• Rubén Martín-Láez, Hugo Caballero-Arzapalo, Natalia Valle-San Román, Luis Ángel López-Menéndez, Juan Carlos Arango-Lasprilla, and Alfonso Vázquez-Barquero.
• Department of Neurosurgery-Spine Unit, University Hospital "Marqués de Valdecilla", Santander, Spain. Electronic address: rmlaez@yahoo.es.
• World Neurosurg. 2016 Mar 1; 87: 298-310.

BackgroundAlthough 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.MethodsIn 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.ResultsFrom 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).ConclusionsEven with a protocol for patient referral in place, reported iNPH incidence was lower than predicted, reflecting a persistent problem of underdiagnosis in our population.Copyright © 2016 Elsevier Inc. All rights reserved.

34 keywords...

hide…