Table 9.

Crossover analysis of CYP27A1 methylation levels and 1,25-dihydroxyvitamin D levels in the risk of TB

1,25(OH)2Da	Cumulative methylation levelb	Cases	Controls	OR	95% CI
Low	High	23	50	0.30	0.14–0.66
High	High	21	42	0.33	0.15–0.73
Low	Low	52	9	3.78	1.48–9.62
High	Low	26	17	1
ORinteraction = 4.11 (95% CI 1.26–13.36, P = 0.019)

^aCutoff point of 1,25(OH)₂D 86 pmol/L

^bCutoff point of cumulative methylation level of CYP27A1 0.48