Association of maternal BMI before pregnancy, weight gain during pregnancy, and other characteristics with risk of persistent positivity for multiple islet autoantibodies in children in the MIDIA study
| . | Affected . | Unaffected . | Unadjusted HR (95% CI) . | P . |
|---|---|---|---|---|
| n | 36 | 797 | ||
| Follow-up from birth (months) | 14.0 (4.5–31)* | 28.6 (3.2–86)* | NA | NA |
| Sex (female) | 21 (58) | 411 (48) | 1.40 (0.72–2.7) | 0.32 |
| Maternal BMI (kg/m2) | ||||
| <25 | 21 (58) | 540 (66) | 1.0 ref. | |
| 25–29.9 | 6 (17) | 186 (23) | 0.83 (0.33–2.05) | 0.68 |
| ≥30 | 9 (25) | 92 (11) | 2.48 (1.14–5.4) | 0.023 |
| Mean (interquartile range) | 26.2 (21.8–29.4) | 24.4 (21.3–26.2) | 1.07 (1.01–1.13) | 0.021 |
| Maternal weight gain (kg) | ||||
| <15 | 10 (28) | 414 (50) | 1.0 ref. | |
| ≥15 | 26 (72) | 405 (50) | 2.47 (1.19–5.1) | 0.015 |
| Mean (interquartile range) | 16.1 (13.5–19.0) | 14.6 (11.0–18.0) | 1.04 (0.99–1.10) | 0.14 |
| Child's weight gain 3–12 months (kg) | 3.82 (3.3–4.2) | 3.63 (3.1–4.1) | 1.33 (0.94–1.89) | 0.11 |
| Child's length gain 3–12 months (cm) | 14.75 (14–15) | 14.67 (13–16) | 1.03 (0.89–1.20) | 0.66 |
| Age at weaning (months) | 10.25 (8–12) | 9.50 (6–12) | 1.00 (0.94–1.06) | 0.99 |
| Duration exclusive breastfeeding (months) | 3.52 (2.25–4.5) | 3.29 (1.25–4.5) | 1.05 (0.89–1.24) | 0.56 |
| First-degree type 1 diabetic relative | 11 (31) | 52 (6.1) | 5.92 (2.91–12.0) | <0.001 |
| Maternal pregestational type 1 diabetes | 3 (8.3) | 19 (2.2) | 3.67 (1.12–12.0) | 0.031 |
| Maternal gestational diabetes† | 0 (0) | 12 (1.4) | NA | NA |
| Maternal age at birth (years) | 31.1 (28.0–33.5) | 30.7 (28.0–34.0) | 1.01 (0.94–1.09) | 0.71 |
| Smoking in pregnancy | 3 (8.3) | 160 (19) | 0.41 (0.12–1.32) | 0.14 |
| Maternal education | ||||
| ≤3 years high school | 13 (36) | 329 (39) | 1.0 ref. | Global |
| ≤4 years university | 16 (44) | 343 (41) | 1.20 (0.58–2.5) | 0.89 |
| >4 years university | 7 (19) | 171 (20) | 1.00 (0.40–2.5) | |
| Child is first born vs. later born | 8 (22) | 300 (35) | 0.54 (0.25–1.18) | 0.12 |
| . | Affected . | Unaffected . | Unadjusted HR (95% CI) . | P . |
|---|---|---|---|---|
| n | 36 | 797 | ||
| Follow-up from birth (months) | 14.0 (4.5–31)* | 28.6 (3.2–86)* | NA | NA |
| Sex (female) | 21 (58) | 411 (48) | 1.40 (0.72–2.7) | 0.32 |
| Maternal BMI (kg/m2) | ||||
| <25 | 21 (58) | 540 (66) | 1.0 ref. | |
| 25–29.9 | 6 (17) | 186 (23) | 0.83 (0.33–2.05) | 0.68 |
| ≥30 | 9 (25) | 92 (11) | 2.48 (1.14–5.4) | 0.023 |
| Mean (interquartile range) | 26.2 (21.8–29.4) | 24.4 (21.3–26.2) | 1.07 (1.01–1.13) | 0.021 |
| Maternal weight gain (kg) | ||||
| <15 | 10 (28) | 414 (50) | 1.0 ref. | |
| ≥15 | 26 (72) | 405 (50) | 2.47 (1.19–5.1) | 0.015 |
| Mean (interquartile range) | 16.1 (13.5–19.0) | 14.6 (11.0–18.0) | 1.04 (0.99–1.10) | 0.14 |
| Child's weight gain 3–12 months (kg) | 3.82 (3.3–4.2) | 3.63 (3.1–4.1) | 1.33 (0.94–1.89) | 0.11 |
| Child's length gain 3–12 months (cm) | 14.75 (14–15) | 14.67 (13–16) | 1.03 (0.89–1.20) | 0.66 |
| Age at weaning (months) | 10.25 (8–12) | 9.50 (6–12) | 1.00 (0.94–1.06) | 0.99 |
| Duration exclusive breastfeeding (months) | 3.52 (2.25–4.5) | 3.29 (1.25–4.5) | 1.05 (0.89–1.24) | 0.56 |
| First-degree type 1 diabetic relative | 11 (31) | 52 (6.1) | 5.92 (2.91–12.0) | <0.001 |
| Maternal pregestational type 1 diabetes | 3 (8.3) | 19 (2.2) | 3.67 (1.12–12.0) | 0.031 |
| Maternal gestational diabetes† | 0 (0) | 12 (1.4) | NA | NA |
| Maternal age at birth (years) | 31.1 (28.0–33.5) | 30.7 (28.0–34.0) | 1.01 (0.94–1.09) | 0.71 |
| Smoking in pregnancy | 3 (8.3) | 160 (19) | 0.41 (0.12–1.32) | 0.14 |
| Maternal education | ||||
| ≤3 years high school | 13 (36) | 329 (39) | 1.0 ref. | Global |
| ≤4 years university | 16 (44) | 343 (41) | 1.20 (0.58–2.5) | 0.89 |
| >4 years university | 7 (19) | 171 (20) | 1.00 (0.40–2.5) | |
| Child is first born vs. later born | 8 (22) | 300 (35) | 0.54 (0.25–1.18) | 0.12 |
Data are n (%) for categorical variables, mean (interquartile range) for continuous variables, and *mean (range) where indicated. All HRs for continuous variables are per unit increment (1 kg/m2 or 1 kg wt gain). Maternal BMI before pregnancy was missing for 31 children, maternal weight gain was missing for 30 children, gestational diabetes was missing for 47 children, maternal age at birth was missing for 11 children, smoking in pregnancy was missing for 5 children, maternal education was missing for 6 children, duration of exclusive breast feeding was missing for 16 children, weight of the child at 3 months was missing for 69 children, length of the child at 3 months was missing for 74 children, weight of the child at 12 months was missing for 144 children, and length of the child at 12 months was missing for 149 children.
†None of the mothers reported type 2 diabetes. The variables used in the regression model for the case group had none missing. NA, not applicable.