A population-based case-crossover study of polyethylene glycol use and acute renal failure risk in the elderly

Table 1 Characteristics of elderly patients who had at least one claim for any healthcare service in Seoul between January 1, 2005 and December 31, 2005 and those who were hospitalized for acute renal failure among the population n (%)

	Total of elderly patients	Patients hospitalized for ARF
Age (yr)
mean ± SD	72.0 ± 6.1	75.9 ± 7.3
65-69	472 614 (43.2)	270 (23.4)
70-74	297 348 (27.2)	260 (22.5)
75-79	179 562 (16.4)	272 (23.5)
80-84	96 131 (8.8)	197 (17)
≥ 85	47 607 (4.4)	157 (13.6)
Sex
Male	438 795 (40.1)	587 (50.8)
Female	654 497 (59.9)	569 (49.2)
Total	1 093 262 (100)	1156 (100)

ARF: Acute renal failure.

Table 2 Characteristics of elderly patients with polyethylene glycol prescription prior to hospitalization for acute renal failure

	n (%)
Age (yr)
mean ± SD	70.6 ± 4.6
65-69	8 (47.1)
70-74	5 (29.4)
75-79	3 (17.6)
80-84	1 (5.9)
Sex
Male	14 (82.4)
Female	3 (17.6)
Diagnoses on the day of PEG prescription
Colorectal cancer	6 (35.3)
Gastric or duodenal ulcer, gastritis or duodenitis, intestinal disorders	6 (35.3)
Renal disease	3 (17.6)
Fibrosis and cirrhosis of liver	2 (11.8)
Liver cancer	1 (5.9)
Pancreatic cancer	1 (5.9)
Total	17 (100)

PEG: Polyethylene glycol.

Table 3 Association between polyethylene glycol and the risk of acute renal failure with respect to time-window periods by matched ratio of case and control period

Time-window period	Case period (n = 17)	Control period (n = 34)	Crude OR (95% CI)1	Adjusted OR (95% CI)2
2 wk
PEG non-users	16	31	1	1
PEG users	1	3	0.7 (0.07-6.41)	0.4 (0.03-5.24)
4 wk
PEG non-users	15	31	1	1
PEG users	2	3	1.3 (0.22-7.99)	2.1 (0.16-27.78)

¹Calculated by conditional logistic regression;

²Calculated by conditional logistic regression adjusted for use of nephrotoxic drugs (diuretics, angiotensin converting enzyme inhibitors, angiotensin receptor blockers, non-steroidal anti-inflammatory drugs, aminoglycoside, β-lactams, anti-viral agents, antimycotics, anti-cancer drugs, and contrast media). PEG: Polyethylene glycol; OR: Odds ratio.