Neonatal Phototherapy and Clinical Characteristics: The Danish National Patient Registry 2000–2016

Yuelian Sun,1– 4 Jesper Padkær Petersen,5 Chunsen Wu,6,7 Julie Werenberg Dreier,3,8 Rikke Damkjær Maimburg,9– 11 Tine Brink Henriksen,5 Jakob Christensen1,2 1Department of Neurology, Aarhus University Hospital, Aarhus, Denmark; 2Department of Clinical Medicine, Aarhus University, Aarhus, Denmark; 3National Centre for Register-Based Research, Aarhus University, Aarhus, Denmark; 4Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus University, Aarhus, Denmark; 5Department of Paediatrics, Clinical Institute, Aarhus University, Aarhus University Hospital, Aarhus, Denmark; 6Department of Clinical Research, University of Southern Denmark, Odense, Denmark; 7Department of Gynaecology and Obstetrics, Odense University Hospital, Odense, Denmark; 8Centre for Integrated Register-Based Research (CIRRAU), Aarhus University, Aarhus, Denmark; 9Department of Clinical Medicine, Aarhus University, Denmark; Department of Occupational Health, Aarhus University Hospital, Aarhus, Denmark; 10Department of Midwifery, University College of Northern Denmark, Hjørring, Denmark; 11School of Nursing and Midwifery, Western Sydney University, Blacktown, NSW, AustraliaCorrespondence: Yuelian Sun, Department of Neurology, Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark, Email ys@clin.au.dkPurpose: Phototherapy is the standard treatment for neonatal hyperbilirubinemia. It is important to collect data on phototherapy to support research related to the efficacy and safety of phototherapy. We explored the registration of phototherapy in the Danish National Patient Registry (DNPR) and the clinical characteristics of neonates treated with phototherapy.Methods: We identified children born alive in Denmark from 1 January 2000 through 30 November 2016 from the DNPR (N=1,044,502). We calculated the proportion of children registered that received phototherapy during the neonatal period and examined temporal trends, both nationwide and at the level of individual hospitals. In a sub-cohort of children born at Aarhus University Hospital (AUH) in 2002– 2016 (N=71,781), we analyzed the proportions of children registered that received phototherapy, according to sex, gestational age, birth weight, and neonatal characteristics, like Apgar score, birth asphyxia, and infections.Results: We identified 11,295 (1.1%) registered that received phototherapy. The proportions of children registered that received phototherapy differed among hospitals (range: 0 to 4.1%). Nationwide registration was low during the study period, but it increased to 1.8% in 2016. For the AUH sub-cohort the proportion of children registered with phototherapy averaged 4.4% (N=3182, range:3.9– 5.1%). The proportion of children registered with phototherapy was inversely correlated with gestational age and birth weight, and positively correlated with neonatal characteristics, including low Apgar score, birth asphyxia, and infections.Conclusion: Phototherapy was under-reported in the DNPR and the proportions of children registered that received phototherapy differed among hospitals. The non-compulsory policy for reporting treatment and care in hospitals to the DNPR might explain the variation. The most consistent reporting was observed among children born in an university hospital, where 4.4% of children registered that received phototherapy, and phototherapy was inversely associated with gestational age, birth weight, and positively associated with clinical characteristics like birth asphyxia, and infections.Keywords: Danish National Patient Registry, health administrative data, neonates, hyperbilirubinemia, neonatal jaundice, phototherapy