HHI, and HADS-depression scores.

CONCLUSIONS

The use of CBT was feasible with improvement of CRF, sleep quality, and anxiety scores in HM. Randomized controlled trials are justified.

[Special Consultation Hour for Patients with Cancer-Related Fatigue: Study Protocol of an Observational Study of a Nationwide Health Care Structure by the Bavarian Cancer Society (BKG) in Bavaria]

Cancer-related fatigue (CRF) is a burdensome condition of persistent tiredness, weakness, and lack of energy on physical, emotional, and cognitive level. CRF occurs in the context of cancer and/or its therapy and correlates with limitations in everyday life functioning, quality of life, and survival time. Up to now, medical care in Germany is inadequate. German wide institutions are lacking, which are specialised in identifying treatable factors influencing CRF as well as in counselling of adequate, evidence-based treatments. Since 2013, the Bavarian Cancer Society (BCS) implemented a nationwide health care structure with ten psychosocial cancer counselling centers in Bavaria. At these locations, the BCS offers for cancer patients with CRF special consultation hours with well-founded diagnostic and guidance. During the conception and further development of the consultation hour, all relevant guidelines have been considered. All consultation hours are directed by physicians with oncological and psycho-oncological experience. All of them took part in an extensive CRF training. The aim of this prospective, multicentre, observational study is the evaluation of the actual state of the TF-consultation including the analyses of offer and need for TF-consultation hours, of patient-reported TF before TF-consultation and ten weeks later, of realization of the recommended interventions to reduce TF as well as the analysis of strengths and potentials for improvement of the current system. The results will help to implement a German wide care structure.

Longitudinal associations of plasma metabolites with persistent fatigue among colorectal cancer survivors up to 2 years after treatment

The underlying biological mechanisms causing persistent fatigue complaints after colorectal cancer treatment need further investigation. We investigated longitudinal associations of circulating concentrations of 138 metabolites with total fatigue and subdomains of fatigue between 6 weeks and 2 years after colorectal cancer treatment. Among stage I-III colorectal cancer survivors (n = 252), blood samples were obtained at 6 weeks, and 6, 12 and 24 months posttreatment. Total fatigue and fatigue subdomains were measured using a validated questionnaire. Tandem mass spectrometry was applied to measure metabolite concentrations (BIOCRATES AbsoluteIDQp180 kit). Confounder-adjusted longitudinal associations were analyzed using linear mixed models, with false discovery rate (FDR) correction. We assessed interindividual (between-participant differences) and intraindividual longitudinal associations (within-participant changes over time). In the overall longitudinal analysis, statistically significant associations were observed for 12, 32, 17 and three metabolites with total fatigue and the subscales "fatigue severity," "reduced motivation" and "reduced activity," respectively. Specifically, higher concentrations of several amino acids, lysophosphatidylcholines, diacylphosphatidylcholines, acyl-alkylphosphatidylcholines and sphingomyelins were associated with less fatigue, while higher concentrations of acylcarnitines were associated with more fatigue. For "fatigue severity," associations appeared mainly driven by intraindividual associations, while for "reduced motivation" stronger interindividual associations were found. We observed longitudinal associations of several metabolites with total fatigue and fatigue subscales, and that intraindividual changes in metabolites over time were associated with fatigue severity. These findings point toward inflammation and an impaired energy metabolism due to mitochondrial dysfunction as underlying mechanisms. Mechanistic studies are necessary to determine whether these metabolites could be targets for intervention.

Moxibustion for the Treatment of Cancer and its Complications: Efficacies and Mechanisms

Cancer treatment remains a significant challenge for the medical community, and improved therapies are necessary to treat cancer and its associated complications. Current anticancer therapies often have significant side effects, underscoring the need for new treatment options. Moxibustion is a representative external therapy used in traditional Chinese medicine. This review examines clinical studies demonstrating moxibustion's ability to improve the efficacy of radiotherapy and chemotherapy and control tumor progression. Moxibustion can prevent and treat various complications of cancer, including cancer-related or therapy-induced gastrointestinal symptoms, myelosuppression, fatigue, pain, and postoperative lymphedema. has also been shown to enhance the quality of life for cancer patients. However, very few studies have investigated the underlying mechanisms for these effects, a topic that requires systematic elucidation. Evidence has shown that moxibustion alone or combined with chemotherapy can improve survival and inhibit tumor growth in cancer-bearing animal models. The anticancer effect of moxibustion is associated with alleviating the tumor immunosuppressive and vascular microenvironments. Additionally, the therapeutic effects of moxibustion may originate from the heat and radiation produced during the combustion process on acupoints or lesions. This evidence provides a scientific basis for the clinical application of moxibustion in anticancer treatment and reducing the side effects of cancer therapies and helps promote the precise application of moxibustion in cancer treatment.

Obesity reduced survival with 5-fluorouracil and did not protect against chemotherapy-induced cachexia or immune cell cytotoxicity in mice

Fluorouracil/5-flourouracil (5FU) is a first-line chemotherapy drug for many cancer types; however, its associated toxicities contribute to poor quality of life and reduced dose intensities negatively impacting patient prognosis. While obesity remains a critical risk factor for most cancers, our understanding regarding how obesity may impact chemotherapy's toxicities is extremely limited. C56BL/6 mice were given high fat (Obese) or standard diets (Lean) for 4 months and then subjected to three cycles of 5FU (5d-40 mg/kg Lean Mass, 9d rest) or PBS vehicle control. Shockingly, only 60% of Obese survived 3 cycles compared to 100% of Lean, and Obese lost significantly more body weight. Dihydropyrimidine dehydrogenase (DPD), the enzyme responsible for 5FU catabolism, was reduced in obese livers. Total white blood cells, neutrophils, and lymphocytes were reduced in Obese 5FU compared to Lean 5FU and PBS controls. While adipocyte size was not affected by 5FU in Obese, skeletal muscle mass and myofibrillar cross section area were decreased following 5FU in Lean and Obese. Although adipose tissue inflammatory gene expression was not impacted by 5FU, distinct perturbations to skeletal muscle inflammatory gene expression and immune cell populations (CD45+ Immune cells, CD45+CD11b+CD68+ macrophages and CD45+CD11b+Ly6clo/int macrophage/monocytes) were observed in Obese only. Our evidence suggests that obesity induced liver pathologies and reduced DPD exacerbated 5FU toxicities. While obesity has been suggested to protect against cancer/chemotherapy-induced cachexia and other toxicities, our results demonstrate that obese mice are not protected, but rather show evidence of increased susceptibility to 5FU-induced cytotoxicity even when dosed for relative lean mass.

Meta-Analysis of Pharmacological, Nutraceutical and Phytopharmaceutical Interventions for the Treatment of Cancer Related Fatigue

Purpose: In this study we aimed to estimate the effectiveness of pharmacological, nutraceutical, and phytopharmaceutical treatments on CRF. Methods: Ovid MEDLINE, Ovid Embase, Ovid Psych info, CINHAHL and Cochrane Library databases were searched up to 30 September 2021. Randomized controlled trials of pharmacological, nutraceutical and phytopharmaceutical interventions for treatment of CRF for at least one week duration and have used valid tool to assess severity of CRF as a primary or secondary outcome were considered. Results: 32 eligible studies (4896 patients) were reviewed. For the overall meta-analysis, the random effect models yielded the treatment effect (95% CI) of −0.29 (−0.48,−0.09), p < 0.001. The meta-analysis did not show significant reduction of CRF with treatment with ginseng (n = 6), guarana (n = 3), megestrol (n = 2), mistletoe (n = 3), psychostimulants (n = 14), SSRI/antidepressants (n = 2). Corticosteroids (n = 2) showed significant reduction in CRF with treatment effects of 0.94 (−1.21, −0.67), p <0.0001, respectively. Conclusions: In this study, overall meta-analysis of all studies demonstrates significant reduction of CRF using Pharmacological, Nutraceutical and Phytopharmaceutical interventions with a pooled standardized treatment effect of −0.29. Metanalysis of Corticosteroids studies showed significant reduction in CRF. Further studies are needed.

Effects of exercise on inflammatory factors and IGF system in breast cancer survivors: a meta-analysis

BACKGROUND

At present, there are multiple hypotheses regarding the mechanisms underlying the effect of exercise on the postoperative inflammatory factors and the IGF system among breast cancer patients, especially. To determine the underlying mechanisms, prevent the recurrence of breast cancer and improve its prognosis, this paper will systematically evaluate the impact of exercise on inflammatory factors and the IGF system in breast cancer survivors.

METHODS

The PubMed, Embase, Web of Science, CNKI, Wanfang and VIP (Chinese scientific and technical journals) databases were systematically searched until April 2021. The search terms included 'exercise', 'inflammatory factor', 'IGF system' and 'breast cancer'. A total of 1066 relevant articles were retrieved. The articles were screened according to inclusion and exclusion criteria, such as study population, intervention method and type of experiment, and 11 articles were ultimately included. All statistical results were analysed using STATA 14.0 and Rstudio 4.1.1.

RESULTS

We found that exercise significantly reduced the level of IGF-1 (WMD, -19.947 ng/ml; 95% CI, -22.669 to -17.225; P = 0.000). Subgroup analysis showed that in the studies with an intervention period > 12 weeks, exercise significantly reduced IL-6 levels (WMD, -0.761 pg/ml; 95% CI, -1.369 to -0.153; p = 0.014), while in the studies with an intervention period ≤ 12 weeks, exercise significantly reduced CRP (WMD, -2.381 mg/L; 95% CI, -4.835 to 0.073, P = 0.001) and IL-10 levels (WMD, -7.141 pg/ml, 95% CI, -10.853 to -3.428; P = 0.000). In addition, aerobic exercise plus resistance training significantly reduced IL-6 levels (WMD, -1.474 pg/ml; 95% CI, -1.653 to -1.296; P = 0.000). The results of the sensitivity analysis showed that after excluding the studies with high heterogeneity, exercise significantly reduced the TNF-α levels in patients with breast cancer (WMD, -1.399 pg/ml; 95% CI, -1.718 to -1.080; P = 0.000).

CONCLUSION

Exercise reduces the postoperative levels of IGF-1, IL-6, CRP, IL-10 and TNF-α among patients with breast cancer, which may have a significant impact on inhibiting breast cancer recurrence and improving its prognosis. Future studies should examine the effects of different durations and types of exercise to develop individualized exercise prescriptions for breast cancer patients.

Circulating levels of IL-6 and TGF-β1 in patients with prostate cancer undergoing radiotherapy: associations with acute radiotoxicity and fatigue symptoms

Background

The goal of research was to investigate the possible relations between serum concentrations of IL-6 and TGF-β1, individual and clinical characteristics, and adverse effects of radiotherapy in patients with prostate cancer: acute and late genitourinary and gastrointestinal toxicity, and fatigue.

Methods

Thirty-nine patients with localized or locally advanced prostate cancer who were treated with radiotherapy were enrolled in this study. The acute radiotoxicity grades and fatigue levels were assessed during the radiotherapy and 1 month after the radiotherapy. Estimation of the late radiotoxicity was performed every three months in the first year, every four months in the second year, and then every six months. Serum levels of IL-6 and TGF-β1 were determined before radiotherapy and after the 25th radiotherapy fraction by ELISA.

Results

The significant positive association between diabetes mellitus and changes in acute genitourinary toxicity grades during the radiotherapy was observed in prostate cancer patients. In addition, patients who were smokers had significantly higher maximum fatigue levels in comparison with patients who were non-smokers. The circulating IL-6 levels were significantly higher after the 25th radiotherapy fraction in comparison with levels determined before radiotherapy. The significant positive correlations between pretreatment TGF-β1 levels and maximum genitourinary toxicity grades and between TGF-β1 levels after the 25th fraction and genitourinary toxicity grades after the 25th fraction, were found. The pretreatment IL-6 concentrations and TGF-β1 concentrations after the 25th fraction were positively correlated with maximum genitourinary toxicity grades. The IL-6 levels after the 25th fraction were positively associated with genitourinary toxicity grades after this fraction. The pretreatment IL-6 concentrations were significantly positively correlated with maximum fatigue scores. The significant positive correlation between IL-6 concentrations and fatigue scores after the 25th fraction was determined. The positive correlations between IL-6 and TGF-β1 concentrations measured after the 25th fraction and maximum fatigue scores were observed.

Conclusions

Our results suggest that serum levels of IL-6 and TGF-β1 might influence the severity of acute genitourinary radiotoxicity and fatigue in patients with prostate cancer. Combining clinical parameters and circulating cytokine levels might be useful for the prediction of adverse reactions to radiotherapy.

Inflammatory, Oxidative Stress, and Cardiac Damage Biomarkers and Radiation-Induced Fatigue in Breast Cancer Survivors

PURPOSE

Studies examining biomarkers associated with fatigue in breast cancer survivors treated with radiation are limited. Therefore, we examined the longitudinal association between serum biomarkers and post-breast cancer fatigue in survivors treated with radiation: [oxidative stress] 8-hydroxyguanosine, myeloperoxidase; [inflammation] interleukin-6 (IL-6), c-reactive protein, growth differentiation factor-15 (GDF-15), placental growth factor, transforming growth factor-beta, [cardiac damage] cystatin-C, troponin-I.

METHODS

In a secondary analysis, we included participants from the Women's Health Initiative if they had: a previous breast cancer diagnosis (stages I-III), no prior cardiovascular diseases, pre-and post-breast cancer serum samples drawn approximately 3 years apart, and fatigue measured using the Short-Form 36 vitality subscale at both serum collections. Biomarkers were measured using ELISA or RT-qPCR and modeled as the log2 post-to pre-breast cancer ratio.

RESULTS

Overall, 180 women with a mean (SD) age of 67.0 (5.5) years were included. The mean (SD) vitality scores were 66.2 (17.2) and 59.7 (19.7) pre- and post-breast cancer, respectively. Using multivariable weighted linear regression, higher biomarker ratios of cystatin-C, IL-6, and GDF-15 were associated with a lower vitality score (i.e., higher fatigue). For example, for each 2-fold difference in cystatin-C biomarker ratio, the vitality score was lower by 7.31 points (95% CI: -14.2, -0.45).

CONCLUSION

Inflammatory and cardiac damage biomarkers are associated with fatigue in breast cancer survivors treated with radiation; however, these findings should be replicated in a larger sample. Biomarkers could be measured in clinical practice or assessed in risk prediction models to help identify patients at high risk for fatigue.

Acupuncture for Managing Cancer-Related Fatigue in Breast Cancer Patients: A Systematic Review and Meta-Analysis

Breast cancer (BC) is the most common cancer in women and is a serious threat to women's health. Cancer-related fatigue (CRF) is a distressing symptom in BC patients during and after chemotherapy or radiation therapy that severely affects quality of life (QoL). AT is widely used for fatigue management. However, the effect of AT on CRF is still uncertain. This study aimed to evaluate the efficacy and safety of AT in the management of CRF in patients with BC. Eleven databases were searched through June 2022. Two researchers independently performed the database search, study selection, data extraction, and risk of bias assessment. Study selection was performed based on predefined Participants, Intervention, Comparators, Outcomes, Study design (PICOS) criteria, and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed when reporting the results. A meta-analysis was performed according to the Cochrane systematic review method using RevMan 5.3. A total of 12 studies including a total of 1084 participants were included. The results showed that AT had a beneficial effect compared with sham AT (n = 256, SMD = -0.26, 95% CI [-0.51, -0.01], p = 0.04, I² = 0%) and a long-term effect on fatigue score (n = 209, MD = -0.32, 95% CI [-0.59, -0.04], p = 0.02, I² = 0%). Meta-analysis showed that AT had a beneficial effect compared with usual care (UC) on fatigue scores (n = 238, SMD = -0.39, 95% CI [-0.66 to -0.12], p = 0.005, I² = 0%). Of the 12 articles, 3 articles were judged as having a low risk of bias in all domains and hence were of high quality. No serious adverse effects were identified. AT is an effective and safe treatment for CRF, and AT is more effective than sham AT or UC or wait-list control (WLC). Nevertheless, the methodological quality of most of these studies was low, and the included studies/sample sizes were small, so the ability to derive decisive implications was limited. Further research is needed to confirm these findings.

The association between cancer-related fatigue and diabetes from pre-chemotherapy to 6 months post-chemotherapy

PURPOSE

To quantify the relationship between diabetes and fatigue from pre-chemotherapy to 6 months post-chemotherapy for women with breast cancer compared to women without a history of cancer (controls).

METHODS

This was a secondary analysis from a nationwide prospective longitudinal study of female patients with breast cancer undergoing chemotherapy and controls. Diabetes diagnosis (yes/no) was obtained at baseline, and cancer-related fatigue was measured using the Multidimensional Fatigue Symptom Inventory (MFSI) pre-, post-, and 6 months post-chemotherapy in patients; controls were assessed at equivalent time points. Repeated measures mixed effects models estimated the association between fatigue and diabetes controlling for cancer (yes/no), body mass index, exercise and smoking habits, baseline anxiety and depressive symptoms, menopausal status, marital status, race, and education.

RESULTS

Among 439 patients and 235 controls (52.8 ± 10.5 years old), diabetes was twice as prevalent among patients as controls (11.6% vs. 6.8%). At baseline, diabetes was associated with worse fatigue (4.1 ± 1.7 points, p = 0.017). Also, diabetes was associated with clinically meaningful worse fatigue throughout the study period among all participants (5.2 ± 1.9 points, p = 0.008) and patients alone (4.5 ± 2.0, p = 0.023). For the MFSI subdomains among patients, diabetes was associated with worse general (p = 0.005) and mental fatigue (p = 0.026).

CONCLUSIONS

Diabetes was twice as prevalent in women with breast cancer compared to controls, and diabetes was associated with more severe cancer-related fatigue in patients before and after chemotherapy and at 6 months post-chemotherapy. Interventions that address diabetes management may also help address cancer-related fatigue during chemotherapy treatment.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01382082, first posted June 27, 2011.

The Effects of a Mediterranean Diet Intervention on Cancer-Related Fatigue for Patients Undergoing Chemotherapy: A Pilot Randomized Controlled Trial

Cancer-related fatigue is a common, burdensome symptom of cancer and a side-effect of chemotherapy. While a Mediterranean Diet (MedDiet) promotes energy metabolism and overall health, its effects on cancer-related fatigue remain unknown. In a randomized controlled trial, we evaluated a rigorous MedDiet intervention for feasibility and safety as well as preliminary effects on cancer-related fatigue and metabolism compared to usual care. Participants had stage I−III cancer and at least six weeks of chemotherapy scheduled. After baseline assessments, randomization occurred 2:1, MedDiet:usual care. Measures were collected at baseline, week 4, and week 8 including MedDiet adherence (score 0−14), dietary intake, and blood-based metabolic measures. Mitochondrial respiration from freshly isolated T cells was measured at baseline and four weeks. Participants (n = 33) were 51.0 ± 14.6 years old, 94% were female, and 91% were being treated for breast cancer. The study was feasible, with 100% completing the study and >70% increasing their MedDiet adherence at four and eight weeks compared to baseline. Overall, the MedDiet intervention vs. usual care had a small-moderate effect on change in fatigue at weeks 4 and 8 (ES = 0.31, 0.25, respectively). For those with a baseline MedDiet score <5 (n = 21), the MedDiet intervention had a moderate-large effect of 0.67 and 0.48 at weeks 4 and 8, respectively. The MedDiet did not affect blood-based lipids, though it had a beneficial effect on fructosamine (ES = −0.55). Fatigue was associated with mitochondrial dysfunction including lower basal respiration, maximal respiration, and spare capacity (p < 0.05 for FACIT-F fatigue subscale and BFI, usual fatigue). In conclusion, the MedDiet was feasible and attenuated cancer-related fatigue among patients undergoing chemotherapy, especially those with lower MedDiet scores at baseline.

Mechanisms of Neuromuscular Fatigability in People with Cancer-Related Fatigue

INTRODUCTION

Cancer-related fatigue (CRF) is a debilitating symptom that affects around one-third of people for months or years after cancer treatment. In a recent study, we found that people with posttreatment CRF have greater neuromuscular fatigability. The aim of this secondary analysis was to examine the etiology of neuromuscular fatigability in people with posttreatment CRF.

METHODS

Ninety-six people who had completed cancer treatment were dichotomized into two groups (fatigued and nonfatigued) based on a clinical cut point for fatigue. Alterations in neuromuscular function (maximal voluntary contraction peak force, voluntary activation, potentiated twitch force, and EMG) in the knee extensors were assessed across three common stages of an incremental cycling test. Power outputs during the fatigability test were expressed relative to gas exchange thresholds to assess relative exercise intensity.

RESULTS

The fatigued group had a more pronounced reduction in maximal voluntary contraction peak force and potentiated twitch force throughout the common stages of the incremental cycling test (main effect of group: P < 0.001, ηp2 = 0.18 and P = 0.029, ηp2 = 0.06, respectively). EMG was higher during cycling in the fatigued group (main effect of group: P = 0.022, ηp2 = 0.07). Although the relative intensity of cycling was higher in the fatigued group at the final common stage of cycling, this was not the case during the initial two stages, despite the greater impairments in neuromuscular function.

CONCLUSIONS

Our results suggest that the rapid impairments in neuromuscular fatigability in people with CRF were primarily due to disturbances at the level of the muscle rather than the central nervous system. This could affect the ability to tolerate daily physical activities.

Exercise Interventions to Combat Cancer-Related Fatigue in Cancer Patients Undergoing Treatment: A Review

There was an average of 45,753 cancer diagnoses each year in Ireland from 2018-2020. Estimates state that by the year 2045, this average could increase by 50-100%. There are over 170,000 cancer survivors living in Ireland. Cancer-related fatigue (CRF) is a prevalent and debilitating side effect of cancer and cancer treatment. Research has demonstrated that exercise is an effective intervention to combat CRF. This review will examine the scope of CRF and critically analyse exercise interventions to combat CRF in cancer patients undergoing treatment.Aerobic exercise interventions and multimodal exercise (aerobic exercise, resistance exercise and flexibility exercise) interventions have been shown to improve symptoms of fatigue in cancer patients undergoing treatment. The effect of resistance training on CRF in cancer patients during treatment is not well understood. Aerobic exercise and multimodal exercise appear to combat CRF by improving one or more of the following health-related fitness parameters; aerobic capacity, muscular strength and endurance, flexibility, and body composition.A standardised process of recording the intensity and volume of aerobic, resistance and flexibility exercise should be developed. Future studies should investigate in greater detail the role of resistance training in reducing CRF among cancer patients. Qualitative methods should be developed to investigate the role the group dynamic has on cancer patients during group based interventions. These qualitative methods may be able to determine the importance the delivery of exercise plays in reducing CRF. Biomarkers of CRF should be investigated and examined in relation to the specific dose of exercise that patients perform.

Time-restricted Eating to Address Cancer-related Fatigue among Cancer Survivors: A Single-arm Pilot Study

Purpose

Cancer-related fatigue is a prevalent, debilitating condition that can persist for months or years after treatment. In a single-arm clinical trial, the feasibility and safety of a time-restricted eating (TRE) intervention were evaluated among cancer survivors, and initial estimates of within-person change in cancer-related fatigue were obtained.

Methods

Participants were 4-60 months post-cancer treatment, were experiencing fatigue (≥ 3 on a scale 0-10), and were not following TRE. TRE entailed limiting all food and beverages to a self-selected 10-h window for 14 days. Participants reported their eating window in a daily diary and completed the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F), Brief Fatigue Inventory (BFI), and symptom inventory pre- and post-intervention. This study was pre-registered at clinicaltrials.gov in January 2020 (NCT04243512).

Results

Participants (n=39) were 61.5 ± 12.4 years old and 1.8 ± 1.3 years post-treatment; 89.7% had had breast cancer. The intervention was feasible in that 36/39 (92.3%) of participants completed all questionnaires and daily diaries. It was also safe with no severe adverse events or rapid weight loss (average loss of 1.1 ± 2.3 pounds, p=0.008). Most adhered to TRE; 86.1% ate within a 10-h window at least 80% of the days, and the average eating window was 9.33 ± 1.05 h. Fatigue scores improved 5.3 ± 8.1 points on the FACIT-F fatigue subscale (p<0.001, effect size [ES]=0.55), 30.6 ± 35.9 points for the FACIT-F total score (p<0.001, ES=0.50), and -1.0 ± 1.7 points on the BFI (p<0.001, ES=-0.58).

Conclusion

A 10-h TRE intervention was feasible and safe among survivors, and fatigue improved with a moderate effect size after two weeks.

Limitations

This was a single-arm study, so it is possible that expectation effects were present for fatigue outcomes, independent of effects of TRE per se. However, this feasibility trial supports evaluation of TRE in randomized controlled trials to address persistent cancer-related fatigue.

The Clinical Observation and Mechanism of Acupuncture on Cancer-Related Fatigue of Breast Cancer Based on “Gut-Brain Axis”: Study Protocol for a Randomized Controlled Trial

Background. Cancer-related fatigue (CRF) is a painful, persistent feeling of physical and cognitive subjective fatigue related to cancer or cancer remedy. The occurrence of CRF may be related to the hypothalamic-pituitary-adrenaline (HPA) axis, inflammatory mediator theory, and gut microbiota. Moreover, acupuncture could play a vital part in the therapy of CRF. The study will evaluate whether acupuncture can improve fatigue symptoms of CRF patients after breast cancer chemotherapy by regulating the gut-brain axis. Methods/design. Seventy patients with CRF will be enrolled in this study, with 35 patients randomly assigned to each group. Blood and feces will be collected at the beginning and end of treatment. Piper fatigue scale, KPS score scale, and quality-of-life scale will be used to observe the changes of fatigue symptoms and life quality of CRF patients and to evaluate the effect of acupuncture on CRF. Then, the method of ELISA will be used to explore the regulatory effect of acupuncture on the HPA axis and inflammatory cytokines. Moreover, based on 16SrDNA, the changes of gut microbiota structure and flora of CRF patients will be observed. Ultimately, the correlation analysis of gut microbiota can be related to inflammatory cytokines, HPA axis, and clinical efficacy evaluation. Discussion. This study will identify the effect and the mechanism of acupuncture therapy in CRF. And it will offer an alternative treatment modality for the treatment of CRF after chemotherapy for breast cancer. Furthermore, it will also provide the clinical and theoretical bases for the extensive application of acupuncture therapy in tumor rehabilitation. Trial Status. Protocol version number and date: V2.0, 6 May 2021. The trial is registered with the Chinese Clinical Trial Registry on 20 June 2021 (trial identifier: ChiCTR2100047510).

A New Approach to Understanding Cancer-Related Fatigue: Leveraging the 3P Model to Facilitate Risk Prediction and Clinical Care

Simple Summary

For the growing number of cancer survivors worldwide, fatigue presents a major hurdle to function and quality of life. Treatment options for cancer-related fatigue are still emerging, and our current understanding of its etiology is limited. In this paper, we describe a new application of a comprehensive model for cancer-related fatigue: the predisposing, precipitating, and perpetuating (3P) factors model. We propose that the 3P model may be leveraged—particularly using metabolomics, the microbiome, and inflammation in conjunction with behavioral science—to better understand the pathophysiology of cancer-related fatigue.

Abstract

A major gap impeding development of new treatments for cancer-related fatigue is an inadequate understanding of the complex biological, clinical, demographic, and lifestyle mechanisms underlying fatigue. In this paper, we describe a new application of a comprehensive model for cancer-related fatigue: the predisposing, precipitating, and perpetuating (3P) factors model. This model framework outlined herein, which incorporates the emerging field of metabolomics, may help to frame a more in-depth analysis of the etiology of cancer-related fatigue as well as a broader and more personalized set of approaches to the clinical treatment of fatigue in oncology care. Included within this review paper is an in-depth description of the proposed biological mechanisms of cancer-related fatigue, as well as a presentation of the 3P model’s application to this phenomenon. We conclude that a clinical focus on organization risk stratification and treatment around the 3P model may be warranted, and future research may benefit from expanding the 3P model to understand fatigue not only in oncology, but also across a variety of chronic conditions.

Exploratory Analysis of Associations Between Whole Blood Mitochondrial Gene Expression and Cancer-Related Fatigue Among Breast Cancer Survivors

BACKGROUND

Cancer-related fatigue is a prevalent, debilitating, and persistent condition. Mitochondrial dysfunction is a putative contributor to cancer-related fatigue, but relationships between mitochondrial function and cancer-related fatigue are not well understood.

OBJECTIVES

We investigated the relationships between mitochondrial DNA (mtDNA) gene expression and cancer-related fatigue, as well as the effects of fish and soybean oil supplementation on these relationships.

METHODS

A secondary analysis was performed on data from a randomized controlled trial of breast cancer survivors 4-36 months posttreatment with moderate-severe cancer-related fatigue. Participants were randomized to take 6 g fish oil, 6 g soybean oil, or 3 g each daily for 6 weeks. At pre- and postintervention, participants completed the Functional Assessment of Chronic Illness Therapy-Fatigue questionnaire and provided whole blood for assessment of mtDNA gene expression. The expression of 12 protein-encoding genes was reduced to a single dimension using principal component analysis for use in regression analysis. Relationships between mtDNA expression and cancer-related fatigue were assessed using linear regression.

RESULTS

Among 68 participants, cancer-related fatigue improved and expression of all mtDNA genes decreased over 6 weeks with no effect of treatment group on either outcome. Participants with lower baseline mtDNA gene expression had greater improvements in cancer-related fatigue. No significant associations were observed between mtDNA gene expression and cancer-related fatigue at baseline or changes in mtDNA gene expression and changes in cancer-related fatigue.

DISCUSSION

Data from this exploratory study add to the growing literature that mitochondrial dysfunction may contribute to the etiology and pathophysiology of cancer-related fatigue.

Serum carotenoids and cancer-related fatigue: An analysis of the 2005-2006 National Health and Nutrition Examination Survey

Cancer-related fatigue is a prevalent, debilitating condition, and preliminary evidence suggests a relationship between higher diet quality and lower fatigue. Serum-based carotenoids, Vitamin A, and Vitamin E are biomarkers of fruit and vegetable intake and therefore diet quality. To further elucidate the link between diet quality and cancer-related fatigue, associations were assessed between these serum-based nutrients and fatigue among American adults with special attention to cancer history. Data were analyzed from the United States 2005-2006 National Health and Nutrition Examination Survey (NHANES) dataset. Ten carotenoids, vitamin A, vitamin E, and γ-tocopherol were measured from fasting blood samples and fatigue was patient-reported. Associations between carotenoid concentration and fatigue were estimated using ordinal logistic regression models. Adjusted models included a diagnosis of cancer (with the exception on non-melanoma skin cancer, yes/no), age, body mass index, race/ethnicity, education, and exercise habits as covariates, and additional models included a cancer×nutrient interaction. Of 4091 participants, 272 (8.0%) reported a history of cancer. Greater fatigue was associated with lower serum trans-lycopene, retinyl palmitate, and retinyl stearate (all p<0.05) in separate models adjusting for potential confounders. For these nutrients, a one-standard deviation increase in nutrient was associated with a 6.8-9.9% lower risk of greater fatigue. Among cancer survivors only (n=272), statistically significant associations were not observed between any of the nutrients and fatigue. In conclusion, greater serum concentrations of carotenoid biomarkers were associated with less fatigue. These results support further exploration into relationships between carotenoid intake, diet quality, and persistent fatigue.