TABLE 2

iPFT Results by Pathophysiologic Classification

Entire Cohort, Median [IQR] or % (n/N)Obstructive, Median [IQR] or % (n/N)Restrictive, Median [IQR] or % (n/N)Mixed, Median [IQR] or % (n/N)P
Distribution51% (56/110)9% (10/110)40% (44/110)
Crs, % predicted69 [49–93]73 [52–96]64 [48–69]67 [47–89].24
FVC, % predicted77 [62–93]89 [75–106]61 [60–67]a70 [60–81]a<.001
FEV0.5, % predicted46 [39–57]43 [35–53]59 [57–62]b46 [40–57]c.002
FEV0.5 and/or FVC, % predicted64 [48–79]49 [39–69]94 [91–97]a69 [59–79]b,c<.001
FEF50%, % predicted20 [11–42]12 [8–21]74 [53–90]a24 [15–42]b,d<.001
FEF75%, % predicted13 [7–26]8 [6–16]49 [40–82]a16 [9–25]<.001
FEF85%, % predicted11 [7–22]8 [6–15]42 [34–58]a14 [8–19.7]b,d<.001
FEF25%–75%, % predicted16 [9–36]11 [7–18]71 [55–82]a21 [13–36]b,d<.001
TLC, % predicted91 [76–120]120 [106–138]72 [67–78]b78 [68–84]b<.001
FRC, % predicted101 [67–144]141 [104–173]69 [53–96]b67 [59–92]b<.001
RV, % predicted110 [73–169]165 [122–189]75 [63–112]b72 [55–97]b<.001
FRC and/or TLC, % predicted114 [101–137]127 [108–145]108 [93–129]b109 [95–121]b.002
RV and/or TLC, % predicted121 [105–150]134 [119–162]116 [105–146]b109 [94–133]a<.001
Degree of restriction (mild or moderate)49% (54/110)0% (0/56)100% (10/10)a100% (44/44)a<.001
Degree of obstruction (moderate or severe)75% (82/110)86% (48/56)0% (0/10)a78% (34/44)d<.001
BDRe66% (61/93)74% (35/47)25% (2/8)b63% (24/38).02
  • N = 56, 10, and 44, respectively, for all data except Crs, for which N = 48, 5, and 32, respectively. Symbols refer to P values from Dunn’s post hoc test or direct comparisons using the χ2 test. FEF25%–75%, forced expiratory flow midexpiratory phase; FEF50%, forced expiratory flow 50; FEF75%, forced expiratory flow 75; FEF85%, forced expiratory flow 85; FRC, functional residual capacity; RV, residual volume; —, not applicable.

  • a Different from obstructive; P < .001.

  • b Different from obstructive; P < .05.

  • c Different from restrictive; P < .05.

  • d Different from restrictive; P < .001.

  • e P value refers to the result of 1-way analysis of variance or a χ2 test comparing all 3 groups.