Associations of Existing Diabetes, Gestational Diabetes, and Glycosuria with Offspring IQ and Educational Attainment: The Avon Longitudinal Study of Parents and Children

Table 1

Characteristics (mean (SD) or %) of mothers and offspring included in at least one analysis 𝑁=8,515.

Characteristic	No diabetes/Glycosuria	Preexisting diabetes	Gestational diabetes	Glycosuria	𝑃 value for difference between groups
	(𝑁=8,192)	(𝑁=26)	(𝑁=33)	(𝑁=264)
Maternal
Manual social class, %	17.7	19.2	21.2	22.4	0.28
University education, %	13.7	15.4	9.1	9.5	0.18
Prepregnancy BMI, kg/m^2	22.9 (3.8)	24.3 (4.5)	25.7 (5.7)	23.7 (4.3)	<0.001
Age at delivery, years	28.6 (4.7)	29.2 (3.7)	29.6 (4.6)	28.4 (4.9)	<0.001
No smoking in pregnancy, %	77.9	84.6	90.9	79.2	0.18
Parity ≥1, %	55.1	50.0	60.6	52.3	0.68
Caesarean section, %	7.6	0.3	0.7	3.1	0.88
No breastfeeding, %	25.1	15.4	27.8	24.7	0.85
Offspring
Males, %	50.8	50.0	69.7	44.7	0.03
Birth weight (grams)	3480 (467)	3367 (649)	3889 (520)	3574 (484)	<0.001
Gestational age (weeks)	39.8 (1.3)	38.5 (1.3)	39.0 (1.3)	39.8 (1.4)	<0.001
School Entry Assessment score 𝑁=6,032	13.1 (3.1)	12.7 (4.2)	13.0 (2.8)	12.9 (3.1)	0.65
Total IQ 𝑁=5,282	105.3 (16.3)	103.2 (17.7)	98.7 (19.9)	103.2 (15.7)	0.09
Verbal IQ 𝑁=5,307	108.2 (16.6)	108.0 (19.6)	101.0 (21.2)	106.1 (16.0)	0.07
Performance IQ 𝑁=5,298	100.5 (17.0)	95.9 (14.4)	97.3 (21.0)	99.1 (16.6)	0.37
High achievement: 5+ GCSEs C-A, %  𝑁=7,615	56.9	53.9	51.6	51.7	0.40
Low achievement: 0 GCSEs C-A, %  𝑁=7,615	14.0	26.9	16.1	14.6	0.37