# Presentation: 143729

## Support for Creation of an ICD-9 Code for Normal Pressure Hydrocephalus (NPH)

- Michael A. Williams, M.D.
- Adult Hydrocephalus Program
- Departments of Neurology and Neurosurgery
- Johns Hopkins Hospital
- Baltimore, MD

**Notes:**
Today we would like to review with you some of our concepts in Hydrocephalus hoping to be able to distinguish at the end between facts and myths.

## Disclosure

- In the last 12 months:
- Our program received research support from Medtronic
- I have received honoraria from Medtronic
- I am on Codman’s NPH Advisory Panel
- The content of this presentation is intended to be independent and free from commercial bias.
- My affiliations are shown for the purpose of identification.  I am not representing the views of the Johns Hopkins Medical Institutions.

- Support for ICD-9 Code for NPH

- M.A. Williams

## A resource for patients and families

- _[www.hydroassoc.org](http://www.hydroassoc.org/)__888-598-3789_**Biannual Meeting**
**May 26-29, 2006**
**Hyatt Regency Hotel**
**Baltimore, MD**
- Disclosure:  I serve on their Medical Advisory Board as a volunteer

- Support for ICD-9 Code for NPH

- M.A. Williams

## Definition and ICD-9 Coding of  Adult Hydrocephalus 

- Ventricular enlargement due to altered CSF flow or resorption, with or without symptoms or neurologic impairment
- Obstructive Hydrocephalus (331.4)
- Impairment of CSF flow within the ventricular system
- Communicating Hydrocephalus (331.3)
- Impairment of CSF flow or resorption outside the ventricular system
- Impaired flow through the subarachnoid space
- Impaired resorption at the arachnoid granulations

- Support for ICD-9 Code for NPH

- M.A. Williams

**Notes:**
To keep the concept simple, let’s say that Hydrocephalus is characterized by ventricular dilatation due to altered CSF flow.

## Obstructive Hydrocephalus:Aqueductal Stenosis (331.4)

- 36-yo man with headaches,syncope, job impairment

- Support for ICD-9 Code for NPH

- M.A. Williams

**Notes:**
Please note the unusual elevation of the quadrigeminal plate in this case of distal aqueductal stenosis.
Also note the extreme callosal distension.
Note borderline Chiari.
Presentation with syncope.

## Communicating Hydrocephalus (331.3)

- Idiopathic
- In the elderly, normal pressure hydrocephalus
- Chronic, insidious onset
- Symptomatic (secondary) hydrocephalus
- Post-subarachnoid hemorrhage (aneurysm), post-infectious, post-traumatic
- Acute, subacute or chronic onset

- Support for ICD-9 Code for NPH

- M.A. Williams

## Normal Pressure Hydrocephalus

- NPH is a treatable form of dementia, gait apraxia and urinary incontinence
- Treatment is surgical--shunt insertion
- Treatable nature of NPH distinguishes it from the essentially untreatable nature of most dementias
- Common diagnostic tests do not predict the outcome from shunt surgery very well

- Support for ICD-9 Code for NPH

- M.A. Williams

## NPH Diagnosis

- NPH clinically overlaps with many conditions of the elderly
- Vascular dementia
- Degenerative dementias or disease
- Cervical stenosis/myelopathy
- Lumbar stenosis
- Peripheral neuropathy

- Support for ICD-9 Code for NPH

- M.A. Williams

## Consensus Guidelines

- Supplement to Neurosurgery September 2005
- Important contribution to the literature
- Identifies existing knowledge and gives good, practical advice
- Identifies significant gaps in our knowledge

- Support for ICD-9 Code for NPH

- M.A. Williams

## INPH Guidelines Diagnostic AlgorithmNeurosurgery 2005:57:S2-17-S2-28

- INPH Guidelines Diagnostic AlgorithmNeurosurgery 2005:57:S2-17-S2-28

- Support for ICD-9 Code for NPH

- M.A. Williams

## Treatment results in meaningful improvement in NPH

- Gait and incontinence improve
- As shown by MCV and Hopkins studies
- Dementia improves
- While some debate in the literature
- We have published 3 papers showing significant overall cognitive improvement
- Defined as a 4-point improvement in MMSE, or improvement by 1 SD in 50% of the administered neurocognitive subtests, compared to the baseline

- Support for ICD-9 Code for NPH

- M.A. Williams

## NPH Cognitive Improvement Surpasses AD Improvement

- “Our finding of over 50% of INPH patients with significant overall cognitive improvement 3 months after shunt insertion may be an underestimation, as long-term improvement at 6–12 months has been reported in more than 60% of INPH patients. On the other hand, drug trials in AD patients with acetylcholinesterase inhibitors did not demonstrate a significant difference between baseline and 3- to 6-month posttreatment scores, and less than half the patients achieved a clinically significant response.”
**Dement Geriatr Cogn Disord 2005;20:163–168**

- Support for ICD-9 Code for NPH

- M.A. Williams

## Outcome of 132 Pts with Idiopathic NPH

- McGirt MJ, Coon AL, Thomas G, Woodworth G, Williams MA, Rigamonti D.  Diagnosis, treatment and analysis of long-term outcomes in idiopathic normal pressure hydrocephalus.  Neurosurgery 2005;57:699-705.

- Support for ICD-9 Code for NPH

- M.A. Williams

## The problem with 331.3

- There is a wide spectrum of clinical presentation for “communicating hydrocephalus” coded as 331.3
- It includes critically ill patients in the ICU with hydrocephalus from subarachnoid hemorrhage, for example, as well as patients with NPH

- Support for ICD-9 Code for NPH

- M.A. Williams

## Post SAHEarly Hydrocephalus (331.3)

- Support for ICD-9 Code for NPH

- M.A. Williams

## Post SAH Delayed Hydrocephalus (331.3)

- Support for ICD-9 Code for NPH

- M.A. Williams

## So why is that a problem?

- Our ability to use databases dependent on ICD-9 codes to understand many different aspects and outcomes of a clinically distinct, treatable form of hydrocephalus is impaired
- We used the Medicare SAF to investigate costs of diagnosing and treating NPH

- Support for ICD-9 Code for NPH

- M.A. Williams

## Health Care Expenditures in 331.3Methods

- Retrospective cost analysis using the Standard Analytic Files of paid claims for beneficiaries enrolled in both Parts A and B Medicare for 1997 through 2001 (Index year 1999).
- A 5% sample of the SAF yielded a total of 1441 beneficiaries with a diagnosis code 331.3, including 362 (25.1%) who received a first shunt and 1079 who did not.

- Support for ICD-9 Code for NPH

- M.A. Williams

## Health Care Expenditures in 331.3Results

- The effect of a shunt procedure on 5-year Medicare expenditures is a cost reduction of $25,477 (p<.0001) per patient
- Potential $184.3 million reduction in 5-year Medicare expenditures
- After factoring in shunt complications (17.4% of pts) there was still a $157 million reduction in 5-year Medicare expenditures

- Support for ICD-9 Code for NPH

- M.A. Williams

## BUT

- We cannot identify how many of these patients had NPH and how many had other forms of 331.3
- What about the 75% of 331.3 who were never treated?
- In light of the aging population, the number of pts with NPH will rise, and so will health care expenditures if they are not identified or treated
- A unique ICD-9 code for NPH will enable us to follow the epidemiology, outcomes, and financial impact of this important disorder

- Support for ICD-9 Code for NPH

- M.A. Williams

## Summary

- Normal pressure hydrocephalus is a distinct clinical entity, and patients have significant improvement with treatment
- A new ICD-9 code, 331.5, will benefit patients and the population by improving diagnostic accuracy
- On behalf of myself and the Medical Advisory Board of the Hydrocephalus Association, I support the creation of 331.5 for NPH

- Support for ICD-9 Code for NPH

- M.A. Williams

## Normal Pressure Hydrocephalus

- Support for ICD-9 Code for NPH

- M.A. Williams

## Thank you