Table 1 Characteristics of study participants.

From: Immunological correlates of mycobacterial growth inhibition describe a spectrum of tuberculosis infection

 

State of infection

P values

Active TB

LTBI

Controls

P1

P2

P3

n = 21 (%)

n = 139 (%)

n = 51 (%)

Mean age (yrs) [IQR]

33.4 [22.5–44]

23.7 [19–28.5]

24.1 [19.4–27]

<0.0001

0.0065

0.54

Gender male

16 (76.2)

107 (77.0)

38 (74.5)

0.9966

0.9874

0.9339

Place of birth

UK

9 (42.9)

15 (10.8)

18 (35.3)

0.0008

0.5985

0.0002

Outside UK

12 (57.1)

124 (89.2)

33 (64.7)

—

—

—

Ethnic group

White Caucasian

2 (9.5)

8 (5.8)

18 (35.3)

0.6216

0.0409

0.0001

Sub-Saharan African

4 (19.0)

23 (16.5)

1 (2.0)

0.7580

0.0233

0.0057

Indian subcontinent

13 (61.9)

99 (71.2)

32 (62.7)

0.4452

1.0

0.2906

Other

2 (9.5)

9 (6.5)

0

0.6393

0.0822

0.1159

BCG vaccinated

20 (95.2)

111 (79.9)

31 (60.8)

0.1275

0.0036

0.0135

Culture confirmed TB

8 (38.1)

NA

NA

—

—

—

System

Pulmonary

15 (71.4)

NA

NA

—

—

—

Extrapulmonarya

5 (23.8)

NA

NA

—

—

—

Miliary

1 (4.8)

NA

NA

—

—

—

Completed treatment

21 (100)

131 (94.2)b

NA

0.5982

—

—

Post-treatment samples

12 (57.1)

78 (56.1)

NA

1.0

—

—

  1. Two-tailed P values were calculated by Fisher’s exact test between infection states as follows: P1 = Active TB vs LTBI; P2 = Active TB vs Healthy controls; P3 = LTBI vs Healthy controls.
  2. aExtrapulmonary TB included four lymph node TB and one bone TB.
  3. bn = 8 (5.8%) participants with LTBI were untreated due to the following reasons: n = 4 were >35 years of age; n = 3 were pregnant; n = 1 reported drug intolerance shortly after commencing therapy.
  4. LTBI = latent TB infection; IQR = interquartile range; NA = not applicable.
Back to article page