Objective-To elucidate clinical antecedents of sensorineural hearing loss (
SNHL) in very preterm infants.
Design-Case-control study.
Subjects-Fifteen children <33 weeks' gestation with significant SNHL born b
etween 1 January 1990 and 31 December 1994, detected within 9 months of bir
th, and 30 matched control children.
Methodology-Perinatal variables in the two groups were compared using nonpa
rametric tests and conditional logistic regression (EGRET).
Results-Median birth weight for the index group was 960 g (range 600-2914 g
) compared with 1026 g (range 410-2814 g) for controls. Children with SNHL
had longer periods of intubation, ventilation, oxygen treatment, and acidos
is, and more frequent treatment with dopamine or frusemide. Neither peak no
r trough aminoglycoside levels,nor duration of jaundice or level of bilirub
in varied between groups. However, SNHL was more likely if peak bilirubin l
evels coexisted with netilmicin use (odds ratio (95% confidence interval) 1
4.2 (1.8 to 113.6)) or if acidosis occurred when bilirubin levels were over
200 mu mol/l (OR 8.0 (0.9 to 71.6). Frusemide use in the face of high seru
m creatinine levels (OR 8.9 (1.1 to 74.5)) or netilmicin treatment (OR 5.0
(0.99 to 24.8)) was also associated with SNHL. At 12 months of age, seven o
f 15 children with SNHL had evidence of cerebral palsy compared with two of
30 controls (OR 12.3 (2.1 to 71)).
Conclusions-Preterm children with SNHL required more intensive care in the
perinatal period and developed more neurological complications than control
s. Among very preterm babies, the coexistence of risk factors for hearing l
oss may be more important than the individual factors themselves.