Table 1.
Clinical characteristics of subjects in the large discovery epidemiologic cohort (EPIC-Norfolk), in the biobank and electronic medical record (EMR)-based replication cohorts (MGBB-Asthma, EMR-Cortisol) and in an inhaled corticosteroid (ICS)-randomized clinical trial (Childhood Asthma Management Program, CAMP)
| Discovery cohort: EPIC-Norfolk | ||||
|---|---|---|---|---|
| Number of subjects | All subjects (n = 10,754) |
Asthma (n = 661) |
No asthma (n = 10,093) |
P-value* |
| Age, mean (SD) | 59.73 (9.0) | 59.24 (9.1) | 59.76 (8.9) | 0.14 |
| BMI kg/m2, mean (SD) | 26.19 (3.7) | 26.10 (3.9) | 26.20 (3.7) | 0.53 |
| Sex, n (%) | 0.08 | |||
| Female | 5,759 (53.6) | 376 (56.9) | 5,383 (53.3) | |
| Male | 4,995 (46.4) | 285 (43.1) | 4,710 (46.7) | |
| Race, n (%) | 0.76 | |||
| African American | 9 (0.1) | 1 (0.2) | 8 (0.1) | |
| White | 10,684 (99.7) | 655 (99.5) | 10,029 (99.8) | |
| Asian | 9 (0.1) | 1 (0.2) | 8 (0.1) | |
| Other | 9 (0.1) | 1 (0.2) | 8 (0.1) | |
| Smoking, n (%) | ||||
| Never | 5,012 (46.6) | 308 (46.6) | 4,704 (46.6) | 0.003 |
| Former | 4,573 (42.5) | 306 (46.3) | 4,267 (42.3) | |
| Current | 1,169(10.9) | 47(7.1) | 1,122(11.1) | |
| Replication cohort: MGBB-Asthma | ||||
| Number of subjects | All subjects (n = 610) |
Asthma (n = 287) |
No asthma (n = 323) |
P-value* |
| Age, mean (SD) | 32.7 (5.3) | 33.1 (6.6) | 32.4 (3.7) | 0.11 |
| BMI kg/m2, mean (SD) | 25.6 (6.5) | 28.3 (8.0) | 23.2 (3.1) | <2.2x10−16 2x10−16 |
| Sex, n (%) | ||||
| Female | 359 (58.9) | 208 (72.5) | 151 (46.7) | |
| Male | 251 (41.1) | 79 (27.5) | 172 (53.3) | |
| Race, n (%) | 9.8x10−3 | |||
| African American | 51 (8.4) | 34 (11.8) | 17 (5.3) | |
| White | 475 (77.9) | 222 (77.4) | 253 (78.3) | |
| Asian | 28 (4.6) | 10 (3.5) | 18 (5.6) | |
| Other | 56 (9.2) | 21 (7.3) | 35 (10.8) | |
| Inhaled corticosteroid intake, n (%) | <2.2x10−16 | |||
| No | 413 (67.7) | 90 (31.4) | 323 (100) | |
| Yes | 172 (28.2) | 172 (59.9) | 0 (0) | |
| Oral corticosteroid intake, n (%) | ||||
| No | 265 (43.4) | 265 (92.3) | NA | NA |
| Yes | 17 (2.8) | 17 (5.9) | NA | NA |
| Asthma severity scale | ||||
| No mild, moderate or severe asthma | 72 (11.8) | 72 (25.1) | NA | NA |
| Mild intermittent or persistent | 146 (23.9) | 146 (50.9) | NA | NA |
| Moderate persistent | 50 (8.2) | 50 (17.4) | NA | NA |
| Severe persistent | 19 (3.1) | 19 (6.6) | NA | NA |
| Smoking, n (%) | 1.2x10−3 | |||
| No | 482 (79) | 210 (73.2) | 272 (84.2) | |
| Yes | 128 (21) | 77 (26.8) | 51 (15.8) | |
| Validation cohort: Randomized clinical trial of ICS use - CAMP | ||||
| Number of subjects | All subjects (n = 1041) |
Baseline | End of trial | P-value* |
| (n = 560 at both time points) | ||||
| Age, mean (SD) | 8.8 (2.1) | 8.8 (2.1) | 12.8 (2.1) | <2.2x10−16 |
| BMI kg/m2, mean (SD) | 18.1 (3.5) | 18.0 (3.3) | 21.2 (4.5) | <2.2x10−16 |
| Sex, n (%) | NA | |||
| Female | 420 (40.3) | 201 (35.9) | 201 (35.9) | |
| Male | 621 (59.7) | 359 (64.1) | 359 (64.1) | |
| Race, n (%) | NA | |||
| African American | 138 (13.3) | 82 (14.6) | 82 (14.6) | |
| White | 711 (68.3) | 395 (70.5) | 395 (70.5) | |
| Hispanic | 98 (9.4) | 56 (10) | 56 (10) | |
| Other | 94 (9.0) | 27 (4.8) | 27 (4.8) | |
| Treatment, Steroid use (%) | NA | |||
| Budesonide | 311 (29.9) | 151 (27) | 151 (27) | |
| Nedocromil + Placebo | 730 (70.1) | 409 (73) | 409 (73) | |
| Validation cohort: Assessment of ICS effect in a clinical cohort EMR-Cortisol | ||||
| Number of subjects | All subjects (n = 2,235) |
Asthma (n = 383) |
No asthma (n = 1,852) |
P-value* |
| Age, mean (SD) | 56.1 (16.2) | 55.2 (16) | 56.3 (16.3) | 0.20 |
| Sex, n (%) | 3.9x10−14 | |||
| Female | 1377 (61.6) | 302 (78.9) | 1075 (58.0) | |
| Male | 858 (38.4) | 81 (21.1) | 777 (42.0) | |
| Race, n (%) | 1.4x10−3 | |||
| African American | 122 (5.5) | 34 (8.9) | 88 (4.8) | |
| White | 1959 (87.7) | 317 (82.8) | 1642 (88.7) | |
| Asian | 52 (2.3) | 7 (1.8) | 45 (2.4) | |
| Other | 102 (4.6) | 25 (6.5) | 77 (4.2 | |
| Inhaled steroid intake, n (%) | <2.2x10−16 | |||
| No | 2079 (93.0) | 268 (70) | 1811 (97.8) | |
| Yes | 156 (7.0) | 115 (30) | 41 (2.2) | |
| Adrenal Insufficiency diagnosis, n (%) | 0.03 | |||
| No | 1640 (73.4) | 263 (68.7) | 1377 (74.4) | |
| Yes | 595 (26.6) | 120 (31.3) | 475 (25.6) | |
Missing data: In MGBB-Asthma, BMI was missing for seven subjects; inhaled steroid intake was missing for 25 subjects; oral corticosteroid intake (OCS) and asthma severity were only extracted for asthma cases (therefore corresponding P-values cannot be determined) and OCS was not available for five subjects. Data on inhaled and oral medications were not available in EPIC-Norfolk cohort.
Significance of difference was evaluated using chi-squared test for categorical variables and two-sample t-test for continuous variables. In CAMP, the categorical variables sex, race and treatment did not change with time point, therefore NA is indicated for P-values.
Abbreviations: BMI, body mass index; SD, standard deviation; CAMP, Childhood Asthma Management Program