Methods: The Kids’ Inpatient Database (KID) is a nationally representative survey conducted every 3 years in the United States. Birth hospitalization data from KID were utilized to estimate the prevalence of CLD (ICD-9 = 770.7) among US infants in 2003–2012 overall and as a function of coincident codes for GA (ICD-9 = 765.21–765.29, reported in 2-week intervals). The prevalence of CLD among 32 wGA infants was imputed based on the distribution of CLD cases as a function of wGA. KID data from 2015 were not available due to the transition to ICD-10 coding.
Results: 31,984 infants had a CLD diagnosis across the 4 years, representing 0.2% of US births. The prevalence of CLD declined from 20.8 to 19.5 per 10,000 between 2003 and 2012. 25,554 infants with CLD (80%) had GA coded in the database. The percentage of CLD infants born at <27 wGA increased from 44% in 2003 to 52% in 2012, whereas the percentage at ≥29 wGA decreased from 27% to 21% (Figure). Overall, the percentages born at 31–32, 33–34, and >34 wGA were 5.7%, 2.2%, and 1.2%, respectively. An estimated 5.7% of infants with CLD were born at ≥32 wGA, representing 0.9 of every 10,000 US births or approximately 350 infants annually.
Conclusion: Fewer than 400 infants are born at ≥32 wGA and diagnosed with CLD annually in the United States. The rationale for excluding this small but high-risk group of infants from the population recommended for RSV immunoprophylaxis is not clear.
Funded by AstraZeneca
C. S. Ambrose,
K. Mavunda, AstraZeneca: Speaker's Bureau , Speaker honorarium .