Table 3 The association between admission serum ionized calcium levels and in-hospital acute kidney injury occurrence.

(a) Acute kidney injury

 ≤ 4.39

1.69 (1.44–1.99)

 < 0.001

1.45 (1.21–1.74)

 < 0.001

4.40–4.59

1.49 (1.29–1.72)

 < 0.001

1.33 (1.14–1.56)

 < 0.001

4.60–4.79

1.23 (1.08–1.40)

0.002

1.13 (0.98–1.30)

0.09

4.80–4.99

1.13 (0.99–1.29)

0.07

1.07 (0.93–1.23)

0.37

5.00–5.19

1 (reference)

–

1 (reference)

–

 ≥ 5.20

1.51 (1.26–1.82)

 < 0.001

1.26 (1.04–1.54)

0.02

(b) Acute kidney injury stage 2–3

 ≤ 4.39

4.43 (3.07–6.41)

 < 0.001

2.41 (1.63–3.56)

 < 0.001

4.40–4.59

2.50 (1.73–3.60)

 < 0.001

1.75 (1.20–2.56)

0.004

4.60–4.79

1.90 (1.35–2.68)

 < 0.001

1.55 (1.09–2.21)

0.01

4.80–4.99

1.56 (1.09–2.22)

0.01

1.36 (0.95–1.95)

0.10

5.00–5.19

1 (reference)

–

1 (reference)

–

 ≥ 5.20

2.45 (1.58–3.78)

 < 0.001

1.83 (1.17–2.87)

0.008