Hospital admissions for lower respiratory tract infections in children born moderately/late preterm

ObjectiveTo evaluate the frequency and predictors of hospital admissions for lower respiratory tract infections (LRTIs) in moderately preterm (MP, 32(+0) to 33(+6) weeks) and late preterm (LP, 34(+0) to 36(+6) weeks) infants compared to term (T 37 weeks) and very preterm (VP, <32(+0) weeks) infants. Study DesignThis national register-based study covered all infants born in Finland in 1991-2008. Data on 1018256 infants were analyzed in four gestational age-based groups: VP (n=6329), MP (n=6796), LP (n=39928), and T (n=965203) groups. Data on hospital admissions due to bronchiolitis/bronchitis and pneumonia were collected up to the age of 7 years. ResultsHospital admissions for LRTIs were more common in the MP and LP groups than in the T group but less frequent than in the VP group: bronchiolitis/bronchitis (VP 24.4%, MP 13.9%, LP 9.5%, and T 5.6%) and pneumonia (VP 8.8%, MP 4.5%, LP 3.3%, and T 2.4%). Compared to the term group, MP and LP birth predicted bronchiolitis/bronchitis (MP OR 1.89; 95%CI 1.75-2.03, LP 1.51; 1.45-1.56) and pneumonia (MP 1.49; 1.32-1.67, LP 1.25; 1.18-1.33) admissions. Statistically significant risk factors for LRTIs included maternal smoking, cesarean section, male sex, admission to a neonatal unit and ventilator therapy. In addition, being first-born, being born SGA and neonatal antibiotic therapy were associated with bronchiolitis/bronchitis. ConclusionsMP and LP births, in addition to VP birth, have a significant impact on respiratory infectious morbidity and the need of hospital admissions for LRTIs.