Table 2. Univariate and multivariate analysis for QFT positivity.
| n/N (%) | p for χ2 test | Adjusted OR* (95% CI) | |
|---|---|---|---|
| Study sites | <0.0001 | ||
| Site A | 1052/5014(20.98) | Reference | |
| Site B | 801/4141(19.34) | 1.03(0.90–1.17) | |
| Site C | 1173/4213(27.84) | 1.34(1.19–1.51) | |
| Site D | 847/3896(21.74) | 1.37(1.21–1.56) | |
| Gender | <0.0001 | ||
| Female | 1793/9415(19.04) | Reference | |
| Male | 2080/7849(26.50) | 1.29(1.15–1.44) | |
| Age (years) | <0.0001 | ||
| 18–29 | 194/2344(8.28) | Reference | |
| 30–39 | 313/2116(14.79) | 1.81(1.47–2.22) | |
| 40–49 | 876/4513(19.41) | 2.46(2.04–2.96) | |
| 50–59 | 934/3479(26.85) | 3.81(3.16–4.58) | |
| 60–69 | 966/3047(31.70) | 4.97(4.10–6.04) | |
| ≥70 | 590/1765(33.43) | 5.67(4.61–6.98) | |
| Education level | <0.0001 | ||
| Primary school or lower | 2175/8573(25.37) | Reference | |
| Middle school | 1264/6044(20.91) | 1.10(1.00–1.21) | |
| High school | 367/2014(18.22) | 1.06(0.92–1.22) | |
| College or higher | 67/633(10.58) | 0.95(0.71–1.26) | |
| Smoking status | <0.0001 | ||
| Never smoked | 2405/12176(19.75) | Reference | |
| Ever smoked | 1468/5086(28.86) | 1.28(1.15–1.43) | |
| Alcohol drinking | <0.0001 | ||
| No | 2877/13373(21.51) | Reference | |
| Yes | 996/3890(25.60) | 0.99(0.89–1.10) | |
| History of close contact with TB patients | <0.0001 | ||
| No | 3480/15826(21.99) | Reference | |
| Yes | 221/708(31.21) | 1.38(1.16–1.64) | |
| History of T2DM | |||
| No | 3627/16396(22.12) | Reference | |
| Yes | 246/868(28.34) | 1.04(0.88–1.22) | |
| Number of BCG scars | |||
| 0 | 2021/8891(22.73) | Reference | |
| 1 | 1049/5030(20.85) | 0.98(0.88–1.10) | |
| ≥2 | 803/3341(24.03) | 1.05(0.93–1.20) | |
| Cholesterol levela | <0.0001 | ||
| Normal | 3168/14632(21.65) | Reference | |
| Higher than normal | 704/2628(26.79) | 1.04(0.92–1.19) | |
| Triglyceride levelb | <0.0001 | ||
| Normal | 2380/11072(21.50) | Reference | |
| Higher than normal | 1492/6188(24.11) | 1.04(0.96–1.13) | |
| LDL levelc | <0.0001 | ||
| Normal | 3117/14538(21.44) | Reference | |
| Higher than normal | 754/2721(27.71) | 1.12(1.03–1.16) | |
| HDL leveld | 0.9913 | ||
| Normal | 3420/15246(22.43) | ||
| Higher than normal | 452/2014(22.44) | ||
| BMI (kg/m2) | 0.0028 | ||
| <18.5 | 168/908(18.50) | 0.80(0.66–1.01) | |
| 18.5–24.0 | 1987/9046(21.97) | Reference | |
| 24.0–28.0 | 1254/5350(23.44) | 1.07(0.98–1.17) | |
| ≥28.0 | 464/1960(23.67) | 1.15(1.01–1.31) | |
Abbreviations: BMI = body mass index. BCG = Bacillus Calmette-Guerin. CI = confidence interval. HDL = high density lipoprotein. LDL = low density lipoprotein. OR = odds ratio. QFT = QuantiFERON-TB Gold In-Tube. TB = tuberculosis. T2DM = type 2 diabetes mellitus.
*Controlling for variables with p < 0.05 in the univariate analysis.
a,b,c,dRanges of normal value for blood tests in different study sites: Cholesterol: Site A = 2.59–5.17 mmol/L, Site B = 3.1–5.17 mmol/L, Site C = 0–5.17 mmol/L, Site D = 0–5.17 mmol/L. Triglyceride: Site A = 0–1.7 mmol/L, Site B = 0.56–1.7 mmol/L, Site C = 0–1.71 mmol/L, Site D = 0–2.3 mmol/L. HDL: Site A = >0.9 mmol/L, Site B = 0.9–2.28 mmol/L, Site C = 1.16–1.55 mmol/L, Site D = 1.05–1.74 mmol/L. LDL: Site A = 0–4.11 mmol/L, Site B = 0–3.36 mmol/L, Site C = 0–3.12 mmol/L, Site D = <3.1 mmol/L.