Table 3.
Differences in Characteristics between the Five CAMP Asthma Metabo-Endotypes
| CAMP Variable | Endotype 1 |
Endotype 2 |
Endotype 3 |
Endotype 4 |
Endotype 5 |
P Value | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| n = 99 | n = 375 | n = 45 | n = 207 | n = 185 | ||||||||
| Demographic characteristics | Sex, male, n (%) | 58 | (58.6%) | 229 | (61.1%) | 32 | (71.1%) | 125 | (60.4%) | 105 | (56.8%) | 0.496 |
| Age, mean (SD) | 13.06 | (2.38) | 12.91 | (2.10) | 12.32 | (1.61) | 12.95 | (2.19) | 13.08 | (2.12) | 0.288 | |
| BMI, mean (SD) | 21.18 | (4.60) | 21.43 | (4.66) | 20.74 | (4.93) | 21.31 | (4.19) | 21.84 | (5.31) | 0.598 | |
| Serum vitamin D, ng/ml, mean (%) | 33.94 | (14.61) | 31.55 | (14.15) | 30.49 | (13.59) | 28.3 | (14.31) | 26.75 | (11.86) | 4.83 × 10−5* | |
| Current smoking exposure, yes, n (%) | 9 | (9.1%) | 55 | (14.7%) | 6 | (13.3%) | 26 | (12.6%) | 32 | (17.3%) | 0.399 | |
| Race, White, n (%) | 72 | (72.7%) | 262 | (69.9%) | 32 | (71.1%) | 140 | (67.6%) | 124 | (67.0%) | 0.644 | |
| Lung phenotypes | Prebronchodilator FEV1, L, mean (SD) | 2.55 | (0.70) | 2.54 | (0.74) | 2.51 | (0.65) | 2.62 | (0.80) | 2.54 | (0.71) | 0.771 |
| Prebronchodilator FVC, L, mean (SD) | 3.29 | (0.99) | 3.29 | (0.94) | 3.08 | (0.85) | 3.36 | (1.05) | 3.30 | (0.91) | 0.518 | |
| Prebronchodilator FEV1/FVC, mean (SD) | 78.31 | (7.39) | 77.56 | (8.89) | 82.38 | (8.51) | 78.47 | (9.03) | 77.21 | (9.46) | 0.008* | |
| Postbronchodilator FEV1, L, mean (SD) | 2.78 | (0.78) | 2.76 | (0.77) | 2.68 | (0.67) | 2.85 | (0.85) | 2.79 | (0.75) | 0.614 | |
| Postbronchodilator FVC, L, mean (SD) | 3.32 | (1.00) | 3.34 | (0.94) | 3.12 | (0.83) | 3.4 | (1.07) | 3.36 | (0.92) | 0.506 | |
| Postbronchodilator FEV1/FVC, mean (SD) | 84.36 | (6.11) | 83.07 | (7.42) | 86.56 | (6.83) | 84.51 | (7.38) | 83.42 | (7.05) | 0.009* | |
| % predicted prebronchodilator FEV1/FVC, mean (SD) | 89.6 | (8.38) | 89.1 | (10.2) | 94.6 | (9.34) | 90.0 | (10.4) | 88.8 | (10.8) | 0.011* | |
| % predicted postbronchodilator FEV1/FVC, mean (SD) | 96.6 | (6.79) | 95.4 | (8.43) | 99.4 | (7.03) | 96.9 | (8.59) | 95.8 | (8.05) | 0.016* | |
| Indices of asthma severity | Use of corticosteroid since last visit, yes, n (%) | 21 | (21.2%) | 68 | (18.1%) | 8 | (17.8%) | 34 | (16.4%) | 29 | (15.7%) | 0.787 |
| Use of albuterol since last visit, yes, n (%) | 80 | (80.8%) | 313 | (83.5%) | 33 | (73.3%) | 170 | (82.1%) | 151 | (81.6%) | 0.530 | |
| Ever hospitalized for asthma, yes, n (%) | 10 | (10.1%) | 36 | (9.6%) | 2 | (4.4%) | 25 | (12.1%) | 19 | (10.3%) | 0.659 | |
| Ever visited ER for asthma, yes, n (%) | 33 | (33.3%) | 129 | (34.4%) | 10 | (22.2%) | 77 | (37.2%) | 54 | (29.2%) | 0.238 | |
| Allergic phenotypes and eosinophil concentrations | Log10 blood eosinophils (cells/μl), mean (SD) | 2.47 | (0.40) | 2.43 | (0.48) | 2.45 | (0.36) | 2.40 | (0.48) | 2.31 | (0.58) | 0.050* |
| Eosinophilic asthma (untransformed count > 300 cells/μl), yes, n (%) | 54 | (54.5%) | 196 | (52.3%) | 24 | (53.3%) | 104 | (50.2%) | 79 | (42.7%) | 0.343 | |
| Log10 IgE, kU/L, mean (SD) | 2.77 | (0.62) | 2.64 | (0.62) | 2.50 | (0.70) | 2.64 | (0.68) | 2.56 | (0.69) | 0.086 | |
| Number of positive skin prick tests, mean (SD) | 6.09 | (3.69) | 6.14 | (4.42) | 4.70 | (3.53) | 6.20 | (4.37) | 5.99 | (4.25) | 0.312 | |
| Prevalent hay fever, yes, n (%) | 47 | (47.5%) | 165 | (44.0%) | 29 | (64.4%) | 88 | (42.5%) | 93 | (50.3%) | 0.061 | |
| Prevalent atopic dermatitis, yes, n (%) | 23 | (23.2%) | 98 | (26.1%) | 15 | (33.3%) | 59 | (28.5%) | 60 | (32.4%) | 0.371 | |
Definition of abbreviations: BMI = body mass index; CAMP = Childhood Asthma Management Program; ER = emergency room.
P value is based on the ANOVA test for continuous variables and the chi-square test for categorical variables.
*
Significant at the 95% confidence level.