Early proactive monitoring of DNA-thioguanine in patients with Crohn’s disease predicts thiopurine-induced late leucopenia in NUDT15/TPMT normal metabolizers

Table 2 Univariate and multivariate analysis of independent predictors for leucopenia

Characteristics	Univariate analysis		Multivariate analysis
	HR (95%CI)	P value	HR (95%CI)	P value
Age (yr)	1.04 (1.01-1.08)	0.005	1.06 (1.02-1.09)	0.002
Weight (kg)	0.95 (0.91-0.99)	0.013	0.96 (0.92-1.00)	0.076
DNATG (fmol/μg DNA)	1.004 (1.002-1.005)	< 0.001	1.004 (1.002-1.005)	< 0.001
NUDT15 genotypes		< 0.001
NUDT15*1/*1	Reference		Reference
NUDT15*1/*6	17.99 (3.95-81.90)	< 0.001	11.62 (1.51-89.26)	0.018
NUDT15*1/*3	4.93 (2.41-10.10)	< 0.001	3.21 (1.54-6.71)	0.002
NUDT15*1/*2	4.50 (2.01- 10.03)	< 0.001	3.25 (1.41-7.50)	0.006
6TGN (pmol/8 × 108 RBC)	1.003 (1.001-1.004)	< 0.001	1.000 (0.998-1.002)	0.98
Sex		0.19
Female	Reference
Male	0.64 (0.34-1.22)	0.17
TPMT genotypes		0.31
TPMT*1/*1	Reference
TPMT*1/*3C	2.38 (0.57-9.87)	0.25

HR: Hazard ratio; CI: Confidence interval; NUDT15: Nudix hydrolase 15; TPMT: Thiopurine methyltransferase; 6TGN: 6-thioguanine nucleotides; DNATG: DNA-thioguanine; RBC: Red blood cell.