TABLE 1—
Characteristics of Participants at Baseline and During Follow-Up, by Body Mass Index Trajectory Groups: Guangdong, China, 2006–2016
| Trajectory Group |
|||||
| Variables | Overall | Low | Middlea | High | Very High |
| Number of participants, no. (%) | 9286 | 3 725 (40.1) | 3 754 (40.4) | 1 480 (15.9) | 327 (3.5) |
| Male, no. (%) | 4 650 (50.1) | 1 985 (53.3)** | 1 776 (47.3) | 694 (46.9)** | 195 (59.6)* |
| Urban living, no. (%) | 4 612 (49.7) | 1 698 (45.6)** | 1 894 (50.5) | 846 (57.2)** | 174 (53.2)** |
| Baseline | |||||
| Age, y, mean ±SD | 8.2 ±0.9 | 8.2 ±0.9 | 8.2 ±0.9 | 8.2 ±0.9 | 8.2 ±0.9 |
| BMI, kg/m2, mean ±SD | 15.3 ±2.0 | 14.1 ±0.9** | 15.4 ±1.2 | 17.2 ±1.8** | 20.3 ±2.7** |
| SBP, mm Hg, mean ±SD | 104.6 ±5.5 | 103.9 ±5.5** | 104.7 ±5.4 | 105.6 ±5.4** | 106.5 ±5.4** |
| DBP, mm Hg, mean ±SD | 66.6 ±4.7 | 66.3 ±4.7 | 66.6 ±4.7 | 67.0 ±4.7** | 67.1 ±5.0 |
| Thinness,b no. (%) | 673 (7.2) | 650 (17.5)** | 23 (0.6) | . . . | . . . |
| Stunting,b no. (%) | 539 (5.8) | 318 (8.5)** | 164 (4.4) | 45 (3.0)** | 12 (3.7)* |
| Overweight,b no. (%) | 994 (10.7) | 6 (0.2)** | 126 (3.4) | 570 (38.5)** | 292 (89.3)** |
| Follow-up | |||||
| Years, mean ±SD | 9.0 ±1.0 | 9.1 ±1.0 | 9.0 ±1.0 | 9.0 ±1.0 | 9.1 ±1.1 |
| Average incident HBP/100 person-y (95% CI) | 6.51 (6.36, 6.65) | 5.92 (5.70, 6.14)** | 6.51 (6.28, 6.75) | 7.66 (7.25, 8.08)** | 8.67 (7.76, 9.68)** |
| Total measurement with detected HBP, no. (%) | 18 440 (23.5) | 6 017 (19.3)** | 7 348 (23.1) | 3 840 (30.4)** | 1 235 (44.5)** |
| HBP prevalence at endpoint, no. (%) | 1 569 (16.9) | 452 (12.1)** | 620 (16.5) | 353 (23.9)** | 144 (44.0)** |
| Overweight at endpoint, no. (%) | 770 (8.3) | . . . | 37 (1.0) | 429 (29.0)** | 304 (93.0)** |
Note. BMI = body mass index; CI = confidence interval; DBP = diastolic blood pressure; HBP = high blood pressure; kg/m2 = weight in kilograms divided by the square of height in meters; mm Hg = millimeters of mercury; SBP = systolic blood pressure.
a
The middle trajectory group was set as the reference.
b
According to the World Health Organization 2007 growth reference.15
*
P < .05 compared with the reference group; **P < .01 compared with the reference group.