Characteristics of the study population (N=19 779) by birth weight
| Characteristics | <2.0 kg n=3998 | 2.0–3.0 kg n=11 510 | >3.0 kg n=4271 | P value |
| Age (years), mean (SD) | 57.37 (9.6) | 55.07 (8.8) | 54.70 (8.9) | <0.001 |
| Male sex, n (%) | 1307 (32.7) | 3504 (30.4) | 2042 (47.8) | <0.001 |
| Education, n (%) | <0.001 | |||
| <8 years | 1251 (31.3) | 2850 (24.8) | 1009 (23.6) | |
| ≥8 years | 2747 (68.7) | 8660 (75.2) | 3262 (76.4) | |
| Marital status, n (%) | <0.001 | |||
| Married/cohabited | 2911 (72.8) | 8749 (76.0) | 3298 (77.2) | |
| Single | 1087 (27.2) | 2761 (24.0) | 973 (22.8) | |
| Zygosity, n (%) | <0.001 | |||
| Monozygosity | 1027 (25.7) | 2647 (23.0) | 685 (16.0) | |
| Dizygosity | 2384 (59.6) | 7436 (64.6) | 3021 (70.7) | |
| Undetermined | 587 (14.7) | 1427 (12.4) | 565 (13.2) | |
| BMI, mean (SD) | 25.02 (3.8) | 24.67 (3.5) | 25.13 (3.5) | <0.001 |
| BMI, n (%) | <0.001 | |||
| <18.5 (underweight) | 71 (1.8) | 167 (1.4) | 46 (1.1) | |
| 18.5–24.9 (normal weight) | 2108 (52.7) | 6600 (57.3) | 2218 (52.0) | |
| 25.0–29.9 (overweight) | 1439 (36.0) | 3874 (33.7) | 1623 (38.0) | |
| ≥30 (obese) | 380 (9.5) | 869 (7.6) | 384 (9.0) | |
| Smoking status, n (%) | <0.001 | |||
| Never smoked | 2049 (51.2) | 5825 (50.6) | 1932 (45.2) | |
| Former/current smoker | 1949 (48.8) | 5685 (49.4) | 2339 (54.8) | |
| Alcohol consumption, n (%) | <0.001 | |||
| No/mild drinking | 3735 (93.4) | 10 746 (93.4) | 3884 (90.9) | |
| Heavy drinking | 263 (6.6) | 764 (6.6) | 387 (9.1) | |
| Active physical exercise, n (%) | 0.008 | |||
| No | 2092 (52.3) | 5736 (49.8) | 2101 (49.2) | |
| Yes | 1905 (48.2) | 5774 (50.2) | 2170 (50.8) | |
| Hypertension, n (%) | 1299 (33.5) | 2954 (25.7) | 1023 (24.0) | <0.001 |
Data are presented as means±SD or number (%).
BMI, body mass index.