Acute kidney injury in the elderly hospitalized patients

Figures & data

Box 1. Kidney Disease Improwing Global Outcomes (KDIGO) criteria for the diagnosis of acute kidney injury.

• Stage 1 AKI: 1.5–1.9 times baseline, or ≥0.3 mg/dL (≥26.5 µmol/L) increase in the serum creatinine or urine output <0.5 mL/kp per hour for 6–12 hours

• Stage 2 AKI: 2–2.9 times baseline increase in the serum creatinine or urine output <0.5 mL/kg per hour for ≥12 hours

• Stage 3 AKI: 3 times baseline increase in the serum creatinine, or increase in serum creatinine ≥4 mg/dL (≥353.6 µmol/L) or urine output of <0.3 mL/kg per hour for ≥24 hours, or anuria for ≥12 hours, or initiation renal replacement therapy

Table 1. Characteristics of patients.

		Groups
	Total (n = 193)	Renal	Prerenal	Postrenal
	mean ± SD	mean ± SD	mean ± SD	mean ± SD	p
Age (year)	79.99 ± 6.93	77.90 ± 6.63	80.19 ± 6.94	80.44 ± 7.07	^a0.359
BMI	27.29 ± 5.31	32.81 ± 7.56	26.53 ± 4.69	26.25 ± 3.03	^a0.001*
SBP	115.45 ± 27.59	141.11 ± 34.62	110.76 ± 25.69	122.67 ± 21.11	^b0.000*
DBP	69.17 ± 14.62	76.67 ± 12.83	66.96 ± 14.21	75.56 ± 14.76	^b0.001*
Mean hospital stay (day); (Median)	10.11 ± 8.62	10.60 ± 6.93	10.16 ± 9.23	9.44 ± 6.17	^b0.616
Recovery (day)	9.90 ± 39.19	8.31 ± 8.24	10.59 ± 44.5	7.06 ± 6.77	^b0.153
	n (%)	n (%)	n (%)	n (%)	p
Gender
female	101	12 (60.0)	84 (57.5)	5 (18.5)	^c0.001*
male	92	8 (40.0)	62 (42.5)	22 (81.5)
Mortality
no	157	18 (90.0)	115 (78.8)	24 (88.9)	^d0.356
yes	36	2 (10.0)	31 (21.2)	3 (11.1)

Notes: ^aOneway ANOVA test.

^bKruskal–Wallis test.

^cPearson chi square test

^dFisher–Freeman–Halton test.

*p < 0.05.

**p < 0.01.

Table 2. Laboratory parameters.

		Groups
	Total (n = 193)	Renal	Prerenal	Postrenal
	mean ± SD	mean ± SD	mean ± SD	mean ± SD	p
Glucose	107.44 ± 43.15	105.10 ± 32.53	110.73 ± 46.07	92.11 ± 29.90	^b0.051
	−100	−100	−103.5	−83
Na	137.75 ± 10.90	132.75 ± 6.36	138.91 ± 11.68	135.22 ± 7.32	^b0.043*
P	4.78 ± 2.01	5.11 ± 2.14	4.60 ± 1.93	5.47 ± 2.18	^b0.122
	−4.5	−4.4	−4.4	−5
HB	10.96 ± 2.45	11.62 ± 1.85	10.89 ± 2.53	10.86 ± 2.37	^a0.467
CRP	11.19 ± 10.73	7.61 ± 7.29	11.83 ± 11.46	10.74 ± 8.47	^b0.251
	−8.85	−6.9	−9.37	−8.3
BUN	83.34 ± 47.22	71.20 ± 48.44	83.59 ± 47.21	90.96 ± 46.36	^b0.134
	−77	−66	−77	−85
Potassium	4.63 ± 1.20	4.56 ± 1.14	4.49 ± 1.19	5.44 ± 1.02	^b0.000**
PTH	153.53 ± 103.24	170.64 ± 121.03	141.26 ± 98.86	176.32 ± 101.49	^b0.445
	−131.25	−165	−128.1	−139
HCT	33.44 ± 7.59	35.02 ± 5.15	33.33 ± 7.99	32.90 ± 6.88	^a0.598
Creatinine	4.36 ± 3.13	5.16 ± 3.43	3.72 ± 2.62	7.21 ± 3.73	^b0.000**
	−3.2	−3.23	−2.89	−6.5
Calcium	8.31 ± 0.81	8.48 ± 0.48	8.27 ± 0.88	8.37 ± 0.54	^a0.525
Albumin	2.65 ± 0.63	2.72 ± 0.69	2.63 ± 0.65	2.72 ± 0.46	^b0.579
Ferritin	363.19 ± 488.56	303.58 ± 344.44	388.69 ± 534.44	280.87 ± 303.13	^b0.659
	−217.5	−200.11	−219	−207.5

Notes: ^aOneway ANOVA test.

^bKruskal–Wallis test.

*p < 0.05.

**p < 0.01.

Table 3. Medications.

	Renal	Prerenal	Postrenal
	n (%)	n (%)	n (%)	p
NSAID	8 (40.0)	44 (30.1)	4 (14.8)
PPI	5 (25.0)	29 (19.9)	5 (18.5)
Thiazide	6 (30.0)	33 (22.6)	3 (11.1)
Spironolactone	0 (0.0)	19 (13.0)	4 (14.8)
Furosemide	4 (20.0)	30 (20.5)	4 (14.8)
Anti hypertensive	12 (60.0)	71 (51.4)	9 (66.7)	^a0.174
CA channel Blockers	4 (20.0)	25 (17.1)	0 (0.0)
ACEI	4 (20.0)	30 (20.5)	3 (11.1)
ARB	8 (40.0)	26 (17.8)	6 (22.2)
Antibiotics	9 (45.0)	8 (5.5)	1 (3.7)	^b0.000*

Notes: ^aPearson chi square test.

^bFisher–Freeman–Halton test.

*p < 0.05.

Table 4. RRT requirement – recovery.

		Groups
	Total (n = 193)	Renal	Prerenal	Postrenal
	n	n (%)	n (%)	n (%)	p
HD	43	6 (30.0)	26 (17.8)	11 (40.7)	^b0.022*
Recovery	126	13 (65.0)	97 (66.4)	16 (59.3)	^a0.771

Notes: ^aPearson chi square test.

^bFisher–Freeman–Halton test.

*p < 0.05.

Table 5. Risk factors for permanent kidney failure.

	Renal recovery
	Yes	No	^ap
BMI	27.21 ± 5.48	27.48 ± 5.01	0.828
SBP	116.28 ± 26.26	113.84 ± 30.16	0.571
DBP	69.16 ± 14.90	69.19 ± 14.18	0.990
	n (%)	n (%)	p
Gender
Female	67 (53.2)	34 (50.7)	^b0.748
Male	59 (46.8)	33 (49.3)
HT
No	98 (80.3)	50 (79.4)	^b1.000
Yes	24 (19.7)	13 (20.6)
Mortality
Yes	6 (4.8)	30 (44.8)	^b0.001**
No	120 (95.2)	37 (55.2)

Notes:

^aStudent t-test.

^bYates continuity correction.

**p < 0.01.

Table 6. Risk factors for permanent renal failure.

		Recovery
		No	Yes
		n (%)	n (%)	p
Hemodialysis	No	40 (59.7)	110 (87.3)	^a0.001**
	Yes	27 (40.3)	16 (12.7)
Diuretic use	No	41 (61.2)	79 (62.7)	^b0.837
	Yes	26 (38.8)	47 (37.3)
Antihypertensive drugs	No	38 (56.7)	63 (50.0)	^b0.374
	Yes	29 (43.3)	63 (50.0)
Antibiotics use	No	60 (89.6)	115 (91.3)	^a0.896
	Yes	7 (10.4)	11 (8.7)
Dementia	No	57 (85.1)	107 (84.9)	^a1.000
	Yes	10 (14.9)	19 (15.1)
Diabetes mellitus	No	42 (62.7)	89 (70.6)	^a0.260
	Yes	25 (37.3)	37 (29.4)
CHF	No	46 (68.7)	96 (76.2)	^a0.338
	Yes	21 (31.3)	30 (23.8)
CAD	No	59 (88.1)	110 (87.3)	^a1.000
	Yes	8 (11.9)	16 (12.7)

Notes: ^aYates continuity correction.

^bPearson chi-square.

Table 7. Risk factors for mortality.

	Mortality (n = 36)	No mortality (n = 157)
	Mean ± SD	Mean ± SD	^ap
Age (year)	83.47 ± 7.51	79.19 ± 6.56	^c0.001**
BMI	25.65 ± 4.29	27.55 ± 5.44	0.254
SBP (mmHg)	107.24 ± 25.37	117.30 ± 27.81	0.054
DBP (mmHg)	64.15 ± 13.70	70.31 ± 14.63	0.026*
Hemodialysis treatment	15 (41.7%)	28 (17.8%)	0.004**
No HD	21 (58%)	129 (82%
	n (%)	n (%)	p
Gender
Female	17 (47.2%)	84 (53.5%)	^b0.496
Male	19 (52.8%)	73 (46.5%)

Notes: ^aStudent t-test.

^bPearson chi-square.

^cYates continuity correction.

**p < 0.01.

Table 8. Analysis risk factors for mortality.

			%95 CI
	p	ODDS	Lower	Upper
Hemodialysis	0.111	2.238	0.83	6.03
Lower blood pressure	0.049*	2.602	1.00	6.74
CRP >5	0.043*	3.706	1.04	13.21
HB (<12)	0.038*	3.077	1.07	8.87

*p < 0.05.