Table 1.
Baseline characteristics of the study participants according to quintiles of general intelligence test scores
| Q1 | Q2 | Q3 | Q4 | Q5 | Total | p value for linear trend | |
|---|---|---|---|---|---|---|---|
| N of participants | 445,492 | 480,543 | 439,974 | 471,624 | 439,555 | 2,277,188 | |
| Female % | 31 | 43 | 44 | 44 | 40 | 40 | |
| Age ± SD | 17.4 ± 0.5 | 17.3 ± 0.4 | 17.3 ± 0.4 | 17.3 ± 0.4 | 17.3 ± 0.4 | 17.3 ± 0.4 | 0.158 |
| BMI ± SD (kg/m2) | 21.7 ± 3.6 | 21.7 ± 3.4 | 21.7 ± 3.3 | 21.6 ± 3.2 | 21.6 ± 3.1 | 21.6 ± 3.4 | 0.071 |
| Underweight % | 8.7 | 6.9 | 6.0 | 5.7 | 5.4 | 6.5 | 0.024 |
| Overweight % | 8.9 | 8.8 | 8.6 | 8.4 | 7.8 | 8.5 | 0.016 |
| Obese % | 4.9 | 4.0 | 3.5 | 3.3 | 3.0 | 3.7 | 0.011 |
| Height ± SD (males) | 171.8 ± 6.8 | 173.1 ± 6.8 | 173.6 ± 6.7 | 174.4 ± 6.7 | 175.1 ± 6.7 | 173.6 ± 6.8 | 0.001 |
| Height ± SD (females) | 160.9 ± 6.2 | 161.7 ± 6.1 | 162.0 ± 6.1 | 162.6 ± 6.0 | 163.1 ± 6.0 | 162.1 ± 6.1 | 0.001 |
| Completed high school education (%) | 56.9 | 76.3 | 82.1 | 91.0 | 96.0 | 80.5 | < 0.001 |
| Low SES % | 33 | 26 | 23 | 20 | 19 | 24 | 0.001 |
| Unimpaired health | 77.6 | 80.3 | 81.9 | 82.6 | 80.3 | 81.2 | 0.069 |
| Country of origin (%) | |||||||
| Israel | 4.6 | 5.0 | 5.7 | 6.4 | 7.6 | 5.8 | 0.003 |
| USSR | 9.0 | 10.9 | 11.8 | 14.7 | 16.1 | 12.5 | 0.001 |
| Asia | 30.6 | 29.5 | 26.6 | 21.9 | 16.0 | 25.0 | 0.007 |
| Africa | 38.1 | 30.8 | 24.5 | 17.8 | 11.8 | 24.7 | < 0.001 |
| Europe | 13.7 | 22.6 | 30.9 | 39.0 | 48.4 | 30.8 | < 0.001 |
| Ethiopia | 4.0 | 1.3 | 0.5 | 0.2 | 0.1 | 1.2 | 0.057* |
| Systolic/diastolic BP ± SD (mmHg) | 116.5 ± 12.2/71.8 ± 8.3 | 115.9 ± 12.2/71.8 ± 8.2 | 116.3 ± 12.3/71.6 ± 8.2 | 116.3 ± 12.2/71.7 ± 8.2 | 117.1 ± 12.3/71.7 ± 8.2 | 116.4 ± 12.2/71.7 ± 8.2 | 0.110/0.319 |
| Follow-up (mean ± SD) (years) | 19.0 ± 9.8 | 19.2 ± 8.9 | 20.0 ± 10.2 | 19.0 ± 9.7 | 18.9 ± 10.3 | 19.2 ± 9.8 | 0.821 |
| Median follow-up (25th; 75th) (years) | 18.8 (10.3, 28.7) | 18.9 (13.2, 27.0) | 19.7 (10.6, 32.0) | 18.9 (11.0, 29.3) | 19.9 (9.3, 30.1) | 19.2 (10.7, 29.5) | 0.759 |
| Cumulative follow-up (person-years) | 8,064,856 | 8,840,363 | 8,453,920 | 8,577,783 | 7,979,682 | 41,916,603 | 0.414 |
| Age at end of follow-up (± SD) | 37.0 ± 12.1 | 37.0 ± 11.0 | 38.4 ± 12.7 | 36.9 ± 11.9 | 36.9 ± 12.5 | 37.2 ± 12.0 | 0.907 |
* Exponential trend p < 0.001