TABLE 1.
Description of the gestational and perinatal covariates for each group of pulmonary function trajectories: the 1993 Pelotas Birth Cohort, Brazil
| FEV1 | FVC | FEV1/ FVC | ||||||||||
|
Low N=435 |
Average N=1776 |
High N=706 |
p-value |
Low N=635 |
Average N=1657 |
High N=625 |
p-value |
Low N=249 |
Average N=1279 |
High N=1389 |
p-value | |
| Income (minimum wages) ¶# | 4.56±0.34 | 4.04±0.12 | 4.66±0.22 | 0.023 | 4.04±0.21 | 4.27±0.13 | 4.48±0.24 | 0.381 | 4.54±0.42 | 4.20±0.15 | 4.27±0.15 | 0.964 |
| Male sex % | 245 (56.3) | 809 (45.6) | 381 (54.0) | <0.001 | 348 (54.8) | 760 (45.9) | 327 (52.3) | <0.001 | 153 (61.4) | 710 (55.5) | 572 (41.2) | <0.001 |
| Birth weight g¶ | 3164.8±25.4 | 3175.8±12.4 | 3232.0±19.8 | 0.029 | 3132.3±19.4 | 3195.1±13.0 | 3224.8±21.6 | 0.005 | 3240.1±37.3 | 3204.3±14.7 | 3163.3±13.7 | 0.034 |
| Prematurity (%) | 51 (13.4) | 160 (10.1) | 65 (10.2) | 0.151 | 71 (13.0) | 141 (9.5) | 64 (11.2) | 0.072 | 30 (13.1) | 106 (9.3) | 140 (11.4) | 0.144 |
| Pregestational BMI kg·m−2 ¶ | 22.4±0.2 | 22.8±0.1 | 23.3±0.1 | <0.001 | 22.1±0.14 | 23.0±0.1 | 23.3±0.15 | <0.001 | 23.0±0.25 | 23.1±0.10 | 22.6±0.10 | 0.006 |
| Smoking in pregnancy % | ||||||||||||
| 1° trimester | 133 (30.6) | 499 (28.1) | 220 (31.0) | 0.252 | 177 (27.9) | 470 (28.4) | 205 (32.8) | 0.081 | 94 (37.7) | 384 (30.0) | 374 (26.9) | 0.002 |
| 2° trimester | 126 (29.0) | 474 (26.7) | 206 (29.2) | 0.364 | 168 (26.4) | 446 (26.9) | 192 (30.7) | 0.146 | 82 (32.9) | 360 (28.1) | 364 (26.2) | 0.079 |
| 3° trimester | 120 (27.6) | 469 (26.4) | 203 (28.7) | 0.483 | 156 (24.6) | 447 (27.0) | 189 (30.2) | 0.075 | 82 (32.9) | 353 (27.6) | 357 (25.7) | 0.055 |
| Father's smoke % | 182 (41.8) | 815 (45.9) | 309 (43.9) | 0.259 | 283 (44.5) | 750 (45.3) | 273 (43.7) | 0.789 | 97 (38.9) | 568 (44.4) | 641 (46.1) | 0.103 |
| Alcohol in pregnancy % | 17 (3.9) | 93 (5.2) | 40 (5.7) | 0.409 | 28 (4.4) | 88 (5.3) | 34 (5.4) | 0.635 | 14 (5.6) | 60 (4.7) | 76 (5.5) | 0.619 |
Data are presented as mean±sd or n (%), unless otherwise stated. p-values were obtained by the Chi-squared test, unless otherwise stated. FEV1: forced expiratory volume in 1 s; FVC: forced vital capacity; BMI: body mass index. #: family income in minimum wages per month in Brazilian currency (a minimum wage equivalent to approximately US$84). ¶: p-value obtained by ANOVA. N: absolute frequencies of individuals per pulmonary function (PF) trajectories based on the total sample (2197); n: absolute frequencies of the exposure covariables per PF trajectory.