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Birth order and pediatric traumatic brain injury
Mazin Omer1,2, Jussi P Posti3, Mika Gissler4,5,6
1Heidelberg Institute of Global Health (HIGH), University of Heidelberg, Heidelberg, Im Neuenheimer Feld 130/3, 69120, Heidelberg, Germany. mazin1255@gmail.com.
Insights
Later born children face a higher risk of pediatric traumatic brain injury (TBI) compared to firstborns. This birth order effect highlights potential factors influencing TBI risk in siblings.
Area of Science:
- Public Health
- Epidemiology
- Pediatrics
Background:
- Pediatric traumatic brain injury (TBI) is a major global public health concern.
- Limited research exists on the influence of birth order on pediatric TBI risk.
- Understanding factors affecting TBI risk is crucial for prevention strategies.
Purpose of the Study:
- To investigate the association between birth order and the risk of pediatric TBI.
- To analyze TBI incidence across different sibling positions in a large cohort.
- To identify if birth order modifies TBI risk among children.
Main Methods:
- Retrospective cohort study utilizing the 1987 Finnish Birth Cohort (FBC).
- Followed 59,469 newborns until age 18 years for first TBI diagnosis.
- Statistical analysis using hazard ratios (HR) and confidence intervals (CI), adjusted for sex and maternal age.
Main Results:
- Later born siblings demonstrated an increased risk of TBI compared to firstborns.
- Adjusted HRs for TBI risk increased with birth order: second born (1.12), third born (1.31), and fourth or higher (1.61).
- Birth order was found to significantly modify the risk for pediatric TBI within sibling groups.
Conclusions:
- Birth order is a significant factor influencing pediatric TBI risk.
- Findings suggest further research into genetic, psychological, or psychosocial factors.
- Results emphasize the need to consider sibling dynamics in TBI prevention and research.
Abstract:
Pediatric traumatic brain injury (TBI) is a significant problem of public health importance worldwide. Large population-based studies on the effect of birth order on health phenomena are exceedingly rare. This study examines the relationship between birth order and risk for pediatric TBI among sibling groups. We performed a retrospective cohort study following 59,469 Finnish newborns from 1987 until age 18 years. Data on first diagnosis of TBI was recorded within the 1987 Finnish Birth Cohort (FBC). Compared with first born siblings, later born siblings had an increased risk of TBI during the follow-up period (hazard ratio [HR] 1.02; 95% confidence interval [CI] 0.91-1.14 for second born, HR 1.09; 95% CI 0.95 1.26 for third born, HR 1.28; 95% CI 1.08-1.53 for fourth or higher). When adjusted for sex and maternal age at child's birth, HRs (95% CIs) for TBI during the follow-up period were 1.12 (0.99-1.26) for second born, 1.31 (1.12-1.53) for third born and 1.61 (1.33-1.95) for fourth born or higher children, respectively. Within this large register-based population-wide study, order of birth modified risk for pediatric TBI among sibling groups. Taken together, these study findings may serve to stimulate further inquiry into genetic, psychological, or psychosocial factors which underlie differences in risk and depth of effect within and between sibling groups.
