Characteristics of ALSPAC mothers and offspring by categories of maternal 25(OH)D concentration pregnancy (% or mean and 95% CI; the column marked ‘N’ denotes the number of participants in the analysis sample with available data for each variable)
| N | 25(OH)D<25 nmol/L | 25(OH) D=25–49.9 nmol/L | 25(OH)D=50–75 nmol/L | 25(OH)D>75 nmol/L | p Value | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Maternal characteristics | ||||||||||
| Maternal age at delivery | 4031 | 27.5 | (26.7 to 28.2) | 28.6 | (28.3 to 28.8) | 28.8 | (28.6 to 29.1) | 29.4 | (29.2 to 29.6) | <0.001 |
| % Parity | 4109 | |||||||||
| 0 | 55.8 | 47.0 | 45.9 | 42.1 | 0.001 | |||||
| 1 | 32.7 | 34.4 | 34.2 | 38.4 | 0.02 | |||||
| 2 | 9.5 | 13.3 | 15.0 | 14.4 | 0.15 | |||||
| 3 | 2.0 | 3.2 | 4.0 | 4.5 | 0.05 | |||||
| 4 or 5 | 0.0 | 2.0 | 0.9 | 0.6 | 0.02 | |||||
| % Non-white European ethnicity | 4109 | 8.5 | 2.5 | 1.2 | 0.9 | <0.001 | ||||
| % Socioeconomic position | 4109 | |||||||||
| I/II | 51.9 | 56.3 | 59.6 | 61.7 | <0.001 | |||||
| III (non-manual) | 28.2 | 26.2 | 25.7 | 24.0 | 0.35 | |||||
| III (manual) | 14.8 | 12.8 | 10.6 | 10.7 | 0.10 | |||||
| IV/V | 5.2 | 4.8 | 4.2 | 3.7 | 0.22 | |||||
| Maternal education (% attended university) | 3868 | 12.1 | 14.9 | 15.1 | 16.7 | 0.09 | ||||
| Pre-pregnancy BMI | 3620 | 22.7 | (22.1 to 23.3) | 22.9 | (22.7 to 23.1) | 22.9 | (22.7 to 23.1) | 22.7 | (22.5 to 22.9) | 0.20 |
| Maternal smoking (%) | 4109 | |||||||||
| Never | 72.5 | 75.0 | 80.7 | 83.4 | <0.001 | |||||
| Before or during first trimester | 4.0 | 6.7 | 5.7 | 5.4 | 0.44 | |||||
| Throughout pregnancy | 23.5 | 18.3 | 13.6 | 11.3 | <0.001 | |||||
| Maternal physical activity in pregnancy (MET)* | 3268 | 9.9 | (8.2 to 12.0) | 11.3 | (10.5 to 12.1) | 12.0 | (11.2 to 12.8) | 12.6 | (11.9 to 13.4) | 0.003 |
| % Gestational hypertension | 3947 | 15.5 | 14.4 | 15.3 | 13.0 | 0.23 | ||||
| % Pre-eclampsia | 4013 | 2.6 | 1.8 | 1.4 | 1.6 | 0.42 | ||||
| % Gestational diabetes | 3951 | 0.0 | 0.7 | 0.8 | 0.5 | 0.98 | ||||
| % Glycosuria in pregnancy | 4109 | 2.5 | 3.2 | 2.8 | 2.4 | 0.31 | ||||
| Offspring characteristics | ||||||||||
| % male | 4109 | 54.4 | 49.5 | 51.9 | 52.2 | 0.39 | ||||
| Gestational age at 25(OH)D sampling (weeks) | 4109 | 24.0 | (22.3 to 25.7) | 23.4 | (22.8 to 24.0) | 23.7 | (23.1 to 24.3) | 25.7 | (25.1 to 26.2) | <0.001 |
| Birth weight (kg) | 3982 | 3.3 | (3.2 to 3.4) | 3.4 | (3.4 to 3.5) | 3.4 | (3.4 to 3.5) | 3.5 | (3.5 to 3.5) | <0.001 |
| Age at year 9.9 assessment (years) | 3566 | 9.94 | (9.89 to 10.00) | 9.87 | (9.85 to 9.89) | 9.84 | (9.82 to 9.86) | 9.86 | (9.85 to 9.88) | 0.16 |
| Age at year 15.4 assessment (years) | 2521 | 15.51 | (15.44 to 15.57) | 15.45 | (15.42 to 15.47) | 15.44 | (15.42 to 15.46) | 15.44 | (15.42 to 15.46) | 0.21 |
| BMI at year 9.9 assessment (kg/m2) | 3525 | 17.6 | (17.1 to 18.0) | 17.7 | (17.5 to 17.8) | 17.6 | (17.4 to 17.8) | 17.7 | (17.5 to 17.8) | 0.87 |
| BMI at year 15.4 assessment (kg/m2) | 2497 | 21.4 | (20.7 to 22.1) | 21.3 | (21.1 to 21.6) | 21.3 | (21.1 to 21.6) | 21.2 | (20.9 to 21.4) | 0.27 |
| Childhood 25(OH)D (nmol/L) | 4099 | 22.9 | (21.4 to 24.3) | 24.4 | (23.8 to 24.9) | 25.3 | (24.8 to 25.9) | 26.6 | (26.1 to 27.0) | <0.001 |
| Year 9.9 risk factors | ||||||||||
| SBP (mm Hg) | 3525 | 102.9 | (101.4 to 104.5) | 102.9 | (102.3 to 103.5) | 102.5 | (101.9 to 103.0) | 102.3 | (101.8 to 102.8) | 0.10 |
| DBP (mm Hg) | 3527 | 57.6 | (56.5 to 58.7) | 57.7 | (57.3 to 58.1) | 57.3 | (56.9 to 57.6) | 57.2 | (56.8 to 57.5) | 0.05 |
| Triglycerides (mmol/L)† | 2770 | 0.99 | (0.91 to 1.08) | 1.05 | (1.02 to 1.08) | 1.03 | (1.00 to 1.06) | 1.03 | (1.00 to 1.06) | 0.80 |
| LDL-C (mmol/L) | 2770 | 2.39 | (2.28 to 2.51) | 2.37 | (2.32 to 2.41) | 2.32 | (2.28 to 2.36) | 2.31 | (2.28 to 2.35) | 0.05 |
| HDL-C (mmol/L) | 2770 | 1.38 | (1.32 to 1.44) | 1.38 | (1.36 to 1.40) | 1.41 | (1.39 to 1.43) | 1.41 | (1.39 to 1.43) | 0.02 |
| Apo-A1 (mg/dL) | 2770 | 1.33 | (1.29 to 1.37) | 1.35 | (1.34 to 1.37) | 1.37 | (1.35 to 1.38) | 1.37 | (1.35 to 1.38) | 0.04 |
| Apo-B (mg/dL) | 2770 | 0.61 | (0.58 to 0.63) | 0.60 | (0.59 to 0.61) | 0.59 | (0.58 to 0.59) | 0.58 | (0.57 to 0.59) | 0.002 |
| CRP (mg/L)† | 2388 | 0.26 | (0.21 to 0.33) | 0.29 | (0.27 to 0.31) | 0.26 | (0.24 to 0.28) | 0.26 | (0.24 to 0.28) | 0.10 |
| IL6 (pg/mL)† | 2760 | 0.86 | (0.73 to 1.01) | 0.88 | (0.83 to 0.94) | 0.83 | (0.78 to 0.88) | 0.82 | (0.78 to 0.87) | 0.12 |
| Year 15.4 risk factors | ||||||||||
| SBP (mm Hg) | 2388 | 122.6 | (120.3 to 125.0) | 122.7 | (121.8 to 123.5) | 122.7 | (122.0 to 123.5) | 123.5 | (122.7 to 124.2) | 0.15 |
| DBP (mm Hg) | 2388 | 67.5 | (65.7 to 69.4) | 67.5 | (66.8 to 68.1) | 67.2 | (66.6 to 67.8) | 67.7 | (67.2 to 68.3) | 0.55 |
| Triglycerides (mmol/L)† | 1760 | 0.77 | (0.71 to 0.85) | 0.77 | (0.75 to 0.80) | 0.77 | (0.75 to 0.79) | 0.76 | (0.74 to 0.78) | 0.33 |
| LDL-C (mmol/L) | 1760 | 2.16 | (2.02 to 2.29) | 2.11 | (2.06 to 2.16) | 2.08 | (2.03 to 2.12) | 2.07 | (2.02 to 2.11) | 0.12 |
| HDL-C (mmol/L) | 1760 | 1.25 | (1.17 to 1.32) | 1.27 | (1.24 to 1.30) | 1.27 | (1.25 to 1.30) | 1.30 | (1.27 to 1.32) | 0.07 |
| Glucose (mmol/L) | 1760 | 5.22 | (5.12 to 5.32) | 5.17 | (5.13 to 5.20) | 5.21 | (5.17 to 5.24) | 5.21 | (5.18 to 5.24) | 0.15 |
| Insulin (IU/L)† | 1757 | 9.18 | (8.13 to 10.35) | 8.77 | (8.40 to 9.17) | 8.94 | (8.58 to 9.31) | 8.81 | (8.49 to 9.14) | 0.83 |
| CRP (mg/L)† | 1760 | 0.64 | (0.49 to 0.84) | 0.52 | (0.47 to 0.57) | 0.52 | (0.48 to 0.57) | 0.44 | (0.41 to 0.48) | 0.001 |
*MET, metabolic equivalent.
†Geometric means.
25(OH)D, Total 25-hydroxyvitamin D; ALSPAC, Avon Longitudinal Study of Parents and Children; Apo-A1, apolipoprotein-A1; Apo-B, apolipoprotein-B; BMI, body mass index; CRP, C reactive protein; DBP, diastolic blood pressure; HDL-C, high density lipoprotein cholesterol; IL6, interleukin 6; LDL-C, low density lipoprotein cholesterol; SBP, systolic blood pressure.