Risk of high A1C level (≥6.5%) by weight status categories
| BMI category | A1C <6.5% n (row %) | A1C ≥6.5% n (row %) | RR (95% CI) | P value | RD (95% CI) | P value |
| All participants (n=5702)* | ||||||
| Underweight | 105 (78.4%) | 29 (21.64%) | 3.6 (2.5 to 5.1) | <0.0001 | 15.7% (8.6% to 22.7%) | <0.0001 |
| Healthy weight | 1164 (67.8%) | 554 (32.3%) | 5.5 (4.6 to 6.3) | <0.0001 | 26.3% (23.9% to 28.6%) | <0.0001 |
| Overweight | 498 (75.5%) | 162 (24.6%) | 4.1 (3.4 to 5.0) | <0.0001 | 18.6% (15.2% to 21.9%) | |
| Obese | 2999 (94.0%) | 191 (6.0%) | Ref | Ref | ||
| Children | ||||||
| Ages 4–9 (n=1205) | ||||||
| Underweight | 26 (76.5%) | 8 (23.5%) | 6.6 (3.2 to 13.7) | <0.0001 | 20.0% (5.6% to 34.3%) | 0.0064 |
| Healthy weight | 302 (70.6%) | 126 (29.4%) | 8.2 (5.3 to 12.7) | <0.0001 | 25.9% (21.3% to 30.4%) | <0.0001 |
| Overweight | 92 (72.4%) | 35 (27.6%) | 7.7 (4.7 to 12.7) | <0.0001 | 24.0% (16.1% to 31.9%) | <0.0001 |
| Obese | 594 (96.4%) | 22 (3.6%) | Ref | Ref | ||
| Pre-teens | ||||||
| Ages 10–12 (n=1194) | ||||||
| Underweight | 17 (73.9%) | 6 (26.1%) | 8.7 (3.9 to 19.4) | <0.0001 | 23.1% (5.1% to 41.1%) | 0.0118 |
| Healthy weight | 165 (61.1%) | 105 (38.9%) | 13.0 (8.5 to 20.0) | <0.0001 | 35.9% (30.0% to 41.8%) | <0.0001 |
| Overweight | 102 (77.9%) | 29 (22.1%) | 7.4 (4.4 to 12.4) | <0.0001 | 19.2% (11.9% to 26.4%) | <0.0001 |
| Obese | 747 (97.0%) | 23 (3.0%) | Ref | Ref | ||
| Teenagers | ||||||
| Ages 13–19 (n=3303) | ||||||
| Underweight | 62 (80.5%) | 15 (19.5%) | 2.4 (1.5 to 3.9) | 0.0003 | 11.4% (2.5% to 20.3%) | 0.0125 |
| Healthy weight | 697 (68.3%) | 323 (31.7%) | 3.9 (3.3 to 4.7) | <0.0001 | 23.6% (20.5% to 26.7%) | <0.0001 |
| Overweight | 304 (75.6%) | 98 (24.4%) | 3.0 (2.4 to 3.8) | <0.0001 | 16.3% (11.9% to 20.7%) | <0.0001 |
| Obese | 1658 (91.9%) | 146 (8.1%) | Ref | Ref | ||
Weight status definitions via BMI percentiles with underweight = <5th, healthy weight = 5th to <85th, overweight = 85th to <95th and obese ≥95th.
*Crude results for all participants are reported here, even though there is a statistically significant interaction between age and weight status category (P value<0.0001).
BMI, body mass index; RD, risk difference; Ref, reference category; RR, relative risk.