Table 5.
Difference in forced vital capacity by serum 25(OH)D quartile according to evidence of PTB
| Variable | 25(OH)D (quartile) |
P for trend | |||
|---|---|---|---|---|---|
| Q1 | Q2 | Q3 | Q4 | ||
| Non-PTB (mL) | |||||
| Crude | Ref | 22.0±16.0 | 24.0±16.0 | 38.0±16.0 | 0.122 |
| Model 1 | Ref | 20.4±16.2 | 25.2±15.8 | 39.6±16.2* | 0.015 |
| Model 2 | Ref | 20.5±16.2 | 25.1±15.7 | 39.4±16.2* | 0.016 |
| Model 3 | Ref | 15.4±16.1 | 19.5±15.7 | 31.2±16.0 | 0.052 |
| Past PTB (mL) | |||||
| Crude | Ref | 75.0±46.0 | 66.0±45.0 | 88.0±48.0 | 0.502 |
| Model 1 | Ref | 62.0±45.8 | 48.5±44.3 | 69.3±47.7 | 0.203 |
| Model 2 | Ref | 61.2±45.8 | 51.7±44.4 | 69.4±47.0 | 0.186 |
| Model 3 | Ref | 55.2±45.1 | 53.2±44.4 | 73.3±46.1 | 0.141 |
Values are presented as the mean±standard error. Model 1 was adjusted for age, sex, height, and season; model 2 was adjusted for the same variables as in model 1 with additional adjustment for smoking and exercise; model 3 was adjusted for the same variables as in model 2 with additional adjustment for body mass index, occupation, and region. Q1, <15.1 ng/mL; Q2, 15.1–19.1 ng/mL; Q3, 19.1–23.9 ng/mL; and Q4, ≥23.9 ng/mL for men. Q1, <12.7 ng/mL; Q2, 12.7–16.1 ng/mL; Q3, 16.1–20.5 ng/mL; and Q4, ≥20.5 ng/mL for women. The data were analyzed by multiple linear regression with the Bonferroni post-hoc test and are shown as the mean and standard error in mL.
25(OH)D, 25-hydroxyvitamin D; PTB, pulmonary tuberculosis; Q, quartile; Ref, reference.
P<0.05, compared with the lowest vitamin D quartile (Q1).