Fatigue in patients with chronic disease: results from the population-based Lifelines Cohort Study

Association of digital measures and self-reported fatigue: a remote observational study in healthy participants and participants with chronic inflammatory rheumatic disease

Background

Fatigue is a subjective, complex and multi-faceted phenomenon, commonly experienced as tiredness. However, pathological fatigue is a major debilitating symptom associated with overwhelming feelings of physical and mental exhaustion. It is a well-recognized manifestation in chronic inflammatory rheumatic diseases, such as Sjögren's Syndrome and Systemic Lupus Erythematosus and an important predictor of patient's health-related quality of life (HRQoL). Patient reported outcome questions are the key instruments to assess fatigue. To date, there is no consensus about reliable quantitative assessments of fatigue.

Method

Observational data for a period of one month were collected from 296 participants in the United States. Data comprised continuous multimodal digital data from Fitbit, including heart rate, physical activity and sleep features, and app-based daily and weekly questions covering various HRQoL factors including pain, mood, general physical activity and fatigue. Descriptive statistics and hierarchical clustering of digital data were used to describe behavioural phenotypes. Gradient boosting classifiers were trained to classify participant-reported weekly fatigue and daily tiredness from multi-sensor and other participant-reported data, and extract a set of key predictive features.

Results

Cluster analysis of Fitbit parameters highlighted multiple digital phenotypes, including sleep-affected, fatigued and healthy phenotypes. Features from participant-reported data and Fitbit data both contributed as key predictive features of weekly physical and mental fatigue and daily tiredness. Participant answers to pain and depressed mood-related daily questions contributed the most as top features for predicting physical and mental fatigue, respectively. To classify daily tiredness, participant answers to questions on pain, mood and ability to perform daily activities contributed the most. Features related to daily resting heart rate and step counts and bouts were overall the most important Fitbit features for the classification models.

Conclusion

These results demonstrate that multimodal digital data can be used to quantitatively and more frequently augment pathological and non-pathological participant-reported fatigue.

Effects of acceptance and commitment therapy on fatigue for patients with cancer and other chronic health conditions: A systematic review and meta-analysis

OBJECTIVE

Fatigue is significantly more prevalent in the chronically ill compared to healthy individuals. Fatigue is one of the most reported and debilitating symptoms in individuals with chronic health conditions. Despite this, there is limited evidence examining the efficacy of psychological interventions to reduce fatigue, with the majority having focused on Cognitive Behaviour Therapy. As Acceptance and Commitment Therapy (ACT) has shown to be efficacious in improving other outcomes for people with chronic health conditions, this systematic review and meta-analysis aimed to determine the efficacy of ACT in reducing fatigue for this population.

METHODS

A systematic search in MEDLINE, EMBASE, CINAHL, PsycINFO, Cochrane Library, US National Library of Medicine Clinical Trial Register and reference lists of relevant papers was conducted to obtain relevant studies. Inclusion criteria specified the study needed to be a randomised controlled trial which implemented an ACT predominant intervention and measured fatigue in adults with a chronic health condition. Data was pooled using the inverse-variance random effects model, with restricted maximum likelihood estimation, providing the standardized mean difference between control and experimental groups post intervention.

RESULTS

The current systematic review and meta-analysis included eight RCTs. Participants with a chronic condition (including cancer and fibromyalgia) who received ACT interventions, displayed reduced levels of fatigue, indicative of a small effect (SMD = -0.16, 95% CI [-0.30, -0.01], p = 0.03).

CONCLUSION

While the evidence is limited to cancer and fibromyalgia, ACT shows promise in reducing fatigue. Future research should examine ACT for fatigue in other chronic health condition populations to broaden the scope of these findings.

The relation between cognitive-behavioural responses to symptoms in patients with long term medical conditions and the outcome of cognitive behavioural therapy for fatigue - A secondary analysis of four RCTs

BACKGROUND

Cognitive behavioural therapy (CBT) is effective in reducing fatigue across long-term conditions (LTCs). This study evaluated whether cognitive and behavioural responses to symptoms: 1) differ between LTCs and 2) moderate and/or mediate the effect of CBT on fatigue.

METHOD

Data were used from four Randomized Controlled Trials testing the efficacy of CBT for fatigue in Chronic Fatigue Syndrome/ME (N = 240), Multiple Sclerosis (N = 90), Type 1 Diabetes Mellitus (N = 120) and Q-fever fatigue syndrome (N = 155). Fatigue severity, assessed with the Checklist Individual Strength, was the primary outcome. Differences in fatigue perpetuating factors, assessed with the Cognitive Behavioural Responses to Symptoms Questionnaire (CBRQ), between diagnostic groups were tested using ANCOVAs. Linear regression and mediation analyses were used to investigate moderation and mediation by CBRQ scores of the treatment effect.

RESULTS

There were small to moderate differences in CBRQ scores between LTCs. Patients with higher scores on the subscales damage beliefs and avoidance/resting behaviour at baseline showed less improvement following CBT, irrespective of diagnosis. Reduction in fear avoidance, catastrophising and avoidance/resting behaviour mediated the positive effect of CBT on fatigue across diagnostic groups.

DISCUSSION

The same cognitive-behavioural responses to fatigue moderate and mediate treatment outcome across conditions, supporting a transdiagnostic approach to fatigue.

Subjective sleep quality and fatigue assessment in Polish adult patients with primary immunodeficiencies: A pilot study

Introduction

Primary immunodeficiencies (PIDs) are clinically heterogeneous disorders caused by abnormalities in the immune system. However, PIDs are genetically determined and may occur at any age from early childhood to elderly age. Due to chronic patterns, the risk of malignancy and organ damage in patients with PIDs may affect any aspect of life, including sleep patterns. To our knowledge, the prevalence of insomnia and subjective sleep quality have not been investigated in patients with PIDs. Therefore, this pilot study was conducted to investigate sleep quality, the prevalence of sleep disturbances, and fatigue in adult patients with PIDs in Poland.

Methods

All participants were surveyed using the Athens Insomnia Scale, Pittsburgh Sleep Quality Index, Fatigue Severity Scale, and a questionnaire concerning general health and demographic data. We included 92 participants: 48 women (52.2%) and 44 men (47.8%).

Results

Participants' mean age was 41.9 ± 13.9 years. The mean sleep duration was 7.0 ± 1.5 hours, and the mean sleep latency was 41.2 ± 53.1 minutes. Additionally, 44.6% of patients (n=41) had symptoms of insomnia and 44.6% (n=42) had poor sleep quality. Less than one-fourth (n=22; 23.9%) of the patients reported the use of sleeping pills; moreover, clinically significant fatigue was reported in 52.2% (n=48).

Discussion

Our investigation provides insight into the problem of sleep disturbances in patients with PIDs. Data have demonstrated that sleeping disorders with concomitant fatigue are common in patients with PID. Further studies are needed to determine the determinants of poor sleep quality in this specific group of patients.

Non-invasive brain stimulation for fatigue in post-acute sequelae of SARS-CoV-2 (PASC)

BACKGROUND

and purpose: Fatigue is among the most common persistent symptoms following post-acute sequelae of Sars-COV-2 infection (PASC). The current study investigated the potential therapeutic effects of High-Definition transcranial Direct Current Stimulation (HD-tDCS) associated with rehabilitation program for the management of PASC-related fatigue.

METHODS

Seventy patients with PASC-related fatigue were randomized to receive 3 mA or sham HD-tDCS targeting the left primary motor cortex (M1) for 30 min paired with a rehabilitation program. Each patient underwent 10 sessions (2 sessions/week) over five weeks. Fatigue was measured as the primary outcome before and after the intervention using the Modified Fatigue Impact Scale (MFIS). Pain level, anxiety severity and quality of life were secondary outcomes assessed, respectively, through the McGill Questionnaire, Hamilton Anxiety Rating Scale (HAM-A) and WHOQOL.

RESULTS

Active HD-tDCS resulted in significantly greater reduction in fatigue compared to sham HD-tDCS (mean group MFIS reduction of 22.11 points vs 10.34 points). Distinct effects of HD-tDCS were observed in fatigue domains with greater effect on cognitive (mean group difference 8.29 points; effect size 1.1; 95% CI 3.56-13.01; P < .0001) and psychosocial domains (mean group difference 2.37 points; effect size 1.2; 95% CI 1.34-3.40; P < .0001), with no significant difference between the groups in the physical subscale (mean group difference 0.71 points; effect size 0.1; 95% CI 4.47-5.90; P = .09). Compared to sham, the active HD-tDCS group also had a significant reduction in anxiety (mean group difference 4.88; effect size 0.9; 95% CI 1.93-7.84; P < .0001) and improvement in quality of life (mean group difference 14.80; effect size 0.7; 95% CI 7.87-21.73; P < .0001). There was no significant difference in pain (mean group difference -0.74; no effect size; 95% CI 3.66-5.14; P = .09).

CONCLUSION

An intervention with M1 targeted HD-tDCS paired with a rehabilitation program was effective in reducing fatigue and anxiety, while improving quality of life in people with PASC.

Psychiatric disorders and the onset of self-reported fibromyalgia and chronic fatigue syndrome: The lifelines cohort study

Introduction

This study aimed to assess whether psychiatric disorders predict the onset of fibromyalgia and chronic fatigue syndrome (CFS) which develop in the presence of pre-existing muscle pain or fatigue.

Methods

The population-based Lifelines cohort study included 148,614 adults with relevant data for the fibromyalgia study and 136,423 for the CFS study. Participants with prior self-reported fibromyalgia (or CFS) at baseline were excluded from the relevant analysis. At follow-up (mean 2.4 years), new onsets of each syndrome were identified by self-report. Logistic regression was used to identify which of the baseline variables predicted new onsets of each syndrome. The total number of psychiatric disorders (depression, anxiety, burnout, panic disorder, social phobia, agoraphobia, obsessive-compulsive, and eating disorders) was used as a predictor. Prior to the analyses the samples were divided into those with and without marked muscle pain (for fibromyalgia analysis) or persistent fatigue (for CFS).

Results

During follow-up, there were 685/136,423 (0.5%) new onsets of self-reported FM in participants without marked muscle pain and 281/7481 (3.75%) in those with such pain; for CFS it was 292/124,223 (0.2%) for those without and 192/10,025 (1.9%) for those with baseline fatigue. In both univariate and logistic regression analyses of participants with prior persistent fatigue psychiatric disorder was clearly associated with onset of CFS. This was not so for onset of fibromyalgia in participants with prior muscle pain.

Discussion

Although psychiatric disorders did not predict self-reported fibromyalgia or CFS in participants free of pain or fatigue at baseline, in this study psychiatric disorder did predict self-reported CFS in the presence of pre-existing fatigue. Progress in understanding the etiology of these disorders may require studying separately onsets with and without pre-existing key symptoms.

Examining the variability of multiple daily symptoms over time among individuals with multiple long-term conditions (MLTC-M/multimorbidity): An exploratory analysis of a longitudinal smartwatch feasibility study

Introduction

People living with multiple long-term conditions (MLTC-M) (multimorbidity) experience a range of inter-related symptoms. These symptoms can be tracked longitudinally using consumer technology, such as smartphones and wearable devices, and then summarised to provide useful clinical insight.

Aim

We aimed to perform an exploratory analysis to summarise the extent and trajectory of multiple symptom ratings tracked via a smartwatch, and to investigate the relationship between these symptom ratings and demographic factors in people living with MLTC-M in a feasibility study.

Methods

'Watch Your Steps' was a prospective observational feasibility study, administering multiple questions per day over a 90 day period. Adults with more than one clinician-diagnosed long-term condition rated seven core symptoms each day, plus up to eight additional symptoms personalised to their LTCs per day. Symptom ratings were summarised over the study period at the individual and group level. Symptom ratings were also plotted to describe day-to-day symptom trajectories for individuals.

Results

Fifty two participants submitted symptom ratings. Half were male and the majority had LTCs affecting three or more disease areas (N = 33, 64%). The symptom rated as most problematic was fatigue. Patients with increased comorbidity or female sex seemed to be associated with worse experiences of fatigue. Fatigue ratings were strongly correlated with pain and level of dysfunction.

Conclusion

In this study we have shown that it is possible to collect and descriptively analyse self reported symptom data in people living with MLTC-M, collected multiple times per day on a smartwatch, to gain insights that might support future clinical care and research.

Physical and mental fatigue in people with non-communicable chronic diseases

BACKGROUND

Fatigue is frequently reported in people with a non-communicable chronic disease. More insight in the nature of this symptom may enhance targeted treatment of fatigue. In this study, we aimed to gain more insight in the prevalence of different types of fatigue and in current prescribed treatment strategies to reduce fatigue in non-communicable chronic diseases.

METHODS

People with non-communicable chronic diseases were contacted via public, non-profit, disease-specific health funds and patient associations and invited to complete a web-based survey. The survey included a general question about the experience ("Do you now or have you ever had complaints of fatigue?") and nature of fatigue (physically/mentally/combination), the Checklist Individual Strength-subscale subjective fatigue (CIS-Fatigue; 8-56 points), self-constructed questions for the distinction between physical and mental fatigue (both 3-21 points) and questions on prescribed treatments for fatigue.

RESULTS

In total, 4199 participants (77% females) completed the online survey. 3945 participants (94.0%) reported experiencing fatigue, of which 64.4% reported a combination of both physical and mental fatigue. Median CIS-Fatigue score was 41 (32-48) points, with 68% of the participants reporting severe fatigue (≥36 points). Median scores for physical and mental fatigue were 15 (11-18) and 12 (8-16) points, respectively. In 55% of the participants, fatigue was only occasionally or never discussed with the healthcare professional, and only 23% of the participants were prescribed a treatment for fatigue. Participants often reported no effect or even an increase in fatigue after treatment.

CONCLUSIONS

Findings indicate that both physical and mental fatigue are often experienced simultaneously in people with non-communicable chronic diseases, but can also occur separately. Fatigue is often only occasionally or never discussed, let alone treated, highlighting the need to raise awareness among healthcare professionals. Future studies are needed to gain more insight in underlying factors of fatigue in non-communicable chronic diseases, its impact on daily life and development and evaluation of targeted treatment strategies.Key messages:Both physical and mental fatigue are frequently present in people with non-communicable chronic diseases.Fatigue is often only occasionally or never discussed during consultation with the physician, highlighting the need to raise awareness among healthcare professionals for adequate screening and evaluating of fatigue in people with non-communicable chronic diseases.Only less than a quarter of the people with non-communicable chronic diseases who reported to experience fatigue were prescribed a treatment for fatigue, which was often experienced as ineffective.

Does resilience predict hospital length of stay after total knee arthroplasty? A prospective observational cohort study

Background

Resilience, or the ability to bounce back from stress, is a key psychological factor that is associated with ongoing functional independence and higher quality of life in older adults in the context of chronic health conditions. Emerging research has explored resilience and patient-reported outcomes after TKA. Our primary aim was to explore the relationship between resilience and acute hospital length of stay after total knee arthroplasty (TKA).

Methods

A prospective observational study recruited 75 participants one month before total knee arthroplasty from two Australian hospitals. Two preoperative psychological measures were used: the Brief Resilience Scale, and for comparison, the Depression, Anxiety and Stress Scale-21 (DASS-21). We collected sociodemographic, medical and surgical details, patient-reported pain, function, fatigue and quality of life one month before TKA. Health service data describing acute hospital length of stay, inpatient rehabilitation use, and physiotherapy occasions of service were collected after TKA. Non-parametric analysis was used to determine any differences in length of stay between those with low or high resilience and DASS-21 scores. Secondary regression analysis explored the preoperative factors affecting acute hospital length of stay.

Results

No significant difference was detected in length of stay between those with a low or a high resilience score before TKA. However, the group reporting psychological symptoms as measured by the DASS-21 before TKA had a significantly longer acute hospital length of stay after TKA compared to those with no psychological symptoms [median length of stay 6 (IQR 2.5) days vs. 5 (IQR 2) days, respectively (Mann-Whitney U = 495.5, P=0.03)]. Multivariate regression analysis showed that anesthetic risk score and fatigue were significant predictors of length of stay, with the overall model demonstrating significance (χ2=12.426, df = 4, P=0.014).

Conclusions

No association was detected between the brief resilience score before TKA and acute hospital length of stay after TKA, however, symptoms on the DASS-21 were associated with longer acute hospital length of stay. Preoperative screening for psychological symptoms using the DASS-21 is useful for health services to identify those at higher risk of longer acute hospital length of stay after TKA.

Efficacy and safety of fermented Prunus mume vinegar on fatigue improvement in adults with unexplained fatigue: A randomized controlled trial

Background

The accumulation of fatigue leads to reduced physical, emotional, psychological, and social functions.

Objectives

Fermented Prunus mume vinegar (PV) improves fatigue in animals; however, studies in humans have not been conducted. We aimed to examine the effects and safety of consuming fermented PV for 8 weeks on fatigue indices in adults with unexplained fatigue while considering the placebo effect.

Methods

A randomized, double-blind, placebo-controlled trial was conducted in adults of >19 years, who were diagnosed with unexplained fatigue for at least 1 month. Eighty participants were randomly assigned to receive daily 70 mL of fermented PV (2.56 mg/g, chlorogenic acid, and 15.3 mg/g, citric acid) or a placebo for 8 weeks. At baseline and 4 and 8 weeks after treatment, the participants were visited for blood tests (liver enzyme, glucose, creatinine, lactate, malondialdehyde [MDA], and creatine kinase [CK]) and questionnaires (Fatigue Severity Scale [FSS], fatigue visual analog scale [VAS], Beck Depression Inventory [BDI], the Korean version of the Brief Encounter Psychosocial Instrument [BEPSI-K], EQ-5D-3L, and EQ-VAS]).

Results

Fermented PV supplementation for 8 weeks did not remarkably improve the fatigue indices when compared to placebo. Additionally, differences in fatigue VAS, BDI, BEPSI-K, EQ-5D-3L, EQ-VAS, lactate, CK, and MDA concentrations between the groups were not observed. However, FSS had positively correlated with fatigue VAS, BDI, and BEPSI-K, whereas it was negatively correlated with EQ-5D-3L and EQ-VAS at the baseline and 8 weeks. None of the participants reported adverse events.

Conclusion

The efficacy of fermented PV did not exceed the efficacy of placebo in adults with unexplained fatigue.

Clinical trial registration

[ClinicalTrials.gov], identifier [NCT04319692].

A cross-sectional study on fatigue, anxiety, and symptoms of depression and their relation with medical status in adult patients with Marfan syndrome. Psychological consequences in Marfan syndrome

Marfan syndrome (MFS) is a connective tissue disorder affecting the cardiovascular, ocular, and skeletal system, which may be accompanied by psychological features. This study aimed to determine the prevalence of fatigue, anxiety, and symptoms of depression in MFS patients, and to assess the degree to which sociodemographic and clinical variables are associated with fatigue and psychological aspects. The prevalence of fatigue, anxiety, and symptoms of depression were assessed in two cohorts of MFS patients and compared with healthy controls. The checklist individual strength (CIS), and hospital anxiety and depression scale (HADS) questionnaires were utilized. Medical status was assessed (family history of MFS, aortic root dilatation >40 mm, previous aortic surgery, aortic dissection, chronic pain, skeletal involvement, and scoliosis). Severe fatigue was experienced by 37% of the total MFS cohort (n = 155). MFS patients scored significantly higher on the CIS questionnaire, concerning severe fatigue, as compared with the general Dutch population (p < 0.0001). There were no differences in HADS anxiety or depression scores. In older MFS patients, with a more severe cardiovascular phenotype, chronic pain, and a higher unemployment rate, significantly more symptoms of depression were observed, when compared with the general population (p = 0.027) or compared with younger MFS patients (p = 0.026). Multivariate analysis, showed that anxiety was associated with chronic pain (p = 0.022) and symptoms of depression with unemployment (p = 0.024). MFS patients report significantly more severe fatigue as compared with the general population. Since the cause of fatigue is unclear, more research may be needed. Psychological intervention, for example, cognitive behavioral therapy, may contribute to a reduction in psychological symptoms.

Longitudinal trajectories of fatigue in early RA: the role of inflammation, perceived disease impact and early treatment response

OBJECTIVE

Fatigue is common in rheumatoid arthritis (RA). We aimed to explore its longitudinal course, predictors and association with disease activity in early RA.

METHODS

Data came from the 2-year treat-to-target trial CareRA (Care in early RA) and its 3-year extension. Fatigue was measured on Visual Analogue Scale, Multidimensional Fatigue Inventory and Short Form-36 (SF-36) vitality. Longitudinal fatigue trajectories were identified with multivariate growth mixture modelling. Early predictors of fatigue and the association of fatigue and its trajectories with disease activity and clinical/psychosocial outcomes were studied with linear mixed models and multilevel mediation.

RESULTS

We included 356 and 244 patients in the 2-year and 5-year analyses, respectively. Four fatigue trajectories were identified: rapid, gradual, transient improvement and early deterioration, including 10%, 14%, 56% and 20% of patients. Worse pain, mental health and emotional functioning were seen in the early deterioration group. Higher pain, patient global assessment (PGA) and disability (Health Assessment Questionnaire), lower SF-36 mental components, and fewer swollen joints at baseline predicted higher fatigue over 5 years, while early disease remission strongly improved 5-year fatigue. The association between Simple Disease Activity Index and fatigue was mediated by PGA, pain, mental health and sleep quality.

CONCLUSIONS

Although fatigue evolves dynamically over time in early RA, most patients do not achieve sustained fatigue improvement despite intensive disease-modifying antirheumatic drug therapy. Higher 5-year fatigue levels were seen in patients with more perceived disease impact and fewer swollen joints at baseline. Conversely, early inflammatory disease control strongly improved long-term fatigue, pointing towards an early window of opportunity to prevent persistent fatigue.

Severe Fatigue in the First Year Following SARS-CoV-2 Infection: A Prospective Cohort Study

Background

Severe fatigue can persist for months after coronavirus disease 2019 (COVID-19) onset. This longitudinal study describes fatigue severity and its determinants up to 12 months after illness onset across the full spectrum of COVID-19 severity.

Methods

RECoVERED, a prospective cohort study in Amsterdam, the Netherlands, enrolled participants aged ≥16 years after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) diagnosis. Fatigue was measured using the validated Short Fatigue Questionnaire (SFQ; range 4–28) at months 1, 3, 6, 9, and 12 of follow-up. Fatigue severity was modeled over time using mixed-effects linear regression. Determinants of severe fatigue (SFQ ≥18) at 6 months since illness onset (ie, persistent fatigue) were identified using logistic regression.

Results

Between May 2020 and July 2021, 303 participants completed at least 1 fatigue questionnaire. Twelve months after illness onset, 17.4% (95% CI, 6.7% to 38.3%), 21.6% (95% CI, 11.2% to 37.7%), and 44.8% (95% CI, 28.0% to 62.9%) of participants with mild, moderate, and severe/critical COVID-19 (World Health Organization definition), respectively, experienced severe fatigue. When adjusting for age and sex, having ≥3 comorbidities (P = .007), severe/critical COVID-19 (P = .002), low mood (P < .001), and dyspnea in the first 2 weeks of illness (P = .001) were associated with more severe fatigue over time. Severe/critical COVID-19 (adjusted odds ratio [aOR], 3.37; 95% CI, 1.28 to 8.93) and low mood at enrollment (aOR, 2.43; 95% CI, 1.11 to 5.29) were associated with persistent fatigue. Recovery rarely occurred beyond 6 months after illness onset, regardless of COVID-19 severity.

Conclusions

The occurrence of severe fatigue in our cohort was high, especially among those with initially severe/critical COVID-19, with little recovery beyond 6 months after illness onset. Our findings highlight an urgent need for improved understanding of persistent severe fatigue following COVID-19 to help inform prevention and intervention.

Toward unraveling the correlates of fatigue in glioma

BACKGROUND

Even though fatigue is one of the most prevalent and burdensome symptoms in patients with glioma, its etiology and determinants are still poorly understood. We aimed to identify which demographic, tumor- and treatment-related characteristics and patient-reported outcome measures (PROMs) are associated with or are predictors of fatigue in glioma.

METHODS

In this retrospective observational study, we included glioma patients with preoperative and postoperative assessments including PROMs on fatigue, depression, cognitive functioning, and health-related quality of life (HRQoL). Linear mixed models were used to identify which clinical factors and PROMs were associated with fatigue and linear multiple regression was used to detect predictors of postoperative fatigue.

RESULTS

In this study, 222 patients were included (78% grade II-III glioma, 22% grade IV). These patients had performed 333 assessments (193 preoperative and 116 one year postoperatively). Of all assessments, 39% was indicative of severe fatigue. Several HRQoL domains, depression, and right-sided tumors were significantly associated with fatigue (marginal R 2 = 0.63). Contrary to common expectations, tumor type, treatment-related factors, and timing of the assessment, were not associated with fatigue. In a subgroup of 70 patients with follow-up assessments, preoperative fatigue, and physical functioning were predictors of postoperative fatigue (adjusted R 2 = 0.31).

CONCLUSION

Fatigue is a complex symptom, which should not solely be attributed to the tumor or its treatment, but is instead related to different aspects of mood and HRQoL. These insights are important in understanding fatigue and could guide symptom management, especially in patients with lower-grade tumors.