Prognosis regarding shunt revision and mortality among hydrocephalus patients below the age of 2 years and the association to patient-related risk factors

Little is known about the prognosis regarding shunt revision and mortality among hydrocephalus patients below 2 years of age. The aims of this study were to investigate (1) the cumulative risks of shunt revision (SR) and mortality and (2) the potential associations between prematurity, low weight for gestational age (LWGA), underlying aetiology, sex, age of the child at shunt placement, and the risk of SR. This was a purely register-based cohort study including all shunted hydrocephalic infants in Denmark 1996–2015. The cumulative risks of SR and mortality were estimated using the Aalen-Johansen and Kaplan-Meier estimators, respectively. A multivariable Cox-regression model was used to estimate hazard ratios (HRs) for SR according to the listed patient-related risk factors. Among 374 shunted infantile hydrocephalus patients accounting for 1047 SRs, the 3-month and 1-year cumulative risks of SR were 36% and 50%, respectively. The overall 10-year cumulative mortality was 12%, and for non-tumour subgroups 7–16% (isolated hydrocephalus 7%). The 10-year cumulative mortality for children born with LWGA was 21%. Except for aetiology, we observed no strong overall associations between the investigated risk factors and the risk of SR but interaction analyses for aetiology showed that patients with Dandy-Walker malformation born with LWGA had a higher risk of SR compared to patients of similar aetiology with normal WGA (HR 2.47, 95% CI: 1.39–4.40). We found very high cumulative risks of SR and mortality among this youngest group of hydrocephalus patients, disregarding aetiology, but none of them were strongly related to the investigated risk factors.