Prognostic significance of signs and symptoms in hydrocephalus. Analysis of survival.

An analysis of survival, using Cox's regression model, was performed on 231 patients with hydrocephalus diagnosed before age five years. Age range at follow-up was 21-35 years. The only constant covariate of prognostic importance was asphyxia with a factor of excess mortality of 1.70. Important time-dependent covariates were: a head circumference increasingly above the 97th percentile and/or a radiological diagnosis of hydrocephalus, general seizures, a short lapse of time since diagnosis, and the sign of downward-displaced eyes. The excess mortality of patients with the sign of downward-displaced eyes could not be expressed by a factor of excess mortality, because this was age-dependent. For the other time dependent covariates the factors of excess mortality were 2.5-6.3. Complications during pregnancy and at birth, sex, birth weight, and surgical treatment of those days were not significant for survival. Examples of survival functions with different values for the time-dependent covariates are given.