Prematurity at birth and risk of self-injury, overdose or death in adolescence and early adulthood: A population-based cohort study.

BACKGROUND

Preterm birth may adversely affect cortical brain development, and subsequent cognition in childhood and adolescence. Such abnormalities in brain development are correlated with suicidal and non-suicidal self-injury and persistent substance use, and to unintentional injury as well.

OBJECTIVE

To evaluate the risk of self-injury, overdose, and all-cause mortality among adolescents and young adults - each in relation to preterm birth.

DESIGN

Population-based cohort study in Ontario, Canada, where there is universal healthcare for all.

SETTING

All of Ontario, Canada, where there is universal healthcare.

PARTICIPANTS

All youths born in Ontario from 1992 to 2012, and alive at age 10 years.

EXPOSURES

Degree of prematurity in 2-week earlier increments, as well as preterm birth < 37 weeks' gestation.

OUTCOMES

i) Primary composite of an ED visit or hospitalization for intentional self-injury, poisoning or overdose, or all-cause mortality; and ii) co-primary composite of intentional self-injury, poisoning or overdose - each assessed between ages 10-24 years.

RESULTS

Among 2352,563 youths in the cohort, 151,182 (6.4 %) were born preterm. Adjusted hazard ratios (aHR) for i) self-injury, overdose, or all-cause mortality was 1.03 (95 % CI 1.01-1.05) per 2-week earlier gestational age at birth; and ii) 1.01 (95 % CI 0.99-1.03) for self-injury or overdose. Compared to term births, preterm birth < 37 weeks' gestation was associated with a higher aHR for i) self-injury, overdose or all-cause mortality (1.09, 95 % CI 1.05-1.12); and ii) self-injury or overdose (1.06, 95 % CI 1.02-1.10).

CONCLUSION

Preterm birth may be associated with a slightly higher risk of all-cause mortality and, possibly, self-injury and overdose among adolescents and young adults. Ongoing efforts might focus on the health of youths who were born prematurely as they enter their adolescent years.

PRIMARY FUNDING SOURCE

Canadian Institutes of Health Research.