Fatigue and psychiatric disorder: different or the same?

The effect of intranasal (R,S)-ketamine on symptoms of fatigue in severe major depressive disorder or bipolar depression with and without comorbid alcohol use disorder: Results from a randomized, double-blind, placebo-controlled trial

BACKGROUND

Fatigue is a multidimensional condition that may overlap with depression. Initial studies found that fatigue responds in only a limited way to standard monoaminergic antidepressants and mood stabilizers but does respond positively to intravenous (IV) racemic (R,S)-ketamine (ketamine). However, IV ketamine's use is limited by cost and access barriers. To date, no study has evaluated intranasal (IN) ketamine in individuals with fatigue. This study sought to evaluate the anti-fatigue effects of a single 50 mg dose of IN ketamine in individuals with major depressive disorder (MDD) or bipolar depression (BDep), both with and without comorbid alcohol use disorder (AUD).

METHODS

Twenty-eight individuals with primary diagnoses of MDD or BDep I/II currently experiencing a depressive episode with active suicidality were enrolled; approximately 60 % had comorbid AUD. Changes in the NIH-Brief Fatigue Inventory (NIH-BFI) were assessed at baseline and at 4, 24, and 48 h post-treatment.

RESULTS

The group x time interaction for NIH-BFI score was significant (F = 3.44, p = 0.022), favoring IN ketamine over placebo. IN ketamine was well-tolerated with minimal adverse effects.

LIMITATIONS

Limitations include the limited sample size, short duration, and single, fixed dose.

CONCLUSIONS

IN ketamine appears to induce rapid anti-fatigue effects in individuals with severe MDD and BDep both with and without comorbid AUD. This suggests that IN ketamine holds potential as an alternative, rapid-acting, anti-fatigue option for different medical conditions.

Co-occurrence and symptomatology of fatigue and depression

OBJECTIVE

Fatigue and depression are highly comorbid phenotypes with partially overlapping symptoms. The main aims of the present study are to: (i) identify the risk of current fatigue and depression; (ii) determine if the depression symptoms experienced by individuals who are fatigued (N=766) and non-fatigued (N=1849) are different; and (iii) identify if the fatigue symptoms experienced by depressed (N=275) and non-depressed (N=2340) individuals are different, in a community-based sample of Australian twins aged over 50years.

METHODS

Fatigue and depression symptom profiles and classifications were generated using the Schedule of Fatigue and Anergia (SOFA); the General Health Questionnaire; and the Delusions-Symptoms-States Inventory, States of Anxiety and Depression questionnaires. The association between co-occurring fatigue and depression was assessed using prevalence ratios. Differences in the preponderance of fatigue and depression symptoms were assessed using logistic regression modeling.

RESULTS

Individuals with either fatigue or depression have an approximately two-fold increased risk for comorbid presentation of both traits, compared to the general population. Logistic regression analysis indicated that fatigued individuals were significantly more likely to report all of the Diagnostic and Statistical Manual of Mental Disorders (DSM) depression symptoms assessed in the study. Similarly, depressed individuals were significantly more likely to report all SOFA fatigue symptoms.

CONCLUSIONS

Fatigue and depression are highly correlated traits within the community. Depression symptomatology and prevalence are significantly increased in fatigued individuals. Fatigue and especially the symptoms of insomnia and poor concentration are strong predictors of depression. Notably, the association between fatigue and depression is independent of their overlapping symptomatology. Therefore, presentation with fatigue, and in particular the symptoms of insomnia and poor concentration, should be considered as warning signs of depression in older adults.

Somatisation as a risk factor for incident depression and anxiety

OBJECTIVE

In this study, we aimed to examine somatisation as a risk factor for the onset of depressive and anxiety disorders.

METHODS

4-year follow-up data from the Netherlands Study of Depression and Anxiety (NESDA), a multisite cohort study of the course of depression and anxiety, was analysed. Participants (18-65 years) without a lifetime depressive or anxiety disorder at baseline were included (n=611). Somatisation was measured at baseline with the somatisation subscale of the 4 Dimensional Symptoms Questionnaire. Onset of depression and anxiety was assessed with the CIDI interview at 2-year and 4-year follow-up.

RESULTS

Somatisation was a risk factor for the incidence of depression [Hazard Ratio per unit increase (HR); 95% Confidence Interval (CI): 1.13; 1.09-1.17] and anxiety [HR; 95% CI: 1.14; 1.09-1.18]. Associations attenuated but remained statistically significant after adjusting for socio-demographic characteristics, chronic somatic disorders, and baseline levels of (subclinical) depressive or anxiety symptoms [adjusted HR for depression; 95% CI: 1.06; 1.00-1.12, adjusted HR for anxiety; 95% CI: 1.13; 1.07-1.20].

CONCLUSION

Persons who somatise have an increased risk of becoming depressed or anxious in subsequent years, over and above baseline levels of depressive or anxiety symptoms. They may represent a target group for prevention of depressive and anxiety disorders.

Fatigue as prognostic risk marker of mental sickness absence in white collar employees

PURPOSE

To investigate fatigue as prognostic risk marker for identifying working employees at risk of long-term sickness absence (SA).

METHODS

At baseline, fatigue was measured in 633 white collar employees with the checklist individual strength (CIS) including scales for fatigue severity, reduced concentration, reduced motivation, and reduced physical activity. SA was medically certified by an occupational physician in the 3rd or 4th SA week with diagnostic codes according to the 10th version of the International Classification of Diseases. Medically certified SA was retrieved at the individual level from an occupational health register after 1-year follow-up. CIS scores were investigated as prognostic risk markers predicting medically certified SA and particularly SA certified as mental SA.

RESULTS

614 employees (N = 378 men and N = 236 women) had complete data and were eligible for analysis; 63 (10 %) had medically certified SA of whom 39 (6 %) had mental SA. Fatigue severity and total CIS scores were associated with medically certified SA in men, but poorly discriminated between men with and without medically certified SA. Fatigue severity, reduced concentration, reduced motivation, and total CIS scores were also associated with mental SA in men. CIS and its reduced concentration scale were valid prognostic risk markers of mental SA. CONCLUSION Fatigue was a prognostic risk marker of mental SA in white collar men. The CIS should be further validated as a screening tool for the risk of mental SA in white collar working populations.

Fatigue severity and factors associated with high fatigue levels in Korean patients with inflammatory bowel disease

Background/Aims

Many patients with inflammatory bowel disease (IBD) often complain of fatigue. To date, only a few studies in Western countries have focused on fatigue related to IBD, and fatigue has never been specifically studied in Asian IBD patients. The aim of the present study was to investigate the fatigue level and fatigue-related factors among Korean IBD patients.

Methods

Patients in remission or with mild to moderate IBD were included. Fatigue was assessed using the Functional Assessment of Chronic Illness Therapy-Fatigue and the Brief Fatigue Inventory. Corresponding healthy controls (HCs) also completed both fatigue questionnaires.

Results

Sixty patients with Crohn disease and 68 patients with ulcerative colitis (UC) were eligible for analysis. The comparison group consisted of 92 HCs. Compared with the HCs, both IBD groups were associated with greater levels of fatigue (p<0.001). Factors influencing the fatigue score in UC patients included anemia and a high erythrocyte sedimentation rate (ESR).

Conclusions

Greater levels of fatigue were detected in Korean IBD patients compared with HCs. Anemia and ESR were determinants of fatigue in UC patients. Physicians need to be aware of fatigue as one of the important symptoms of IBD to better understand the impact of fatigue on health-related quality of life.

Level and appraisal of fatigue are not specific in burnout

Fatigue is a main feature of the burnout syndrome but also very common in other psychiatric disorders such as major depression and anxiety disorders. This raises the question of whether the level and appraisal of fatigue is experienced differently by individuals suffering from burnout than by those exhibiting anxiety disorders and major depression. If fatigue is experienced differently in burnout compared with other disorders, this may clarify why fatigue is the main feature of the burnout syndrome. This knowledge may lead to the application of specific therapeutic interventions aimed at the experience of fatigue in burnout. In the present study, we investigated whether fatigue is experienced differently in burnout patients than in patients suffering from anxiety disorders or major depression. We presented 73 burnout patients, 67 depressed patients, 57 patients with an anxiety disorder and 127 healthy participants with a rating scale containing statements about the fatigue-performance relationship, and we assessed the level of fatigue, depression and anxiety. The level of fatigue reported by burnout patients was high but did not differ from that of the other patient groups. The appraisal of fatigue also did not differ among the patient groups. The burnout patients did not appraise their fatigue as a result of unrewarding activities nor did they catastrophize fatigue in an exceptional way. Thus, the level of fatigue and the appraisal of fatigue may be less relevant to the understanding of the specific pathological processes associated with burnout than is often presumed.

Manipulating the sleep-wake cycle and circadian rhythms to improve clinical management of major depression

BACKGROUND

Clinical psychiatry has always been limited by the lack of objective tests to substantiate diagnoses and a lack of specific treatments that target underlying pathophysiology. One area in which these twin failures has been most frustrating is major depression. Due to very considerable progress in the basic and clinical neurosciences of sleep-wake cycles and underlying circadian systems this situation is now rapidly changing.

DISCUSSION

The development of specific behavioral or pharmacological strategies that target these basic regulatory systems is driving renewed clinical interest. Here, we explore the extent to which objective tests of sleep-wake cycles and circadian function - namely, those that measure timing or synchrony of circadian-dependent physiology as well as daytime activity and nighttime sleep patterns - can be used to identify a sub-class of patients with major depression who have disturbed circadian profiles.

SUMMARY

Once this unique pathophysiology is characterized, a highly personalized treatment plan can be proposed and monitored. New treatments will now be designed and old treatments re-evaluated on the basis of their effects on objective measures of sleep-wake cycles, circadian rhythms and related metabolic systems.

Chronic fatigue and affective disorders in older adults: evidence from the 2007 British National Psychiatric Morbidity Survey

BACKGROUND

Although chronic fatigue is common in old age, the association between chronic fatigue and common affective disorders is largely unknown.

AIMS

To fill this research gap, the present study aims to determine the relationship between chronic fatigue and common psychiatric disorders among older adults aged 65 and older.

METHOD

A national representative sample of 1793 England community-dwelling respondents aged 65 and above was assessed in the 2007 Adult Psychiatric Morbidity Survey (APMS) using the Revised Clinical Interview Schedule to measure chronic fatigue and common psychiatric disorders. Demographic characteristics, medical conditions, and four health-related variables based on the Short Form 12 were also measured.

RESULTS

The prevalence of chronic fatigue was 18.6%. Bivariate analyses revealed that chronic fatigue was more common among women and non-white ethnicities. In addition, chronic fatigue was significantly related to depression, mixed anxiety and depressive disorder, and generalized anxiety disorder after adjusting for demographic variables, medical conditions, and four other health-related variables.

CONCLUSION

The prevalence rate of chronic fatigue in our sample is higher than a previous study. The psychiatric comorbidity of chronic fatigue supports the notion that chronic fatigue has a strong impact on quality of life in old age.

The role of cognitive, emotional and personality factors in the experience of fatigue in a university and community sample

The aim of this study was to investigate the contribution of cognitive, emotional and personality factors to the experience of fatigue severity in healthy adult individuals. Specifically, the study examined whether fatigue catastrophising and emotional distress mediated the relationships between neuroticism, general irrational and rational thoughts to fatigue severity. One hundred and eighty nine university students and community volunteers completed self-report questionnaires assessing fatigue catastrophising and symptom severity, neuroticism, general rational and irrational thoughts and emotional distress. A series of correlational and path analyses were conducted to test the study hypotheses. Neuroticism and more general negative, irrational cognitions were associated with elevated fatigue catastrophising and fatigue severity, whereas more adaptive, rational cognitions were related to lower fatigue catastrophising and fatigue severity. Both elevated fatigue catastrophising and emotional distress uniquely and simultaneously mediated the relationships between irrational and rational cognitions and neuroticism to fatigue severity. These findings demonstrate that cognitions play a role in fatigue severity. The results have implications in the assessment and treatment of fatigue disturbances in the general community.

Genetic co-morbidity between neuroticism, anxiety/depression and somatic distress in a population sample of adolescent and young adult twins

BACKGROUND

Genetic studies in adults indicate that genes influencing the personality trait of neuroticism account for substantial genetic variance in anxiety and depression and in somatic health. Here, we examine for the first time the factors underlying the relationship between neuroticism and anxiety/depressive and somatic symptoms during adolescence.

METHOD

The Somatic and Psychological Health Report (SPHERE) assessed symptoms of anxiety/depression (PSYCH-14) and somatic distress (SOMA-10) in 2459 adolescent and young adult twins [1168 complete pairs (35.4% monozygotic, 53% female)] aged 12-25 years (mean=15.5 ± 2.9). Differences between boys and girls across adolescence were explored for neuroticism, SPHERE-34, and the subscales PSYCH-14 and SOMA-10. Trivariate analyses partitioned sources of covariance in neuroticism, PSYCH-14 and SOMA-10.

RESULTS

Girls scored higher than boys on both neuroticism and SPHERE, with SPHERE scores for girls increasing slightly over time, whereas scores for boys decreased or were unchanged. Neuroticism and SPHERE scores were strongly influenced by genetic factors [heritability (h(2)) = 40-52%]. A common genetic source influenced neuroticism, PSYCH-14 and SOMA-10 (impacting PSYCH-14 more than SOMA-10). A further genetic source, independent of neuroticism, accounted for covariation specific to PSYCH-14 and SOMA-10. Environmental influences were largely specific to each measure.

CONCLUSIONS

In adolescence, genetic risk factors indexed by neuroticism contribute substantially to anxiety/depression and, to a lesser extent, perceived somatic health. Additional genetic covariation between anxiety/depressive and somatic symptoms, independent of neuroticism, had greatest influence on somatic distress, where it was equal in influence to the factor shared with neuroticism.

Systematic review: fatigue in inflammatory bowel disease

BACKGROUND

Fatigue is common, disabling yet underappreciated, in patients with chronic diseases, including inflammatory bowel disease (IBD).

AIMS

To examine the literature and determine the prevalence and patterns of fatigue in IBD patients, to identify opportunities and directions for future research in this area.

METHODS

A systematic review using PubMed and Ovid Medline databases was conducted using search terms 'fatigue', 'Crohn', 'colitis' and 'inflammatory bowel disease'. A review of fatigue in other similar chronic diseases was also performed.

RESULTS

Ten studies were found to include data on fatigue in IBD patients; all were conducted between 1999 and 2009. However, only one study (in children) measured fatigue in IBD patients as a primary outcome. In patients in remission, the prevalence of fatigue in IBD patients ranges from 41 to 48%. Data are sparse and conflicting on whether fatigue severity is proportional to disease severity/activity.

CONCLUSIONS

Despite the clinical reality of fatigue, there are few published studies examining fatigue in IBD as a primary outcome. More data are needed on the prevalence, correlation between disease activity and fatigue severity, and putative pathogenic pathways involved in fatigue pathogenesis, before ultimately elucidating targeted therapies for fatigue in IBD patients.

Perspectives on fatigue from the study of chronic fatigue syndrome and related conditions

Fatigue is a symptom whose causes are protean and whose phenotype includes physical, mood, and behavioral components. Chronic fatigue syndrome (CFS) is an illness that has strong biological underpinnings and no definite etiology. Diagnostic criteria established by the Centers for Disease Control and Prevention have helped classify CFS as an overlap of mood, behavioral, and biological components. These include the presence of fatigue for more than 6 months associated with a diminution of functional activity and somatic symptoms, and pain not attributable to a specific diagnosis or disease. Four of the following criteria need to be present: sore throat, impaired memory or cognition, unrefreshing sleep, postexertional fatigue, tender glands, aching stiff muscles, joint pain, and headaches. Many researchers have observed that CFS shares features in common with other somatic syndromes, including irritable bowel syndrome, fibromyalgia, and temporomandibular joint dysfunction. Correlations between inflammation and infection, augmented sensory processing, abnormalities of neurotransmitters, nerve growth factors, low levels of serotonin and norepinephrine, abnormalities of homeostasis of the stress system, and autonomic dysfunction may be hallmarks of CFS. The relative contributions of each of these abnormalities to the profound fatigue associated with CFS need to be explored further to better evaluate and treat the syndrome.

Neuropsychological functioning, illness perception, mood and quality of life in chronic fatigue syndrome, autoimmune thyroid disease and healthy participants

BACKGROUND

This study attempted to longitudinally investigate neuropsychological function, illness representations, self-esteem, mood and quality of life (QoL) in individuals with chronic fatigue syndrome (CFS) and compared them with both healthy participants and a clinical comparison group of individuals with autoimmune thyroid disease (AITD).

METHOD

Neuropsychological evaluation was administered at two time points, five weeks apart. Twenty-one individuals with CFS, 20 individuals with AITD and 21 healthy participants were matched for age, pre-morbid intelligence, education level and socio-economic status (SES). All groups also completed measures of illness perceptions, mood, self-esteem and QoL at both time points.

RESULTS

The CFS group showed significantly greater impairment on measures of immediate and delayed memory, attention and visuo-constructional ability, and reported significantly higher levels of anxiety and depression. After controlling for the effects of mood, the CFS group still demonstrated significant impairment in attention. The CFS group also reported significantly lower self-reported QoL than the AITD and healthy participants. In terms of illness perceptions, the AITD group believed that their condition would last longer, that they had more treatment control over their condition, and reported less concern than the CFS group.

CONCLUSIONS

These results suggest that the primary cognitive impairment in CFS is attention and that this is not secondary to affective status. The lower treatment control perceptions and greater illness concerns that CFS patients report may be causally related to their affective status.

Fatigue before and after mild traumatic brain injury: Pre–post-injury comparisons in relation toApolipoproteinE

PRIMARY OBJECTIVE

To assess the incidence of fatigue for persons following a mild traumatic brain injury (MTBI) and to evaluate the relationship between fatigue and APOE genotype. As fatigue is often found to be influenced by anxiety, depression and sleep disturbance, these factors were also measured.

METHODS AND PROCEDURES

Thirty-one persons who sustained a MTBI were drawn from a population-based longitudinal study. Each person who sustained a MTBI was matched by age, gender, education and APOE genotype with two non-head injury controls. Self-reported pre- and post-injury incidence of fatigue, anxiety, depression and sleep disturbance was compared within-group and between groups.

RESULTS

For the MTBI group, incidence of fatigue was almost twice as common post- than pre-injury, whereas there was no corresponding change in a non-injured control group. Within the MTBI-group, post-injury fatigue was particularly common for carriers of the APOE epsilon4 allele.

CONCLUSIONS

Fatigue is common sequela after a MTBI and especially pronounced for carriers of the APOE epsilon4 allele.

The relationship between fatigue and psychiatric disorders: evidence for the concept of neurasthenia

OBJECTIVE

Fatigue and psychiatric disorders frequently occur comorbidly and share similar phenomenological features. There has been debate as to whether chronic fatigue, or neurasthenia, should be considered an independent syndrome distinct from psychiatric disorders. We aimed to establish whether persistent fatigue can occur independently from psychiatric disorders and to test the hypothesis that fatigue without comorbid psychiatric symptoms has unique premorbid risk factors. We also aimed to investigate the psychological outcome of any individuals with fatigue.

METHODS

The MRC National Survey of Health and Development was used to prospectively follow 5362 participants from birth. A sample of nonfatigued individuals without psychiatric disorder was selected at age 36 and followed until age 43 years (n=2714). At age 43, the presence of new onset fatigue and/or psychiatric disorder was assessed. Information on a number of potential premorbid risk factors was collected between ages 0 and 36 years. Individuals with fatigue but no comorbid psychiatric disorder were then followed up at age 53 years.

RESULTS

At age 43 years, 201 (7.4%) participants reported significant levels of new onset fatigue in the absence of comorbid psychiatric disorder. Despite the absence of case level psychiatric disorder, these individuals did report increased levels of some psychological symptoms. Excessive childhood energy (adjusted OR 2.63, 95% CI 1.55-4.48, P<.001) and being overweight at age 36 (adjusted OR 1.62, 95% CI 1.05-2.49, P=.03) were specific risk factors for fatigue without psychiatric disorder but not fatigue with comorbid psychiatric illness. Neuroticism was a risk factor for fatigue both with and without comorbid psychiatric disorder. Negative life events and a family history of psychiatric illness were only risk factors for fatigue when it occurred comorbidly with psychiatric illness.

CONCLUSIONS

A significant proportion of the adult population will suffer from fatigue without comorbid psychiatric disorder. While fatigue and psychiatric disorders share some risk factors, excessive energy in childhood and being overweight as an adult appear to be specific risk factors for fatigue. Our results confirm the significant overlap between fatigue and psychiatric disorders, while also providing evidence for neurasthenia as a separate diagnosis.

Chronic fatigue: an evolutionary concept analysis

AIM

This paper is a report of a concept analysis of chronic fatigue.

BACKGROUND

Fatigue is a prevalent symptom encompassing both acute and chronic manifestations. It is chronic fatigue that is most problematic because of its duration and impact on life quality. The rise in prevalence of chronic conditions will result in a need to address coexistent symptoms, clarification of which is needed. Chronic fatigue is one of the most common symptoms in chronic illness. Clarification of the concept and an understanding of its use by discipline are needed.

DATA SOURCES

The evolutionary method of concept analysis was used to ascertain the attributes, antecedents, consequences and surrogate terms for chronic fatigue. A review of the literature published between 1966 and 2007 was carried out to determine the contextual use of the concept of chronic fatigue among disciplines. Sources used for this analysis included CINAHL, Medline, PsychINFO and Social Work Abstracts and the search yielded 66 papers.

RESULTS

The chronic fatigue experience is associated with a multitude of physical, psychological and social factors. The defining attributes of chronic fatigue are constancy, abnormality, whole-body experience, inexplicability and disabling. The antecedents of chronic fatigue are physical disease, psychopathology, female gender and a history of abuse. Consequences found include social isolation and stigmatization, physical inactivity, psychological disturbances and a reduced quality of life.

CONCLUSION

Further research is needed to identify the aetiology of chronic fatigue and to address the social context of living with this disabling symptom.

Effect of sertraline on symptoms and survival in patients with advanced cancer, but without major depression: a placebo-controlled double-blind randomised trial

BACKGROUND

Depression, anxiety, fatigue, and impaired wellbeing are common, important, and closely related in advanced cancer. We aimed to identify the effects of an established antidepressant on these symptoms and survival in patients with advanced cancer who did not have major depression as assessed by clinicians.

METHODS

Between July, 2001, and February, 2006, 189 patients with advanced cancer were randomly assigned sertraline 50 mg (n=95), or placebo (n=94), once per day. The primary outcome was depression as assessed by the Centre for Epidemiologic Studies Depression scale (CES-D); the main secondary outcomes were: anxiety as assessed by Hospital Anxiety and Depression Scales (HADS-A); overall quality of life and fatigue as assessed by Functional Assessment of Cancer Therapy General and Fatigue scales (FACT-G and FACT-F, respectively); and clinicians' ratings of quality of life by use of Spizter's Quality of Life Index (SQLI). Multiple measures were used for corroboration of the most important outcomes. Primary analyses were done by intention to treat and were based on scale scores at 4 weeks and 8 weeks. The benefits of sertraline compared with placebo are expressed on a range from +100 (ie, maximum benefit) to -100 (ie, maximum harm); a difference of 10 was deemed clinically significant. This clinical trial is registered at Current Controlled Trials website http://www.controlled-trials.com/ISRCTN72466475.

FINDINGS

Sertraline had no significant effect (scale, benefit over placebo [95% CI]) on depression (CES-D 0.4 [-2.6 to 3.4]), anxiety (HADS-A 2.0 [-1.5 to 5.5]), fatigue (FACT-F 0.3 [-4.3 to 4.9]), overall quality of life (FACT-G 1.7 [-1.3 to 4.7]), or clinicians' ratings (SQLI 2.0 [-2.5 to 6.5]), and the 95% CI ruled out a clinically significant benefit for all main outcomes. Sertraline was discontinued more often and earlier than was placebo (hazard ratio 1.46 [1.03-2.06], p=0.03). Recruitment was stopped after the first planned interim analysis in February 2006 (n=150) showed that survival was longer in patients assigned placebo than in patients assigned sertraline (unadjusted hazard ratio 1.60 [95% CI 1.04-2.45], log-rank p=0.04; adjusted hazard ratio 1.62 [1.06-2.41], Cox model p=0.02). However, at the final analysis in July 2006 of all patients (n=189) and with longer follow-up, survival did not differ significantly between the treatment groups (unadjusted hazard ratio 1.35 [0.95-1.91], log-rank p=0.09; adjusted hazard ratio 1.27 [0.87-1.84], Cox model p=0.20). The trial was closed because it had ruled out a significant benefit of sertraline.

INTERPRETATION

Sertraline did not improve symptoms, wellbeing, or survival in patients with advanced cancer who do not have major depression, and should be reserved for those with a proven indication.

How common is chronic fatigue syndrome; how long is a piece of string?

Commentary on

Prevalence of chronic fatigue syndrome in metropolitan, urban, and rural Georgia

William C Reeves, James F Jones, Elizabeth Maloney, Christine Heim, David C Hoaglin, Roumiana S Boneva, Marjorie Morrissey and Rebecca Devlin

The effect of cardiac rehabilitation exercise programs on feelings of energy and fatigue: a meta-analysis of research from 1945 to 2005

BACKGROUND

Physical activity is a healthful behavior that has promise for combating feelings of low energy and fatigue. Despite evidence suggesting that fatigue is a prodromal symptom of major cardiac events, improvements in feelings of energy and fatigue have largely been ignored by reviewers of cardiac rehabilitation literature who have focused on anxiety, depression and general measures of quality of life.

DESIGN

A meta-analytical review.

METHODS AND RESULTS

Computer databases were searched from January 1945 to May 2005 to identify relevant literature. A total of 36 studies consisting of 4765 subjects were included. Cardiac rehabilitation exercise programs were consistently associated with increases in energy and decreases in fatigue. The magnitude of the effect was moderately large (mean delta 0.51; 95% confidence interval 0.42-0.61) but was heterogeneous and modified by features of the research design. Comparison of effect sizes in cardiac rehabilitation studies concurrently measuring energy/fatigue, anxiety and depression suggest that exercise-based cardiac rehabilitation programs have larger effects on feelings of energy and fatigue compared with anxiety and depression.

CONCLUSION

This review quantifies the potential benefit of cardiac rehabilitation exercise programs on feelings of energy and fatigue, and suggests that cardiac rehabilitation researchers and practitioners may benefit from examining, and perhaps even focusing on, feelings of energy and fatigue as an important outcome variable. A greater understanding of the effect of cardiac rehabilitation exercise programs on feelings of energy and fatigue will be reached when more true experiments are conducted thereby avoiding the primary limitation of the literature reviewed; that is, the frequent use of non-experimental research designs.

The characteristics of fatigue in an older primary care sample

BACKGROUND

Primary care studies of younger adults have reported fatigue to be common and etiologically heterogeneous with both physical and psychological associations. This has led to considerable debate about whether fatigue may present independently of psychological disorder. Somatic symptoms in older people have been assumed to be almost entirely physical in origin.

AIMS

To determine the characteristics of fatigue and its relationship with psychological disorder in older primary care attenders.

METHOD

Ambulatory primary care patients aged 60 years and over completed self-report questionnaires and psychiatric interview at baseline and at 12 months.

RESULTS

The overall prevalence of fatigue was 27.4% with most, but not all, cases being comorbid with psychological disorder. Psychological disorder (OR, 8.43; 95% CI, 2.98-23.88) was a greater predictor of fatigue than physical illness (OR, 4.74; 95% CI, 1.63-13.85). Neither a tendency for fatigue to evolve into psychological disorder, nor vice versa, was observed longitudinally (overall kappa, 0.68; P<.001).

CONCLUSIONS

Fatigue is common in older primary care attenders and is not associated with physical illness alone. Despite the high rate of comorbidity with psychological disorder, independent and longitudinally stable forms of fatigue did present. The overall findings suggest that while fatigue does overlap with psychological phenomena, there may also be distinct forms of fatigue.

Is there an independent somatic symptom dimension in older people?

OBJECTIVE

In explaining the dimensions underlying nonpsychotic symptom reporting, traditional psychiatric paradigm has advocated a hierarchical model in which somatic symptoms are subsumed within two correlated psychological dimensions. A more recent alternate view is that somatic symptoms may be clearly separated from typical anxiety and depression symptoms if somatic symptoms are adequately recorded. The main aim of this study is to determine whether discrete somatic dimension(s) could be derived in older people.

METHOD

Exploratory factor analysis was used to determine the factor structure underlying the responses of 10662 ambulatory primary care patients, aged 60 years and over, who completed the 34-item SPHERE (Somatic and Psychological HEalth REport) questionnaire of somatic and psychological symptoms. In addition, weighted factor scores were compared according to whether there was a physical or psychological reason for presentation to a doctor.

RESULTS

A clinically interpretable four-factor solution, consisting of mood, cognitive, musculoskeletal, and fatigue symptoms, was derived. When factor analysis was repeated by gender, the only difference was that mood, cognitive, and pain-fatigue factors were derived in males. In the overall sample, all factor scores were higher in patients with a purely psychological reason for presentation.

CONCLUSION

Somatic symptoms could be measured independently of psychological symptoms in the current sample of older primary care patients.

The association between burnout and physical illness in the general population--results from the Finnish Health 2000 Study

OBJECTIVE

The association between burnout and physical diseases has been studied very little. The purpose of this study was to examine the relationship between burnout and physical illness in a representative nationwide population health study.

METHODS

As a part of the "Health 2000 Study" in Finland, 3368 employees aged 30-64 years were studied. Burnout was assessed with the Maslach Burnout Inventory-General Survey. Physical diseases were diagnosed in a comprehensive health examination by research physicians.

RESULTS

Physical illness was more common among subjects with burnout than others (64% vs. 54%, P<.0001), and the prevalence of diseases increased with the severity of burnout (P<.0001). Burnout was an important correlate of cardiovascular diseases among men (OR=1.35; 95% CI, 1.13-1.61) and musculoskeletal disorders among women (OR=1.22, 95% CI, 1.07-1.38) when adjusted for age, marital status, education, socioeconomic status, physical strenuousness of work, smoking, physical activity, alcohol consumption, body mass index, and depressive symptoms. The prevalence of musculoskeletal disorders and cardiovascular diseases increased with the severity of all three dimensions of burnout, that is, exhaustion (P<.0001 and P<.001, respectively), cynicism (P=.0001 and P<.001, respectively), and lack of professional efficacy (P<.01 and P<.0001, respectively).

CONCLUSIONS

Burnout is associated with musculoskeletal diseases among women and with cardiovascular diseases among men. These associations are not explained by sociodemographic factors, health behavior, or depression. Physical illnesses are associated with all three dimensions of burnout and not only with the exhaustion dimension. In the future, the causal relationships between burnout and physical diseases need to be investigated in prospective studies.

Direct and indirect relationships between emotional intelligence and subjective fatigue in university students

OBJECTIVE

The aim of this study was to examine the direct and indirect relationships between emotional intelligence and subjective fatigue.

METHODS

One hundred sixty seven university students completed questionnaires assessing subjective fatigue, emotional intelligence, and a range of other psychosocial factors. A series of regression analyses were used to examine the direct and indirect relationships between subjective fatigue and psychosocial factors.

RESULTS

Higher emotional intelligence was associated with less fatigue. The psychosocial variables depression, anxiety, optimism, internal health locus of control, amount of social support, and satisfaction with social support each partially mediated between emotional intelligence and fatigue. Additionally, sleep quality partially mediated between emotional intelligence and fatigue.

CONCLUSION

These findings regarding the association between subjective fatigue, emotional intelligence, and other psychosocial factors may facilitate an understanding of the aetiology of fatigue and contribute to future research examining interventions aimed at helping individuals cope with fatigue.

Chronic fatigue syndrome: an update focusing on phenomenology and pathophysiology

PURPOSE OF REVIEW

Chronic fatigue syndrome is a controversial condition especially concerning its clinical definition and aetiopathogenesis. Most recent research progress has been made in phenomenology and pathophysiology and we focused our review on these two areas.

RECENT FINDINGS

The phenomenology research supports the notion of a discrete fatigue syndrome which can be distinguished from depression and anxiety. The current case definition, however, may need an improvement based on empirical data. Recent advances in understanding the pathophysiology of chronic fatigue syndrome continue to demonstrate the involvement of the central nervous system. Hyperserotonergic state and hypoactivity of the hypothalamic-pituitary-adrenal axis constitute other findings, but the question of whether these alterations are a cause or consequence of chronic fatigue syndrome still remains unanswered. Immune system involvement in the pathogenesis seems certain but the findings on the specific mechanisms are still inconsistent. Genetic studies provide some evidence of the syndrome being a partly genetic condition, but environmental effects seem to be still predominant and identification of specific genes is still at a very early stage.

SUMMARY

The recent findings suggest that further research is needed in improving the current case definition; investigating overlaps and boundaries among various functional somatic syndromes; answering the question of whether the pathophysiologic findings are a cause or consequence; and elucidating the involvement of the central nervous system, immune system and genetic factors.

Chronic fatigue syndrome: the need for subtypes

Chronic fatigue syndrome (CFS) is an important condition confronting patients, clinicians, and researchers. This article provides information concerning the need for appropriate diagnosis of CFS subtypes. We first review findings suggesting that CFS is best conceptualized as a separate diagnostic entity rather than as part of a unitary model of functional somatic distress. Next, research involving the case definitions of CFS is reviewed. Findings suggest that whether a broad or more conservative case definition is employed, and whether clinic or community samples are recruited, these decisions will have a major influence in the types of patients selected. Review of further findings suggests that subtyping individuals with CFS on sociodemographic, functional disability, viral, immune, neuroendocrine, neurology, autonomic, and genetic biomarkers can provide clarification for researchers and clinicians who encounter CFS' characteristically confusing heterogeneous symptom profiles. Treatment studies that incorporate subtypes might be particularly helpful in better understanding the pathophysiology of CFS. This review suggests that there is a need for greater diagnostic clarity, and this might be accomplished by subgroups that integrate multiple variables including those in cognitive, emotional, and biological domains.

The neglect of somatoform disorders by old age psychiatry: some explanations and suggestions for future research

AIM

The somatoform disorders have long been ignored by old age psychiatry. The main aim of this paper is to identify and examine possible reasons for this neglect.

METHOD

A selective review of the general literature on somatoform disorders.

RESULTS

Significant conceptual, diagnostic and classificatory problems have impeded the consideration of somatoform disorders in older people. There is a perception that somatoform disorders are infrequent and have not been validated as independent clinical disorders. However, we present evidence that the more broadly defined somatoform disorders are common in all age groups in primary care and meet criteria for the determination of clinical validity. General difficulties in the assessment of psychiatric disorders in primary care, the setting in which somatoform disorders are most common, are compounded by a lack of support from old age psychiatry services. Effective psychological therapies may not be readily available to sufferers.

CONCLUSION

There is a need for change in the conceptualisation and nosology of the somatoform disorders. The formulation of age appropriate diagnostic criteria and presentations is a prerequisite for determining the clinical validity of these disorders in older people. This can be followed by study of their frequency, associated risk factors and treatment. A system of education that enhances the management of these disorders within primary care and old age psychiatry services is needed.

An epidemiological approach to study fatigue in the working population: the Maastricht Cohort Study

In 1998, a large scale prospective cohort study of prolonged fatigue in the working population was started in the Netherlands. The ultimate goal of this Maastricht Cohort Study was to identify risk factors involved in the aetiology and natural course of prolonged fatigue in the working population and to develop preventive measures and treatments that can be used in occupational health settings. In this paper, a conceptual model for epidemiological research on prolonged fatigue is presented. This model is the basis for the Maastricht Cohort Study. Alongside the model and design, the characteristics of the study population, the prevalence and one year cumulative incidence of prolonged fatigue, as well as its relation with secondary health outcomes (psychological distress, need for recovery, and burnout) are presented. Furthermore, model, design, and the presented results are discussed.

The association between chronic diseases and fatigue in the working population

OBJECTIVE

The aims of this study were to examine (a) whether employees with a chronic disease report more fatigue than employees without a chronic disease, (b) whether number or type of chronic disease is related to fatigue, and (c) whether differences in fatigue level in various types of chronic diseases are related to psychological distress.

METHODS

Data were taken from 12,137 employees. Fatigue was measured with the Checklist Individual Strength (CIS).

RESULTS

Employees with a chronic disease reported more fatigue (OR=2.9, 95% CI=2.7-3.2). Small differences were observed in the level of fatigue in various types of diseases. A strong linear association between the number of chronic diseases and fatigue was found. Psychological distress explained the higher level of fatigue in some chronic diseases (gastrointestinal diseases and migraine).

CONCLUSIONS

Fatigue is more common in employees with a chronic disease. A strong association between number of chronic diseases and fatigue exists. Fatigue in employees with a chronic disease can partly be explained by psychological distress. Some chronic diseases show a stronger association between psychological distress and fatigue.

Distinguishing between excessive daytime sleepiness and fatigue: toward improved detection and treatment

INTRODUCTION

Excessive daytime sleepiness (EDS) and fatigue occur in high percentages in the general population. They are common complaints in primary care and in specialty medicine. Although they may represent distinct or overlapping phenomena, the general medical literature does not normally distinguish between EDS and fatigue. Despite their prevalence, both EDS and fatigue are identified and treated in a relatively small proportion of those affected. The similarity of EDS and fatigue may create diagnostic ambiguity and thereby contribute to under-identification and under-treatment. Fatigue, in particular, is thought to be difficult to manage when it is identified.

METHODS

The literature was searched for reviews, meta-analysis and similar levels of papers focused on EDS or fatigue.

RESULTS

EDS and fatigue are operationalized in ways that contribute to blurring rather than to distinguishing between them. Existing measures of both EDS and fatigue may also contribute to their misidentification. Effective treatments for both symptoms have been established. Behavioral interventions are effective and underutilized.

DISCUSSION

We suggest more precise operationalization of EDS and fatigue, leading to a refinement of existing measures or development of new tools, a structured interview with fatigue and EDS sections in the clinical setting, and more consideration for behavioral interventions.

Predictors of fatigue in healthy young adults: moderating effects of cigarette smoking and gender

Fatigue is a common complaint of patients seen in primary care. Factors that contribute to fatigue in a patient population include poor health status, psychological stress, poor nutrition, and pregnancy. Less well understood are factors that contribute to fatigue among healthy, nonpregnant individuals. Within the framework of the theory of unpleasant symptoms, 40 healthy young smoking and nonsmoking adults between the ages of 18 and 35 were evaluated to determine self-report level of fatigue and contributing physiological, psychological, and situational factors. Results indicate that while self-report of fatigue did not vary in this population based on gender, subjects who were moderate to heavy cigarette smokers were significantly more fatigued than were nonsmokers (F = 10.24, df = 1, 38, P < 0.01), with the effect being specific to male smokers. Self-report of fatigue did not correlate with body mass index, baseline inflammatory or immune status, or blood pressure. Positive psychological and situational predictors of fatigue included depression (r = 0.556, P < 0.001), state anxiety (r = 0.569, P < 0.001), sleep quality (r = -0.399, P < 0.05), and sleep quantity (r = -0.411, P < 0.05). These results suggest that psychological and situational factors are key contributors to fatigue in young adults and that smoking is a risk factor for fatigue in men.

Prognosis of chronic fatigue in a community-based sample

OBJECTIVE

This study examined predictors of fatigue severity and predictors of continued chronic fatigue status at wave 2 follow-up within a random, community-based sample of individuals previously evaluated in a wave 1 prevalence study of chronic fatigue and chronic fatigue syndrome that originally took place between 1995 and 1997.

METHODS

Wave 1 data were from a larger community-based prevalence study of chronic fatigue syndrome. In the present study, a second wave of data were collected by randomly selecting a sample of participants from the wave 1 sample of 18,675 adults and readministering a telephone screening questionnaire designed to assess symptoms of chronic fatigue syndrome.

RESULTS

Findings revealed that wave 1 fatigue severity was a predictor of fatigue severity at wave 2 in the overall sample of individuals with and without chronic fatigue. In the smaller sample of individuals with chronic fatigue, wave 1 fatigue severity, worsening of fatigue with physical exertion, and feeling worse for 24 hours or more after exercise significantly predicted continued chronic fatigue status (vs. improvement) at wave 2 follow-up.

CONCLUSIONS

These findings underscore the prognostic validity of postexertional malaise in predicting long-term chronic fatigue and also highlight the importance of using population-based, representative random samples when attempting to identify long-term predictors of chronic fatigue at follow-up.

Lifestyle factors as risk factors for fatigue and psychological distress in the working population: prospective results from the Maastricht Cohort Study

We examined potentially modifiable lifestyle factors as possible risk factors for the onset of fatigue and psychological distress after 1-year follow-up among 8833 employees who participated in the prospective Maastricht Cohort Study of "Fatigue at Work." Results showed, even after adjustment for demographics, presence of disease, other lifestyle factors, psychosocial work characteristics, and psychological distress, that overweight (body mass index, 25 to 29.9) and being physically inactive during leisure time were strongly related to onset of fatigue in men, whereas underweight (body mass index, < 18.5) in women increased the risk for future fatigue. In addition, the study suggests some differential effects of lifestyle factors in the onset of psychological distress. Certainly, these modifiable factors can be targeted in interventions, either on an individual or group level, to prevent or at least reduce the risk of developing fatigue and psychological distress in the working population.

Chronic fatigue and anxiety/depression: a twin study

BACKGROUND

Up to three-quarters of patients with fatigue syndromes have comorbid mood or anxiety disorders, suggesting that chronic fatigue is a forme fruste of anxiety or depressive states.

AIMS

To establish whether the association of chronic fatigue with psychological distress is causal or due to a common genetic or environmental factor.

METHOD

69 monozygotic (MZ) and 31 dizygotic (DZ) female twin pairs, with only one co-twin reporting at least 6 months of fatigue, completed questions on fatigue, the General Health Questionnaire (GHQ) and a structured psychiatric interview. We examined the effects of three progressively more stringent definitions of chronic fatigue on four GHQ sub-scales.

RESULTS

Fatigued MZ and DZ twins by all definitions were significantly more depressed, anxious, somatically preoccupied and socially dysfunctional than their non-fatigued co-twins. Intrapair differences were similar in DZ and MZ twins, but non-significant differences were observed for the somatic symptoms and anxiety/insomnia sub-scales.

CONCLUSIONS

In this sample, chronic fatigue and psychological distress are strongly associated without evidence for genetic covariation, implying that the association is environmental, or due to overlapping definitions. Any genetic covariation missed is likely to involve anxiety rather than depression.

Cognitive and mood disturbance as causes and symptoms of fatigue in cancer patients

Fatigue, cognitive dysfunction, and depression are very common in cancer patients. A relationship among the three entities is recognized but poorly understood. Factors that contribute to this poor understanding are the subjective nature of the symptoms, multiple potential causes, and a lack of reliable assessment tools. An understanding of fatigue in cancer patients may benefit from studies of chronic fatigue syndrome (CFS) and other nonmalignant diseases indicating that cognitive impairment varies with physical and mental fatigue, and that symptoms of depression experienced by patients with physical illnesses and primary mood disorders are qualitatively different. The multidimensional nature of fatigue suggests that interventions should be patient-specific. They could be related to lifestyle or involve the use of specific behavioral or pharmacologic therapies. As is the case with depression and cognitive disorders, targeted interventions against cancer-related fatigue will benefit from a better understanding of its potential biologic causes. Consideration of cognitive dysfunction and depression complicates the understanding of cancer-related fatigue; however, it provides opportunities to assist patients who must deal with this serious problem.

Chronic fatigue syndrome: an update

The chronic fatigue syndrome is characterised by a fatigue that is disproportionate to the intensity of effort that is undertaken, has persisted for 6 months or longer, and has no obvious cause. Unless there has been a long period of patient- or physician-imposed inactivity, objective data may show little reduction in muscle strength or peak aerobic power, but the affected individual avoids heavy activity. The study of aetiology and treatment has been hampered by the low disease prevalence (probably <0.1% of the general population), and (until recently) by a lack of clear and standardised diagnostic criteria. It is unclear how far the aetiology is similar for athletes and nonathletes. It appears that in top competitors, overtraining and/or a negative energy balance can be precipitating factors. A wide variety of other possible causes and/or precipitating factors have been cited in the general population, including psychological stress, disorders of personality and affect, dysfunction of the hypothalamic-pituitary-adrenal axis, hormonal imbalance, nutritional deficits, immune suppression or activation and chronic infection. However, none of these factors have been observed consistently. The prognosis is poor; often disability and impairment of athletic performance are prolonged. Prevention of overtraining by careful monitoring seems the most effective approach in athletes. In those where the condition is established, treatment should aim at breaking the vicious cycle of effort avoidance, deterioration in physical condition and an increase in fatigue through a combination of encouragement and a progressive exercise programme.

Chronic unexplained fatigue

Fatigue is a common symptom in the community and the commonest associations are with stress or mood disturbance. One in a hundred people complain of unexplained and prolonged fatigue, with half that number meeting the strictest criteria for the chronic fatigue syndrome (CFS). Discrete fatigue syndromes have been described, particularly after Epstein Barr virus infection. The majority of patients with CFS have a syndrome similar to the ICD-10 definition of neurasthenia. Mood and somatoform disorders are common comorbid or differential diagnoses. The prognosis is poor, particularly in patients attending hospitals and those with comorbid psychiatric disorders. The aetiology of both CFS and chronic unexplained fatigue are essentially unknown, perhaps reflecting the heterogenenous natures of both the symptom and syndrome. There is reasonable evidence to suggest that particular infections may trigger both prolonged fatigue and CFS. Maintaining factors are different from triggering factors and include mood and sleep disorders, illness beliefs and behaviours, and possibly inactivity. Treatments aimed at reversing these maintaining factors show promise.