Identifying mindfulness and acceptance as mediators between negative affect, functional disability and emotional distress in patients with fibromyalgia.

OBJECTIVES: Fibromyalgia (FM) is a prevalent disabling condition characterised by chronic widespread pain. It is considered a complex illness in which the prognosis is conditioned by affective and cognitive mediators still largely unknown in FM. To investigate the correlation between psychological variables (acceptance, negative affect, and mindfulness) and functional disability or physical impact, anxiety/depression symptoms and emotional distress, and also to evaluate the mediating role of acceptance and mindfulness between negative affect, physical impact, anxiety/depression and emotional distress in individuals with FM. METHODS: Two hundred and fifty-one patients with FM who met the 2010 ACR criteria were included and filled out validated self-reported screening measures. The study explored Pearson's correlation coefficients and multiple mediation using a Preacher and Hayes's computational software tool, including the indirect effect associated with the two mediators (mindfulness and acceptance). RESULTS: Functional disability or physical impact, anxiety/depression symptoms and emotional distress correlated positively with negative affect (r= 0.580) and negatively with acceptance and mindfulness (r= -0.579 and r= -0.471; all p-values <0.001), respectively. The mediation analyses showed that acceptance and mindfulness mediated the relationship between negative affect and dependent variables such as physical impact, anxiety/depression symptoms and distress. CONCLUSIONS: The findings highlight that mindfulness and acceptance have a significant indirect effect on physical impact, anxiety/depression and emotional distress when controlling for negative affect as an independent variable in the FM patients. Future investigation should replicate and extend these outcomes in other study populations to determine the mediating role of mindfulness and acceptance in FM.

Association between psychological constructs and physical and emotional distress in individuals with fibromyalgia.

OBJECTIVES: Psychological factors and physical and emotional distress are frequently identified in fibromyalgia (FM). Previous reports have explored the relationship between some of these variables and functional disability and emotional distress in the disease; however, additional links with other potential psychological factors are unknown. This study aimed to assess the association between psychological variables and functional disability and emotional distress in individuals with FM. METHODS: This prospective, cross-sectional cohort study included 251 FM patients aged over 18 years. Demographic and clinical characteristics and outcome measures were recorded for each participant. Multiple linear regression analysis was performed to identify associations between the psychological factors. RESULTS: The findings suggest significant associations between psychological variables and physical impact and emotional distress (anxiety and depression) (all p-values < 0.0001). Positive and negative affect, mindfulness, and perceived injustice were strongly associated with the physical and emotional impact (all p-values < 0.05) in the sample. CONCLUSIONS: The study provides useful insights into the domains of physical and emotional distress. The findings should be incorporated into personalised treatments aimed at reducing functional disability and improving quality of life in patients with fibromyalgia.

Poor self-reported sleep quality and health-related quality of life in patients with chronic fatigue syndrome/myalgic encephalomyelitis.

Non-restorative sleep is a hallmark symptom of chronic fatigue syndrome/myalgic encephalomyelitis. However, little is known about self-reported sleep disturbances in these subjects. This study aimed to assess the self-reported sleep quality and its impact on quality of life in a Spanish community-based chronic fatigue syndrome/myalgic encephalomyelitis cohort. A prospective cross-sectional cohort study was conducted in 1,455 Spanish chronic fatigue syndrome/myalgic encephalomyelitis patients. Sleep quality, fatigue, pain, functional capacity impairment, psychopathological status, anxiety/depression and health-related quality of life were assessed using validated subjective measures. The frequencies of muscular, cognitive, neurological, autonomic and immunological symptom clusters were above 80%. High scores were recorded for pain, fatigue, psychopathological status, anxiety/depression, and low scores for functional capacity and quality of life, all of which correlated significantly (all p < 0.01) with quality of sleep as measured by the Pittsburgh Sleep Quality Index. Multivariate regression analysis showed that after adjusting for age and gender, the pain intensity (odds ratio, 1.11; p <0.05), psychopathological status (odds ratio, 1.85; p < 0.001), fibromyalgia (odds ratio, 1.39; p < 0.05), severe autonomic dysfunction (odds ratio, 1.72; p < 0.05), poor functional capacity (odds ratio, 0.98; p < 0.05) and quality of life (odds ratio, 0.96; both p < 0.001) were significantly associated with poor sleep quality. These findings suggest that this large chronic fatigue syndrome/myalgic encephalomyelitis sample presents poor sleep quality, as assessed by the Pittsburgh Sleep Quality Index, and that this poor sleep quality is associated with many aspects of quality of life.

Dimensional Personality Assessment among a Chronic Fatigue Syndrome (CFS) sample with Personality Inventory for DSM-5 (PID-5).

INTRODUCTION: Personality Disorders (PD) are highly prevalent among Chronic Fatigue Syndrome (CFS) patients, but studies based on the DSM-5 are still scarce. Validated instruments have not yet been specifically used in CFS patients. Therefore, our aim was to analyze the differences in personality facets and domains profiles among CFS patients with and without a PD using the Personality Inventory for DSM-5 (PID-5). Additionally, we analyzed the ability of this instrument to predict PD in a sample of CFS patients. This instrument is validated for PDs, but not for CFS. METHODS: All of the 84 CFS patients were evaluated through a clinical interview and underwent psychopathological evaluation with the SCID I and SCID II. Dimensional personality facets and domains were evaluated with the PID-5, according to DSM-5. RESULTS: In our sample, 54 (64%) of the patients fulfilled the criteria of a PD. The most significant facets in CFS with PD in comparison to those patients without a PD were Separation Insecurity, Perseveration, Withdrawal, Depressivity, Rigid Perfectionism, Unusual Beliefs and Experiences. Negative Affectivity and Detachment were the two significant domains in CFS-PD patients. In the regression analyses, only Detachment and Rigid Perfectionism constituted a prognostic factor leading to high probability of an endorsed PD. Conclussion. According to these results, the PID-5 domains and facets could be adequate and useful to differentiate between PD and non-PD patients in clinical samples and suggest a more frequent dimensional personality profile in CFS patients.

Comorbidity in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis: A Nationwide Population-Based Cohort Study.

BACKGROUND: Previous studies have shown evidence of comorbid conditions in chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME). OBJECTIVE: To estimate the prevalence of comorbidities and assess their associations using a nationwide population-based database of a Spanish CFS/ME cohort. METHOD: A nationally representative, retrospective, cross-sectional cohort study (2008-2015) assessed 1757 Spanish subjects who met both the 1994 Centers for Disease Control and Prevention/Fukuda definition and 2003 Canadian Criteria for CFS/ME. Sociodemographic and clinical data, comorbidities, and patient-reported outcome measures at baseline were recorded. A cluster analysis based on baseline clinical variables was performed to classify patients with CFS/ME into 5 categories according to comorbidities. A multivariate logistic regression analysis was conducted adjusting for potential confounding effects such as age and sex; response and categorical predictor variables were also assessed. RESULTS: A total of 1757 CFS/ME patients completed surveys were collected. We identified 5 CFS/ME clusters: group 1-fibromyalgia, myofascial pain, multiple chemical hypersensitivity, sicca syndrome, epicondylitis, and thyroiditis; group 2-alterations of ligaments and subcutaneous tissue, hypovitaminosis D, psychopathology, ligamentous hyperlaxity, and endometriosis. These 2 subgroups comprised mainly older women, with low educational level, unemployment, high levels of fatigue, and poor quality of life; group 3-with hardly any comorbidities, comprising mainly younger women, university students or those already employed, with lower levels of fatigue, and better quality of life; group 4-poorly defined comorbidities; and group 5-hypercholesterolemia. CONCLUSION: Over 80% of a large population-based cohort of Spanish patients with CFS/ME presented comorbidities. Among the 5 subgroups created, the most interesting were groups 1-3. Future research should consider multidisciplinary approaches for the management and treatment of CFS/ME with comorbid conditions.

Borderline Personality Disorder and Personality Inventory for DSM-5 (PID-5): Dimensional personality assessment with DSM-5.

INTRODUCTION: Borderline personality disorder (BPD) diagnosis has been considered highly controversial. The Diagnostic and Statistical Manual of Mental Disorders 5th edition (DSM-5) proposes an alternative hybrid diagnostic model for personality disorders (PD), and the Personality Inventory for DSM-5 (PID-5) has adequate psychometric properties and has been widely used for the assessment of the dimensional component. METHODS: Our aim was to analyze the utility of the personality traits presented in Section III of the DSM-5 for BPD diagnosis in an outpatient clinical sample, using the Spanish version of the PID-5. Two clinical samples were studied: BPD sample (n=84) and non-BPD sample (n=45). Between-sample differences in PID-5 scores were analyzed. RESULTS: The BPD sample obtained significantly higher scores in most PID-5 trait facets and domains. Specifically and after regression logistic analyses, in BPD patients, the domains of Negative Affectivity and Disinhibition, and the trait facets of emotional lability, [lack of] restricted affectivity, and impulsivity were more significantly associated with BPD. CONCLUSIONS: Although our findings are only partially consistent with the algorithm proposed by DSM-5, we consider that the combination of the PID-5 trait domains and facets could be useful for BPD dimensional diagnosis, and could further our understanding of BPD diagnosis complexity.

Childhood trauma in Chronic Fatigue Syndrome: focus on personality disorders and psychopathology.

INTRODUCTION: Personality Disorders (PDs) and childhood traumatic experiences have been considered risk factors for Chronic Fatigue Syndrome (CFS). However, the relationship between these factors and their associated psychopathological impact has not been explored in this population. This study was designed to evaluate the association between different childhood traumas and the presence and number of PDs and current psychopathology in a sample of CFS patients. MATERIAL AND METHODS: For this purpose, 166 CFS patients were evaluated with the Personality Diagnostic Questionnaire-4+ (PDQ-4+) and the Child Trauma Questionnaire. Other instruments were used to assess the associated psychopathology and the impact of fatigue. RESULTS: Of the total sample, 55 (33.1%) presented childhood trauma, the most frequent of which were emotional neglect (21.7%) and emotional abuse (18.1%). Considering PD presence, 79 (47.6%) patients presented some PD. There were no differences in frequency of physical childhood trauma in patients with and without PD. However, patients with PD had more frequently experienced emotional childhood trauma (OR=2.18, p=0.034). Severity of childhood trauma was related to a higher number of PDs, more severe depressive symptoms (p=0.025) and suicide risk (p=0.001). Patients with PD and any childhood trauma presented more severe depressive and irritable symptoms and a higher suicide risk than those without any PD and non-childhood traumatic event. These patients' psychopathological symptoms were similar to those of patients with childhood trauma and without PD. CONCLUSIONS: These results suggest that emotional childhood trauma but not physical childhood trauma is related to higher frequency of PD presence. More severe childhood emotional and physical traumas are related to a higher number of PDs and to more severe psychopathological symptoms.

Comorbid personality disorders in chronic fatigue syndrome patients: a marker of psychopathological severity.

INTRODUCTION: This study was designed to evaluate the presence of personality disorders (PDs) in Chronic Fatigue Syndrome (CFS) patients and to determine their influence on the severity of the associated psychopathology. METHODS: 132 CFS patients were assessed using SCID-I, Personality Diagnostic Questionnaire-4+ (PDQ-4+) with its Clinical Significance Scale, and Fatigue Impact Scale. The Beck Depression Inventory, Buss-Durkee Hostility Inventory and the State-Trait Anxiety Inventory were also administered. RESULTS: 48.5% patients presented PDs, being the most frequent the Obsessive-Compulsive and Avoidant ones. Patients with PDs had more depressive symptoms. Irritability, resentment, suspicion and guilt were the symptoms related with PDQ-4+ total score. CONCLUSIONS: According to these results, PDs may be frequent in CFS patients. This comorbidity is associated with a complex clinical profile, secondary to more severe psychiatric symptoms.

The role of neuroticism, perfectionism and depression in chronic fatigue syndrome. A structural equation modeling approach.

OBJECTIVE: Previous studies have reported consistent associations between Neuroticism, maladaptive perfectionism and depression with severity of fatigue in Chronic Fatigue Syndrome (CFS). Depression has been considered a mediator factor between maladaptive perfectionism and fatigue severity, but no studies have explored the role of neuroticism in a comparable theoretical framework. This study aims to examine for the first time, the role of neuroticism, maladaptive perfectionism and depression on the severity of CFS, analyzing several explanation models. METHODS: A sample of 229 CFS patients were studied comparing four structural equation models, testing the role of mediation effect of depression severity in the association of Neuroticism and/or Maladaptive perfectionism on fatigue severity. RESULTS: The model considering depression severity as mediator factor between Neuroticism and fatigue severity is the only one of the explored models where all the structural modeling indexes have fitted satisfactorily (Chi square=27.01, p=0.079; RMSE=0.047, CFI=0.994; SRMR=0.033). Neuroticism is associated with CFS by the mediation effect of depression severity. This personality variable constitutes a more consistent factor than maladaptive perfectionism in the conceptualization of CFS severity.

Improved estimation of the risk of manic relapse by combining clinical and brain scan data.

INTRODUCTION: Estimating the risk of manic relapse could help the psychiatrist individually adjust the treatment to the risk. Some authors have attempted to estimate this risk from baseline clinical data. Still, no studies have assessed whether the estimation could improve by adding structural magnetic resonance imaging (MRI) data. We aimed to evaluate it. MATERIAL AND METHODS: We followed a cohort of 78 patients with a manic episode without mixed symptoms (bipolar type I or schizoaffective disorder) at 2-4-6-9-12-15-18 months and up to 10 years. Within a cross-validation scheme, we created and evaluated a Cox lasso model to estimate the risk of manic relapse using both clinical and MRI data. RESULTS: The model successfully estimated the risk of manic relapse (Cox regression of the time to relapse as a function of the estimated risk: hazard ratio (HR)=2.35, p=0.027; area under the curve (AUC)=0.65, expected calibration error (ECE)<0.2). The most relevant variables included in the model were the diagnosis of schizoaffective disorder, poor impulse control, unusual thought content, and cerebellum volume decrease. The estimations were poorer when we used clinical or MRI data separately. CONCLUSION: Combining clinical and MRI data may improve the risk of manic relapse estimation after a manic episode. We provide a website that estimates the risk according to the model to facilitate replication by independent groups before translation to clinical settings.

[Concomitant lithium and methadone treatment in a bipolar patient: a case report]. / Tratamiento concomitante de litio y metadona en un paciente bipolar: a propósito de un caso.

Dual diagnosis requires complex therapeutic approaches to adapt treatment to the dual nature of the problem. It is important to understand the drug effects and the drug interactions that may be observed during the integral treatment of these pathologies. Given the scarcity of data on the effects of lithium and methadone treatment, the aim of this clinical case report is to explain the interactions produced between methadone and lithium carbonate, in a female patient with medical multi-pathology, opioid-dependent and with comorbid bipolar disorder, who was treated with both drugs. The most common adverse effects for each drug are described. Drug interactions and temporal correspondence of the two drugs, as well as their dosages, are described through review of the retrospective chart and prospective follow-up of the patient. After one year of follow-up the patient had experienced no interactions in the concomitant lithium and methadone treatment. It should be noted that treatment of bipolar patients with dual diagnosis is complex, and should only be carried out by experts.

Treatment and management of chronic fatigue syndrome/myalgic encephalomyelitis: all roads lead to Rome.

This review explores the current evidence on benefits and harms of therapeutic interventions in chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) and makes recommendations. CFS/ME is a complex, multi-system, chronic medical condition whose pathophysiology remains unknown. No established diagnostic tests exist nor are any FDA-approved drugs available for treatment. Because of the range of symptoms of CFS/ME, treatment approaches vary widely. Studies undertaken have heterogeneous designs and are limited by sample size, length of follow-up, applicability and methodological quality. The use of rintatolimod and rituximab as well as counselling, behavioural and rehabilitation therapy programs may be of benefit for CFS/ME, but the evidence of their effectiveness is still limited. Similarly, adaptive pacing appears to offer some benefits, but the results are debatable: so is the use of nutritional supplements, which may be of value to CFS/ME patients with biochemically proven deficiencies. To summarize, the recommended treatment strategies should include proper administration of nutritional supplements in CFS/ME patients with demonstrated deficiencies and personalized pacing programs to relieve symptoms and improve performance of daily activities, but a larger randomized controlled trial (RCT) evaluation is required to confirm these preliminary observations. At present, no firm conclusions can be drawn because the few RCTs undertaken to date have been small-scale, with a high risk of bias, and have used different case definitions. Further, RCTs are now urgently needed with rigorous experimental designs and appropriate data analysis, focusing particularly on the comparison of outcomes measures according to clinical presentation, patient characteristics, case criteria and degree of disability (i.e. severely ill ME cases or bedridden).

Gender differences in chronic fatigue syndrome.

BACKGROUND AND OBJECTIVES: Chronic fatigue syndrome (CFS) is a chronic condition that predominantly affects women. To date, there are few epidemiologic studies on CFS in men. The objective of the study was to assess whether there are gender-related differences in CFS, and to define a clinical phenotype in men. PATIENTS AND METHODS: A prospective, cross-sectional cohort study was conducted including CFS patients at the time of diagnosis. Sociodemographic data, clinical variables, comorbid phenomena, fatigue, pain, anxiety/depression, and health quality of life, were assessed in the CFS population. A comparative study was also conducted between genders. RESULTS: The study included 1309 CFS patients, of which 119 (9.1%) were men. The mean age and symptoms onset were lower in men than women. The subjects included 30% single men vs. 15% single women, and 32% of men had specialist work vs. 20% of women. The most common triggering factor was an infection. Widespread pain, muscle spasms, dizziness, sexual dysfunction, Raynaud's phenomenon, morning stiffness, migratory arthralgias, drug and metals allergy, and facial oedema were less frequent in men. Fibromyalgia was present in 29% of men vs. 58% in women. The scores on physical function, physical role, and overall physical health of the SF-36 were higher in men. The sensory and affective dimensions of pain were lower in men. CONCLUSIONS: The clinical phenotype of the men with CFS was young, single, skilled worker, and infection as the main triggering agent. Men had less pain and less muscle and immune symptoms, fewer comorbid phenomena, and a better quality of life.

Effect of coenzyme Q10 plus nicotinamide adenine dinucleotide supplementation on maximum heart rate after exercise testing in chronic fatigue syndrome - A randomized, controlled, double-blind trial.

BACKGROUND & AIMS: Chronic Fatigue Syndrome (CFS) is a complex condition, characterized by severe disabling fatigue with no known cause, no established diagnostic tests, and no universally effective treatment. Several studies have proposed symptomatic treatment with coenzyme Q10 (CoQ10) and nicotinamide adenine dinucleotide (NADH) supplementation. The primary endpoint was to assess the effect of CoQ10 plus NADH supplementation on age-predicted maximum heart rate (max HR) during a cycle ergometer test. Secondary measures included fatigue, pain and sleep. METHODS: A proof-of-concept, 8-week, randomized, controlled, double-blind trial was conducted in 80 CFS patients assigned to receive either CoQ10 plus NADH supplementation or matching placebo twice daily. Maximum HR was evaluated at baseline and at end of the run-in period using an exercise test. Fatigue, pain and sleep were evaluated at baseline, and then reassessed at 4- and 8-weeks through self-reported questionnaires. RESULTS: The CoQ10 plus NADH group showed a significant reduction in max HR during a cycle ergometer test at week 8 versus baseline (P = 0.022). Perception of fatigue also showed a decrease through all follow-up visits in active group versus placebo (P = 0.03). However, pain and sleep did not improve in the active group. Coenzyme Q10 plus NADH was generally safe and well tolerated. CONCLUSIONS: Our results suggest that CoQ10 plus NADH supplementation for 8 weeks is safe and potentially effective in reducing max HR during a cycle ergometer test and also on fatigue in CFS. Further additional larger controlled trials are needed to confirm these findings. Clinical trial registrationThis trial was registered at clinicaltrials.gov as NCT02063126.

Does oral coenzyme Q10 plus NADH supplementation improve fatigue and biochemical parameters in chronic fatigue syndrome?

Chronic fatigue syndrome (CFS) is a chronic and extremely debilitating illness characterized by prolonged fatigue and multiple symptoms with unknown cause, diagnostic test, or universally effective treatment. Inflammation, oxidative stress, mitochondrial dysfunction, and CoQ10 deficiency have been well documented in CFS. We conducted an 8-week, randomized, double-blind placebo-controlled trial to evaluate the benefits of oral CoQ10 (200 mg/day) plus NADH (20 mg/day) supplementation on fatigue and biochemical parameters in 73 Spanish CFS patients. This study was registered in ClinicalTrials.gov (NCT02063126). A significant improvement of fatigue showing a reduction in fatigue impact scale total score (p<0.05) was reported in treated group versus placebo. In addition, a recovery of the biochemical parameters was also reported. NAD+/NADH (p<0.001), CoQ10 (p<0.05), ATP (p<0.05), and citrate synthase (p<0.05) were significantly higher, and lipoperoxides (p<0.05) were significantly lower in blood mononuclear cells of the treated group. These observations lead to the hypothesis that the oral CoQ10 plus NADH supplementation could confer potential therapeutic benefits on fatigue and biochemical parameters in CFS. Larger sample trials are warranted to confirm these findings.

Relationship between poor decision-making process and fatigue perception in Parkinson's disease patients.

BACKGROUND: Fatigue is a common non-motor symptom in Parkinson's disease patients. The reasons for its perception are not completely understood. One suggested possibility might be that perceived fatigue is related with abnormal interpretation of somatic symptoms. It has been described that somatic markers misinterpretation leads to poor decision-making. We hypothesized that fatigued Parkinson's disease patients would show poorer performance than non-fatigued in a decision-making task. METHODS: To test our hypothesis, 89 Parkinson's disease patients were assessed for the presence of fatigue using the Parkinson Fatigue Scale. All patients were also administered scales evaluating psychopathology and neuropsychological tests, including the Iowa Gambling Task. RESULTS: 33 (37.1%) patients fulfilled the established criteria for fatigue. In the univariate analysis, fatigued patients showed higher levels of anxiety (state: p = 0.001, trait: p < 0.001), impulsivity (p = 0.051), and depression (p < 0.001) than non-fatigued patients. No statistically significant differences in other neuropsychological test results (Stroop, Trail Making Test, Tower of London) were found between fatigued and non-fatigued patients except for the Iowa Gambling Task, in which fatigued patients showed poorer performance (p = 0.001) after controlling for confounding factors. CONCLUSIONS: These results suggest that fatigued Parkinson's disease patients may present abnormal decision-making process, which may reflect abnormal processing of somatic markers when faced with an activity that requires effort.

[Impact of the fibromyalgia in the chronic fatigue syndrome]. / Impacto de la fibromialgia en el síndrome de fatiga crónica.

BACKGROUND AND OBJECTIVE: Different studies have showed association of the chronic fatigue syndrome (CFS) with other pathologies, including fibromyalgia (FM). The objective of this study is to analyze whether there are differences in the clinic and in the assessment of fatigue in CFS patients associated or not with FM. PATIENTS AND METHODS: A cross-sectional, single-site observational study was undertaken on a consecutive cases of a register of CFS patients at CFS Unit in Vall d'Hebron Hospital, Barcelona, from January 2008 until March 2011. The variables analyzed were FM comorbidity, sleep and fatigue characteristics and cognitive, neurological and autonomic symptoms. Questionnaires of fatigue impact scale, fatigue strength and impact on quality of life SF-36 were evaluated. RESULTS: We included 980 CFS patients (mean age: 48±9 years; 91% women). Fibromyalgia was present in 528 patients (54%). The level of fatigue (P=.001) and pain (P<.001) was higher in FM patients. Patients with CFS and FM had more prevalence of sleep-related phenomena. The percentage of patients and the degree of severity of cognitive symptoms, neurological and autonomic dysfunction was higher in FM patients (P<.001). FM patients scored higher on the fatigue impact scale (P<.001) and showed worse results in the quality of life questionnaire (P<.001). CONCLUSIONS: FM co-morbidity worse clinical parameters, fatigue and the perception of quality of life in CFS patients.

Chronic fatigue syndrome and personality: a case-control study using the Alternative Five Factor Model.

Neuroticism is the personality dimension most frequently associated with chronic fatigue syndrome (CFS). Most studies have also shown that CFS patients are less extraverted than non-CFS patients, but results have been inconsistent, possibly because the facets of the extraversion dimension have not been separately analyzed. This study has the following aims: to assess the personality profile of adults with CFS using the Alternative Five-Factor Model (AFFM), which considers Activity and Sociability as two separate factors of Extraversion, and to test the discriminant validity of a measure of the AFFM, the Zuckerman-Kuhlman Personality Questionnaire, in differentiating CFS subjects from normal-range matched controls. The CFS sample consisted of 132 consecutive patients referred for persistent fatigue or pain to the Department of Medicine of a university hospital. These were compared with 132 matched normal population controls. Significantly lower levels of Activity and significantly higher levels of Neuroticism-Anxiety best discriminated CFS patients from controls. The results are consistent with existing data on the relationship between Neuroticism and CFS, and clarify the relationship between Extraversion and CFS by providing new data on the relationship of Activity to CFS.

The association of apathy with central fatigue perception in patients with Parkinson's disease.

This study was designed to evaluate the association of different apathy conceptual domains with central fatigue perception in Parkinson's disease (PD), taking into consideration other nonmotor symptoms. To this end, 90 consecutive PD patients (66.7% men, mean age 61.44 ± 13.2 years) underwent a comprehensive neurological and psychiatric examination, including the Structured Clinical Interview for DSM-IV, Parkinson Fatigue Scale, Lille Apathy Rating Scale, Hamilton Depression Scale, and State-Trait Anxiety Inventory. A linear regression model was applied to analyze the relationship between apathy and its different conceptual domains with fatigue severity. Thirty-seven (41.1%) patients presented fatigue. Its presence was associated with higher apathy total scores and with 2 of the 4 apathy conceptual domains (less intellectual curiosity and action initiation) with no associations in the emotion and self-awareness apathy domains. Patients with fatigue scored higher in depression (p < .001), anxiety trait (p < .001), and anxiety state (p = .006). Regression analysis identified that Lille Apathy Rating Scale total score (p = .008), intellectual curiosity and action initiation apathy subscores (p = .001 and p = .003) were associated with fatigue severity in patients with right predominant motor symptoms. Sex, age, disease duration, clinical stage, motor complications, prior psychiatric disorders, and treatment were not significantly associated with presence of fatigue. The findings suggest that some apathy-related domains are more frequent in fatigued PD and may be related with fatigue severity.

Could mitochondrial dysfunction be a differentiating marker between chronic fatigue syndrome and fibromyalgia?

Chronic fatigue syndrome (CFS) and fibromyalgia (FM) are complex and serious illnesses that affect approximately 2.5% and 5% of the general population worldwide, respectively. The etiology is unknown; however, recent studies suggest that mitochondrial dysfunction has been involved in the pathophysiology of both conditions. We have investigated the possible association between mitochondrial biogenesis and oxidative stress in patients with CFS and FM. We studied 23 CFS patients, 20 FM patients, and 15 healthy controls. Peripheral blood mononuclear cell showed decreased levels of Coenzyme Q10 from CFS patients (p<0.001 compared with controls) and from FM subjects (p<0.001 compared with controls) and ATP levels for CFS patients (p<0.001 compared with controls) and for FM subjects (p<0.001 compared with controls). On the contrary, CFS/FM patients had significantly increased levels of lipid peroxidation, respectively (p<0.001 for both CFS and FM patients with regard to controls) that were indicative of oxidative stress-induced damage. Mitochondrial citrate synthase activity was significantly lower in FM patients (p<0.001) and, however, in CFS, it resulted in similar levels than controls. Mitochondrial DNA content (mtDNA/gDNA ratio) was normal in CFS and reduced in FM patients versus healthy controls, respectively (p<0.001). Expression levels of peroxisome proliferator-activated receptor gamma-coactivator 1-alpha and transcription factor A, mitochondrial by immunoblotting were significantly lower in FM patients (p<0.001) and were normal in CFS subjects compared with healthy controls. These data lead to the hypothesis that mitochondrial dysfunction-dependent events could be a marker of differentiation between CFS and FM, indicating the mitochondria as a new potential therapeutic target for these conditions.