Table 3.

Impact of a) IPT and b) ART on TB incidence

	CD4≤350 N=2,138				CD4>350 N=1,976
	TB cases	Person-years	IR per 100 pys (95% CI)	IRR (95% CI)	TB cases	Person-years	IR per 100 pys (95% CI)	IRR (95% CI)
a) IPT
TST-negative / no IPT	61	5,410	1.13 (0.88–1.45)	REF	28	4,894	0.57 (0.39–0.83)	REF
TST-negative / IPT	2	137	1.46 (0.36–5.83)	1.49 (0.37–6.06)	0	127	0	—
TST-positive / no IPT	26	183	14.25 (9.70–20.92)	REF	21	268	7.83 (5.10–12.00)	REF
TST-positive / IPT	8	923	0.87 (0.43–1.73)	0.07 (0.03–0.16)	11	1,385	0.79 (0.44–1.43)	0.11 (0.06–0.21)
TST-unknown / no IPT	73	3,361	2.17 (1.72–2.73)	REF	32	3,054	1.05 (0.74–1.48)	REF
TST-unknown / IPT	0	34	0	—	0	37	0	—
b) ART
TST-negative / no ART	5	264	1.89 (0.79–4.54)	REF	21	2,758	0.76 (0.50–1.17)	REF
TST-negative / ART	58	4,890	1.19 (0.92–1.53)	0.70 (0.28–1.77)	7	1,892	0.37 (0.18–0.78)	0.49 (0.21–1.13)
TST-positive / no ART	10	53	18.95 (10.19–35.21)	REF	24	1,053	2.28 (1.52–3.40)	REF
TST-positive / ART	24	1,005	2.39 (1.60–3.56)	0.18 (0.08–0.37)	8	510	1.57 (0.79–3.14)	0.69 (0.30–1.62)
TST-unknown / no ART	17	1,445	1.18 (0.73–1.89)	REF	19	2,619	0.73 (0.46–1.14)	REF
TST-unknown / ART	56	2,391	2.34 (1.80–3.04)	1.98 (1.16–3.39)	13	934	1.39 (0.81–2.40)	1.76 (0.88–3.52)

Abbreviations: IPT, isoniazid preventive therapy; ART, antiretroviral therapy; TB, tuberculosis; IR, incidence rate; CI, confidence interval; IRR, incidence rate ratio; TST, tuberculin skin test

TST, IPT, and ART time-dependent; IRRs adjusted for sex and age at enrollment