The impact of smoking on clinical features of Behcet's disease patients with glutathione S-transferase polymorphisms

Objective. Various cancer studies have suggested that polymorphism of GSTM1 may influence the ability to detoxify chemicals in. cigarette smoke. In the present study the effect of smoking on clinical features of Behcet's disease were investigated in patients having GST-M1 and/or -T1 null polymorphisms. Methods. Ninety-seven patients meeting International Study Group Criteria for Behcet Disease (63 male, 34 female) and 172 healthy controls (94 male, 78 female) were included into the study. GST-M1 and -T1 polymorphisms were investigated using polymerase chain reaction-restriction fragment length polymorphism technique. Results. Frequency of GSTM1- and/or GSTT1-null polymorphisms were comparable between the Behcet and the control groups. Smoking patients with GSTM1 null-polymorphism have decreased risk of developing papulopustuler lesions (OR=0.227 [0.063-0.818], chi(2)=5.463, p=0.019). Non-smoking patients with GSTM1 null-polymorphism has increased risk for having chronic arthritis (OR=5.988 [0.845-43.478]) but smoking patients with GSTM1 null-polymorphism have decreased risk (OR=0.741 [0.593-0.926]). GSTM1 null-polymorphism is associated with the presence of venous insufficiency (chi(2)=6 273, p=0.012, OR=2.740 [1.224-6.135]); smoking further increases the risk (chi(2)=7.840, OR=3 333 [1.412-7.874], p=0.005). GSTM1 null-polymorphism seemed to effect development of large vessel vasculitis (OR=1.158 [0.981-1367], chi(2)=4.760, p=0.029). Male smoker Behcet patients even have more risk (OR=1 250 [0.971-1.610]). Conclusion. Several manifestations of Behcet's disease may be influenced by smoking, and this effect can be augmented in patients carrying GST gene polymorphism, which code enzymes crucial for the detoxification of chemicals.