Table 2.
Disease/exposure | Exposure to IPT | Total | p value | ||
---|---|---|---|---|---|
No (on ART only) | Yes (IPT and ART) | ||||
Development of tuberculosis | No | 970 (78.1%) | 593 (95.5%) | 1563 (83.9%) | <0.0001 |
Yes | 272 (21.9%) | 28 (4.5%) | 300 (16.1%) | ||
Total | 1242 (100.0%) | 621 (100.0%) | 1863 (100.0%) | <0.0001 | |
Incidence rate of TB (per 100,000 persons-years) | 3160 | 620 |
On average, the time to development of TB incidence post-IP exposure was 926 days (two and half years). The incidence rate of TB (per 100,000 PYs) was 620 (incidence rate difference = −2250; 95% CI: −3000 to −2110; p value < 0.0001) for the exposed groups and 3160 (incidence rate ratio = 2340; 95% CI: 1530 to 3470) for the unexposed groups (Table 2). The KM analysis for the incidence of TB illustrated that unexposed patients had more chance of developing TB than exposed patients (p < 0.0001) (Figure 2).