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Table 1 Characteristics of participants (n = 1115)a

From: Epigenetic age acceleration and cardiovascular outcomes in school-age children: The Generation R Study

Maternal characteristics  
Age, y 32.0 (4.0)
Educational level  
 No, primary, secondary, n (%) 353 (32.0)
 College or higher, n (%) 749 (68.0)
Pre-pregnancy body mass index, kg/m2 22.3 (18.5, 34.1)
Folic acid supplementation during pregnancy  
 No supplementation, n (%) 62 (6.8)
 Started before 10 weeks, n (%) 282 (31.2)
 Started preconception, n (%) 561 (62.0)
Smoking during pregnancy  
 Non-smoker or smoked until pregnancy was known, n (%) 900 (88.5)
 Smoked throughout pregnancy, n (%) 117 (11.5)
Pregnancy dating based on last menstrual period  
 No, n (%) 297 (26.6)
 Yes, n (%) 818 (73.4)
Self-reported hypertension  
 No, n (%) 971 (99.1)
 Yes, n (%) 9 (0.9)
Family history of cardiovascular diseaseb  
 No, n (%) 533 (54.2)
 Yes, n (%) 451 (45.8)
Birth characteristics  
Clinical gestational age, wk 40.2 (37.0, 42.4)
DNA methylation gestational age (Bohlin), wk 39.4 (37.2, 40.8)
Raw gestational age acceleration (Bohlin), wk − 0.90 (− 2.76, 0.92)
Residual gestational age acceleration (Bohlin), wk 0.03 (− 1.24, 1.09)
DNA methylation gestational age (Knight), wk 36.5 (32.4, 39.3)
Raw gestational age acceleration (Knight), wk − 3.70 (− 7.44, − 1.07)
Residual gestational age acceleration (Knight), wk 0.15 (− 3.34, 2.63)
Sex  
 Boy, n (%) 544 (48.8)
 Girl, n (%) 571 (51.2)
Childhood characteristics  
At 6 y  
 Age at visitc, y 6.0 (5.7, 7.0)
 DNA methylation age (Skin and blood), y 5.6 (4.3, 7.9)
 Raw age acceleration (Skin and blood), y − 0.39 (1.7, 1.7)
 Residual age acceleration (Skin and blood), y − 0.03 (− 1.3, 2.1)
 Blood pressure, mmHg  
  Systolic 102 (7.7)
  Diastolic 60 (6.3)
At 10 y  
 Age at visit, y  
  Children with DNA methylation data at birth 9.8 (9.3, 10.5)
  Children with DNA methylation data at 10 yd 9.8 (9.2, 10.3)
 DNA methylation age (Skin and blood), y 8.5 (6.7, 11.5)
 Raw age acceleration (Skin and blood), y − 1.2 (− 3.0, 1.8)
 Residual age acceleration (Skin and blood), y − 0.10 (− 1.9, 2.8)
 Blood pressure, mmHg  
  Systolic 103 (7.7)
  Diastolic 58 (6.2)
 Common carotid artery intima-media thickness, mm 0.45 (0.04)
 Common carotid artery distensibilitye, kPa−1*10–3 56.0 (37.3, 85.0)
  1. wk, week; y, year
  2. aFor the analyses based on Bohlin’s epigenetic clock, we excluded 11 newborns with missing values for some of the required CpGs, leaving 1104 children for analysis in the full population and 295 children in the subgroup with optimal pregnancy dating. Values are based on observed, not imputed data and are mean (SD) or median (95% range) for continuous variables and numbers (%) for categorical variables. Missing data: maternal education: n = 13; maternal body mass index: n = 170; folic acid supplementation: n = 210; maternal smoking: n = 98
  3. bWe obtained this information from maternal questionnaires sent out during pregnancy. Family history of cardiovascular disease was defined as a first-degree relative with any of hypertension, myocardial infarction below the age of 65, cerebrovascular accident
  4. cOf these 470 children, 12 children were not included in the analyses at birth, as they had no cord blood DNA methylation measured
  5. dOf these 449 children, 14 children were not included in the analyses at birth, as they had no cord blood DNA methylation measured
  6. eIndicate values before natural-log transformation