Analysis of covariance was used to calculate geometric means of CdU adjusted for
age, sex, smoking status, log urine creatinine, and interaction terms: age-smoking status and sex-smoking
status. At selected ages, adjusted RR for exceeding each risk-associated CdU was highestfor current smokers
(3–13 times), followed by former smokers (2–3 times), compared to non-smokers. Adjusted RR for
smokers increased with age and was higher in females than males. Adjusted geometric means of CdUs
increased with age, were higher in females than in males regardless of smoking status, and were higher
in current smokers than former smokers, who had higher levels than non-smokers at any age. Cigarette
smoking greatly increases RR of exceeding renal risk-associated CdU. Former smokers retain significant
risk of exceeding these levels compared to non-smokers. CdU increased with age, particularly in current
smokers.