Rubén Martín-Láez

Epidemiology of Idiopathic Normal Pressure Hydrocephalus: A Systematic Review of the Literature.

BACKGROUND Idiopathic normal pressure hydrocephalus (iNPH) is an important cause of gait disturbance and cognitive impairment in elderly adults. However, the epidemiology of iNPH is relatively unknown, largely as a result of the paucity of specifically designed population studies. This systematic review aims to assess the prevalence and incidence of iNPH. METHODS A systematic literature review on the epidemiology of iNPH was conducted using MEDLINE/PubMed searching for articles published up to June 2014. RESULTS The inclusion criteria were met by 21 studies. Of the studies, 12 were specifically designed for detecting cases of iNPH; however, only 4 were prospective. In people >65 years old, pooled prevalence obtained from specific population studies was 1.3%, which was almost 50-fold higher than that inferred from door-to-door surveys of dementia or parkinsonism. Prevalence may be higher in assisted-living and extended-care residents, with 11.6% of patients fulfilling the criteria for suspected iNPH and 2.0% of patients showing permanent improvement after cerebrospinal fluid diversion. The only prospective population-based survey that reported iNPH incidence estimated 1.20 cases/1000 inhabitants/year, 15-fold higher than estimates obtained from studies based on hospital catchment areas. The incidence of shunt surgery for iNPH and shunt-responsive iNPH obtained from incident cases of hospital catchment areas appears to be <2 cases/100,000 inhabitants/year and 1 case/100,000 inhabitants/year, respectively. No population-based study reporting the real values for these 2 parameters could be found. CONCLUSIONS iNPH appears to be extremely underdiagnosed. Properly designed and adequately powered population-based studies are required to characterize the epidemiology of this disease accurately.

Incidence of Idiopathic Normal-Pressure Hydrocephalus in Northern Spain

BACKGROUND Although the incidence of idiopathic normal-pressure hydrocephalus (iNPH) can be 1.20 cases/1000 inhabitants/year in individuals ≥ 70 years old, in most series, the incidence of shunt-responsive iNPH appears to be <1/100,000 inhabitants/year. We report the results of a prospective 10-year longitudinal study of the incidence of iNPH in a northern Spanish population. METHODS In a stable population of 590,000 inhabitants served by a single neurosurgical department, we periodically asked all primary care practitioners, neurologists, and geriatricians to refer for iNPH screening any patient with ventricular dilation who was complaining of motor disturbances, cognitive impairment, or sphincter dysfunction. RESULTS From January 2003 to December 2012, 293 patients were referred with suspected normal-pressure hydrocephalus. In 187 patients, iNPH was diagnosed; 89 of these patients were classified as probable iNPH, and 98 were classified as possible iNPH. Cerebrospinal fluid diversion was performed in 152 patients, and 119 showed a good outcome. The incidence of iNPH was significantly greater in male patients and patients >60 years old and increased exponentially with age. After age 60, the standardized age- and sex-adjusted incidence rates for iNPH, shunt surgery for iNPH, and shunt-responsive iNPH were 13.36 cases/100,000 inhabitants/year, 10.85 cases/100,000 inhabitants/year, and 8.55 cases/100,000 inhabitants/year. No differences were detected in the response rate between probable and possible iNPH (80.52% vs. 76.00%; P = 0.497). CONCLUSIONS Even with a protocol for patient referral in place, reported iNPH incidence was lower than predicted, reflecting a persistent problem of underdiagnosis in our population.

Pronóstico a largo plazo de la hidrocefalia crónica del adulto idiopática: I. Protocolo diagnóstico-terapéutico del Hospital Universitario Marqués de Valdecilla

INTRODUCTION Despite the existence of published guidelines for more than a decade, there is still a substantial variation in the management of idiopathic normal pressure hydrocephalus due to its diagnostic and therapeutic complexity. DEVELOPMENT The diagnostic and therapeutic protocol for the management of idiopathic normal pressure hydrocephalus in use at the Department of Neurosurgery of the University Hospital Marqués de Valdecilla is presented. The diagnostic process includes neuropsychological testing, phase contrast cine MRI, urodynamic evaluation, continuous intracranial pressure monitoring, cerebrospinal fluid hydrodynamics by means of lumbar infusion testing, and intra-abdominal pressure measurement. A patient is considered a surgical candidate if any of the following criteria is met: mean intracranial pressure >15mmHg, or B-waves present in >10% of overnight recording; pressure-volume index <15ml, or resistance to cerebrospinal fluid outflow (ROUT) >4.5mmHg/ml/min in bolus infusion test; ROUT >12mmHg/ml/min, intracranial pressure >22mmHg, or high amplitude B-waves in the steady-state of the continuous rate infusion test; or a clinical response to high-volume cerebrospinal fluid withdrawal. CONCLUSIONS The implementation of a diagnostic and therapeutic protocol for idiopathic normal pressure hydrocephalus management could improve various aspects of patient care. It could reduce variability in clinical practice, optimise the use of health resources, and help in identifying scientific uncertainty areas, in order to direct research efforts in a more appropriate way.

¿Era el actual superávit de neurocirujanos previsible en 2009? Análisis de la situación sobre la base de los datos del Informe de oferta y necesidad de especialistas médicos en España (2008-2025)

INTRODUCTION In 2009 the Spanish Ministry of Health (SMH) published the report of supply and demand of medical specialists in Spain (2008-2025), in which our specialty was considered as presenting a moderate deficit of consultants. However, Spanish neurosurgery is currently in a situation of having a surplus of neurosurgeons. OBJECTIVES To determine whether it was possible to predict the current excess of neurosurgeons in 2009 and to forecast the most likely perspective of supply and demand in 2017. MATERIAL AND METHODS Raw data extracted from the SMH report, information on the ages of the Spanish neurosurgeons obtained from the study performed by our Board of Directors in 2001, and annual mortality rates for different age ranges provided by the National Institute of Statistics, were used to predict the evolution of supply and demand of neurosurgeons for the periods 2008-2012 and 2013-2017. RESULTS The current situation of an excess of specialists was predictable in 2009, and if appropriate measures are not taken, a surplus of more than 100 neurosurgeons is likely in 2017, with an unemployment rate above 26% in the worst scenario. CONCLUSIONS In order to match the actual and future demand of specialists, it is necessary and urgent to reduce the number of neurosurgical in-training positions. To achieve this goal, it is essential to obtain periodical and up-to-date structural information of the different Neurosurgery Departments and Units, and to revisit the accreditation terms of the more than fifty current teaching units.