[Approximation to the impact of biomedical journals in neurological sciences: study of bibliometric indicators in the Journal Citation Reports-Science Citation Index 2006]

INTRODUCTION

Neurological sciences form a multidisciplinary field that produces a wide range of scientific journals. The aim of this study was to perform a scientometric analysis of neurological science journals in the 2006 Journal Citation Reports-Science Citation Index (JCR-SCI) edition.

MATERIALS AND METHODS

We study the three areas dedicated to neurological sciences (Neurosciences, Clinical Neurology and Neuroimaging) in the 2006 JCR-SCI edition. Bibliometric indicators used are: journals, articles, citations, impact factor (IF), immediacy index, half life and journals with the greatest IF in each specialty. We also perform a special analysis of Spanish neurological journals in JCR-SCI.

RESULTS

In the area of Neurosciences we find a total of 200 journals, 27.157 articles, 1.109.784 citations and an average IF of 2,446, the greatest IF belonging to Annu Rev Neurosci (28,533) and Nat Rev Neurosci (23,054); Spanish journals: Neurocirugia and Acta Esp Psiquiatr. The area of Clinical Neurology contains 147 journals, 18.114 articles, 540.364 citations and an average IF of 1,848, the greatest IF belonging to Lancet Neurol (9,479) and Ann Neurol (8,051); Spanish journals: Neurologia and Rev Neurol. The area of Neuroimaging contains 13 journals, 1.747 articles, 49.210 citations and an average IF of 1,298, the greatest IF belonging to Neuroimage (5,559) and Hum Brain Mapp (4,888).

CONCLUSIONS

We found out a broad representation of neurological journals from the 6,166 journals included in the 2006 JCR-SCI edition. Bibliometric characteristics differ in accordance to the clinical (Clinical Neurology) or experimental (Neurosciences) nature of the area. Even though bibliometric indicators for the four Spanish neurological journals have gradually improve over the previous 5 years, they are still proportionally ranked low in JCR-SCI. Due to significant limitations observed in the IF, we suggest conducting its analysis from a multidimensional bibliometric perspective, and always within its contextual research area.

[Coauthorship networks and institutional collaboration in Revista de Neurología]

INTRODUCTION

Scientific cooperation is essential for the advance of science. Bibliometrics and social network analysis offer evaluation indicators to analyse collaboration in scientific papers. The aim of this study is to characterize scientific collaboration patterns in Revista de Neurología between 2002 and 2006.

MATERIALS AND METHODS

Coauthorships and institutional relationships of papers published in Revista de Neurología have been identified. Collaboration Index, the most productive authors' and institutional collaboration patterns and the types of institutional collaborations have been quantified. Also, it has been constructed the coauthorship networks and the institutional collaboration network. Networks have been identified and represented using Access and Pajek software tools.

RESULTS

The Collaboration Index was 4.01. 56.54% of papers involved institutional collaboration. The collaboration between institutions of the same country prevails (52.7%), followed by collaborations between departments, services or units of the same institution (40.47%) and international collaboration (6.83%). 45 coauthorship networks involving 149 investigators with a high intensity of collaboration and a large institutional network involved 80 centres were observed.

CONCLUSIONS

Revista de Neurología covers scientific production of a high number of research groups. It has been observed a positive evolution in the collaboration patterns over the time. Nevertheless, it is essential to encourage inter-regional and international collaboration.

[Lumbar puncture: its indications, contraindications, complications and technique]

INTRODUCTION

Although first described over 100 years ago, lumbar puncture is still an important tool in the diagnosis of neurological diseases. In this article we review its indications, contraindications, the technique for carrying it out, the analysis of the cerebrospinal fluid and possible complications.

DEVELOPMENT

The lumbar puncture has diagnostic and therapeutic indications. The chief diagnostic indications include infectious, inflammatory and neoplastic diseases affecting the central nervous system. Complications are infrequent, except for headaches and low back pain, but can be severe. Analysis of the cerebrospinal fluid must include a cell count and determination of the glucose and protein concentrations. The other analytical studies of cerebrospinal fluid must be conducted according to the diagnostic suspicion.

CONCLUSION

The lumbar puncture in expert hands is a safe test. The health professional should be suitably familiar with its contraindications, the regional anatomy and the technique used to perform it.

[Gender analysis of papers published in Revista de Neurología (2002-2006)]

INTRODUCTION

There is an ongoing interest in the society in promoting gender equality and in women integration in research activities. The purpose of this work is to identify from a gender perspective the bibliometric characteristics of articles published in Revista de Neurología journal during the 2002-2006 period.

MATERIALS AND METHODS

Records were obtained from Science Citation Index database of ISI-Thomson platform. The following indicators were determined, disaggregated by gender: year of publication, type of document, number and order of signatures, number of collaborators, signature/papers index and in the institutional and geographical level.

RESULTS

4527 authors were identified, 2614 (57.74%) men and 1913 (42.,26%) women. The highest women's participation took place in original articles (39.01% of signatures). 44.5% of authors with one published article were women, while 'big women producers' (those with more than 9 articles) only were 16.67%. A greater productivity in men and a greater rate of collaboration in women has been detected.

CONCLUSIONS

Scientific activity studies disaggregated by gender give an essential information in order to establish the basis of a scientific policy for promoting the woman as researcher. The evolution in the number of female authors in Revista de Neurología journal does not present an aiming growth to reach the parity in the next years. A low presence of women in positions of high productivity has been detected, whose causes should be identified.

[Biomedical publications in Spain on debate (II): the on-going 'revolutions' and their application to neurological journals]

AIM AND DEVELOPMENT

To debate about the application of on-going 'revolutions' in medical knowledge to Spanish neurological journals in the 21st century. This article reviews the current status of five revolutions in the field of health sciences, in general, and in neurological sciences, in particular: 1) the knowledge revolution: to translate the scientific investigation to the patient, with knowledge needs-driven research agenda with founder commissioning research to answer questions posed by clinicians, managers and patients, and systematic and critical appraisal reviews as the creator of quality improved knowledge; 2) the evidence based medicine revolution: the pyramid information of '4S', with systems (guidelines and computerized decision support systems), synopses (secondary journals), syntheses (systematic reviews and meta-analysis) and studies (original studies published in journals); 3) the web revolution: the possibility of dissemination of biomedical documentation by means of the Internet network are producing changes in the traditional way of conceiving scientific publication; the Internet represents a great advantage for investigation and also for clinical practice, since it permits free, universal access to databases and the interchange of texts, images and videos; 4) the open access revolution: to take full control over all operations related to the process of publish (to create, publish, communicate, distribute, reproduce and transform) with no need of any intermediaries, and to transform fundamental aspects concerning the circulation of knowledge, its use and availability; and 5) the librarian revolution: the project of a Virtual Health Library in Spain as a tool to access and disseminate scientific and technical knowledge on health through the Internet.

[Biomedical publications in Spain on debate (I): state of neurological journals]

INTRODUCTION

Bibliometric studies belong to the so-called 'social studies of science', and science policy constitutes one of its main applied fields, providing objective and useful tools for evaluating the results of scientific activity. Neurological sciences are very important in the bibliometric map of Spain about biomedicine and health sciences, from a quantitative (second thematic area in productivity, only after biology-biochemical) and a qualitative (high health costs and morbimortality) point of view.

DEVELOPMENT

In Spain we can found about 360 biomedical journals, 18 of them related to the area of neurological sciences. In 2005, only 17 biomedical Spanish journals were in the Science Citation Index database, three of them in the field of neurosciences: Neurologia (impact factor = 0.57), Revista de Neurologia (0.39) and Neurocirugia (0.23), and these journals have also very good Latindex criteria about formal aspects. But it is important to mention that the impact factor specifically measures visibility and diffusion of the works published by these journals rather than their scientific quality. We search the answer to some questions about the present and future of biomedical journals in general and neurological journals in particular: paper or electronic publication?, free access or open access?, scientific journal or scientific article?, English or Spanish publication?

CONCLUSIONS

The Acuerdo de Buenos Aires is an initiative to promote scientific neurological papers of high quality in Spanish. The current status of neurological journals in the bibliometric context of our country is good and open to the advantages of electronic and free access.

[Preventive treatment with topiramate enhances the quality of life of patients with migraine]

INTRODUCTION

Topiramate has recently proved to be safe and effective in the prevention of migraine and is currently the only neuromodulatory drug indicated for the prevention of migraine in Spain.

AIM

To evaluate the adherence, effectiveness and safety of preventive treatment with topiramate in patients diagnosed with migraine.

PATIENTS AND METHODS

A prospective, observational, multi-centre study was conducted in general neurology departments. Patients eligible for the study were those with migraine, above 14 years of age, who needed preventive treatment and in whom other preventive treatments had failed or for whom topiramate was believed to be the most suitable therapy as regards its profile of side effects. The effectiveness of the treatment, patient satisfaction, side effects and loss of body weight were all evaluated. Effectiveness of the treatment was evaluated by means of the reduction in the frequency of migraines and the score obtained on the Headache Impact Test (HIT-6).

RESULTS

A total of 79 patients were evaluated. The dosage of topiramate ranged between 25 and 200 mg/day, with an average of 100 mg/day. 19% of the patients dropped out of the study due to side effects. Paresthesias were the most frequent reason for dropping out. No serious side effects were observed. 14% of the patients lost more than 5% of the base weight. The percentage of patients who responded was 58%. The degree of satisfaction of the patients who completed the follow-up was: good (80%), regular (11%) and poor (9%).

CONCLUSIONS

Preventive treatment with topiramate significantly reduces the impact of migraine and the disability that results from it. Treatment is satisfactory and improves the quality of life in a large percentage of patients.

[Generic drugs in the treatment of epilepsy]

AIM

We discuss some controversial aspects with prescription of generic drugs (GD) and the problems concerning bioequivalence, mainly in the case of drugs with non-linear pharmacokinetics and/or narrow therapeutic rank, like the antiepileptic drugs (AED).

DEVELOPMENT

There is considerable debate about GD in the treatment of epilepsy, with clearly advantages (cost saving) and disadvantages (loss of seizure control or drug toxicity) in prescribing generics anticonvulsants. We make a systematic review of the literature in primary (PubMed) and secondary (Tripdatabase and Cochrane Library) bibliographic databases in relation to GD and AED. The main information is about classical AED (phenytoin, carbamazepine, valproic acid and primidone) and we don't found studies in this area about the new AED. The level of evidence is, generally, weak, based on case-series and expert opinion without explicit critical appraisal (except in phenytoin with level of evidence moderate, based on some analytical studies). In Spain, at this moment, there are only two generic AED, one-classical (carbamazepine) and one-new (gabapentin).

CONCLUSION

The American Academy of Neurology and Epilepsy Foundation maintains that the individual and physician should be notified and give their consent before a switch in antiepileptic medications is made, whether it involves generic substitution for brand name products, or generic to generic substitutions.

[Cost effectiveness of the diagnostic study of dementia in an extra-hospital Neurology service]

AIM

The purpose of this study was to analyse the cost effectiveness of the complementary tests in the diagnosis of reversible causes of dementia in an extra-hospital Neurology service.

PATIENTS AND METHODS

Patients referred to the Neurology service from Primary Care with a diagnosis of dementia according to DSM-III-R criteria. The following routine complementary tests were performed: 1. Analyses, including blood count, biochemical study, vitamin B12 and folic levels, thyroid hormones, and syphilis serodiagnosis; 2. Neuroimaging study, consisting in computerised axial tomography or cranial magnetic resonance.

RESULTS

A total of 269 consecutive patients diagnosed as suffering from dementia were included in the study. The mean age of the patients was 74.5 years (49-94 years) and 61% were females. The most frequent cause of dementia was Alzheimer's disease (79.9%). In all, 31 patients presented potentially reversible conditions (11.5%), but if we exclude depression, the dementia was only reversible in one patient (0.4%).

CONCLUSIONS

The percentage of patients with reversible causes of dementia in the field of extra-hospital neurology is low. The diagnostic study must be individualised according to the clinical suspicion.

[A reversible posterior leukoencephalopathy syndrome]

INTRODUCTION AND METHOD

The reversible posterior leukoencephalopathy (RPLS) was initially described by Hinchey et al in patients hospitalized due to different acute process that cause hypertension and renal disease that were being treated with immunosuppressive agents. Clinically it produces an acute or subacute encephalopathy that usually agrees with a fast increase of blood pressure. Neuroimaging technique demonstrated abnormalities involving the white matter, especially bilateral edema in the posterior portions of the cerebral hemispheres, although it can also affect to any other cerebral area, trunk or cerebellum. The production mechanism is not well know. In case of hypertensive encephalopathy and eclampsia of pregnancy it is believed to be caused by vascular and endothelial autoregulation alterations, and when it's related to immunosuppressors the edema seems to have a cytotoxical origin. The particularity that defines the RPLS is that, in most cases, neurological symptoms and white matter lesions disappear after anti hypertensive treatment or when immunosuppressive agents is ceased.

CONCLUSION

The RPLS is an uncommon neurological complication, however each time more news cases appear in the medical literature. The excellent evolution and treatment response that these patients show and the full clinical and radiological recuperation suggest the need of its early identification to avoid unnecessary diagnostic studies or wrong treatments.

[Clinical and neuroimaging findings in a family with CADASIL associated to C475T mutation]

INTRODUCTION

The term CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy) refers to an autosomal dominant hereditary arteriopathy of the brain that is characterised by headache, recurring strokes and progressive cognitive deterioration. We report the case of another family with CADASIL and emphasise the importance of a genetic study in its diagnosis.

CASE REPORT

A 62-year-old female patient with repeating lacunar strokes, subcortical dementia and a family history of dementia and strokes. Neuroimaging studies conducted on the patient and her siblings showed signs of leukoencephalopathy and lacunar infarctions. The ultrastructural study of the biopsy performed on a sample of the patient's skin, which included five dermal vessels, did not show any electron-dense deposits. The genetic study revealed the presence of mutation C475T in exon 4 of NOTCH3.

CONCLUSIONS

The possible presence of CADASIL must be suspected in patients with symptoms of cerebrovascular disease or dementia who present characteristic alterations in the magnetic resonance brain scan, especially when there is a compatible family history. The first choice diagnostic procedure must be a genetic study.

Cerebral Ischemia: New Risk Factors

Stroke is a disease with well-defined modifiable risk factors such as arterial hypertension, smoking, diabetes, hyperlipidemia and atrial fibrillation. The need of new risk factors is based on the fact that only half the cardiovascular disease risk is explained by conventional risk factors. Inflammatory markers, infection, homocysteine and sleep-disordered breathing rank as the four most important new risk factors in cerebral atherosclerosis. C-reactive protein is the inflammatory marker that has been most thoroughly studied. Elevated concentrations of C-reactive protein increase the risk of heart disease and thromboembolic stroke in men and women. The role of Chlamydia pneumoniae is still controversial. Influenza vaccination is a simple and effective preventive measure against stroke. Despite the potential relationship between homocysteine and stroke, we should wait to the results of the ongoing trials to know if the reduction of homocysteine levels with vitamin therapy is of clinical benefit. Sleep-disordered breathing is a potential new risk factor with an effective therapy. Neurologists should not forget to look for sleep disorders in their stroke patients and probably manage them with breathing therapy from the acute phase.

[Paraneoplastic ataxia associated to anti CV2 antibodies]

INTRODUCTION

Anti CV2 antibodies are a type of paraneoplastic antibodies that interact with the cytoplasmatic antigens of a subpopulation of oligodendrocytes. They are usually associated with the presence of a small cell carcinoma. We report the case of a patient with an epidermoid carcinoma of the lung and paraneoplastic cerebellous ataxia associated with anti CV2 antibodies.

CASE REPORT

Male aged 73, ex smoker for 10 years, with a 45 packet/year habit. He presented a 5 month old constitutional syndrome. Altered gait with a sensation of instability. During the course of the exploration, we detected an increase in the support base, the impossibility to walk in tandem, non exhaustible horizontal nystagmus in bilateral extreme look, and vertical when looking down, with abolition of Achilles reflexes. Brain MR revealed supratentorial demyelinating lesions of a probable ischemic origin. Anti CV 2 antibodies in serum positive (anti HU negative). Biopsy performed using bronchial brushing in the left upper lobe detected the presence of malign epithelial strain, not microcytic, cells, which are compatible with epidermoid carcinoma.

DISCUSSION

Anti CV2 antibodies have only been found in patients who have developed a neurological syndrome within the context of a neoplasia. The detection of these antibodies in serum is related with the presence of a concealed neoplasia

[Descriptive epidemiology of ambulatory neurological care in the Vega Baja (Alicante) area]

AIMS

The aim of our work is to analyse ambulatory neurological care in the area of Vega Baja, which is located in the province of Alicante (Spain), in order to find out: a) the demographic characteristics of the population that visits the neurologist; b) the motives that led to the visit; c) the diagnoses carried out.

PATIENTS AND METHODS

A prospective two year study of patients over the age of 14 sent to the Neurology department. The reasons for the visit were classified into 15 categories and the diagnoses were given a code according to the criteria set out in the International Classification of Diseases 9th edition.

RESULTS

A total of 2,227 patients were included in the study. The annual incidence of first visits was 10.6 per 1,000 people. 60% of the patients were women. The average age was 51.6 years old. Headache was the most frequent reason for the visiting the doctor. One out of every three patients visited because of headache and/or facial pain. The five most frequent diagnoses in the under 65 group were, in descending order of frequency: migraine, tension type headache, epilepsy, syncope and anxiety. The five most common diagnoses in the over 65 group were, in descending order of frequency: Alzheimer, Parkinson, transitory cerebral ischemia, cerebral thrombosis and epilepsy.

CONCLUSIONS

The type of ambulatory neurological pathology depends on the age of the patients, and thus we find that headache is prevalent in the younger patients whereas neurodegenerative and vascular pathological conditions are more common in those over the age of 65.

[Amaurosis fugax as the sole manifestation of a dural arteriovenous fistula]

INTRODUCTION

Ophthalmologic disorders caused by arteriovenous malformations (AVM) are generally related with alterations in the cavernous sinus or papilloedema. However, the appearance of amaurosis fugax (AF) as the sole clinical manifestation of an AVM has very rarely been reported in the literature.

CASE REPORT

We present the case of a 64 year old male patient who displayed recurring episodes of temporary monocular blindness (AF) as a consequence of the haemodynamic disorders triggered off in the course of a dural AVM.

DISCUSSION

The arteriovenous fistula, located in the anterior fossa, gives rise to theft phenomena in the region of the arteries that nourish the retina and trigger episodes of AF of an essentially haemodynamic nature.

[Type 8 spinocerebellar ataxia. A report of a family]

INTRODUCTION

Over the past decade, from the genetic point of view, several of the entities included in the group of hereditary ataxias have been identified. We report a Spanish family with type 8 spinocerebellar ataxia (SCA8), one of the most recent hereditary ataxias to be described from the clinical and genetic points of view.

CLINICAL CASE

A 59 year old woman consulted us complaining of progressive dysarthria and unsteady gait. The only abnormal findings on neurological examination were those of cerebellar involvement. The patient s mother had a similar condition, characterized by difficulty in speaking which started when she was 62 years old and progressed to anarthria. Cranial magnetic resonance showed the presence of cerebellar atrophy with no signs of atrophy of the brainstem. On electromyographic studies there were no signs of neuropathy. Visual, auditory and sensory evoked potentials were normal. Genetic studies showed expansion of trinucleotide CTG (112 repetitions in the expanded allele and 28 repetitions in the normal allele) on the gene responsible for SCA8.

CONCLUSION

SCA8 should be included in the differential diagnosis of progressive cerebellar syndromes, especially when changes in speech predominate with regard to other cerebellar signs.

[Validation of a model for the prediction of verbal semantic fluency]

INTRODUCTION

The diagnosis of dementia requires documentation of cognitive loss with respect to the patient's previous level. It would therefore be very useful to have models available which would predict the result expected in the tests normally used in the diagnosis of dementia.

OBJECTIVE

To validate a model for prediction of the results of a test of semantic verbal fluency in persons with no dementia.

PATIENTS AND METHODS

A model for the prediction of semantic verbal fluency deduced from a sample of 138 persons was applied to two other independent samples: the first of 86 persons from the same environment as the original sample and a second multicentric sample of 92 persons. The validity of the model was evaluated by residual analysis.

RESULTS

No sex differences were seen between the samples, but there were differences regarding the other variables, including the observed and predicted verbal fluency. The residuals of the samples did not differ from each other nor vary from zero, but were normally distributed.

CONCLUSION

The model proposed based on sociodemographic and clinical variables is valid and satisfactorily predicts the verbal fluency to be expected in each case.

[Side effects of antithrombotic treatment in the secondary prevention of cerebrovascular disease]

OBJECTIVE

To determine the incidence of adverse effects of antithrombotic drugs (platelet anti-aggregants and anticoagulants) in patients with transient ischemic attacks (TIA) and mild ischemic strokes (IL).

PATIENTS AND METHODS

Clinical follow-up data on the patients with TIA and IL included in a community-based observational study undertaken in the province of Segovia. Adverse effects which led to suspension of treatment or were a potential danger for the patient's life were recorded.

RESULTS

The groups studied included 235 patients and the average initial age was 70.8 years. The average follow-up time was 3.6 years. The treatment initially given included: aspirin (75.7%), ticlopidine (12.8%) and acenocumarol (9.4%). Adverse effects led to suspension of treatment in 6% (5% with aspirin and acenocumarol, 17% with ticlopidine). The adverse effects of ticlopidine were mild and patients did not need admission to hospital (cutaneous exanthema, diarrhoea and reversible leucopenia). Aspirin was associated with digestive tract bleeding (2.8%) and cerebral hemorrhage (1.7%) which required hospital admission in most cases. One patient treated with acenocumarol presented with a retroperitoneal hematoma.

CONCLUSIONS

In general antithrombotic drugs are well-tolerated by patients with TIA and LI. Hemorrhagic complications, particularly of the digestive tract, associated with aspirin limit tolerance to it.