Table 1:
Baseline characteristics of mother–infant pairs included in the analysis
| Immediate isoniazid preventive therapy (n=369) | Deferred isoniazid preventive therapy (n=380) | |
|---|---|---|
| Maternal characteristics | ||
| Country | ||
| Botswana (2 sites) | 53 (14%) | 54 (14%) |
| Haiti (1 site) | 6 (2%) | 9 (2%) |
| India (1 site) | 9 (2%) | 10 (3%) |
| South Africa (3 sites) | 59 (16%) | 53 (14%) |
| Tanzania (1 site) | 29 (8%) | 32 (8%) |
| Thailand (1 site) | 13 (4%) | 17 (4%) |
| Uganda (1 site) | 59 (16%) | 60 (16%) |
| Zimbabwe (3 sites) | 141 (38%) | 145 (38%) |
| Age at entry, years | 29 (25 to 34) | 29 (24 to 33) |
| CD4 count, cells per mm3 | 491 (348 to 670) | 499 (350 to 693) |
| Undetectable HIV-1 RNA | 229 (62%) | 236 (62%) |
| IGRA result | ||
| Positive* | 106 (29%) | 117 (31%) |
| Negative | 233 (63%) | 233 (61%) |
| Indeterminate | 23 (6%) | 25 (7%) |
| Unknown | 7 (2%) | 5 (1%) |
| TST result at delivery (or up to 6 weeks postpartum) | ||
| Positive† | 48 (13%) | 52 (14%) |
| Negative | 301 (82%) | 309 (81%) |
| Unknown | 20 (5%) | 19 (5%) |
| Completed entire isoniazid regimen | 336 (91%) | 339 (89%) |
| Duration of isoniazid therapy, weeks | 28 (27 to 29) | 28 (27 to 28) |
| Infant characteristics | ||
| Sex Female |
189 (51%) | 188 (49%) |
| Male | 180 (49%) | 192 (51%) |
| HIV positive‡ | 2 (1%) | 5 (1%) |
| Reported tuberculosis exposure§ | 10 (3%) | 10 (3%) |
| Timing of tuberculosis exposure, study week | 28·5 (11 to 41) | 30 (17 to 39) |
| BCG vaccination status (scar or record of receipt) | 344 (93%) | 350 (92%) |
| BCG scar present | 299 (81%) | 304 (80%) |
| Documented record of receipt | 242 (66%) | 260 (68%) |
| WHO weight-for-age Z score | ||
| Mean | −0·3 (2·8) | −0·5 (1·2) |
| Median | −0·5 (−1·3 to 0·3) | −0·5 (−1·4to 0·3) |
| Exclusive breastfeeding for any duration | 303 (82%) | 297 (78%) |
| Exclusive breastfeeding duration¶ | ||
| Mean (SD), weeks | 23·0 (12·9) | 21·9 (13·1) |
| Median (IQR), weeks | 30 (17 to 30) | 30 (10 to 30) |
| 0 week | 66 (18%) | 83 (22%) |
| >0–12 weeks | 20 (5%) | 17 (4%) |
| >12–24 weeks | 43 (12%) | 31 (8%) |
| >24–36 weeks | 212 (57%) | 235 (62%) |
| >36 weeks | 28 (8%) | 14 (4%) |
| Timing of tuberculosis tests | ||
| TST before IGRA blood draw (≥7 days) | 7 (2%) | 9 (2%) |
| TST after IGRA blood draw | 350 (95%) | 366 (96%) |
| IGRA not performed | 12 (3%) | 5 (1%) |
Data are n (%) median (IQR), unless otherwise indicated. Some percentages do not sum to 100 due to rounding. BCG=Bacille Calmette-Guérin. IGRA=interferon-γ release assay. TST=tuberculin skin test.
*
Defined as an interferon-γ concentration of ≥0·35 IU/mL.
†
Defined as an induration diameter ≥5 mm for mothers with HIV and ≥10 mm for mothers without HIV.
‡
Assessed at birth, at 48 weeks after delivery, and at the time of suspected tuberculosis disease.
§
14 exposures were household contacts, including five maternal exposures, and six were non-household contacts.
¶
Calculated as the time from birth to the last study visit where breastfeeding was reported.