Preterm birth-associated neurodevelopmental impairment estimates at regional and global levels for 2010.

backgroundIn 2010, there were an estimated 15 million preterm births worldwide (<37 wk gestation). Survivors are at risk of adverse outcomes, and burden estimation at global and regional levels is critical for priority setting.

methodsSystematic reviews and meta-analyses were undertaken to estimate the risk of long-term neurodevelopmental impairment for surviving preterm babies according to the level of care. A compartmental model was used to estimate the number of impaired postneonatal survivors following preterm birth in 2010. A separate model (DisMod-MR) was used to estimate years lived with disability (YLDs) for the global burden of disease 2010 study. Disability adjusted life years (DALYs) were calculated as the sum of YLDs and years of life lost (YLLs).

resultsIn 2010, there were an estimated 13 million preterm births who survived beyond the first month. Of these, 345,000 (2.7%, uncertainty range: 269,000-420,000) were estimated to have moderate or severe neurodevelopmental impairment, and a further 567,000 (4.4%, (445,000-732,000)) were estimated to have mild neurodevelopmental impairment. Many more have specific learning or behavioral impairments or reduced physical or mental health. Fewest data are available where the burden is heaviest. Preterm birth was responsible for 77 million DALYs, 3.1% of the global total, of which only 3 million were YLDs.

conclusionMost preterm births (>90%) survive without neurodevelopmental impairment. Developing effective means of prevention of preterm birth should be a longer term priority, but major burden reduction could be made immediately with improved coverage and quality of care. Improved newborn care would reduce mortality, especially in low-income countries and is likely to reduce impairment in survivors, particularly in middle-income settings.