A new study published in PLoS Medicine reports that children born severely small for gestational age (SGA) have an increased risk of death throughout childhood, up to age 18 years.
The Swedish study compared mortality among SGA children to non-SGA children from the population and to non-SGA siblings.
Crude mortality rate per 10,000 person-years was 5.32 in children with severe SGA, 2.76 in children with moderate SGA, and 1.93 in non-SGA children.
Compared with non-SGA children, children born severely SGA had an increased risk of death in the population-based (HR 2.58; 95% CI 2.38-2.80) and sibling-based (HR 2.61; 95% CI 2.19-3.10) analyses. Similar but weaker associations were also found for moderate SGA (HR 1.37; 95% CI 1.28-1.47 and HR 1.38; 95% CI 1.22-1.56, respectively).
The excess risk was most pronounced between 28 days and one year of age but remained throughout childhood. The greatest increase in risk was due to infection and neurological disease.
Although the study is one of the largest to date on this issue, the authors point out that some subgroup analyses, especially the analysis of cause-specific mortality, had limited statistical power using the sibling-based approach.