Prediction of Methotrexate Clinical Response in Portuguese Rheumatoid Arthritis Patients: Implication of MTHFR rs1801133 and ATIC rs4673993 Polymorphisms

Table 4

Multivariate logistic regression analysis and clinical response to methotrexate.

Genetic variables	Adjusted variables
	Patient-related		Patient-related + disease-related		Patient-related + disease-related + treatment-related
	𝑃 value	OR (95% CI)	𝑃 value	OR (95% CI)	𝑃 value	OR (95% CI)
MTHFR C677T, rs1801133
C carriers		Reference		Reference		Reference
TT	0.040	2.64 (1.04–6.67)	0.025	3.23 (1.16–9.02)	0.013	4.63 (1.37–15.60)
ATIC T675C, rs4673993
CC		Reference		Reference		Reference
T carriers	0.022	3.20 (1.18–8.66)	0.007	4.63 (1.51–14.12)	0.013	5.16 (1.42–18.76)

𝑃 value < 0.05 is considered to be of statistical significance (highlighted in bold).
Adjusted variables include (1) patient-related variables (age, gender, and smoking), (2) disease-related variables (diagnosis age, disease duration, anti-CCPs, ANAs, TJC, SJC, and HAQ), and (3) treatment-related variables (folic acid supplementation, corticosteroids therapy, use of NSAIDs, other concomitant DMARDs used and MTX administration characteristics such as dose, treatment duration, and administration route). Genetic variables include MTHFR C677T and ATIC T675C polymorphisms.
ANAs: antinuclear antibodies; anti-CCP: anti-cyclic citrullinated peptide; ATIC: 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase; C: cytosine; CI: confidence interval; HAQ: health assessment questionnaire; MTHFR: methylenetetrahydrofolate reductase; NSAIDs: nonsteroidal anti-inflammatory drugs; OR: odds ratio; SJC: swollen joints count; T: thymine; TJC: tender joints count.