Table 4.

Addictive interaction of important modifiers on the association between alanine aminotransferase levels and hypertension

Variables	n (%)	Crude OR (95% CI)	Multi-adjusted OR (95% CI)	RERI	AP[AB]	S
ALT & BMI*				1.393	0.322	1.720
0–40 & < 24	13,775,858 (65.28)	1	1
0–40 & ≥ 24	4,831,049 (22.89)	3.12 (3.10,3.13)	2.47 (2.46,2.49)
> 40 & < 24	1,165,030 (5.52)	1.71 (1.69,1.73)	1.46 (1.45,1.47)
> 40 & ≥ 24	1,294,200 (6.13)	5.87 (5.83,5.91)	4.23 (4.30,4.36)
ALT & Drinking†				0.214	0.093	0.377
0–40 & No	16,181,008 (76.67)	1	1
0–40 & Yes	2,439,518 (11.56)	2.23 (2.22,2.25)	1.54 (1.53,1.55)
> 40 & No	1,867,240 (8.85)	2.37 (2.36,2.39)	1.55 (1.54,1.56)
> 40 & Yes	593,887 (2.81)	4.57 (4.53,4.60)	2.31 (2.29,2.33)
ALT & Smoking†				0.014	0.078	1.195
0–40 & No	16,398,611 (77.70)	1	1
0–40 & Yes	2,225,434 (10.55)	1.90 (1.89,1.92)	1.27 (1.26,1.28)
> 40 & No	1,870,788 (8.86)	2.45 (2.44,2.47)	1.57 (1.56,1.58)
> 40 & Yes	590,777 (2.80)	3.73 (3.69,3.76)	1.86 (1.84,1.88)
ALT & HBsAg††				-0.362	-0.297	1.017
0–40 & −	17,712,079 (83.93)	1	1
0–40 & +	914,931 (4.34)	1.07 (1.06,1.08)	1.00 (0.98,1.01)
> 40 & −	2,169,086 (10.28)	2.59 (2.58,2.61)	1.58 (1.58,1.59)
> 40 & +	293,136 (1.39)	1.80 (1.77,1.83)	1.22 (1.20,1.24)

ALT: alanine aminotransferase; OR: odds ratio; BMI: body mass index; HBsAg: hepatitis B surface antigen; RERI: the relative excess risk due to interaction; AP[AB]: the proportion of disease among those with both exposures that is attributable to their interaction; S: the synergy index

n(%): n, number of participants; %, proportion of participants

*Adjusted for age, sex, ethnicity, area, education, average salt consumption, history of diabetes, overall stress and hepatitis B surface antigen status

^†Adjusted for age, sex, ethnicity, area, education, body mass index, average salt consumption, history of diabetes, overall stress and hepatitis B surface antigen status

^††Adjusted for age, sex, ethnicity, area, education, body mass index, average salt consumption, history of diabetes and overall stress