Increased Risk for Bronchitis after Discharge in Non-vaccinated Very Low Birth Weight Infants

Abstract

Background: In very low birth weight (VLBW) infants, obstructive bronchitis is a frequent cause of hospital re-admission. For VLBW infants, early vaccinations starting at 2 months after birth have been recommended.

Objective: To analyze risk factors for bronchitis during the first year after discharge and the effects of in-hospital standard vaccination (hexavalent/pneumococci) and/or RSV immunoprophylaxis with palivizumab.

Methods: A standardized questionnaire was sent to the parents of VLBW infants 7 month after discharge. The reported episodes of bronchitis were correlated with clinically recorded parameters including risk factors for pulmonary morbidity. The effects of in-hospital vaccination were assessed in a subgroup discharged after day 60.

Results: A sample of 1 967 responses of infants born 2009–2011 was analyzed. Risk factors for bronchitis were male gender and older siblings. 24% of the population had episodes of bronchitis. In the subgroup discharged after day 60, episodes of bronchitis were reported for 31% of infants who were not vaccinated in-hospital. A significant reduction of the bronchitis rate was found in infants who received palivizumab±standard vaccination (17% bronchitis, p=0.003). Interestingly, in-hospital standard vaccination without RSV immunoprophylaxis was protective (20% bronchitis; p=0.037) as well.

Conclusions: Non-vaccinated male VLBW infants with older siblings are at increased risk for bronchitis during the first year after discharge. Vaccination according to schedule seems to have protective effects, while underlying mechanisms are unknown. The rate of timely vaccination in preterm infants should be increased.

Zusammenfassung

Hintergrund: Obstruktive Bronchitiden sind eine häufige Ursache von Krankenhaus-Wiederaufnahmen sehr kleiner Frühgeborener. Für diese Patientengruppe wird ein Beginn der Impfungen 2 Monate nach der Geburt empfohlen.

Fragestellung: Es sollten Bronchitis-Risikofaktoren im ersten Lebensjahr und der Effekt zeitgerechter im Krankenhaus durchgeführter Impfungen (Standard Impfung mit hexavalenten- und Pneumokokken-Impfstoff sowie Respiratory Syncytial Virus Immunprophylaxe mit Palivizumab) analysiert werden.

Methoden: 7 Monate nach Entlassung wurde den Eltern sehr kleiner Frühgeborener ein Standardfragebogen zugesandt. Die berichteten Bronchitiden wurden mit klinischen Parametern, inklusive Risikofaktoren typischer Lungenerkrankungen, korreliert. Der Effekt im Krankenhaus erfolgter Impfungen wurde bei Patienten, die nach Lebenstag 60 entlassen wurden, analysiert.

Ergebnisse: Wir werteten 1 967 Antwortbögen der Jahre 2009–2011 aus. Bronchitis-Risikofaktoren waren männliches Geschlecht und Vorhandensein älterer Geschwister. Bronchitiden zeigten 24% der Population. Die Bronchitisrate lag bei 31% der nicht geimpften Kinder, die nach dem 60. Lebenstag entlassen wurden und sank auf 17% bei Kindern, die mit Palivizumab±Standard-Impfstoff geimpft wurden (p=0,003). Interessanterweise war eine zeitgerechte Standard-Impfung (im Krankenhaus; ohne Palivizumab) ebenfalls mit einer niedrigen Bronchitisrate assoziiert (Rate: 20%, p=0,037).

Schlussfolgerung: Nicht-Geimpfte männliche Frühgeborene mit älteren Geschwistern haben im ersten Lebensjahr ein erhöhtes Bronchitis-Risiko. Zeitgerechte Impfungen reduzieren die Bronchitisrate. Die Impfrate von kleinen Frühgeborenen in der Klinik sollte erhöht werden.

Key words

bronchitis - premature neonates - vaccination effect - vaccination

Schlüsselwörter

Bronchitis - unreife Frühgeborene - Impfeffekt - Impfungen

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