Table 1 Summary of studies included in the meta-analysis
From: Vitamin D and the risk of latent tuberculosis infection: a systematic review and meta-analysis
Study [Reference] | Country | Study design | Population | Total number of participants | Number of LTBI cases | Median/Mean age, years (IQR/SD) | Female, n (%) | Method of Measuring Vitamin D | Median baseline 25-OH Vitamin D, nmol/L(ng/ml) (IQR/SD) | Length of follow- up | LTBI disease definition | Effect estimate (95% CI) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Maceda 2018 [24] | Brazil | Nested case–control study | Over 18 years old Brazilian prisoners | 90 | 30 | Cases: 32.1 (6.87) Controls: 31.1 (7.71) | NR | ECLIA | Cases: 37.7 (11.93) Controls: 34.5 (14.89) | 1 year | Smear and/or culture positive | OR for vitamin D and TST, ≥ 30 ng/ml compared with < 30 ng/ml: 1.27 (0.48–3.38) |
Arnedo-Pena 2011 [25] | Spain | Cross-sectional and case–control study | Contacts of TB patients | 93 | 11 | Cases: 39.6 (13.1) Controls: 34.7 (14.5) | Cases: 3 (29.3) Controls: 41 (50.0) | ECLIA | Cases: 17.5 (5.6) Controls: 25.9 (13.7) | 2 months | The change from negative to positive TST with an increase of ≥ 5 mm on the induration in non BCG-vaccinated participants, and an increase of ≥ 10 mm on the induration from the initial TST, or the presence of vesicles in BCG-vaccinated participants | OR for vitamin D and TST, ≥ 30 ng/ml compared with < 30 ng/ml: 0.10 (0.01–1.73) |
Arnedo-Pena 2020 [17] | Spain | Cross-sectional and prospective cohort study | Exposed population of TB cases | 837 | 166 | Cases: 79 (range 24–95) Non-cases: 56 (range 18–105) | Cases: 100 (60.2) Non-cases: 521 (77.6) | CLIA | Cases: 18.6 (13.4) Non-cases: 19.6 (12.8) | 8–10 weeks | QFT, interferon-gamma release assay or TST positive and chest radiography | RR for vitamin D and LTBI, ≥ 30 ng/ml compared with < 30 ng/ml: 0.48 (0.16–1.40) |
Arnedo-Pena 2015 [16] | Spain | Prospective cohort study | Contacts of pulmonary TB patients | 198 | 18 | Cases: 32.8 (17.2) Non-cases: 38.1 (12.4) | Cases: 6 (33.3) Non-cases: 92 (51.1) | CLIA | Cases: 20.7 (11.9) Non-cases: 27.2 (11.4) | 8–10 weeks | A change from negative QFT-GIT in the first test to positive QFT-GI in the second test with an increase of at least 2.6 times the first QFT-GIT test (LTBI); and thorax radiology | a RR for vitamin D and LTBI, ≥ 30 ng/ml compared with < 30 ng/ml: 0.22 (0.07–0.70) |
Verrall 2017 [26] | Indonesia | Prospective cohort study | Household case contacts | 298 | 76 | Cases: 40 (15) Non-cases: 40 (15) | Cases: 110 (49.5) Non-cases: 43 (56.6) | ID-LC–MS/MS | 54.1 (21.5) nmol/L | 14 weeks | Quantiferon Gold In Tube (QFN-GIT) tested positive (LTBI) | a RR for vitamin D and LTBI, ≥ 30 ng/ml compared with < 30 ng/ml: 1.29 (0.73–2.30) |