Table 6.
Results of Multiple Logistic Regression Models (Backward Elimination)†
| β | OR | 95% CI | P | |
|---|---|---|---|---|
| Medical/Family history | ||||
| Family history of PBC | 1.1868 | 10.736 | 4.227–27.268 | <.0001 |
| Family history of SLE | 0.4019 | 2.234 | 1.261–3.957 | .0059 |
| Family history of Sjögren | 0.8801 | 5.814 | 1.279–26.435 | .0227 |
| History of urinary tract infections | 0.2065 | 1.511 | 1.192–1.915 | .0006 |
| Lifestyle factors | ||||
| Ever smoked >100 cigarettes | 0.2252 | 1.569 | 1.292–1.905 | <.0001 |
| No passive smoke at work/ | −0.2368 | 0.820 | 0.582–1.155/ | |
| Does not have a job | 0.2574 | 1.369 | 1.095–1.712 | .0005 |
| Uses of nail polish/year | 0.00177 | 1.002‡ | 1.000–1.003 | .0136 |
| Number of cigarettes smoked | −0.00109 | 0.999 | 0.998–1.000 | .0031 |
| Each smoker in household | −0.6776 | 0.5078 | 0.3167–0.8143 | .0041 |
| Reproductive history* | ||||
| Ever used hormonal replacement | 0.2185 | 1.548 | 1.273–1.882 | <.0001 |
| Never pregnant | −0.4906 | 0.6118 | 0.4489–0.8338 | .0012 |
| Age of first pregnancy | −0.0470 | 0.9541 | 0.9331–0.9755 | <.0001 |
†
In all the models used, household income was significantly correlated with PBC (P < .0001).
‡
Calculated for each additional use of nail polish/year.
*
For female cases and controls only.