Table. Population Characteristics.
| Participants | All (N = 365) | Girls (n = 184) | Boys (n = 181) |
|---|---|---|---|
| Age of child at visit 1, mean (SD), y | 4.78 (0.52) | 4.77 (0.51) | 4.79 (0.53) |
| Age of child at visit 2, mean (SD), y | 6.71 (0.54) | 6.68 (0.54) | 6.73 (0.55) |
| Gestational age, mean (SD), mo | 38.4 (1.60) | 38.5 (1.55) | 38.3 (1.65) |
| Birth weight, mean (SD), kg | 3.07 (0.42) | 2.99 (0.41) | 3.15 (0.42) |
| HbA1c level at visit 1, mean (SD), % of total hemoglobina | 5.22 (0.39) | 5.24 (0.35) | 5.19 (0.43) |
| HbA1c level at visit 2, mean (SD), % of total hemoglobina | 5.38 (0.31) | 5.39 (0.27) | 5.36 (0.34) |
| Change in HbA1c level between visits, mean (SD), % of total hemoglobina | 0.16 (0.47) | 0.15 (0.41) | 0.17 (0.52) |
| Mothers | |||
| Age at delivery, mean (SD), y | 27.7 (5.65) | 27.3 (5.65) | 28.1 (5.64) |
| Prepregnancy BMI, mean (SD), kg/m2 | 26.3 (4.1) | 26.2 (4.3) | 26.4 (3.9) |
| SES, No. (%) | |||
| Low | 200 (54.8) | 98 (53.3) | 102 (56.4) |
| Medium | 131 (35.9) | 67 (36.4) | 64 (35.4) |
| High | 34 (9.3) | 19 (10.3) | 15 (8.3) |
| Education, No. (%) | |||
| Less than high school | 145 (39.7) | 67 (36.4) | 78 (43.1) |
| High school | 135 (37.0) | 74 (40.2) | 61 (33.7) |
| More than high school | 85 (23.3) | 43 (23.4) | 42 (23.2) |
| Any prenatal ETS exposure, No. (%) | 125 (37.7) | 86 (40.6) | 76 (36.9) |
| Season of last menstrual period | |||
| Cold-dry (November-February), No. (%) | 97 (26.6) | 47 (25.5) | 50 (27.6) |
| Warm-dry (March-April), No. (%) | 76 (20.8) | 40 (21.2) | 36 (19.9) |
| Rainy (May-October), No. (%) | 192 (52.6) | 97 (52.7) | 95 (52.5) |
| PM2.5 exposure, mean (SD), μg/m3 | 22.4 (2.7) | 22.4 (2.7) | 22.5 (2.6) |
| Preterm birth, No. (%) | 37 (10.1) | 19 (10.3) | 18 (9.9) |
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); ETS, environmental tobacco smoke; HbA1c, hemoglobin A1c; PM2.5, particulate matter with a diameter less than 2.5 μm; SES, socioeconomic status.
a
SI conversion factor: To convert HbA1c to proportion of total hemoglobin, multiply by 0.01.