Table 1.
Respiratory Evaluations in Extremely Preterm Participants and Full-Term Control Subjects at 19 Years of Age
| All EP (n = 123) | Control Subjects (n = 64) | EP with BPD (n = 87) | EP with No BPD (n = 36) | EP vs. Control Subjects [Difference in Means (95% CI)] | BPD vs. No BPD [Difference in Means (95% CI)] | ||
|---|---|---|---|---|---|---|---|
| Prebronchodilator | |||||||
| FEV1, L | 2.87 ± 0.72 (1.29 to 4.66) | 3.56 ± 0.65 (2.30 to 5.29) | 2.77 ± 0.69 (1.29 to 4.35) | 3.10 ± 0.73 (1.56 to 4.66) |
−0.69 (−0.90 to −0.48)* | −0.33 (−0.60 to −0.06)† | |
| FEV1z-score | −1.61 ± 1.17 (−5.06 to 0.68) | −0.29 ± 0.89 (−2.24 to 1.92) | −1.83 ± 1.17 (−5.06 to 0.68) | −1.05 ± 0.99 (−3.87 to 0.26) |
−1.31 (−1.64 to −0.98)* | −0.78 (−1.19 to −0.37)† | |
| FVC, L | 3.71 ± 0.89 (1.31 to 6.09) | 4.25 ± 0.87 (2.35 to 6.09) | 3.68 ± 0.87 (1.31 to 5.55) | 3.79 ± 0.93 (2.20 to 6.09) |
−0.53 (−0.80 to −0.27)* | −0.11 (−0.45 to 0.24) | |
| FVC z-score | −0.76 ± 1.06 (−4.45 to 1.59) | −0.00 ± 0.93 (−2.24 to 1.82) | −0.84 ± 1.07 (−4.45 to 1.59) | −0.59 ± 1.02 (−2.84 to 0.87) |
−0.76 (−1.07 to −0.45)* | −0.24 (−0.64 to 0.15) | |
| FEV1/FVC% | 0.78 ± 0.10 (0.52 to 1.00) | 0.85 ± 0.08 (0.60 to 0.99) | 0.76 ± 0.10 (0.52 to 1.00) | 0.82 ± 0.08 (0.65 to 1.00) |
−0.07 (−0.10 to −0.04)* | −0.07 (−0.10 to −0.03)* | |
| FEV1/FVC z-score | −1.33 ± 1.24 (−3.95 to 2.28) | −0.42 ± 1.13 (−3.06 to 2.21) | −1.57 ± 1.21 (−3.95 to 2.28) | −0.75 ± 1.14 (−2.62 to 2.18) |
−0.91 (−1.28 to −0.55)* | −0.83 (−1.29 to −0.37)* | |
| FEF25–75, L/min | 2.62 ± 1.03 (0.58 to 6.71) | 3.88 ± 1.09 (1.56 to 6.95) | 2.41 ± 0.97 (0.58 to 6.71) | 3.14 ± 0.98 (1.18 to 6.01) |
−1.26 (−1.58 to −0.94)* | −0.73 (−1.13 to −0.33)* | |
| FEF25–75z-score | −1.86 ± 1.22 (−5.21 to 1.75) | −0.44 ± 1.11 (−2.64 to 2.08) | −2.14 ± 1.19 (−5.21 to 1.75) | −1.17 ± 1.02 (−3.66 to 0.91) |
−1.41 (−1.77 to −1.05)* | −0.97 (−1.41 to −0.53)* | |
| Post-bronchodilator | |||||||
| Oxygen saturation, % | 97.49 ± 1.23 (93.00 to 100.00) (n = 120) | 97.80 ± 1.16 (94.00 to 100.00) (n = 64) | 97.45 ± 1.36 (93.00 to 100.00) (n = 86) | 97.59 ± 0.82 (96.00 to 99.00) (n = 34) |
−0.31 (−0.67 to 0.06) | −0.13 (−0.62 to 0.35) | |
| Post-FEV1, L | 3.12 ± 0.70 (1.47 to 4.90) (n = 121) | 3.71 ± 0.73 (2.36 to 5.58) (n = 64) | 3.04 ± 0.68 (1.47 to 4.63) (n = 86) | 3.32 ± 0.70 (1.93 to 4.90) (n = 35) |
−0.60 (−0.81 to −0.38)* | −0.28 (−0.56 to 0.00)† | |
| Post-FEV1z-score | −1.04 ± 1.08 (−4.29 to 1.13) (n = 121) | 0.05 ± 0.90 (−2.08 to 2.37) (n = 64) | −1.23 ± 1.12 (−4.29 to 0.94) (n = 86) | −0.54 ± 0.98 (−2.72 to 0.88) (n = 35) |
−1.08 (−1.40 to −0.77)* | −0.66 (−1.06 to −0.27)‡ | |
| Percentage change in FEV1 | 8.83 ± 7.98 (−7.40 to 35.52) (n = 121) | 4.34 ± 5.59 (−7.38 to 20.38) (n = 64) | 9.60 ± 7.50 (−6.47 to 35.52) (n = 86) | 6.93 ± 8.87 (−7.40 to 35.19) (n = 35) |
4.49 (2.28 to 6.69)* | 2.66 (−0.19 to 5.51) | |
| Change in FEV1 > 12% | 32/121 (26.5%) | 4/64 (6.3%) | 28/86 (32.6%) | 4/35 (11.4%) |
5.39 (1.81 to 16.04)‡§ | 3.74 (1.20 to 11.64)†§ | |
| Post-FVC, L | 3.76 ± 0.85 (2.00 to 6.19) (n = 121) | 4.23 ± 0.90 (2.37 to 6.14) (n = 64) | 3.74 ± 0.82 (2.00 to 5.39) (n = 86) | 3.83 ± 0.93 (2.26 to 6.19) (n = 35) |
−0.47 (−0.73 to −0.21)* | −0.09 (−0.43 to 0.25) | |
| Post-FVC z-score | −0.68 ± 0.96 (−3.52 to 1.48) (n = 121) | −0.04 ± 0.98 (−2.30 to 2.16) (n = 64) | −0.74 ± 0.94 (−3.52 to 1.48) (n = 86) | −0.54 ± 0.98 (−2.72 to 0.88) (n = 35) |
−0.64 (−0.94 to −0.35)* | −0.19 (−0.58 to 0.19) | |
| Post-FEV1/FVC | 0.83 ± 0.09 (0.54 to 1.00) (n = 121) | 0.88 ± 0.07 (0.67 to 1.00) (n = 64) | 0.82 ± 0.10 (0.54 to 1.00) (n = 86) | 0.87 ± 0.07 (0.69 to 1.00) (n = 35) |
−0.05 (−0.08 to −0.02)* | −0.06 (−0.09 to −0.02)* | |
| Post-FEV1/FVC z-score | −0.56 ± 1.27 (−4.27 to 2.37) (n = 121) | 0.15 ± 1.06 (−2.56 to 2.27) (n = 64) | −0.79 ± 1.29 (−4.27 to 2.37) (n = 86) | −0.00 ± 1.03 (−2.24 to 2.15) (n = 35) |
−0.71 (−1.08 to −0.35)* | −0.79 (−1.25 to −0.33)* | |
| Post–FEF25–75, L/min | 3.29 ± 1.12 (0.73 to 7.19) (n = 121) | 4.47 ± 1.18 (2.06 to 7.22) (n = 64) | 3.10 ± 1.14 (0.73 to 7.19) (n = 86) | 3.76 ± 0.94 (1.48 to 6.73) (n = 35) |
−1.17 (−1.52 to −0.83)* | −0.66 (−1.10 to −0.22)‡ | |
| Post–FEF25–75z-score | −1.03 ± 1.23 (−4.58 to 2.07) (n = 121) | 0.16 ± 1.06 (−2.33 to 2.54) (n = 64) | −1.28 ± 1.28 (−4.58 to 2.07) (n = 86) | −0.44 ± 0.85 (−2.55 to 1.46) (n = 35) |
−1.19 (−1.55 to −0.84)* | −0.84 (−1.29 to −0.39)* | |
| FeNO | |||||||
| FeNO, ppb | 13.9 ± 11.1 (0.0 to 56.7) (n = 117) | 24.4 ± 24.7 (0.0 to 133.7) (n = 62) | 13.4 ± 10.0 (0.0 to 51.3) (n = 83) | 15.2 ± 13.5 (0.0 to 56.7) (n = 34) |
−10.47 (−15.77 to −5.18)* | −1.77 (−8.64 to 5.10) | |
| FeNO > 40 ppb | 6/117 (5.1%) | 9/62 (14.5%) | 3/83 (3.6%) | 3/34 (8.8%) |
0.32 (0.11 to 0.94)†§ | 0.39 (0.07 to 2.02)§ | |
| Clinical symptoms (self-report questionnaire) | |||||||
| Asthma diagnosis ever | 50/121 (41.3%) | 21/61 (34.3%) | 43/87 (49.4%) | 7/34 (20.6%) |
1.34 (0.71 to 2.54)§ | 3.80 (1.49 to 9.57)‡§ | |
| Symptoms in the last year | 24/121 (19.8%) | 17/62 (27.4%) | 19/87 (21.8%) | 5/34 (14.7%) |
0.65 (0.32 to 1.34)§ | 1.62 (0.55 to 4.76)§ | |
| Wheeze during or after exercise | 32/121 (26.5%) | 19/61 (31.2%) | 25/87 (28.7%) | 7/34 (20.6%) |
0.79 (0.40 to 1.56)§ | 1.56 (0.60 to 4.03)§ | |
| Treated in the last year for respiratory or chest problems | 16/121 (13.2%) | 12/60 (20.0%) | 13/87 (14.9%) | 3/34 (8.8%) |
0.61 (0.27 to 1.39)§ | 1.82 (0.48 to 6.82)§ | |
| Currently using inhalers | 28/126 (22.2%) | 11/64 (17.2%) | 24/90 (26.7%) | 4/36 (11.1%) |
1.38 (0.64 to 2.98)§ | 2.91 (0.93 to 9.09)§ | |
| Hospital admission for “breathing difficulties” (last 12 m) | 1/119 (0.8%) | 1/62 (1.6%) | 1/87 (1.2%) | 0/32 (0.0%) | 0.52 (0.03 to 8.41)§ | — | |
Definition of abbreviations: BPD = bronchopulmonary dysplasia; CI = confidence interval; EP = extremely preterm; FEF25–75 = mean forced expiratory flow between 25% and 75% of the FVC; FeNO = fractional exhaled nitric oxide.
Data are shown as mean ± SD (range) or n (%).
*
P < 0.001.
†
P < 0.05.
‡
P < 0.01.
§
The odds ratio (95% CI) was reported for categorical variables.