Table 3—

Proportion of tuberculin skin tests(TST) ≥ 10 mm and positive interferon-γ release assay (IGRA), and the respective adjusted OR and 95% CI for different putative risk factors

TST ≥10mmIGRA-positive
n (%)OR95% CIn (%)OR95% CI
Age
 16–29 yrs212 (47.9)199 (22.3)1
 30–39 yrs146 (43.5)0.90.68–1.23100 (29.8)1.40.97–1.91
 40–49 yrs88 (41.5)1.00.68–1.3887 (41.0)1.81.26–2.70
 50–59 yrs78 (39.2)1.10.71–1.5699 (49.7)2.11.40–3.17
 ≥60 yrs8 (28.6)0.70.23–1.6812 (42.9)1.40.63–3.28
Sex
 Female391 (44.5)1278 (31.7)1
 Male141 (41.5)1.00.77–1.31119 (35.0)0.90.70–1.24
BCG vaccination
 Only at birth131 (35.4)1166 (44.9)1
 1 additional186 (43.7)1.41.02–1.82137 (32.2)0.80.60–1.12
 2 additional149 (49.5)1.61.18–2.2474 (24.6)0.80.55–1.18
 3–10 additional66 (54.5)2.01.29–3.0220 (16.5)0.60.34–1.07
Years since last BCG
 >15 yrs373 (40.5)1355 (38.6)1
 >10–15 yrs119 (52.4)1.30.91–1.8036 (15.9)0.40.28–0.67
 1–10 yrs40 (56.3)1.40.84–2.386 (8.5)0.20.09–0.52
Profession
 Administrator76 (40.9)175 (40.3)1
 Auxiliaries, cleaning staff65 (34.6)0.70.49–1.1376 (40.4)1.50.95–2.45
 Technicians (radiology, lab, etc.)44 (51.8)1.40.82–2.3422 (25.9)0.80.43–1.45
 Nurses276 (50.4)1.30.91–1.82138 (25.2)0.80.52–1.21
 Physicians71 (33.6)0.70.45–1.0286 (40.8)1.60.98–2.54
Risk assessment
 Low risk69 (39.9)173 (42.2)1
 Moderate risk177 (43.5)1.20.77–1.79143 (35.1)0.90.59–1.41
 High risk286 (44.8)1.10.77–1.72181 (28.4)0.70.46–1.07
Time working in healthcare
 Start of work83 (39.9)143 (20.7)1
 <5 yrs142 (47.2)1.20.81–1.7280 (26.6)1.71.08–2.69
 5–<10 yrs102 (48.1)1.20.81–1.8358 (27.4)1.81.08–2.86
 10–<15 yrs65 (45.8)1.10.73–1.7852 (36.6)2.91.34–4.87
 15–<20 yrs36 (40.0)0.90.56–1.5839 (43.3)3.01.68–5.26
 ≥20 yrs104 (39.2)1.20.79–1.79125 (47.2)2.61.64–4.13
  • BCG: bacillus Calmette–Guérin