2024 American Academy of Neurology Abstract Website

Objective:

To investigate the possible benefit of cerebrospinal fluid (CSF) shunt surgery on the long-term cognitive outcomes of elderly patients diagnosed with idiopathic normal pressure hydrocephalus (iNPH).

Background:

As the proportion of the elderly within the population increases, cognitive impairments, such as iNPH, will become more burdensome on aging individuals and the American healthcare system. CSF shunt surgery is considered to be the gold-standard treatment for iNPH. Current literature suggests that advanced age is a negative predictor of cognitive recovery post-operatively. However, despite reports of cognitive recovery up to 5 years post-operatively, many existing studies lack long-term follow-up intervals. As a result, the longitudinal benefit of CSF shunting on cognitive recovery in elderly patients remains unknown.

Design/Methods:

A literature review of PubMed and the first 100 results populated by Google Scholar, sorted by relevancy, was conducted. Search parameters included "normal pressure hydrocephalus" AND shunt AND cognitive AND outcome OR neuropsych. 361 articles were returned and screened against inclusion criteria. Only original research studies were included and must have reported extractable, pre- and post-operative cognitive assessment scores of patients ≥80 years old diagnosed with iNPH. Secondary iNPH and patients with co-morbid dementia were excluded. Studies must have included a post-operative follow-up of ≥12 months. 3 articles met this criteria (total n=317) and data was extracted.

Results:

Patients ≥80 years old did not demonstrate statistically or clinically significant improvement in MMSE scores at 1, 2, 3, or 4 year follow-ups following shunt placement.

Conclusions:

The long-term cognitive benefit of CSF shunt surgery for patients ≥80 years old diagnosed with iNPH has not been demonstrated. However, existing literature in this patient demographic is limited. There remains a need for longer-term monitoring of larger patient samples using multiple cognitive assessments at standardized follow-up intervals to adequately characterize and assess post-operative cognitive recovery in iNPH.