Table 4.

Regression analysis of the association between drug addiction features and candidate SNPs of OPRK1 gene

SNP ID	Covariate	Regression coefficients B B vs Expected. B*		P-value**
rs12675595	Age	0.30	1.35	0.01
	Smoking	−1.25	0.28	< 0.0001
	Work	0.18	1.19	0.28
	Marital status	−0.98	0.37	< 0.0001
	GG	0.41	1.51	0.53
	AG	0.36	1.44	0.59
	AA	reference
rs1051660	Age	−0.30	.735	0.01
	Smoking	1.25	3.515	< 0.0001
	Work	−0.18	.828	0.26
	Marital status	0.97	2.656	< 0.0001
	CC	0.20	1.223	0.730
	CA	0.32	1.390	0.581
	AA	reference
rs6985606	Age	−0.30	0.73	0.01
	Smoking	1.24	3.46	< 0.0001
	Work	−0.16	0.84	0.32
	Marital status	0.96	2.62	< 0.0001
	CC	0.03	1.03	0.86
	CT	−0.01	0.98	0.96
	TT	reference
rs997917	Age	− 0.29	0.74	0.01
	Smoking	1.26	3.55	< 0.0001
	Work	−0.17	0.84	0.30
	Marital status	0.94	2.56	< 0.0001
	CC	−0.20	0.81	0.28
	CT	−0.25	0.77	0.10
	TT	reference
rs702764	Age	−0.31	0.73	0.01
	Smoking	1.26	3.55	< 0.0001
	Work	−0.17	0.84	0.30
	Marital status	0.97	2.64	< 0.0001
	CC	−0.09	0.91	0.78
	CT	−0.15	0.86	0.31
	TT	reference
rs963549	Age	−0.30	0.73	0.01
	Smoking	1.26	3.54	< 0.0001
	Work	−0.18	0.83	0.28
	Marital status	0.96	2.61	< 0.0001
	CC	0.01	1.01	0.97
	CT	−0.09	0.90	0.78
	TT	reference

* Beta coefficients

** P-Value < 0.05 is considered as significant