Tobacco, hypertension, and vascular disease: Risk factors for renal functional decline in an older population

Background. A decline in renal function with age has been noted in some but not all individuals. The purpose of this study was to identify risk factor s associated with a clinically significant increase in serum creatinine (of at least 0.3 mg/dL) in an older nondiabetic population. Methods. A retrospective case-control study was performed analyzing data ob tained from 4142 nondiabetic participants of the Cardiovascular Health Stud y Cohort, all at least 65 years of age, who had two measurements of serum c reatinine performed at least three years apart. Cases were identified as pa rticipants who developed an increase in serum creatinine of at least 0.3 mg /dL, with controls including participants who did not sustain such an incre ase. Results. There was an increase in the serum creatinine of at least 0.3 mg/d L in 2.8% of the population. in a multivariate "best-fit" model adjusted fo r gender, weight, black race, baseline serum creatinine, and age, the follo wing factors were associated with an increase in serum creatinine: number o f cigarettes smoked per day, systolic blood pressure, and maximum internal carotid artery intimal thickness. Conclusions. These data suggest that three very preventable or treatable co nditions-hypertension, smoking, and prevalent vascular disease, which are a ssociated with large and small vessel disease-are highly associated with cl inically important changes in renal function in an older population.