Table 2. Characteristics of patient cohorts with and without post-operative AKI.
No AKI (n = 3,985) | Any AKI (n = 587) | P | |||
---|---|---|---|---|---|
mean ± SD/count | column, % | mean ± SD/count | column, % | ||
Age, years | 66.6 ± 11.0 | 68.7 ± 10.9 | <0.001 | ||
Sex | 0.846 | ||||
Male | 2,819 | 70.7 | 413 | 70.4 | |
Pre-operative creatinine, pmol/l | 94.5 ± 31.5 | 117.7 ± 68.7 | <0.001 | ||
eGFR group (MDRD) | <0.001 | ||||
GFR <60 | 1,206 | 31 | 316 | 55.1 | |
GFR 60+ | 2,687 | 69 | 257 | 44.9 | |
NYHA | <0.001 | ||||
I | 998 | 25 | 105 | 17.9 | |
II | 1,005 | 25.2 | 128 | 21.8 | |
III | 1,639 | 41.1 | 240 | 40.9 | |
IV | 343 | 8.6 | 114 | 19.4 | |
Previous MI | <0.001 | ||||
None | 2,689 | 67.5 | 364 | 62 | |
1 | 1,031 | 25.9 | 157 | 26.7 | |
2 or more | 257 | 6.4 | 66 | 11.2 | |
Unknown | 8 | 0.2 | 0 | 0 | |
Last MI | 0.031 | ||||
MI <6 h | 0 | 0.0 | 1 | 0.2 | |
MI >90 days | 644 | 16.2 | 105 | 17.9 | |
MI 1 - 30 days | 441 | 11.1 | 81 | 13.8 | |
MI 31 - 90 days | 186 | 4.7 | 31 | 5.3 | |
MI 6 - 24 h | 17 | 0.4 | 3 | 0.5 | |
No previous MI | 2,696 | 67.7 | 366 | 62.4 | |
LV ejection fraction | <0.001 | ||||
Good (>50%) | 1,772 | 44.5 | 228 | 38.8 | |
Fair (30 - 49%) | 646 | 16.2 | 107 | 18.2 | |
Poor (<30%) | 179 | 4.5 | 50 | 8.5 | |
Not measured | 1,378 | 34.6 | 202 | 34.4 | |
Hypertension | <0.001 | ||||
No hypertension | 1,023 | 25.7 | 90 | 15.3 | |
Treated or BP >140/90 on 1 occasion | |||||
before admission | 2,767 | 69.4 | 456 | 77.7 | |
Claudication | 0.128 | ||||
No | 3,472 | 87.4 | 498 | 85.1 | |
Yes | 501 | 12.6 | 87 | 14.9 | |
Carotid occlusion | 0.629 | ||||
No | 3,873 | 98.2 | 575 | 98.5 | |
Yes | 72 | 1.8 | 9 | 1.5 | |
Diabetes mellitus | <0.001 | ||||
Not diabetic | 3,251 | 81.6 | 422 | 71.9 | |
Diabetic | 734 | 18.4 | 165 | 28.1 | |
Weight, kg | 81.2 ± 21.5 | 83.5 ± 17.2 | 0.013 | ||
Smoking | 0.984 | ||||
Current smoker | 567 | 14.2 | 84 | 14.3 | |
Ex-smoker | 2,025 | 50.8 | 300 | 51.1 | |
Never smoked | 1,393 | 35.0 | 203 | 34.6 | |
Cardiogenic shock | 0.02 | ||||
No | 3,944 | 99.0 | 572 | 97.4 | |
Yes | 41 | 1 | 15 | 2.6 | |
Pre-operative IABP | <0.001 | ||||
No | 3,813 | 95.7 | 533 | 90.8 | |
Yes | 172 | 4.3 | 54 | 9.2 | |
Cardiac procedure | <0.001 | ||||
CABG | 2,300 | 57.7 | 276 | 47.0 | |
CABG + other | 25 | 0.6 | 6 | 1.0 | |
CABG + valve | 482 | 12.1 | 91 | 15.5 | |
CABG + valve + other | 26 | 0.7 | 9 | 1.5 | |
Other | 89 | 2.2 | 34 | 5.8 | |
Valve | 933 | 23.4 | 157 | 26.7 | |
Valve + other | 130 | 3.3 | 14 | 2.4 | |
Additive EuroSCORE | 4.8 ± 3.1 | 6.5 ± 3.6 | <0.001 |
Summary of key pre-operative characteristics of subjects stratified by the presence of post-operative AKI. p values quoted were calculated using Pearson χ 2 tests and unpaired t tests with Bonferroni correction. CABG = Coronary artery bypass grafting; IABP = intraaortic balloon pump; MI = myocardial infarction.