Association between weight groups of the children at 5 years of age and early life predictors (2a), early childhood and current health and habits of the children (2b) and current sociodemographic and health characteristics of parents and siblings (2c). For variables with significant associations, pairwise bivariate analyses with normal weight as reference was performed
| Characteristics (mean (SD) or %) | Valid n | All (n=1088) | Underweight (n=85) | Normal weight (n=850) | Overweight (n=115) | Obese (n=38) | p¶ |
| 2a. Early life predictors | |||||||
| Girls | 1088 | 52.5 | 51.8 | 51.4 | 59.1 | 57.9 | 0.41 |
| Birth weight (kg) | 1069 | 3.56 (0.61) | 3.29 (0.65)* | 3.58 (0.59) | 3.57 (0.66) | 3.72 (0.61) | <0.01 |
| Birth weight SDS | 1060 | −0.27 (1.35) | −0.87 (1.49)* | −0.23 (1.31) | −0.25 (1.44) | 0.07 (1.32) | <0.01 |
| Crown–heel length at birth (cm) | 963 | 50.54 (2.41) | 49.90 (2.67) | 50.62 (2.41) | 50.37 (2.29) | 50.73 (2.10) | 0.09 |
| Crown–heel length SDS at birth | 954 | −0.02 (1.17) | −0.33 (1.31) | 0.01 (1.16) | −0.10 (1.10) | 0.10 (0.97) | 0.10 |
| BMI SDS birth | 940 | −0.15 (0.99) | −0.64 (1.08)* | −0.13 (0.97) | −0.02 (0.97) | −0.01 (0.94) | <0.01 |
| Birth weight <2500 g | 1069 | 4.8 | 9.8 | 4.2 | 6.1 | 2.8 | |
| >4000 g | 22.3 | 12.2 | 22.7 | 22.8 | 33.3 | 0.06 | |
| Birth weight <10 percentile | 746 | 4.3 | 10.7 | 3.6 | 4.1 | 7.4 | 0.07 |
| Birth weight >90 percentile | 744 | 11.8 | 5.4 | 12.3 | 12.2 | 14.8 | 0.46 |
| Premature birth | 1088 | 6.8 | 10.6 | 6.6 | 7.0 | 2.6 | 0.39 |
| Exclusive breast feeding >4 months | 1003 | 72.8 | 80.9 | 73.9 | 65.6 | 51.7* | <0.01 |
| Mothers’ age at birth (years) | 1088 | 29.90 (4.78) | 29.16 (4.46) | 30.03 (4.73) | 30.26 (5.27) | 27.52 (4.57)* | <0.01 |
| Mothers’ height (cm) | 1025 | 167.80 (5.82) | 167.78 (6.48) | 168.01 (5.73) | 166.56 (5.67)* | 165.69 (6.23) | 0.01 |
| Prepregnancy BMI (kg/m2) | 673 | 24.15 (4.20) | 22.76 (3.22) | 23.91 (3.96) | 26.18 (4.85)* | 27.43 (5.43)* | <0.01 |
| Gestational weight gain, kg | 678 | 15.15 (5.56) | 14.82 (5.64) | 15.22 (5.53) | 15.10 (5.68) | 14.14 (6.30) | 0.81 |
| Gestational weight gain above recommended | 661 | 54.4 | 34.0 | 41.7 | 59.4* | 50.0 | 0.03 |
| Smoking at week 18 in pregnancy | 738 | 15.9 | 7.0 | 13.3 | 34.2* | 39.3* | <0.01 |
| 2b. Children’s early childhood and current health and habits | |||||||
| Current child height SDS | 1025 | 0.18 (1.03) | 0.10 (1.08) | 0.11 (1.00) | 0.55 (1.13)* | 0.77 (0.89)* | <0.01 |
| Current child BMI SDS | 1085 | 0.01 (1.03) | −1.91 (0.55)* | −0.10 (0.65) | 1.41 (0.27)* | 2.36 (0.44)* | <0.01 |
| Asthma medication† | 1058 | 11.6 | 9.8 | 11.0 | 14.7 | 21.1 | 0.18 |
| Antibiotics ≥3 times‡ | 1088 | 23.8 | 20.0 | 23.6 | 24.3 | 34.2 | 0.14 |
| Dental caries | 1079 | 20.0 | 18.8 | 18.7 | 25.9 | 34.2* | 0.04 |
| Combined physical activity score poorer than peers§ | 1073 | 5.1 | 5.9 | 3.8 | 8.0* | 24.3* | <0.01 |
| Kindergarten since 2 years old | 1033 | 92.1 | 91.5 | 92.7 | 90.6 | 82.4 | 0.16 |
| TV in the child’s bedroom | 1084 | 14.1 | 12.9 | 13.0 | 15.7 | 38.9* | <0.01 |
| Vegetables <5 times/week | 1071 | 50.6 | 56.5 | 50.6 | 44.2 | 56.8 | 0.31 |
| Fruits <5 times/week | 1078 | 19.5 | 21.2 | 20.2 | 11.3 | 24.3 | 0.12 |
| Sugar-sweetened beverages >1 time/week | 1077 | 31.2 | 29.4 | 31.6 | 29.8 | 29.7 | 0.95 |
| Sweets/snacks >1 time/week | 1079 | 42.7 | 34.5 | 43.4 | 45.1 | 37.8 | 0.38 |
| 2c. Sociodemographic factors and health characteristics of parents and siblings | |||||||
| Living in a municipality with >20 000 inhabitants | 1087 | 32.4 | 38.8 | 32.6 | 30.4 | 18.4 | 0.16 |
| Maternal education above high school | 1068 | 55.1 | 55.0 | 58.3 | 43.9* | 18.9* | <0.01 |
| Paternal education above high school | 1037 | 39.3 | 48.1 | 41.1 | 27.8* | 14.3* | <0.01 |
| Both parents education above high school | 1077 | 32.5 | 39.7 | 34.4 | 21.3* | 5.9* | <0.01 |
| Mother working (full-time/part-time, student) | 1069 | 91.8 | 91.5 | 92.5 | 90.3 | 81.1 | 0.09 |
| Father working (full-time/part-time, student) | 1046 | 95.2 | 95.1 | 96.0 | 92.9 | 84.8* | 0.02 |
| One or both parents from non-Western countries | 1088 | 2.7 | 3.5 | 2.1 | 3.5 | 10.5* | 0.01 |
| Living with one caretaker | 1073 | 13.0 | 9.8 | 12.0 | 17.5 | 29.7* | <0.01 |
| No siblings | 1065 | 9.1 | 3.6 | 9.0 | 16.8* | 2.9 | <0.01 |
| Mother smoking | 1088 | 19.0 | 14.1 | 16.6 | 32.2* | 44.7* | <0.01 |
| Current BMI mother (kg/m2) | 981 | 24.32 (3.85) | 23.06 (3.31) | 24.07 (3.66) | 26.03 (4.15)* | 27.52 (5.12)* | <0.01 |
| Current BMI father (kg/m2) | 924 | 26.38 (3.30) | 25.13 (2.72)* | 26.25 (3.16) | 27.57 (3.75)* | 28.89 (4.33)* | <0.01 |
| BMI SDS average for siblings | 630 | −0.21 (1.23) | −0.76 (1.26)* | −0.24 (1.20) | 0.26 (1.06)* | 0.55 (1.45)* | <0.01 |
| Mother currently obese | 980 | 9.1 | 6.5 | 7.2 | 16.8* | 34.3* | <0.01 |
| Father currently obese | 924 | 13.0 | 3.9* | 11.2 | 26.1* | 37.5* | <0.01 |
| Both parents currently obese | 891 | 2.7 | 1.4 | 2.0 | 3.4 | 19.4* | <0.01 |
*Post hoc pairwise testing by Dunnett's t-test (continuous variables) or χ2 (categorical) showed a significant difference (p≤0.05) compared with children of normal weight at 5 years of age; only when significant ANOVA or χ2 across groups.
†Steroids or other maintenance medications or medication for asthma attacks after 2 years of age.
‡Since birth irrespective of cause.
§Computed from the three dimensions of physical activity: frequency, intensity and endurance, each scored from 1 to 3 (better than peers, like peers and worse than peers), giving a total score of 3–9, where 9 meant poorer than peers in all three dimensions. The figure is the prevalence of children with a score of 6 or higher.
¶Analyses across weight groups, ANOVA for continuous variables, χ2 for categorical.
ANOVA, analysis of variance; BMI, body mass index; SDS, SD score.