Smoking and cardiovascular outcomes in dialysis patients: the United States Renal Data System Wave 2 study.

Abstract

Smoking has received surprisingly little research attention in dialysis populations, a group at monumental cardiovascular risk. Medicare claims data were used to study associations between smoking and new-onset cardiovascular outcomes, and death in the prospective, inception Wave 2 cohort (N = 4024), assembled in 1996 and 1997. Of the participants, 56.4% were lifetime nonsmokers, 3.6% were smokers with unknown current status, 20.0% had quit for more than 1 year, 5.8% had quit less than 1 year ago, and 14.2% were current smokers. Subjects with cardiovascular disease at baseline were more likely to be former smokers, less likely never to have smoked and less likely to be current smokers (P < 0.001). Patients were followed until December 31, 1998. When adjustment was made for baseline age, demographic variables, mode of dialysis therapy, and comorbidity, smoking status was associated with new-onset congestive heart failure (adjusted hazards ratio 1.59 comparing current to nonsmokers, P = 0.004), new-onset peripheral vascular disease (adjusted hazards ratio 1.68, P < 0.001), and mortality (adjusted hazards ratio 1.37, P < 0.001). Former smokers, in contrast, had adjusted event risks similar to lifelong nonsmokers. Smoking is a major, modifiable, cardiovascular risk factor in patients starting dialysis therapy.