Table 3.

Incidence rate and hazard ratios for epilepsy risk factors among 129 children with neonatal encephalopathy.

	Person- years	Epilepsy cases	Incidence rate/1000 person-years (95% CI)	HR (95% CI)	P
Perinatal Characteristics
Sex
- Females	381	5	13.1 (5.5 – 31.6)	-
- Males	444	8	18.0 (9.0 – 36.1)	1.3 (0.4–4.1)	0.6
Delivery Method
- Vaginal delivery	468	9	19.2 (10.0 – 37.0)	-
- Cesarean section	356	4	11.2 (4.2 – 29.9)	0.5 (0.2–1.6)	0.2
5 minute Apgar score
≥6, N(%)	305	2	6.6 (1.6 – 26.2)	-
4–5, N(%)	280	6	21.5 (9.6 – 47.8)	2.8 (0.6 – 18.8)
0–3, N(%)	238	5	21.0 (8.7 – 50.5)	2.5 (0.5 – 12.8)	0.4
Degree of encephalopathy (N = 100)*
Moderate	305	1	3.3 (0.5 – 23.2)	-
Severe	267	12	45.0 (25.5 – 79.2)	10.7 (1.4 – 82.7)	0.002
Therapeutic Hypothermia
Not treated	774	11	14.2 (7.9 – 25.7)
Treated	51	2	39.4 (9.9 – 157.6)	0.9 (0.2 – 4.1)	0.8
Neonatal seizures (N=53)**
Clinical only	206	3	14.6 (4.7 – 45.1)	-
EEG confirmed seizures	53	5	93.5 (38.9 – 224.7)	4.0 (0.9 – 17.3)
Status epilepticus	4	5	1237.1 (514.9 – 2972.2)	35.8 (6.5 – 196.5)	0.0001
MRI injury (N = 87)§
Mild/moderate	434	5	11.5 (4.8 – 27.7)	-
Severe/near-total	146	8	54.7 (27.4 – 109.4)	5.5 (1.8 – 16.8)	0.003

^*No cases of epilepsy among children with mild neonatal encephalopathy;

^**No cases of epilepsy among children without neonatal seizures;

^§No cases of epilepsy among children without injury on neonatal MRI.