[Epidemiological study of infantile epilepsy incidence density among infants under 36 months of age in Ningbo City from 2015 to 2019].

ABSTRACT

OBJECTIVE: To describe the distribution and trend of infantile epilepsy among infants under 36 months in Ningbo, Zhejiang Province. METHODS: Using the birth cohort design, we retrospectively collected the local born infants in Ningbo national health information platform from 2015 to 2019, and took the first visit of epilepsy in the electronic medical record of the platform as the new case. The incidence density and 95% confidence interval (CI) of epilepsy were estimated by Poisson distribution. RESULTS: From 2015 to 2019, a total of 294 900 children were born in Ningbo, with male accounting for 51.92%. The total person-years of observation were 595 300, while the median follow-up person-years was 2.31 [interquartile range (IQR) 1.90]. There were 575 new onset epilepsy patients during the whole observation period. The total number of visits was 2 599, with an average of 4.52. The total incidence density was 96.59/100 000 person-years (95%CI 88.85-104.82). The median age of onset was 13 months (IQR 15), 0-12 months old infants had the highest incidence density (102.18/100 000 person-years), 25-36 months old infants had the lowest incidence density (89.68/100 000 person-years), and the difference was not statistically significant (P>0.05). The incidence density of male was 97.58/100 000 person-years, female was 95.53/100 000 person-years, and the difference was not statistically significant (P>0.05). Fenghua was the highest (130.54/100 000 person-years, 95%CI 94.47-175.83) and Ninghai was the lowest (66.44/100 000 person-years, 95%CI 47.02-91. 19), with significant difference (P < 0.05). There was no significant difference in the incidence density in different birth years (P>0.05). There was significant difference in the incidence density between 0-12 months old infants in different calendar years (Ptrend < 0.05). In this age group, the incidence density was the lowest in 2015 (69.41/100 000 person-years, 95%CI 41.79-108.39), and the highest in 2019 (225.61/100 000 person-years, 95%CI 186.10-271.03). There was no significant difference in the incidence density between 13-24 and 25-36 months old infants in different calendar years (P>0.05). CONCLUSION: The incidence density of epilepsy in 0-36 months old infants in Ningbo City from 2015 to 2019 was low as a whole, and there was no difference in age group, gender, and year of birth. The incidence density of 0-12 months old infants increased with the year.