Among people who had exposure to oral cancer-related environmental risk factors such as areca , alcohol , and tobacco consumption , the adjusted odd ratios and 95 % confidence intervals were increased to a 2.02-fold ( 95 % CI = 1.01-4 .04 ; p = 0.04 ) , 4.04 ( 95 % CI = 1.65-9 .87 ; p = 0.002 ) and a 1.66-fold ( 95 % CI = 1.00-2 .84 ; p = 0.05 ) risk of developing oral cancer .