The impact of smoking on clinical features of Behçet'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 Behçet's disease were investigated in patients having GST-M1 and/or -T1 null polymorphisms.

METHODS

Ninety-seven patients meeting International Study Group Criteria for Behçet's 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 Behçet and the control groups. Smoking patients with GSTM1 null-polymorphism have decreased risk of developing papulopustuler lesions (OR=0.227 [0.063-0.818], χ2=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]). GSTT1 null-polymorphism is associated with the presence of venous insufficiency (χ2=6.273, p=0.012, OR=2.740 [1.224-6.135]); smoking further increases the risk (χ2=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 [0.981-1.367], χ2=4.760, p=0.029). Male smoker Behçet patients even have more risk (OR=1.250 [0.971-1.610]).

CONCLUSIONS

Several manifestations of Behçet'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.