Table 1.
Baseline characteristics of study participants by distinct body mass index trajectories
| Variables | Total (n = 4,519) | Trajectory 1: Low (n = 884) | Trajectory 2: Moderate (n = 1,511) | Trajectory 3: Moderate‐high (n = 1,510) | Trajectory 4: High (n = 614) | P‐value* | P for trend† |
|---|---|---|---|---|---|---|---|
| Age (years) | 42.0 (32.0–57.0) | 32.0 (27.0–43.0) | 41.0 (31.0–55.0) | 47.0 (37.0–61.0) | 47.0 (37.0–63.0) | <0.001 | <0.001 |
| Male (%) | 2,438 (53.9) | 194 (22.0) | 616 (40.8) | 1,115 (73.8) | 513 (83.6) | <0.001 | <0.001 |
| BMI (kg/m2) | 23.4 (20.9–25.6) | 19.4 (18.5–20.1) | 22.0 (21.1–22.9) | 25.1 (24.2–25.9) | 28.2 (27.3–29.2) | <0.001 | <0.001 |
| WC (cm) | 80.0 (71.0–87.0) | 67.0 (64.0–71.0) | 75.0 (71.0–80.0) | 85.0 (80.0–88.0) | 93.0 (88.0–96.0) | <0.001 | <0.001 |
| Race (%) | |||||||
| Han | 4,350 (96.6) | 851 (96.3) | 1,466 (97.5) | 1,443 (95.9) | 590 (96.7) | 0.102 | 0.577 |
| Other minorities | 153 (3.4) | 33 (3.7) | 38 (2.5) | 62 (4.1) | 20 (3.3) | ||
| Occupation (%) | |||||||
| Civil servants | 1,887 (41.8) | 230 (26.0) | 574 (38.0) | 755 (50.0) | 328 (53.4) | <0.001 | ― |
| Educators | 166 (3.7) | 26 (2.9) | 56 (3.7) | 68 (4.5) | 16 (2.6) | ||
| Media workers | 747 (16.5) | 168 (19.0) | 244 (16.2) | 238 (15.8) | 97 (15.8) | ||
| Medical workers | 1,090 (24.1) | 353 (39.9) | 429 (28.4) | 239 (15.8) | 69 (11.2) | ||
| Bank workers | 228 (5.1) | 48 (5.4) | 91 (6.0) | 63 (4.2) | 26 (4.2) | ||
| Police officers | 132 (2.9) | 8 (0.9) | 37 (2.5) | 57 (3.8) | 30 (4.9) | ||
| Others | 269 (6.0) | 51 (5.8) | 80 (5.3) | 90 (6.0) | 48 (7.8) | ||
| Current smoker (%) | 989 (26.5) | 71 (9.5) | 239 (19.4) | 450 (36.5) | 229 (44.6) | <0.001 | <0.001 |
| Current alcohol drinker (%) | 2,034 (60.1) | 259 (38.3) | 608 (54.6) | 807 (71.6) | 360 (77.4) | <0.001 | <0.001 |
| Married status (%) | 3,415 (86.3) | 535 (70.9) | 1,108 (84.7) | 1,265 (93.9) | 507 (92.9) | <0.001 | <0.001 |
| Family history of diabetes (%) | 347 (7.7) | 65 (7.4) | 119 (7.9) | 117 (7.8) | 46 (7.5) | 0.968 | 0.923 |
| Hypertension (%) | 946 (21.6) | 49 (5.8) | 201 (13.8) | 426 (28.9) | 270 (45.5) | <0.001 | <0.001 |
| Use of antihypertensive (%) | 407 (9.0) | 24 (2.7) | 91 (6.0) | 179 (11.9) | 113 (18.4) | <0.001 | <0.001 |
| Fasting blood glucose (mmol/L) | 5.0 (4.7–5.3) | 4.8 (4.5–5.1) | 4.9 (4.7–5.2) | 5.1 (4.8–5.5) | 5.2 (4.8–5.6) | <0.001 | <0.001 |
| Total cholesterol (mmol/L) | 4.7 (4.2–5.3) | 4.4 (3.9–5.0) | 4.6 (4.1–5.3) | 4.8 (4.3–5.5) | 4.9 (4.3–5.5) | <0.001 | <0.001 |
| Triglycerides (mmol/L) | 1.13 (0.79–1.67) | 0.79 (0.62–1.06) | 1.00 (0.73–1.44) | 1.37 (0.99–1.96) | 1.62 (1.20–2.43) | <0.001 | <0.001 |
| Hemoglobin (g/L) | 133.0 (124.0–144.0) | 125.0 (119.0–132.0) | 129.0 (122.0–140.0) | 140.5 (130.0–148.0) | 143.0 (133.8–150.0) | <0.001 | <0.001 |
| Creatinine (μmol/L) | 66.0 (54.0–78.0) | 55.0 (50.0–64.0) | 61.0 (52.0–73.0) | 73.0 (60.0–81.0) | 75.0 (65.0–84.0) | <0.001 | <0.001 |
| Uric acid (μmol/L) | 282.0 (221.0–349.0) | 216.0 (183.0–268.0) | 255.0 (209.0–318.0) | 319.0 (261.8–379.0) | 350.0 (295.0–410.0) | <0.001 | <0.001 |
Data were presented as median (interquartile range) or n (%). Distinct body mass index (BMI) trajectories were identified using six BMI tests (during 2011–2016). *P‐values are calculated using Kruskal–Wallis test for continuous variables, and the χ2‐test for categorical variables. † P‐values for trend are calculated using Spearman's correlation for continuous variables, and the Cochran–Armitage trend test for binary variables. WC, waist circumference.