. 2016 Jun 17;13(6):601. doi: 10.3390/ijerph13060601

Table 4.

Interaction effects of the MTHFR C677T polymorphism with age, sex, BMI, drinking, and smoking status on hypertension susceptibility.

Genotype	Demographic and Lifestyle Factor	Adjusted OR * (95% CI)	p-Value	RERI (95% CI)	p-Value
Age
CC	≤45	1.0 (reference)		1.26 (−0.33–2.85)	0.103
CT + TT	≤45	1.46 (0.69–3.12)	0.325
CC	>45	2.36 (1.02–5.47)	0.045
CT + TT	>45	4.08 (1.95–8.54)	<0.001
Sex
CC	Female	1.0 (reference)		−0.27 (−2.85–2.32)	0.818
CT + TT	Female	2.77 (0.77–9.99)	0.119
CC	Male	2.98 (0.82–10.85)	0.098
CT + TT	Male	4.48 (1.29–15.55)	0.018
BMI
CC	Normal weight	1.0 (reference)		1.33 (−0.15–2.80)	0.084
CT + TT	Normal weight	1.34 (0.56–3.19)	0.506
CC	Overweight/obesity	2.23 (0.91–5.48)	0.079
CT + TT	Overweight/obesity	3.90 (1.74–8.72)	0.001
Drinking status
CC	Non-drinkers	1.0 (reference)		0.40 (−0.92–1.72)	0.569
CT + TT	Non-drinkers	1.63 (0.89–2.97)	0.111
CC	Ever-drinkers	1.59 (0.72–3.55)	0.255
CT + TT	Ever-drinkers	2.62 (1.39–4.96)	0.003
Smoking status
CC	Non-smokers	1.0 (reference)		−0.88 (−2.51–0.75)	0.271
CT + TT	Non-smokers	2.07 (1.17–3.65)	0.012
CC	Ever-smokers	1.70 (0.74–3.88)	0.211
CT + TT	Ever-smokers	1.88 (1.04–3.42)	0.038

Abbreviations: MTHFR, methylenetetrahydrofolate reductase; BMI, body mass index; OR, odds ratio; CI, confidence interval; RERI, relative excess risk due to interaction. * Joint ORs for age and genotype was adjusted by sex, BMI, drinking and smoking status; joint ORs for gender and genotype was adjusted by age, BMI, drinking and smoking status; joint ORs for BMI and genotype were adjusted by age, sex, drinking, and smoking status; joint ORs for drinking status and genotype was adjusted by age, sex, BMI and smoking status; joint ORs for smoking and genotype were adjusted by age, sex, and drinking status. p-Value < 0.05 was considered statistically significant.