Table 1.
Summary Characterisation of Cluster Variables for 18-year Wheeze Clusters
| Cluster | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Variables |
Cluster
samples (n=309) |
Age 18
cohort (n=864) |
1
(n=38) |
2
(n=75) |
3
(n=30) |
4
(n=60) |
5
(n=76) |
6
(n=30) |
Separation of
the clusters # |
| Mean (SD) | |||||||||
| FEV1 * |
−0.15
(0.48) |
0 (0.46) |
0.43
(0.26) |
−0.27
(0.26) |
−0.62
(0.54) |
−0.32
(0.19) |
0.13
(0.29) |
−0.83
(0.33) |
({1},{2,4},{3,6
},{5}) |
| FVC † |
−0.02
(0.55) |
0 (0.51) |
0.58
(0.42) |
0.20
(0.44) |
−0.06
(0.50) |
−0.40
(0.35) |
−0.06
(0.39) |
−0.76
(0.46) |
({1},{2,3,5},{4
},{6}) |
| FEV1/FVC ‡ |
0.84
(0.08) |
0.87
(0.07) |
0.86
(0.034) |
0.78
(0.047) |
0.74
(0.10) |
0.89
(0.04) |
0.92
(0.04) |
0.83
(0.07) |
({1,6},{1,4},{2
,3},{4,5}) |
| FEF 25-75 § |
−0.39
(1.00) |
0 (0.98) |
0.23
(0.45) |
−1.13
(0.42) |
−1.48
(0.97) |
−0.34
(0.38) |
0.56
(0.70) |
−1.32
(0.67) |
({1,5},{2,3,6},
{4}) |
| BDR∥ |
7.49
(7.11) |
5.00
(5.78) |
5.85
(3.03) |
9.15
(4.65) |
22.68
(8.81) |
4.41
(5.31) |
3.11
(3.13) |
8.06
(3.93) |
({1,4,5},{1,2,6
},{1,4,6},{3}) |
|
BHR
DRS ¶ |
1.30
(0.42) |
1.13
(0.30) |
1.29
(0.26) |
1.26
(0.29) |
2.37
(0.33) |
1.16
(0.20) |
1.07
(0.20) |
1.37
(0.29) |
({1,2,4,5},{1,2
,3,4,6}) |
| FeNO ** | 45.36 (47.79) |
27.88 (31.92) |
76.24 (63.38) |
41.47 (46.72) |
65.35 (33.59) |
14.13 (6.16) |
24.17 (25.74) |
93.08 (52.17) |
({1,3,6},{1,2,3
},{2,5,4}) |
|
Log 10 Total
IgE †† |
183.19 (311.84) |
174.50 (343.88) |
335.68 (402.67) |
145.22 (248.47) |
140.68 (132.42) |
41.78 (51.56) |
92.96 (135.42) |
797.38 (558.52) |
({1,2,3,5},{1,6
},{2,3,4,5}) |
|
BTS Step of
Therapy (0-5) ‡‡ |
1.80
(0.72) |
1.79
(0.72) |
1.89
(0.88) |
2.00
(0.69) |
1.76
(0.62) |
1.29
(0.46) |
1.65
(0.56) |
2.28
(0.75) |
({1,2,3,6},{3,5
,4},{1,2,3,5}) |
|
Age wheeze
1st appeared §§ ( Years) |
8.00
(5.58) |
7.34
(5.29) |
5.6
(4.59) |
4.83
(4.14) |
4.75
(4.19) |
14.02
(2.77) |
8.83
(5.56) |
8.12
(5.01) |
({1,2,3},{1,6},
{4,5,6}) |
|
Prevalence
(%) |
|||||||||
| Rhinitis at 18 | 62.99 | 35.75 | 71.8 | 61.8 | 96.6 | 46.7 | 50.6 | 86.2 |
({1,2,4,5},{1,2
,6},{3,6}) |
| Eczema at 18 | 17.32 | 12.32 | 15.4 | 13.3 | 57.1 | 16.7 | 12.0 | 6.9 | ({1,2,4,5,6},3) |
|
∥ ∥
Atopy at
18 |
63.13 | 41.27 | 83.3 | 57.6 | 100 | 33.3 | 50.8 | 85.7 |
({1,2,6},{1,3,6
},{2,4,5}) |
Age 18 cohort refers to the population at 18-years who attended for a full visit and therefore had full available objective data.
FEV1 = Forced expiratory volume in first second in litres (L) with standard error (S.E.) at 18-years. It is gender and height adjusted.
FVC = Forced vital capacity in litres (L) with standard error (S.E.) at 18-years. It is gender and height adjusted.
FEV1/FVC = ratio of FEV1 to FVC at 18-years.
FEF25-75% = Forced expiratory flow 25-75% in litres per second (L/s) with standard error (S.E.) at 18-years. It is gender and height adjusted.
BDR refers to %FEV1 Bronchodilator reversibility: to 600 micrograms inhaled salbutamol at 18-years.
BHR DRS refers to a continuous dose-response (DRS) measure of bronchial hyperresponsiveness (BHR) expressed as Log10 (DRS+10). Higher values infer greater BHR at 18-years.
FeNO refers to Log 10 Fractional exhaled Nitric Oxide measured in parts per billion (ppb) at 18-years at 18-years.
Log 10 Total IgE at 18-years.
BTS (British Thoracic Society) Step of Therapy (0-4); where level of treatment increases with step.
Age wheeze 1st appeared (in years; determined from prospectively collected data throughout the 18-years of the cohort).
Atopy refers to positive skin prick test (>3mm wheal diameter) to at least allergen in standard test panel at 18-years.
ANOVA for continuous variables indicates that there is a significant difference in the statistics across the six clusters (all p-values<0.0001). Chi-squared tests on the binary variables give the same conclusion. The information provided in this column is to display the groupings. Pair-wised t-tests were applied to continuous variables, and pair-wised proportion tests were applied to binary variables both with Bonferonni multiple testing corrections. Numbers included within a pair of curly brackets indicate the statistics within those clusters are not significantly different from each other after adjusting for multiple testing. Numbers in different pairs of curly brackets indicate that there is a significant difference between those grouped clusters.