The effect of primary graft dysfunction on survival after lung transplantation

Abstract

Rationale: Primary graft dysfunction is a severe acute lung injury syndrome after lung transplantation. Long-term outcomes of subjects with primary graft dysfunction have not been studied.

Objectives: We sought to test the relationship of primary graft dysfunction with both short- and long-term mortality using a large registry.

Methods: We used data collected on 5,262 patients in the United Network for Organ Sharing/International Society of Heart and Lung Transplantation registry between 1994 and 2000. We assessed outcomes in all subjects; to assess potential bias from the effects of early mortality, we also evaluated subjects who survived at least 1 year, using Cox proportional hazards models with time-varying covariates.

Main results: The overall incidence of primary graft dysfunction was 10.2% (95% confidence intervals [CI], 9.2, 10.9). The incidence did not vary by year over the period of observation (p = 0.22). All-cause mortality at 30 days was 42.1% for primary graft dysfunction versus 6.1% in patients without graft dysfunction (relative risk = 6.95; 95% CI, 5.98, 8.08; p < 0.001); among subjects who died by 30 days, 43.6% had primary graft dysfunction. Among patients surviving at least 1 year, those who had primary graft dysfunction had significantly worse survival over ensuing years (hazard ratio, 1.35; 95% CI, 1.07, 1.70; p = 0.011). Adjustment for clinical variables including bronchiolitis obliterans syndrome did not change this relationship.

Conclusion: Primary graft dysfunction contributes to nearly half of the short-term mortality after lung transplantation. Survivors of primary graft dysfunction have increased risk of death extending beyond the first post-transplant year.

Figure 1.

Change in incidence of primary graft dysfunction (PGD) by year of transplant. The χ² test for trend p value was 0.22.

Figure 2.

Overall survival in patients with PGD and those without. The analysis time is years. The hatch marks represent censored patients, and the number at risk at the start of a specified interval appears along the x axis.

Figure 3.

Overall survival in patients who survived at least 1 year. The analysis time is years. The log-rank p value for the comparison of PGD to those without PGD is 0.014.