Table 2.

Baseline renal function before hospitalization among case and control subjects.

		Cases who developed ARF (N=1764)		Controls who did not develop ARF (N=600 820)
Last observed outpatient serum creatinine (mean±s.d.), mg per 100 ml		2.42±1.70		1.05±0.50
Last observed outpatient estimated GFR (mean±s.d.), ml per min per 1.73 m2		43.5±30.7		74.2±21.3
Last observed outpatient estimated GFR, ml per min per 1.73 m2		Median (interquartile range) duration between admission and last known outpatient estimated GFR before hospitalization (in days)		Median (interquartile range) duration between admission and last known outpatient estimated GFR before hospitalization (in days)
≥60	N=469	79 (15, 294)	N=464 720	98 (7, 346)
45–59	N=234	35 (4, 149)	N=97 356	67 (6, 250)
30–44	N=294	25 (4, 110)	N=28 434	25 (2, 135)
15–29	N=476	17 (3, 51)	N=7763	6 (1, 49)
<15 not requiring dialysis	N=291	13 (3, 40)	N=2547	2 (1, 9)

ARF, acute renal failure; GFR, glomerular filtration rate.