Table 1.
Association of Respiratory Phenotypes with Variables Used in Clustering Algorithm*
| LW-LA (n = 117) | LW-HA (n = 81) | TW-LA (n = 75) | HW-LA (n = 101) | HW-HA (n = 68) | P Value† | |
|---|---|---|---|---|---|---|
| Any wheezing | ||||||
| Low/minimal | 100 (85.5) | 57 (70.4) | 0 (0.00) | 0 (0.00) | 0 (0.00) | <0.01 |
| Early decrease | 9 (7.69) | 10 (12.3) | 71 (94.7) | 1 (0.99) | 0 (0.00) | |
| Late decrease | 6 (5.13) | 7 (8.64) | 4 (5.33) | 25 (24.8) | 16 (23.5) | |
| Frequent and persistent | 2 (1.71) | 7 (8.64) | 0 (0.00) | 75 (74.3) | 52 (76.5) | |
| Number of wheezing illnesses | ||||||
| Low/minimal | 117 (100) | 74 (91.4) | 2 (2.67) | 0 (0.00) | 2 (2.94) | <0.01 |
| Early resolution | 0 (0.00) | 0 (0.00) | 67 (89.3) | 3 (2.97) | 2 (2.94) | |
| Infrequent (and decreasing over time) | 0 (0.00) | 4 (4.94) | 6 (8.00) | 70 (69.3) | 46 (67.6) | |
| Frequent and persistent | 0 (0.00) | 3 (3.70) | 0 (0.00) | 28 (27.7) | 18 (26.5) | |
| Serum aeroallergen-specific IgE | ||||||
| Low/minimal | 104 (88.9) | 0 (0.00) | 48 (64.0) | 82 (81.2) | 0 (0.00) | <0.01 |
| Late onset | 10 (8.55) | 7 (8.64) | 4 (5.33) | 3 (2.97) | 3 (4.41) | |
| Intermediate | 0 (0.00) | 60 (74.1) | 14 (18.7) | 16 (15.8) | 19 (27.9) | |
| Early multiple | 3 (2.56) | 14 (17.3) | 9 (12.0) | 0 (0.00) | 46 (67.6) | |
| Aeroallergen-specific skin test responses | ||||||
| Low/minimal | 103 (88.0) | 26 (32.1) | 58 (77.3) | 95 (94.1) | 4 (5.88) | <0.01 |
| Intermediate | 14 (12.0) | 46 (56.8) | 15 (20.0) | 6 (5.94) | 48 (70.6) | |
| Early multiple | 0 (0.00) | 9 (11.1) | 2 (2.67) | 0 (0.00) | 16 (23.5) | |
| FEV1/FVC ratio‡ | ||||||
| Mean (Years 3–7) | 0.91 (0.88–0.94) | 0.90 (0.87–0.94) | 0.91 (0.88–0.93) | 0.90 (0.85–0.95) | 0.90 (0.86–0.93) | 0.50 |
| Variability (Years 3–7) | 0.09 (0.06–0.11) | 0.07 (0.05–0.11) | 0.07 (0.05–0.11) | 0.09 (0.06–0.12) | 0.10 (0.08–0.13) | <0.01 |
| IOS XA | ||||||
| Low | 29 (24.8) | 18 (22.2) | 9 (12.0) | 14 (13.9) | 9 (13.2) | 0.01 |
| Intermediate | 57 (48.7) | 46 (56.8) | 46 (61.3) | 45 (44.6) | 31 (45.6) | |
| High | 31 (26.5) | 17 (21.0) | 20 (26.7) | 42 (41.6) | 28 (41.2) | |
Definition of abbreviations: HA = high atopy; HW = high wheeze; IOS = impulse oscillometry; LA = low atopy; LW = low wheeze; TW = transient wheeze; XA = area of reactance.
*
Values are counts (percentages) or medians (interquartile range).
†
Chi-square for categorical data, F test for continuous data.
‡
For FEV1/FVC ratio we were unable to obtain a trajectory solution. Instead, these data were analyzed as continuous variables rather than group trajectories. To account for both the overall average and its variability over the last 4 years, for each participant, we derived his/her mean and its SD, which are presented under mean and variability.