Impact of hospitalisation burden on mortality in adult congenital heart disease: A nationwide population study

Background

As the hospitalisation rate for adults with congenital heart disease (ACHD) increases, information regarding the outcome of these hospitalisations is needed.

Method

This retrospective cohort study utilized the Danish National Patient Registry to identify ACHD patients who reached 18 years old ≥1st Jan 1995 and followed them to either death or 31st Dec 2018. Each patient was matched 1:10 to controls. Mortality was estimated as the mortality rate per 100 patient-years (/100PY) and the association of hospitalisation burden and mortality was examined.

Results

7830 ACHD patients were included (50.5 % female, 64.7 % mild ACHD, 28.1 % moderate ACHD and 7.2 % severe ACHD) and followed for a median of 8.6 years. When not having any hospitalisation in the past one year, the mortality rate for all ACHD patients was 0.04/100PY[95 % confidence interval: 0.02;0.05]. Having any hospitalisation in the past year increased the mortality rate by 5.2-fold to 0.55/100PY[0.42;0.72]. In mild ACHD, the mortality rate increased by 10.7-fold. In moderate ACHD, it increased by 4.8-fold, while in severe ACHD, no significant increase in mortality was observed. Compared to the matched controls, mild ACHD patients also had an increase in excess mortality from 0.8-fold when having no hospitalisation to 1.6-fold when having any hospitalisation in the past year. This increase in excess mortality was however not observed in moderate and severe ACHD.

Conclusion

Hospitalisation in the past year has a greater impact on mortality in mild ACHD patients than in other ACHD severities. This indicates a greater gap in the follow-up care needed by patients with mild ACHD.