Table 2.
Risk factors associated with the incidence of latent tuberculosis infection in prisoners over 2 years of follow-up in two prisons in Colombia, 2013–2015
| Variable | Crude relative risk | 95% confidence interval | Adjusted relative risk | 95% confidence interval | ||
|---|---|---|---|---|---|---|
| Lower limit | Upper limit | Lower limit | Upper limit | |||
| No contact | 1·00 | – | – | 1·00 | – | – |
| Contact with a prisoner with TB prior to TST administration | 0·94 | 0·85 | 1·03 | 0·53 | 0·27 | 1·03 |
| No BCG scar | 1·00 | – | – | 1·00 | – | – |
| BCG scar | 0·89 | 0·83 | 0·96 | 0·96 | 0·60 | 1·55 |
| Prison 2 | 1·00 | – | – | 1·00 | – | – |
| Prison 1 | 10·2 | 9·14 | 11·4 | 11·66 | 1·65 | 82·18 |
| Being formerly incarcerated | 12* | 10·48 | 13·74 | 17·27 | 2·44 | 121·94 |
| No smoking | 1·00 | – | – | 1·00 | – | – |
| Smoking | 1·35 | 0·64 | 2·83 | 1·02 | 0·60 | 1·73 |
| Duration of incarceration at time of TST administration >36 months | 1·00 | – | – | 1·00 | – | – |
| Duration of incarceration at time of TST administration ⩽36 months | 1·66 | 0·54 | 5·09 | 0·99 | 0·61 | 1·59 |
| Age >36 years | 1·00 | – | – | 1·00 | – | – |
| Age ⩽35 years | 1·28 | 0·84 | 1·96 | 1·20 | 0·55 | 2·59 |
| No overweight† | 1·00 | – | – | 1·00 | – | – |
| Overweight† | 1·15 | 0·72 | 1·84 | 1·61 | 1·05 | 2·47 |
| Prior incarceration | 0·75 | 0·34 | 1·63 | 0·64 | 0·24 | 1·67 |
TB, tuberculosis; TST, tuberculin skin test; BCG, bacillus Calmette–Guérin vaccine.
*
All positive TST converters were incarcerated in prison 1.
†
Body mass index ⩾25 kg/m2.
Variables included in the model: age, contact with a prisoner with TB prior to TST administration, overweight, current place of incarceration, smoking, duration of incarceration at time of TST administration, BCG scar and prior incarceration.