Table 2. Associations Between Clinical Variables and Risk of Confirmed or Suspected Microalbuminuria.
| Variable | Unadjusted hazard ratio (95% CI)a | P value |
|---|---|---|
| Male (vs female) | 0.88 (0.66-1.17) | .38 |
| Age at diagnosis of diabetes | 1.11 (1.07-1.15) | <.001 |
| Mean HbA1c since diagnosis | 1.37 (1.26-1.49) | <.001 |
| DKA episodes of all severities | ||
| Each episode | 1.73 (1.50-2.01) | <.001 |
| No. of episodes | ||
| 0 | 1 [Reference] | <.001 |
| 1 | 1.38 (1.00-1.92) | |
| 2 | 2.97 (1.67-5.27) | |
| 3 | 7.90 (4.65-13.4) | |
| ≥4 | 4.94 (1.79-13.7) | |
| Moderate or severe DKA | ||
| Each episode | 1.91 (1.58-2.32) | <.001 |
| No. of episodes | ||
| 0 | 1 [Reference] | <.001 |
| 1 | 1.55 (1.10-2.20) | |
| 2 | 3.85 (2.03-7.31) | |
| 3 | 8.67 (4.13-18.2) | |
| ≥4 | 15.6 (2.16-112) | |
| AKI episodes of any severity | ||
| Each episode | 1.87 (1.58-2.21) | <.001 |
| No. of episodes | ||
| 0 | 1 [Reference] | <.001 |
| 1 | 1.33 (0.92-1.94)b | |
| 2 | 4.52 (2.65-7.73) | |
| 3 | 8.20 (4.03-16.7) | |
| ≥4 | 9.31 (2.87-30.2) | |
| Stage 2 or 3 AKI | ||
| Each episode | 1.98 (1.62-2.42) | <.001 |
| No. of episodes | ||
| 0 | 1 [Reference] | <.001 |
| 1 | 1.54 (1.02-2.33) | |
| 2 | 4.82 (2.50-9.30) | |
| 3 | 8.67 (3.85-19.5) | |
| ≥4 | 15.0 (2.08-108) |
Abbreviations: AKI, acute kidney injury; DKA, diabetic ketoacidosis; HbA1c, hemoglobin A1c.
a
Hazard ratio represents increased risk for each 1-year increase in age at diagnosis and each 1% increase in mean HbA1c level since diagnosis.
b
Hazard ratio values reported represent estimates when patients have experienced exactly 1, 2, 3 or 4 episodes or more of acute kidney injury, compared with 0 episodes. Sample sizes at some levels were small, affecting power to detect significant differences for individual levels; however, the overall comparison across levels indicated a significant association of number of acute kidney injury episodes with risk of microalbuminuria.