|
Table 3.
Logistic regression model* to identify
determinants of prevalence of antibodies to hepatitis C virus in
injecting drug users
|
|
|
Injecting drug users (n=509) |
No (%)
positive for antibodies to hepatitis C virus (n=414) |
Odds
ratio (95% CI) |
P value |
|
| Months spent in
prison over past 10 years: |
| <3 |
40 |
19
(47.5) |
1 |
|
| 3-11 |
49 |
36
(73.5) |
2.3 (0. 8 to 7.1) |
0.14 |
| 12-36 |
120 |
97
(80.8) |
2.4 (0.9 to 6.6) |
0.08 |
| >36 |
296 |
260 (87.8) |
2.9
(1.1 to 7.6) |
0.03 |
| Years since first injecting: |
| <3 |
85 |
55
(64.7) |
1 |
|
 3 |
383 |
327
(85.40 |
2.9 (1.5 to 5.4) |
0.001 |
| Sharing needles in prison: |
| No |
145 |
90
(62.1) |
1 |
|
| Yes |
347 |
314
(90.5) |
2.9 (1.5 to 5.7) |
0.002 |
| No of
times injected in month before survey: |
| 0 |
221 |
177
(80.1) |
1 |
|
| 1-19 |
139 |
119
(85.6) |
1.1 (0.5 to 2.1) |
0.89 |
| 20 |
74 |
67
(90.5) |
3.0 (1.1 to 10.0) |
0.05 |
|
Whole model  2=53, P<0.0001.
|
|
*
Initial model included variables age, sex, time spent in prison
in preceding 10 years, smoking heroin, length of time since first
injection, started injecting in prison, sharing practices in prison and
outside prison, injecting frequency in prison, taking methadone before
committal, ever had sex with a man inside or outside prison, ever
treated for sexually transmitted infection, and use of condoms during
heterosexual intercourse. Significant factors were retained in final
model. Interaction between length of time spent in prison in past 10 years and number of years since first injecting drugs was not
significant.
|
|
Numbers do not always add up to total because not all
respondents answered all questions.
|