Seasonal birth patterns of neurological disorders

Existing seasonal birth studies were reviewed for multiple sclerosis (MS), Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis (ALS), epilepsy, cerebral palsy, congenital malformations of the central nervous system and mental retardation. Epilepsy appears to have the most consistent pattern, with an excess of births in winter and a deficit in September. MS, ALS and possibly Parkinson's disease appear to have an excess of spring births. Studies of cerebral palsy are not conclusive, although there are suggestions that there may be an excess of summer births. The findings for Alzheimer's disease, congenital malformations of the central nervous system, and mental retardation are contradictory and insufficient to draw any conclusions.     

The future of genetic analysis of neurological disorders

Molecular genetic analysis has allowed the elucidation of the etiology of many single-gene, neurodegenerative syndromes. However, as yet, it has had little direct impact on our understanding of the etiology in cases with more complex modes of inheritance. With the completion of the sequence of the human genome, it should be possible to start to attack these more complex problems. In this article, we review the genetic methods that may be used to dissect the etiologies of these diseases and outline what types of clinical samples will be needed for this quest.     

Controversies in neurological infectious diseases

The past several years have seen major advances in our understanding of neurological infectious diseases, their diagnosis, and their treatment. Along with these advances, however, new information about infectious agents and new therapeutic options have also introduced both uncertainty and controversy in the approach and management of patients with diseases of the central nervous system. Here, we discuss six such areas: the long-term efficacy of HAART therapy in treatment of HIV infection; the role of viral infection in chronic fatigue syndrome; Rasmussen's encephalitis as an infectious or autoimmune disease; the spectrum of neurological diseases caused by rickettsial infection; the role of Mycoplasma pneumoniae in human central nervous system disease; and the possible association of Chlamydia pneumoniae and human herpesvirus 6 with multiple sclerosis.     

Acanthocytosis and neurological disorders

Acanthocytosis occurs because of ultrastructural abnormalities of the erythrocyte membranous skeleton resulting in reduced membrane fluidity. At least three hereditary neurological conditions are associated with it, although as yet the pathogenesis of the neurological features is unknown. In abetalipoproteinaemia, an autosomal recessive condition, vitamin E deficiency results in a progressive spinocerebellar syndrome associated with peripheral neuropathy and retinitis pigmentosa. Neuroacanthocytosis is also probably an autosomal recessive condition and is characterised by chorea, orofaciolingual dyskinesia, dysarthria, areflexia, seizures and dementia. McLeod syndrome is an X-linked recessive disorder usually presneting in males as a benign myopathy within areflexia, in association with a particular abnormality of expression of Kell blood group antigens. However, occasionally the neurological features are more severe and indistinguishable from those of neuroacanthocytosis. Recent advances in molecular genetics may assist better understanding of the disease mechanisms and the search for more effective treatment. Received: 19 June 2000 / Accepted: 28 July 2000     

Depression and neurological disorders

Depression is the most common psychiatric disorder in neurological disorders such as epilepsy, multiple sclerosis, stroke, and Parkinsons disease. It is associated with reduction of quality of life, functional impairment, and higher mortality. The diagnosis of depression in neurological disorders is difficult because of the overlapping symptoms. Neurological disorders are usually associated with sleep and appetite disturbances, fatigue, apathy, and lack of concentration, which is similar to those of depression. The etiology of depression with neurological disorders is unknown, but the interaction between biological, psychosocial, and neuropathological factors could be responsible for it. Few controlled trials have been carried out to investigate the efficacy of psychotherapeutic and pharmacological interventions in this population, and it seems that they are effective in improving depression, quality of life, and survival. Studies pertaining to prevention of depression in neurological disorders are promising.     

Depression and neurological disorders

PURPOSE OF REVIEW: Clinical studies support a bidirectional link between depression and neurological diseases. Here we review the most recent findings supporting the hypothesis that major depression is a medical illness of the brain which can be elicited by neurological illnesses. RECENT FINDINGS: In the last year major improvements in brain-imaging techniques allowed correlations to be demonstrated between functional and structural brain abnormalities in specific brain areas (prefrontal cortex, hippocampus, cingulate gyrus) and the presence and severity of affective disorders, thus suggesting a neural basis for their onset and progression. Similar lesions, caused by neurological diseases, have been found to correlate with the presence of depression in neurological illnesses, but literature on the topic is still lacking. Depression in neurological disorders responds to the same treatments available for idiopathic major depression, but patients seem to have different sensitivities to side effects depending on their specific neurological syndrome. Most available data come from case reports and open trials. SUMMARY: 'Psychiatric' and 'neurologic' depression seem to share common abnormalities in specific brain areas, but sound brain-imaging studies of the neural correlates of depression in neurological disorders are still lacking. Available treatments are efficacious, but no clear-cut guidelines about the best drugs and dosages can be defined because double-blind placebo-controlled studies are still scarce.     

Scoring alternatives for FIM in neurological disorders applying Rasch analysis

OBJECTIVE: The Functional Independence Measure (FIM) is an internationally widely used outcome measure. The aim of this study was to evaluate the structural properties of FIM using the Rasch model, with regard to scoring within rehabilitation centres in Scandinavia. MATERIALS AND METHODS: FIM data from 1660 patients with stroke, traumatic brain injury and spinal cord injury were analysed. The best models with respect to person separation were determined, together with person reliability, item separation, disordered categories, distance of more than 1.4 logits between categories and item fit to the model. RESULTS: Analysis showed disordering using seven categories in all three diagnoses. After collapsing of categories a four-category scale was the best solution. CONCLUSIONS: Decreasing the categories from seven to four may be one way of dealing with problems of disordered thresholds. Further studies are also needed in order to try the suggested scale in clinical settings and to compare it with the original FIM scale.     

Somatoform disorders in neurological practice

PURPOSE OF REVIEW: Patients with medically unexplained symptoms continue to intrigue, fascinate and frustrate clinicians. They are common in general medicine and often present with apparent neurological disorder. This review aims to provide insight into the recent literature that has sought to clarify epidemiology, diagnostic issues, aetiologic understanding and treatment of patients with psychogenic disorders who usually first present to neurologists. RECENT FINDINGS: Somatoform disorders are common in neurological practice. A number of papers have addressed issues of epidemiology and identified that medically unexplained symptoms in neurological populations are higher than originally thought. A number of recent review papers have served to summarize areas of considerable information (e.g. treatments) and areas of rapid growth in knowledge (e.g. neuroimaging). Studies investigating the role of psychological factors are well represented and clarify our psychopathological understanding of somatoform disorders in patients presenting to neurologists. Treatment studies are few and continue to be limited by population sizes and study designs. SUMMARY: Somatoform disorders are common in neurological populations. Comorbidity related to somatoform disorders with known organic neurological conditions requires further study. On account of the limitations of treatment studies, evidence-based clinical management of these patients is awaited.     

Depressive syndromes in neurological disorders

Depressive syndromes represent a common and often characteristic feature in a number of neurological disorders. One prominent example is the development of post-stroke depression, which can be observed in more than one-third of stroke survivors in the aftermath of an ischemic stroke. Thus, post-stroke depression represents one of the most prevalent, disabling, and potentially devastating psychiatric post-stroke complications. On the other hand, depressive syndromes may also be considered as a risk factor for certain neurological disorders, as recently revealed by a meta-analysis of prospective cohort studies, which demonstrated an increased risk for ischemic events in depressed patients. Moreover, depressive syndromes represent common comorbidities in a number of other neurological disorders such as Parkinson’s disease, multiple sclerosis, or epilepsy, in which depression has a strong impact on both quality of life and outcome of the primary neurological disorder.

     

Perivascular space and neurological disorders

Perivascular space (PVS) is a crevice between two slices of cerebral pia maters, filled with tissue fluid, which be formed by pia mater emboling in the surrounding of cerebral perforating branch (excluding micrangium). Normal PVS (diameter < 2 mm) can be found in almost all healthy adults; however enlarged PVS (diameter > 2 mm) has correlation with neurological disorders probably. The article reviews the formation mechanism, imageology characteristics and the relation with neurological disorders of PVS, which is beneficial to the research of some neurological disorders etiopathogenesis and treatment.