FIGURE 3.

Median dd-cfDNA% levels in clinically stable lung allograft recipients >2 y posttransplant do not vary by recipient sex, relative FEV₁ at measurement, history of acute cellular rejection, or age. We assessed whether dd-cfDNA% levels were associated with demographics or relevant clinical history. A, Subject sex vs median dd-cfDNA% (P = 0.26). B, Median dd-cfDNA% vs median FEV₁ (relative to the average peak baseline FEV₁ posttransplant) at each measurement (r = 0.100, P = 0.48). C, Acute cellular rejection history vs dd-cfDNA% (P = 0.16). D, Subject age vs median dd-cfDNA% (r = −0.264, P = 0.06). Mann-Whitney U test was used to compare baseline dd-cfDNA% by sex and history of acute cellular rejection. Spearman’s correlation was used to assess the relationships between FEV₁ or age and dd-cfDNA%. In the box and whisker plots, the following are depicted: median value = line, interquartile range = box, error bars = minimum and maximum values. dd-cfDNA, donor-derived, cell-free DNA; FEV₁, forced expiratory volume in 1 s.