Prevalence and Trends in Management of Idiopathic Normal Pressure Hydrocephalus in the United States: Insights from the National Inpatient Sample

Mohammed Ali Alvi, Desmond Brown, Yagiz Yolcu, Jad Zreik, Saad Javeed, Mohamad Bydon, Jeremy K. Cutsforth-Gregory, Jonathan Graff-Radford, David T. Jones, Neill R. Graff-Radford, Petrice M. Cogswell, Benjamin D. Elder

Research output: Contribution to journalArticlepeer-review


Background: Over the past 2 decades, management of idiopathic normal pressure hydrocephalus (iNPH) has evolved significantly. In the current study, we sought to evaluate the national prevalence and management trends of iNPH in the United States using a national database. Methods: The National Inpatient Sample was queried for patients with an International Classification of Diseases diagnosis code for iNPH from 2007 to 2017. Trends in prevalence and procedure type were evaluated per 100,000 discharges and as a percentage of discharges, using weighted discharges. Utilization of procedure type across U.S. regions and hospital types was also compared. Results: From 2007 to 2017, 302,460 weighted discharges with any diagnosis code for iNPH, aged ≥60 years, were identified. Prevalence ranged from 0.04% to 0.20% (41/100,000 to 202/100,000) among admitted patients ≥60 years old, giving an average prevalence during the study duration of 0.18% (179/100,000). Of 66,759 weighted discharges with a primary diagnosis code of iNPH undergoing surgical management, ventriculoperitoneal shunt (72.0% of discharges, n = 48,977) was most commonly used; of these, 9.3% (n = 4567) were performed laparoscopically. This result was followed by lumbar peritoneal shunt (15.1% of discharges, n = 10,441). Up to 15.1% (n = 9990) of discharges reported only a lumbar puncture, assumed to be only diagnostic, for screening, or part of serial cerebrospinal fluid removal procedures. Significant discrepancies in procedure utilization were also identified among hospitals in the Western, Southern, Northeast and Midwest regions, as well as between urban and rural hospitals (P < 0.05). Conclusions: We have summarized the national prevalence of iNPH, trends in its management over the previous decade and trends by region and hospital type.

Original languageEnglish (US)
Pages (from-to)e38-e52
JournalWorld neurosurgery
StatePublished - Jan 2021


  • Hydrocephalus
  • Idiopathic normal pressure hydrocephalus
  • NIS
  • NPH
  • Normal pressure hydrocephalus
  • Shunt
  • iNPH

ASJC Scopus subject areas

  • Surgery
  • Clinical Neurology


Dive into the research topics of 'Prevalence and Trends in Management of Idiopathic Normal Pressure Hydrocephalus in the United States: Insights from the National Inpatient Sample'. Together they form a unique fingerprint.

Cite this