Variables Explaining the Duration of Hospitalization in Children under Two Years of Age Admitted with Acute Airway Infections: Does Respiratory Syncytial Virus Have a Direct Impact?

Zusammenfassung

Hintergrund: Die Hospitalisierungsdauer bei akuten Atemwegsinfektionen wird durch mehrere Variablen beeinflusst. Sie ist ein wichtiger Parameter in der Qualitätskontrolle. Bisher ist nicht bekannt, in wieweit das RS-Virus (RSV) selbst im Vergleich zu anderen Erregern einen schwereren Verlauf bedingt, wenn die Patienten für die übrigen Variablen vergleichbar sind. Methode: Kinder unter 2 Jahre, die wegen einer tiefen Atemwegsinfektion zwischen 1996 und 2000 in einem von 3 Krankenhäusern (1 Universitätsklinik und 2 periphere Kinderkliniken) in Schleswig-Holstein hospitalisiert wurden, wurden in einer ungematchten Fall-Kontroll-Studie untersucht. Fälle waren die Kinder, die mittels Multiplex-RT-PCR Respiratory Syncytial Virus (RSV) positiv getestet wurden. Eine Kontrollgruppe bestand aus Kindern, die in der PCR negativ waren, und eine zweite Kontrollgruppe aus den Kindern, die nicht mittels PCR untersucht wurden. Da nur 4 - 5 % in der letzteren Gruppe und damit 2 % der gesamten Studienpopulation missklassifiziert wurden, konnte diese Gruppe mitverwendet werden. Ergebnis: Die mediane Hospitalisierungsdauer betrug 7 Tage; 9 Tage in der RSV-Gruppe, 8 bzw. 6 Tage in der RSV-negativen bzw. nicht-PCR-getesteten Gruppe. Die Hospitalisierungsdauer verkürzte sich über den Untersuchungszeitraum hinweg. Sie wurde am besten vorhergesagt durch das junge Alter, Vorliegen einer Grundkrankheit, Krankheitsform (Pneumonie oder Bronchiolitis), Frühgeburtlichkeit, früheres epidemiologisches Jahr und interkostale Einziehungen. Nicht prädiktiv waren: RSV-Ätiologie, Behandlungszentrum, Dauer der Symptome vor Aufnahme, bronchiale Obstruktion, C-reaktives Protein und Infiltrationen auf dem Röntgenthoraxbild bei der stationären Aufnahme. Schlussfolgerungen: Die RSV-Ätiologie beeinflusst die Hospitalisierungsdauer nur indirekt über die Prädilektion für das besonders junge Alter und bestimmte Grundkrankheiten. Trotz erheblicher Unterschiede der Patientenklientel zwischen Zweit- und Drittversorgungszentren und lokalen Unterschieden im Patientenmanagement, beeinflusste der Behandlungsort die Hospitalisierungsdauer nicht signifikant. Es gibt jedoch Raum für eine weitere Rationalisierung der Behandlung.

Abstract

Background: Duration of hospitalization is influenced by many factors. It is an important parameter for quality of care. So far it is unknown, whether respiratory syncytial virus (RSV) etiology itself contributes to the time in hospital. Method: Children under 2 years of age admitted with a lower respiratory tract infection in 3 hospitals (1 tertiary and 2 secondary centers) in northern Germany were included in an unmatched, hospital-based case-control study. Cases were children tested positive for RSV by multiplex RT-PCR. One control group consisted of children tested negative for RSV in the multiplex-RT-PCR and a second control group consisted of patients in whom no PCR was done. Since only 4 to 5 % in the latter group and thus 2 % of the study population were misclassified, this group could be involved in the analysis. Results: The median days of hospitalization was 7 days; 9 days in the RSV-positive group, 8 and 6 days in the RSV-negative and non-PCR group, respectively. The time in hospital was diminishing over the 4 year observation period. Duration of hospitalization was best predicted by - young age, presence of an underlying condition, disease entity - being pneumonia or bronchiolitis, prematurity, earlier epidemiologic year and intercostal retractions. Not predictive were: RSV-etiology, center, duration of illness, wheezing, C-reactive protein level and consolidation on the chest x-ray (all on admission). Conclusions: RSV-etiology is influencing the duration of hospitalization only indirectly via its predilection for the very young age and certain underlying conditions - not by RSV itself. In spit of considerable variation of patient populations between secondary and tertiary care facilities and locally different care practices, the treatment center pre se did not influence the duration of hospitalization significantly. Further rationalization of treatment is, however, possible.

Schlüsselwörter

Fall-Kontroll-Studie - Hospitalisierung - multivariat - Respiratory-Syncytial-Virus

Key words

Case-control - hospitalization - multivariat analysis - respiratory syncytial virus

References

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