Genetics of Briquet's syndrome and somatization disorder. A review of family, adoption, and twin studies

Functional Neurologic Disorders, disorders to be managed by neurologists, or are neurologists wandering in a dangerous field with inadequate resources?

In recent years, some neurologists reconsidered their approach to Medically Unexplained Symptoms and proposed Functional Neurologic Disorders (FND) as a new entity, claiming that neurology could offer alternative treatment options to the psychotherapies provided in psychiatry settings. FNDs, for this purpose, should include only the disorders listed as Conversion from the Somatic Symptom and Related Disorders (SSRD) group. The present review analyzes the rationale of this position and challenges the arguments provided for its support. The review also discusses the systematization of these disorders as provided by public health systems. It outlines risks stemming from economic support and public funding uncertainty, given their negligible epidemiological dimensions resulting from the parcellation of SSRD. The review underlines the unresolved issue of Factitious Disorders, which are in the same SSRD category of the international classification but are, nonetheless, overlooked by the theoretical proponents of the FND entity. Comorbidity with other psychiatric disorders is also analyzed. We propose a model that supports the continuum between different SSRD conditions, including Factitious Disorders. The model is based on the emergence of feigned death reflex and deception from frontal lobe dysfunction. Finally, the paper summarizes the wealth of historical psychiatric and psychodynamic approaches and critical reviews. The study also puts in context the categorization and interpretation efforts provided by the most eminent researchers of the past century.

Psychobiological differences between depression and somatization

BACKGROUND

Comorbidity studies have shown that depression and somatization (multiple somatoform symptoms) often overlap. Therefore it has been suggested to classify at least some patients with somatization syndromes under the category of depressive disorders. We wanted to investigate whether psychobiological investigations confirm the lumping of somatization and depression, or whether psychobiological pathways favor distinguishing these disorders.

METHOD

An overview is presented summarizing psychobiological studies including patients with depression and/or somatization-associated syndromes. We focus on the following topics: heritability, polymorphisms in special candidate genes, immune activation, hypothalamic-pituitary-adrenal (HPA) axis reactivity, serotonergic pathways, monoamino acids, and fatty acid concentrations.

RESULTS

Immunological activation seems to be associated with specific features of somatoform disorders, namely, sickness behavior and pain thresholds. Genetic factors can also contribute to somatic complaints, e.g., via serotonergic pathways, HPA-axis response, immune activation, and other biological systems that contribute to the self-description of not being healthy. Some results indicate that psychobiological aspects of depression and somatization overlap in part (e.g., the relevance of serotonergic pathways), but there is clearly more evidence for discrepancies of psychobiological pathways in depression and somatization (e.g., the relevance of proinflammatory immune processes; HPA-axis activity; monoamino acid availability; omega-3-concentration; the role of triallelic subtypes of 5-HTTLPR).

CONCLUSION

Many psychobiological pathways act differently in depression and somatization. These differences in psychobiology favor the distinction of these syndromes in classification approaches.

Fixed belief in cognitive dysfunction despite normal neuropsychological scores: neurocognitive hypochondriasis?

A subset of patients who present for neuropsychological testing report dysfunction in daily life activities secondary to cognitive deficits, but are found on formal testing to have no objective abnormalities, raising the possibility of "neurocognitive hypochondriasis." Such a case is presented, and the factors that appear to give rise to this presentation are explored. Cases of hypochondriacal overconcern regarding cognitive function are likely not rare, particularly given research showing there is little correlation between objective report of cognitive dysfunction and actual test scores in such conditions as mild traumatic brain injury, chronic fatigue syndrome, fibromyalgia, toxic mold exposure, and post-polio syndrome.

Contrasting predictors of readiness for substance abuse treatment in adults and adolescents: a latent variable analysis of DATOS and DATOS-A participants

Although readiness for substance abuse treatment is a potent predictor of short-term clinical response, predictors of readiness are still poorly understood. Predictive models are customarily not predicated on dependence or abuse, but usually focus instead on intrapsychic motivational change or external contextual incentives. Based on a secondary analysis of the drug abuse treatment outcome studies (DATOS) data set for adults and a similar data set for adolescents (DATOS-A), latent variables were constructed to represent readiness for treatment, various psychosocial and behavioral features of substance use, substance-related problems and specific substance use frequency. Identical measures were used for each group. The two groups were then directly compared using a series of constrained covariance structure models. A path model using all hypothesized latent variables, treatment modality and demographics predicted Readiness for treatment in each separate group. Substance problems, a latent variable reflecting cross-substance symptoms of dependence and abuse, was the strongest predictor of Readiness for treatment in both age groups. Health problems and deviant family/peers were also strong predictors of readiness in both age groups. Demographic variables and specific substances used predicted readiness directly and indirectly in an age-specific manner. This study links readiness for substance abuse treatment to the core disorders targeted by that treatment in adults and adolescents for the first time.

Classification of somatization and functional somatic symptoms in primary care

OBJECTIVE

A substantial proportion of patients found in primary care complain of physical symptoms not attributable to any known conventionally defined disorder, that is, medically unexplained or functional somatic symptoms. The objective of this paper is to outline the problems with the current classification and propose a classification more suitable for primary health care.

METHOD

We refer to and discuss relevant literature including papers on our own research on the topic in the light of our experiences from major projects on somatizing patients in primary health care.

RESULTS

Functional somatic symptoms may impose severe suffering on the patient and are costly for society because of high health-care utilization, lost working years and social expenses. At present, studies on functional somatic symptoms and disorders and their treatment are hampered by lack of a valid and reliable diagnostic classification. The diagnostic categories of somatoform disorders are overlapping. Thus, the present situation is that patients with identical symptoms and clinical pictures may receive different diagnostic labels depending on the focus of interests of the assessing physician. A particular problem in primary care is that the somatoform diagnostic categories only include persistent cases and do not offer the opportunity for classification of the patients with short-symptom duration found in this setting. We present a framework for a new descriptive classification of functional somatic symptoms and unfounded illness worrying, and outline a new classification that covers the whole spectrum of severity seen in clinical practice.

CONCLUSION

A precondition for an appropriate management of patients with functional somatic symptoms is a valid taxonomy common for all medical specialties facilitating cooperative care. Classification systems as outlined in this paper may be a candidate for such a system, but it should be subject to further evaluation in research.

The relationship between irritable bowel syndrome and psychiatric illness. A family study

Although irritable bowel syndrome (IBS) is a common disorder among gastrointestinal clinic outpatients, it continues to be a diagnosis of exclusion. In treatment-seeking populations, IBS has been frequently associated with psychiatric illness, and this co-occurrence has added to controversy about the validity of the IBS diagnosis. This study is a preliminary effort to examine the nature of this relationship by using the family study design. The probands consisted of 20 patients with IBS and 20 patients who had undergone laproscopic cholecystectomy. Their first-degree relatives were interviewed to obtain lifetime diagnoses of functional gastrointestinal and psychiatric syndromes. Significantly more IBS probands had lifetime psychiatric illness than the cholecystectomy probands. The lifetime prevalence of IBS as well as other functional gastrointestinal syndromes was not significantly different between the groups of relatives. However, significantly more relatives of the IBS probands had lifetime psychiatric illness than the relatives of the cholecystectomy probands. Among the relatives with functional gastrointestinal disorders, significantly more had psychiatric illness. This preliminary study provides support for a relationship between IBS and psychiatric illness by the finding of an increased prevalence of psychiatric disorders among the relatives of patients who have IBS.