Interaction of the glutathione S-transferase genes and cigarette smoking on risk of lower extremity arterial disease: the Atherosclerosis Risk in Communities (ARIC) study.
Glutathione S-transferases M1 or T1 (GSTM1/GSTT1) affect the body's ability either to detoxify or to activate chemicals in cigarette smoke. Cigarette smoking increases the risk of lower extremity arterial disease (LEAD). We conducted a cross-sectional study to evaluate a hypothesized interaction of the genetic polymorphisms of GSTM1 and T1 with cigarette smoking in the risk of LEAD in the ARIC study. A stratified-random sample, including 212 LEAD cases (ankle-brachial index <0.9 in men or <0.85 in women) and 1277 non-cases, was selected from the ARIC cohort of 12041 middle-aged participants free of CHD, transient ischemic attack and stroke at baseline (1987-1989). Overall, the differences in the frequencies of GSTM1-0 and GSTT1-0 (the homozygous deletion genotype) were not statistically significant between cases and non-cases (44 vs. 41% and 28 vs. 18%). However, smoking was more prevalent among LEAD cases than non-cases. The results suggest that the non-deletion genotype GSTM1-1 interacts with smoking to increase the risk of LEAD, but this interaction was not statistically significant. The functional genotype GSTT1-1 was significantly associated with increased risk of LEAD given smoking after adjustment for other risk factors. In individuals with GSTT1-1, the odds ratios (ORs) (95% confidence intervals) of LEAD were 3.6 (1.4, 9.0) for current smoking and 5.0 (1.9, 13.0) for 20+ pack-years. However, in those with GSTT1-0, the ORs were 0.8 (0.2, 2.8) for current smoking and 0.6 (0.1, 2.1) for 20+ pack-years. The interaction was significant (P<0.05) on the additive scale for current smoking and on both the additive and multiplicative scales for 20+ pack-years. Among non-smokers, GSTT1-1 was not associated with LEAD. The results suggest that the GSTT1-1 polymorphism may be a susceptibility factor modifying the risk of LEAD associated with cigarette smoking.
Department of Epidemiology, University of North Carolina at Chapel Hill, Suite 306, Bank of America Center, 137 E. Franklin Street, Chapel Hill, NC 27514, USA.
R
R
Li
A R
AR
Folsom
A R
AR
Sharrett
D
D
Couper
M
M
Bray
H A
HA
Tyroler
D001161:Arteriosclerosis / Q000209:etiology* / Q000235:genetics*; D003430:Cross-Sectional Studies; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D005982:Glutathione Transferase / Q000235:genetics*; D006801:Humans; D007866:Leg / Q000098:blood supply*; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects*
D005982:Glutathione Transferase; C413545:glutathione S-transferase T1