Table 2.
Associations among various early HbA1c exposure periods and subsequent outcomes
| Microvascular events |
Macrovascular events |
Death |
|||||||
|---|---|---|---|---|---|---|---|---|---|
| Early period and mean glycemic control | n/total n | Adjusted HR (95% CI) | P value | n/total n | Adjusted HR (95% CI) | P value | n/total n | Adjusted HR (95% CI) | P value |
| 0–1 year | |||||||||
| HbA1c | |||||||||
| <6.5% (<48 mmol/mol) | 864/14,080 | Reference | 3,668/13,455 | Reference | 744/14,286 | Reference | |||
| 6.5% to <7.0% (48 to <53 mmol/mol) | 372/5,774 | 1.204 (1.063–1.365) | 0.004 | 1,497/5,552 | 1.188 (1.116–1.264) | <0.0001 | 268/5,877 | 1.137 (0.985–1.313) | 0.079 |
| 7.0% to <8.0% (53 to <64 mmol/mol) | 385/4,656 | 1.391 (1.226–1.578) | <0.0001 | 1,244/4,501 | 1.287 (1.203–1.377) | <0.0001 | 224/4,730 | 1.290 (1.104–1.507) | 0.001 |
| 8.0% to <9.0% (64 to <75 mmol/mol) | 154/1,390 | 1.603 (1.340–1.917) | <0.0001 | 383/1,351 | 1.369 (1.227–1.527) | <0.0001 | 68/1,418 | 1.262 (0.978–1.628) | 0.073 |
| ≥9.0% (≥75 mmol/mol) | 232/1,259 | 2.213 (1.892–2.590) | <0.0001 | 382/1,220 | 1.485 (1.329–1.659) | <0.0001 | 66/1,290 | 1.320 (1.017–1.713) | 0.037 |
| Missing | 647/7,047 | 1.354 (1.218–1.505) | <0.0001 | 1,899/6,867 | 1.112 (1.050–1.177) | 0.0003 | 437/7,136 | 1.235 (1.094–1.394) | 0.001 |
| 0–2 years | |||||||||
| HbA1c | |||||||||
| <6.5% (<48 mmol/mol) | 809/14,673 | Reference | 3,612/13,860 | Reference | 817/14,940 | Reference | |||
| 6.5% to <7.0% (48 to <53 mmol/mol) | 451/7,517 | 1.259 (1.117–1.419) | 0.0002 | 1,866/7,143 | 1.158 (1.093–1.228) | <0.0001 | 368/7,675 | 1.093 (0.962–1.241) | 0.172 |
| 7.0% to <8.0% (53 to <64 mmol/mol) | 544/7,144 | 1.497 (1.331–1.684) | <0.0001 | 1,788/6,842 | 1.264 (1.189–1.344) | <0.0001 | 368/7,295 | 1.240 (1.088–1.414) | 0.001 |
| 8.0% to <9.0% (64 to <75 mmol/mol) | 258/2,529 | 1.700 (1.460–1.980) | <0.0001 | 620/2,426 | 1.279 (1.168–1.401) | <0.0001 | 128/2,592 | 1.274 (1.047–1.551) | 0.016 |
| ≥9.0% (≥75 mmol/mol) | 408/2,159 | 2.756 (2.396–3.170) | <0.0001 | 624/2,112 | 1.539 (1.400–1.692) | <0.0001 | 126/2,235 | 1.528 (1.245–1.876) | <0.0001 |
| 0–3 years | |||||||||
| HbA1c | |||||||||
| <6.5% (<48 mmol/mol) | 619/12,475 | Reference | 2,931/11,635 | Reference | 717/12,769 | Reference | |||
| 6.5% to <7.0% (48 to <53 mmol/mol) | 412/7,883 | 1.194 (1.049–1.359) | 0.007 | 1,818/7,347 | 1.126 (1.059–1.197) | 0.0001 | 375/8,057 | 0.975 (0.856–1.109) | 0.696 |
| 7.0% to <8.0% (53 to <64 mmol/mol) | 551/8,310 | 1.453 (1.281–1.648) | <0.0001 | 1,931/7,873 | 1.208 (1.134–1.286) | <0.0001 | 433/8,541 | 1.189 (1.044–1.353) | 0.009 |
| 8.0% to <9.0% (64 to <75 mmol/mol) | 293/3,081 | 1.835 (1.571–2.145) | <0.0001 | 732/2,952 | 1.329 (1.216–1.453) | <0.0001 | 162/3,188 | 1.376 (1.145–1.654) | 0.001 |
| ≥9.0% (≥75 mmol/mol) | 406/2,084 | 3.193 (2.738–3.723) | <0.0001 | 563/2,041 | 1.471 (1.327–1.631) | <0.0001 | 120/2,182 | 1.503 (1.211–1.865) | 0.0002 |
| 0–4 years | |||||||||
| HbA1c | |||||||||
| <6.5% (<48 mmol/mol) | 493/10,627 | Reference | 2,322/9,692 | Reference | 621/10,898 | Reference | |||
| 6.5% to <7.0% (48 to <53 mmol/mol) | 401/8,097 | 1.252 (1.091–1.436) | 0.001 | 1,719/7,410 | 1.100 (1.031–1.174) | 0.004 | 399/8,302 | 1.013 (0.889–1.155) | 0.842 |
| 7.0% to <8.0% (53 to <64 mmol/mol) | 542/9,306 | 1.461 (1.277–1.673) | <0.0001 | 2,019/8,710 | 1.224 (1.145–1.308) | <0.0001 | 482/9,608 | 1.224 (1.074–1.395) | 0.002 |
| 8.0% to <9.0% (64 to <75 mmol/mol) | 312/3,567 | 1.894 (1.608–2.231) | <0.0001 | 770/3,352 | 1.299 (1.185–1.425) | <0.0001 | 187/3,697 | 1.453 (1.211–1.742) | <0.0001 |
| ≥9.0% (≥75 mmol/mol) | 412/2,115 | 3.687 (3.123–4.352) | <0.0001 | 534/2,073 | 1.535 (1.374–1.714) | <0.0001 | 118/2,232 | 1.676 (1.337–2.100) | <0.0001 |
| 0–5 years | |||||||||
| HbA1c | |||||||||
| <6.5% (<48 mmol/mol) | 399/9,209 | Reference | 1,862/8,226 | Reference | 552/9,475 | Reference | |||
| 6.5% to <7.0% (48 to <53 mmol/mol) | 377/8,244 | 1.263 (1.091–1.462) | 0.002 | 1,596/7,389 | 1.102 (1.027–1.182) | 0.007 | 423/8,465 | 1.070 (0.937–1.221) | 0.318 |
| 7.0% to <8.0% (53 to <64 mmol/mol) | 519/10,118 | 1.441 (1.246–1.666) | <0.0001 | 2,038/9,315 | 1.259 (1.173–1.352) | <0.0001 | 518/10,500 | 1.238 (1.083–1.415) | 0.002 |
| 8.0% to <9.0% (64 to <75 mmol/mol) | 331/3,841 | 2.111 (1.779–2.506) | <0.0001 | 727/3,556 | 1.269 (1.150–1.400) | <0.0001 | 200/3,984 | 1.554 (1.294–1.867) | <0.0001 |
| ≥9.0% (≥75 mmol/mol) | 418/2,184 | 4.094 (3.427–4.893) | <0.0001 | 524/2,134 | 1.596 (1.420–1.794) | <0.0001 | 114/2,313 | 1.747 (1.382–2.208) | <0.0001 |
| 0–6 years | |||||||||
| HbA1c | |||||||||
| <6.5% (<48 mmol/mol) | 343/8,192 | Reference | 1,524/7,122 | Reference | 505/8,463 | Reference | |||
| 6.5% to <7.0% (48 to <53 mmol/mol) | 319/8,328 | 1.137 (0.970–1.333) | 0.112 | 1,433/7,362 | 1.074 (0.996–1.159) | 0.064 | 432/8,580 | 1.097 (0.959–1.255) | 0.177 |
| 7.0% to <8.0% (53 to <64 mmol/mol) | 523/10,696 | 1.543 (1.324–1.797) | <0.0001 | 1,967/9,671 | 1.299 (1.204–1.402) | <0.0001 | 547/11,120 | 1.278 (1.116–1.464) | 0.0004 |
| 8.0% to <9.0% (64 to <75 mmol/mol) | 322/4,034 | 2.252 (1.879–2.700) | <0.0001 | 713/3,683 | 1.368 (1.233–1.517) | <0.0001 | 207/4,199 | 1.561 (1.296–1.880) | <0.0001 |
| ≥9.0% (≥75 mmol/mol) | 424/2,233 | 4.869 (4.030–5.882) | <0.0001 | 486/2,158 | 1.734 (1.530–1.964) | <0.0001 | 116/2,375 | 1.932 (1.523–2.451) | <0.0001 |
| 0–7 years | |||||||||
| HbA1c | |||||||||
| <6.5% (<48 mmol/mol) | 272/7,372 | Reference | 1,222/6,245 | Reference | 476/7,660 | Reference | |||
| 6.5% to <7.0% (48 to <53 mmol/mol) | 295/8,371 | 1.194 (1.006–1.418) | 0.043 | 1,320/7,226 | 1.135 (1.046–1.232) | 0.002 | 441/8,654 | 1.076 (0.938–1.233) | 0.295 |
| 7.0% to <8.0% (53 to <64 mmol/mol) | 481/11,178 | 1.606 (1.359–1.899) | <0.0001 | 1,783/9,959 | 1.327 (1.221–1.442) | <0.0001 | 562/11,672 | 1.269 (1.106–1.457) | 0.001 |
| 8.0% to <9.0% (64 to <75 mmol/mol) | 310/4,202 | 2.580 (2.123–3.135) | <0.0001 | 689/3,797 | 1.577 (1.412–1.760) | <0.0001 | 213/4,389 | 1.661 (1.378–2.003) | <0.0001 |
| ≥9.0% (≥75 mmol/mol) | 414/2,201 | 6.437 (5.246–7.899) | <0.0001 | 447/2,107 | 2.113 (1.847–2.417) | <0.0001 | 115/2,362 | 2.181 (1.713–2.778) | <0.0001 |
All models adjusted for year of diagnosis, age at diagnosis, sex, race/ethnicity, BMI, systolic and diastolic blood pressure, total cholesterol, HDL cholesterol, smoking status, HbA1c after each early period, and comorbidity.