Table 1.
Characteristics of SAPPHIRE participants included in the analysis
| Characteristic | Total (n=7,627) |
African American (n=4,558) |
European American (n=2,391) |
P-value* |
|---|---|---|---|---|
| Age in years - mean ± SD | 34.3 ± 14.3 | 34.1 ± 14.0 | 35.5 ± 14.8 | < 0.001 |
| Female sex – no. (%) | 4,921 (64.5%) | 3,008 (66.0%) | 1,494 (62.5%) | 0.004 |
| Race-ethnicity – no. (%) | -- | -- | -- | -- |
| African American | 4,558 (59.8%) | 4,558 (100%) | -- | -- |
| European American | 2,391 (31.3%) | -- | 2,391 (100%) | -- |
| Latino | 242 (3.2%) | -- | -- | -- |
| Other† | 436 (5.7%) | -- | -- | -- |
| Ancestry – proportion African/European ± SD‡ | -- | 0.831/0.169 ± 0.091 | 0.013/0.987 ± 0.025 | <0.001 |
| Asthma – no. (%) | -- | -- | -- | < 0.001 |
| Childhood onset | 4,348 (57.0%) | 2,603 (57.1%) | 1,323 (55.3%) | -- |
| Adult onset | 1,804 (23.7%) | 1,024 (22.5%) | 646 (27.0%) | -- |
| BMI – mean ± SD | 30.7 ± 9.0 | 31.9 ± 9.3 | 28.8 ± 8.0 | < 0.001 |
| Smoking status | -- | -- | -- | < 0.001 |
| Never smoker | 5,422 (71.1%) | 3,203 (70.3%) | 1,709 (71.5%) | -- |
| Past smoker | 894 (11.7%) | 443 (9.7%) | 384 (16.1%) | -- |
| Current smoker | 1,299 (17.0%) | 911 (20.0%) | 297 (12.4%) | -- |
| Household income§ | -- | -- | -- | < 0.001 |
| <$10,000 | 756 (9.9%) | 643 (14.1%) | 75 (3.1%) | -- |
| $10,000 to $49,999 | 2,229 (29.2%) | 1,548 (34.0%) | 482 (20.2%) | -- |
| $50,000 to $89,999 | 1,639 (21.5%) | 867 (19.0%) | 628 (26.3%) | -- |
| $90,000 to $149,999 | 969 (12.7%) | 350 (7.7%) | 516 (21.6%) | -- |
| ≥$150,000 | 355 (4.7%) | 85 (1.9%) | 232 (9.7%) | -- |
SAPPHIRE denotes the Study of Asthma-related Phenotypes and Pharmacogenomic Interactions by Race-Ethnicity; SD, standard deviation; and BMI, body mass index.
P-values compared the differences between individuals reporting African American and European American race.
Individuals grouped into the “other” category included those whose self-reported race is shown in Supplementary Table E7 but not included here, individuals affiliating with multiple race groups, and individuals whose race was unknown or unreported.
Genetic ancestry could be estimated in participants who had existing whole genome sequence data or genome-wide array data; this included 4,150 African American participants and 1,145 European American participants.
Participant-reported total pre-tax household income in the preceding year.