NAT1 and NAT2 genetic polymorphisms and environmental exposure as risk factors for oesophageal squamous cell carcinoma: a case-control study

BMC Cancer

Table 5 Association of NAT1 acetylator phenotype with OSCC risk upon exposure to environmental risk factors in Black and Mixed Ancestry South Africans

			NAT1 rapid acetylators				NAT1 slow/intermediate acetylators
Population	Risk factors	Variables	Controls	Cases	OR (95% CI)^a	P-value	Controls	Cases	OR (95% CI)^a	P-value
Black
	Tobacco smoking	Never smokers	84	61	1 (Ref)		166	109	1 (Ref)
		Smokers^b	71	81	1.71 (0.73-4.04)	0.218	142	186	3.41 (1.95-5.96)	<0.0001
	Tot cigarettes/day	0	84	61	1 (Ref)		166	109	1 (Ref)
		≤9	45	50	1.80 (0.72-4.53)	0.208	87	123	3.96 (2.19-7.13)	<0.0001
		≥10	24	31	2.06 (0.73-5.84)	0.174	45	57	2.97 (1.47-5.99)	0.002
	Alcohol drinking	Non-drinkers	66	53	1 (Ref)		130	112	1 (Ref)
		Drinkers^c	89	89	1.17 (0.52-2.59)	0.707	177	182	0.87 (0.54-1.40)	0.570
Red meat intake ^d	3 times/week or less	−	81			−	168	1 (Ref)
		Daily or almost daily	−	12			−	23	0.93 (0.43-2.0)	0.851
	White meat intake^d	3 times/week or less	−	56			−	87	1 (Ref)
		Daily or almost daily	−	38			−	104	1.82 (1.09-3.04)	0.023
Mixed Ancestry
	Tobacco smoking	Never smokers	17	1	1 (Ref)		43	14	1 (Ref)
		Smokers^b	33	46	−	−	191	194	−	−
	Tot cigarettes/day	0	17	1	1 (Ref)		43	14	1 (Ref)
		≤9	17	24	−	−	101	58	−	−
		≥10	11	20	−	−	77	133	−	−
	Alcohol drinking	Non-drinkers	21	12	1 (Ref)		93	39	1 (Ref)
		Drinkers^c	29	35	0.80 (0.19-3.44)	0.764	140	170	3.41 (1.70-6.81)	0.001
	Red meat intake^d	3 times/week or less	−	22			−	81	1 (Ref)
		Daily or almost daily	−	7			−	42	1.32 (0.49-3.55)	0.586
	White meat intake^d	3 times/week or less	−	16			−	56	1 (Ref)
		Daily or almost daily	−	13			−	66	1.58 (0.68-3.67)	0.288

Samples with unknown acetylator status are not shown.
Ref = reference allele.
^aOR was adjusted for age, gender, smoking and alcohol consumption status; OR was not calculated for subgroups with low sample size.
^bSmokers = current and former smokers.
^cDrinkers = light to heavy alcohol drinkers.
^dCase-only analysis has been performed for red meat intake due to lack of data from control individuals.