Researchers at Heinrich-Heine University in Dusseldorf, Germany have linked smoking with the progression of diabetic nephropathy in people with type 1 diabetes undergoing hypertension therapy. The study was conducted over one year and included 34 smokers, 24 ex-smokers (anyone who had quit prior to the study), and 35 non-smokers, all of whom had both retinopathy and nephropathy (to insure that diabetes was the cause).
The progression of nephropathy was measured in all three groups as a whole, with non-smokers showing the least incidence of progression and smokers showing the highest. Progression of nephropathy occurred in 11% of the non-smokers, 33% of the ex-smokers, and 53% of the smokers. Reported in the February, 1994 issue of Diabetes Care.