Demographic factors influence cognitive recovery after shunt for normal-pressure hydrocephalus

Background: Several studies have reported that ventriculoperitoneal shunt insertion for treatment of normal-pressure hydrocephalus results in improvement of gait and, less frequently, improvement of cognition. We sought to identify the demographic factors associated with cognitive improvement after shunt insertion to improve assessment of prognosis for cognitive gains with treatment. Review Summary: We report cognitive testing before and after ventriculoperitoneal shunt insertion in 36 patients with normal pressure hydrocephalus, who previously had improvement of any clinical symptom - gait, urinary incontinence, cognition - after a diagnostic trial of continuous cerebrospinal fluid drainage. Conclusions: One third of patients met our definition of good cognitive improvement: improvement by at least 25% on at least half of the cognitive tests administered. There was a significant negative linear relationship between age and probability of good cognitive improvement. Additionally, the degree of cognitive improvement was found to be greater in women than men (P = 0.002). Age was found to be a better predictor of improvement on memory tests, while sex was a better predictor of improvement on non-memory tests after shunt insertion.