Table 3. Multivariable Association of HbA1c Levels and Risk of Type 2 Diabetesa.
| Characteristic | HR (95% CI) | ||
|---|---|---|---|
| Entire cohort (N = 74 552) | Subset with glycemic follow-up measure (n = 41 541) | Subset censored at last glycemic measure (n = 41 541) | |
| Unadjusted | |||
| HbA1c, % | |||
| <5.5 | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| 5.5-5.6 | 1.7 (1.3-2.3) | 1.7 (1.3-2.2) | 1.8 (1.4-2.3) |
| 5.7-5.8 | 3.2 (2.4-4.1) | 2.9 (2.2-3.7) | 3.2 (2.4-4.1) |
| 5.9-6.0 | 11.2 (8.7-14.4) | 9.8 (7.6-12.6) | 10.6 (8.2-13.7) |
| 6.1-6.2 | 30.9 (23.2-41.0) | 25.3 (19.0-33.6) | 26.7 (20.1-35.5) |
| 6.3-6.4 | 103.4 (74.1-144.1) | 81.4 (58.3-113.5) | 90.5 (64.8-126.4) |
| Adjusted | |||
| HbA1c, % | |||
| <5.5 | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| 5.5-5.6 | 1.7 (1.3-2.2) | 1.6 (1.2-2.1) | 1.7 (1.3-2.3) |
| 5.7-5.8 | 2.8 (2.1-3.6) | 2.6 (2.0-3.4) | 2.9 (2.2-3.8) |
| 5.9-6.0 | 9.3 (7.2-12.1) | 8.4 (6.5-10.8) | 8.9 (6.9-11.5) |
| 6.1-6.2 | 23.3 (17.4-31.3) | 20.8 (15.5-27.9) | 22.3 (16.6-29.9) |
| 6.3-6.4 | 71.9 (51.1-101.1) | 62.3 (44.3-87.7) | 68.9 (48.9-97.0) |
| Sex | |||
| Female | 1.5 (1.3-1.8) | 1.4 (1.2-1.6) | 1.2 (1.0-1.4) |
| Male | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| Age, y | |||
| 10-11 | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| 12-14 | 1.0 (0.8-1.2) | 1.0 (0.8-1.2) | 1.0 (0.8-1.3) |
| 15-17 | 1.7 (1.4-2.1) | 1.9 (1.5-2.3) | 1.9 (1.5-2.3) |
| BMI categoryb | |||
| Overweight | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| Moderate obesity | 2.0 (1.4-2.7) | 1.9 (1.4-2.7) | 1.9 (1.4-2.6) |
| Severe obesity | 5.2 (3.9-7.1) | 5.0 (3.7-6.7) | 4.6 (3.4-6.2) |
| Race and ethnicity | |||
| Asian or Pacific Islander | 1.7 (1.3-2.2) | 1.7 (1.3-2.3) | 1.7 (1.3-2.3) |
| Black | 0.8 (0.6-1.1) | 0.8 (0.6-1.0) | 0.8 (0.6-1.0) |
| Hispanic | 1.1 (0.8-1.4) | 1.0 (0.8-1.4) | 1.0 (0.8-1.3) |
| White | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| Other or unkownc | 1.0 (0.6-1.5) | 1.0 (0.7-1.6) | 1.1 (0.7-1.7) |
| NDI quartiled | |||
| 1 (Least deprived) | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| 2 | 1.0 (0.8-1.2) | 1.0 (0.8-1.2) | 1.0 (0.8-1.3) |
| 3 | 1.2 (1.0-1.5) | 1.2 (1.0-1.6) | 1.3 (1.0-1.6) |
| 4 (Most deprived) | 1.2 (1.0-1.5) | 1.3 (1.0-1.6) | 1.4 (1.1-1.7) |
| Unknown | 1.0 (0.3-4.2) | 1.1 (0.3-4.3) | 1.2 (0.3-4.8) |
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); HbA1c, hemoglobin A1c; HR, hazard ratio; NDI, Neighborhood Deprivation Index.
Sensitivity analyses were conducted, restricting the cohort to those with a follow-up glycemic measure and to those with a follow-up glycemic measure, censored at the last glycemic measure.
Defined as overweight (BMI 85th to <95th percentile), moderate obesity (BMI 100% to <120% of 95th percentile), and severe obesity (BMI ≥120% of 95th percentile).
Includes American Indian or Alaska Native race, multiple races or ethnicities, and unknown race or ethnicity.
Scores ranged from −2.1 to 4.4; higher scores represent greater estimated neighborhood deprivation. Scores were not available for 0.3% of children.