Table 2

Odds ratios (95% confidence intervals) for bladder cancer among regular users of phenacetin and paracetamol, with adjustment for other drugs, and among exclusive users.

Drug use
Adjusted Modela
Exclusive Use Modelb

Controls N(%)
Cases N(%)
OR (95%CI)c
Controls N(%)
Cases N(%)
OR (95%CI)c

Phenacetin






Never
421 (92.3)
313 (85.5)
1.0 (reference)



Ever
35 (7.7)
53 (14.5)
2.2 (1.3–3.8)



Duration of used






≤ 4 yrs
14 (3.1)
22 (6.0)
2.2 (1.0–4.7)



4–8 yrs
9 (2.0)
6 (1.6)
1.1 (0.4–3.5)



>8 yrs
12 (2.6)
25 (6.8)
3.0 (1.4–6.5)



P for linear trende


0.005



Paracetamol






Never
398 (87.3)
335 (91.5)
1.0 (reference)
249 (89.6)
211 (90.9)
1.0 (reference)
Ever
58 (12.7)
31 (8.5)
0.7 (0.4–1.2)
29 (10.4)
21 (9.1)
0.8 (0.5–1.6)
Duration of used






≤ 4.5 yrs
19 (4.2)
12 (3.3)
0.9 (0.4–1.9)
12 (4.3)
8 (3.4)
0.8 (0.3–2.0)
4.5–16 yrs
19 (4.2)
13 (3.6)
0.9 (0.4–1.9)
10 (3.6)
9 (3.9)
0.9 (0.4–2.5)
>16 yrs
20 (4.4)
6 (1.6)
0.4 (0.2–1.2)
7 (2.5)
4 (1.7)
0.8 (0.2–3.1)
P for linear trende


0.116


0.672

a Model adjusted by age, sex, number of cigarettes smoked per day, and use of other NSAIDs and analgesics

b Model adjusted by age, sex, and number of cigarettes smoked per day

c Excluded 3 subjects missing number of cigarettes smoked per day.

d Based on tertile of duration of use among controls. No medication use is referent.

e Tests for trend were performed by including a single term for categorical duration of medication use using non-users as the reference category.

Fortuny et al. BMC Urology 2007 7:13   doi:10.1186/1471-2490-7-13