Tag: psychiatric disorders

Therapeutic Implications of the Microbial Hypothesis of Mental Illness

Abstract:

There is increasingly compelling evidence that microorganisms may play an etiological role in the emergence of mental illness in a subset of the population. Historically, most work has focused on the neurotrophic herpesviruses, herpes simplex virus type 1 (HSV-1), cytomegalovirus (CMV), and Epstein-Barr virus (EBV) as well as the protozoan, Toxoplasma gondii. In this chapter, we provide an umbrella review of this literature and additionally highlight prospective studies that allow more mechanistic conclusions to be drawn.

Next, we focus on clinical trials of anti-microbial medications for the treatment of psychiatric disorders. We critically evaluate six trials that tested the impact of anti-herpes medications on inflammatory outcomes in the context of a medical disorder, nine clinical trials utilizing anti-herpetic medications for the treatment of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) or schizophrenia, and four clinical trials utilizing anti-parasitic medications for the treatment of schizophrenia.

We then turn our attention to evidence for a gut dysbiosis and altered microbiome in psychiatric disorders, and the potential therapeutic effects of probiotics, including an analysis of more than 10 randomized controlled trials of probiotics in the context of schizophrenia, bipolar disorder (BD), and major depressive disorder (MDD).

Source: Savitz J, Yolken RH. Therapeutic Implications of the Microbial Hypothesis of Mental Illness. Curr Top Behav Neurosci. 2022 May 24. doi: 10.1007/7854_2022_368. Epub ahead of print. PMID: 35606640. https://pubmed.ncbi.nlm.nih.gov/35606640/

Effect of psychiatric disorders on outcome of cognitive-behavioural therapy for chronic fatigue syndrome

Abstract:

Psychiatric disorders have been associated with poor outcome in individuals with chronic fatigue syndrome (CFS). This study examines the impact of psychiatric disorders on outcome of cognitive-behavioural therapy (CBT). Psychiatric diagnoses were assessed with a structured psychiatric interview in a CBT trial of 270 people with CFS. Lifetime and current psychiatric disorders were found in 50 and 32% respectively. No significant differences in fatigue severity and functional impairment following treatment were found between participants with and without psychiatric diagnoses.

 

Source: Prins J, Bleijenberg G, Rouweler EK, van der Meer J. Effect of psychiatric disorders on outcome of cognitive-behavioural therapy for chronic fatigue syndrome. Br J Psychiatry. 2005 Aug;187:184-5. http://bjp.rcpsych.org/content/187/2/184.long (Full article)

 

Chronic fatigue syndrome, chronic fatigue, and psychiatric disorders: predictors of functional status in a national nursing sample

Abstract:

Members of 2 nurses’ associations (N = 71) were assessed using 2 mail questionnaires, a telephone questionnaire, the Diagnostic Interview Schedule, and medical records. Physicians reviewed participants to determine whether they met current criteria for chronic fatigue syndrome(CFS). Stepwise multivariate regression analyses were conducted to identify predictors of functional status scores.

Impairments in physical, role, and social functioning increased as fatigue severity increased. Bodily pain increased as fatigue severity increased, and ratings of overall health increased as severity of fatigue decreased. Nurses with a current psychiatric diagnosis reported more impairments in emotional functioning than nurses with a lifetime diagnosis or no psychiatric diagnosis.

Quality of life decreased as fatigue severity increased. Nurses with fatigue not meeting CFS criteria reported better quality of life than those with CFS or medical exclusions.

 

Source: Wagner-Raphael LI, Jason LA, Ferrari JR. Chronic fatigue syndrome, chronic fatigue, and psychiatric disorders: predictors of functional status in a national nursing sample. J Occup Health Psychol. 1999 Jan;4(1):63-71. http://www.ncbi.nlm.nih.gov/pubmed/10100114

 

Physical fatigability and exercise capacity in chronic fatigue syndrome: association with disability, somatization and psychopathology

Abstract:

Physical fatigability and avoidance of physically demanding tasks in chronic fatigue syndrome (CFS) were assessed by the achievement or nonachievement of 85% of age-predicted maximal heart rate (target heart rate, THR) during incremental exercise. The association with functional status impairment, somatization, and psychopathology was examined.

A statistically significant association was demonstrated between this physical fatigability variable and impairment, and a trend was found for an association with somatization. No association was demonstrated with psychopathology. These results are in accordance with the cognitive-behavioral model of CFS, suggesting a major contribution of avoidance behavior to functional status impairment; however, neither anxiety nor depression seem to be involved in the avoidance behavior.

Aerobic work capacity was compared between CFS and healthy controls achieving THR. Physical deconditioning with early involvement of anaerobic metabolism was demonstrated in this CFS subgroup.

Half of the CFS patients who did not achieve THR did not reach the anaerobic threshold. This finding argues against an association in CFS between avoidance of physically demanding tasks and early anaerobic metabolism during effort.

 

Source: Fischler B, Dendale P, Michiels V, Cluydts R, Kaufman L, De Meirleir K. Physical fatigability and exercise capacity in chronic fatigue syndrome: association with disability, somatization and psychopathology. J Psychosom Res. 1997 Apr;42(4):369-78. http://www.ncbi.nlm.nih.gov/pubmed/9160276

 

The prognosis of chronic fatigue and chronic fatigue syndrome: a systematic review

Abstract:

The prognosis of chronic fatigue syndrome and chronic fatigue has been studied in numerous small case series. We performed a systematic review of all studies to determine the proportion of individuals with the conditions who recovered at follow-up, the risk of developing alternative physical diagnoses, and the risk factors for poor prognosis.

A literature search of all published studies which included a follow-up of patients with chronic fatigue syndrome or chronic fatigue were performed. Of 26 studies identified, four studied fatigue in children, and found that 54-94% of children recovered over the periods of follow-up. Another five studies operationally defined chronic fatigue syndrome in adults and found that < 10% of subjects return to pre-morbid levels of functioning, and the majority remain significantly impaired. The remaining studies used less stringent criteria to define their cohorts. Among patients in primary care with fatigue lasting < 6 months, at least 40% of patients improved.

As the definition becomes more stringent the prognosis appears to worsen. Consistently reported risk factors for poor prognosis are older age, more chronic illness, having a comorbid psychiatric disorder and holding a belief that the illness is due to physical causes.

Comment in:

Chronic fatigue syndrome. [QJM. 1997]

Chronic fatigue syndrome. [QJM. 1997]

 

Source: Joyce J, Hotopf M, Wessely S. The prognosis of chronic fatigue and chronic fatigue syndrome: a systematic review. QJM. 1997 Mar;90(3):223-33. http://qjmed.oxfordjournals.org/content/90/3/223.long (Full article)

 

A population-based incidence study of chronic fatigue

Abstract:

BACKGROUND: Most research on syndromes of chronic fatigue has been conducted in clinical settings and is therefore subject to selection biases. We report a population-based incidence study of chronic fatigue (CF) and chronic fatigue syndrome (CFS).

METHODS: Questionnaires assessing fatigue and emotional morbidity were sent to 695 adult men and women who had replied to a postal questionnaire survey 1 year earlier. Possible CFS cases, subjects with probable psychiatric disorder and normal controls were interviewed.

RESULTS: Baseline fatigue score, the level of emotional morbidity and a physical attribution for fatigue were risk factors for developing CF. However, after adjusting for confounding, premorbid fatigue score was the only significant predictor. A minority of CF subjects, all female, had consulted their general practitioner; higher levels of both fatigue and emotional morbidity were associated with consultation. Possible CFS cases reported similar rates of current and past psychiatric disorder to psychiatric controls, but after controlling for fatigue or a diagnosis of neurasthenia the current rates were more similar to those of normal controls. Two new cases of CFS were confirmed.

CONCLUSIONS: Both fatigue and emotional morbidity are integral components of chronic fatigue syndromes. The demographic and psychiatric associations of CFS in clinical studies are at least partly determined by selection biases. Given that triggering and perpetuating factors may differ in CFS, studies that examine the similarities and differences between chronic fatigue syndromes and psychiatric disorder should consider both the stage of the illness and the research setting.

 

Source: Lawrie SM, Manders DN, Geddes JR, Pelosi AJ. A population-based incidence study of chronic fatigue. Psychol Med. 1997 Mar;27(2):343-53. http://www.ncbi.nlm.nih.gov/pubmed/9089827

 

Lack of association of Borna disease virus and human T-cell leukemia virus type 1 infections with psychiatric disorders among Japanese patients

Abstract:

Borna disease virus (BDV) infection has been suspected to be a possible etiological factor in human psychiatric disorders and recently in chronic fatigue syndrome. Evidence of the correlation of BDV infection with these disorders remained unclear. Kagoshima is known to be one of the major areas in which human T-cell leukemia virus type 1 (HTLV-1) is endemic; this is the first isolated human retrovirus that causes adult T-cell leukemia with neurological symptoms. The present study aimed to clarify whether BDV and HTLV-1 infections are associated with psychiatric disorders among Japanese patients.

Subjects were 346 patients with psychiatric disorders (schizophrenia, 179; mood disorder, 123; and others, 44) and 70 healthy controls. Anti-BDV antibodies from plasma samples were screened by the indirect immunofluorescence (IF) method using BDV-infected MDCK cells. Results revealed that only three samples were found to be weakly positive for BDV in the IF assay and seronegative by Western blot (immunoblot) assay.

Furthermore, BDV-p24 related RNA in peripheral blood mononuclear cells from 106 of 346 psychiatric patients and 12 or 70 healthy controls by p24-reverse transcription PCR was examined. Two mood disorder patients were positive for BDV-p24 RNA but seronegative. To detect anti-HTLV-1 antibodies the plasma samples were screened by the particle agglutination method and no significant difference in seropositivity for anti-HTLV-1 antibody was found between the patients and healthy controls.

These results also suggested that there is a lack of association between BDV and HTLV-1 infections with psychiatric disorders among Japanese patients.

 

Source: Kubo K, Fujiyoshi T, Yokoyama MM, Kamei K, Richt JA, Kitze B, Herzog S, Takigawa M, Sonoda S. Lack of association of Borna disease virus and human T-cell leukemia virus type 1 infections with psychiatric disorders among Japanese patients. Clin Diagn Lab Immunol. 1997 Mar;4(2):189-94. http://www.ncbi.nlm.nih.gov/pubmed/9067654

 

Cognitive functioning is impaired in patients with chronic fatigue syndrome devoid of psychiatric disease

Abstract:

OBJECTIVE: To examine the effect of the presence or absence of psychiatric disease on cognitive functioning in chronic fatigue syndrome.

METHODS: Thirty six patients with chronic fatigue syndrome and 31 healthy controls who did not exercise regularly were studied. Subgroups within the chronic fatigue syndrome sample were formed based on the presence or absence of comorbid axis I psychiatric disorders. Patients with psychiatric disorders preceding the onset chronic fatigue syndrome were excluded. Subjects were administered a battery of standardised neuropsychological tests as well as a structured psychiatric interview.

RESULTS: Patients with chronic fatigue syndrome without psychiatric comorbidity were impaired relative to controls and patients with chronic fatigue syndrome with concurrent psychiatric disease on tests of memory, attention, and information processing.

CONCLUSION: Impaired cognition in chronic fatigue syndrome cannot be explained solely by the presence of a psychiatric condition.

 

Source: DeLuca J, Johnson SK, Ellis SP, Natelson BH. Cognitive functioning is impaired in patients with chronic fatigue syndrome devoid of psychiatric disease. J Neurol Neurosurg Psychiatry. 1997 Feb;62(2):151-5. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC486726/ (Full article)

 

Chronic fatigue syndrome. Definition, diagnostic measures and therapeutic possibilities

Abstract:

This article reviews the chronic fatigue syndrome (CFS), a disorder whose etiology is unknown. The diagnostic criteria proposed in 1994 by the CDC and the International Chronic Fatigue Syndrome Study Group are introduced.

In contrast to widespread belief, there are no laboratory tests available to underpin the diagnosis of CFS; the diagnosis is made solely on the basis of clinical criteria. In the differential diagnosis, the exclusion of other conditions that can cause chronic fatigue, such as neuropsychiatric or sleep disorders, is of critical importance.

In this context, the question as to whether CFS is a clinical entity that can be differentiated from psychiatric diagnoses, such as depression, somatoform disorder, or neurasthenia, is discussed. At the moment, there is no specific therapy for CFS. Therefore, therapeutic approaches are limited to symptomatic management of the concomitant sleep disturbances, pain, or psychiatric symptoms, such as depression.

Patients may benefit from cognitive behavioral therapy, as this may help then to identify and exclude factors contributing to and maintaining chronic fatigue. An integrated medical and psychological approach should be adopted, with the aim of preventing significant secondary negative results of the illness, such as interpersonal conflicts or chronic disability.

Comment in: “Chronic fatigue syndrome“. Nervenarzt. 1997

 

Source: Lieb K, Dammann G, Berger M, Bauer J. Chronic fatigue syndrome. Definition, diagnostic measures and therapeutic possibilities. Nervenarzt. 1996 Sep;67(9):711-20. [Article in German] http://www.ncbi.nlm.nih.gov/pubmed/8992368

 

Psychological symptoms, somatic symptoms, and psychiatric disorder in chronic fatigue and chronic fatigue syndrome: a prospective study in the primary care setting

Abstract:

OBJECTIVE: This study assessed relationships among psychological symptoms, past and current psychiatric disorder, functional impairment, somatic symptoms, chronic fatigue, and chronic fatigue syndrome.

METHOD: A prospective cohort study was followed by a nested case-control study. The subjects, aged 18-45 years, had been in primary care for either clinical viral infections or a range of other problems. Questionnaire measures of fatigue and psychological symptoms were completed by 1,985 subjects 6 months later; 214 subjects with chronic fatigue were then compared with 214 matched subjects without fatigue. Assessments were made with questionnaires, interviews, and medical records of fatigue, somatic symptoms, psychiatric disorder, and functional impairment.

RESULTS: Subjects with chronic fatigue were at greater risk than those without chronic fatigue for current psychiatric disorder assessed by standardized interview (60% versus 19%) or by questionnaire (71% versus 31%). Chronic fatigue subjects were more likely to have received psychotropic medication or experienced psychiatric disorder in the past. There was a trend for previous psychiatric disorder to be associated with comorbid rather than noncomorbid chronic fatigue. Most subjects with chronic fatigue syndrome also had current psychiatric disorder when assessed by interview (75%) or questionnaire (78%). Both the prevalence and incidence of chronic fatigue syndrome were associated with measures of previous psychiatric disorder. The number of symptoms suggested as characteristics of chronic fatigue syndrome was closely related to the total number of somatic symptoms and to measures of psychiatric disorder. Only postexertion malaise, muscle weakness, and myalgia were significantly more likely to be observed in chronic fatigue syndrome than in chronic fatigue.

CONCLUSIONS: Most subjects with chronic fatigue or chronic fatigue syndrome in primary care also meet criteria for a current psychiatric disorder. Both chronic fatigue and chronic fatigue syndrome are associated with previous psychiatric disorder, partly explained by high rates of current psychiatric disorder. The symptoms thought to represent a specific process in chronic fatigue syndrome may be related to the joint experience of somatic and psychological distress.

 

Source: Wessely S, Chalder T, Hirsch S, Wallace P, Wright D. Psychological symptoms, somatic symptoms, and psychiatric disorder in chronic fatigue and chronic fatigue syndrome: a prospective study in the primary care setting. Am J Psychiatry. 1996 Aug;153(8):1050-9. http://www.ncbi.nlm.nih.gov/pubmed/8678174