Factors that showed significant associations with DPN in the univariate logistic regression included past (OR = 3.31; 95% CI = 1.75-6.27) and current smoking (OR = 3.31; 95% CI = 1.62-6.78), presence of chronic comorbidities (OR = 1.88; 95% CI = 1.02-3.44), early onset of diabetes (OR = 2.8; 95% CI = 1.36-5.76), longer duration of diabetes (OR = 3.17; 95% CI = 1.32-7.62), current insulin use (OR = 2.63; 95% CI = 1.48-4.67), presence of diabetes complications (OR = 2.89; 95% CI = 1.72-4.88), retinopathy (OR = 2.45; 95% CI = 1.46-4.12), and nephropathy (OR = 2.6; 95% CI = 1.43-4.72). This evidence concerns the gene INS and diabetes mellitus.