Smoking is related to albuminuria and abnormal renal function in nondiabetic persons.

BACKGROUND: Smoking induces albuminuria and accelerates progression to renal failure in persons with diabetes, but little is known about the relation between smoking and renal function in nondiabetic persons.
OBJECTIVE: To investigate whether smoking is related to albuminuria and abnormal renal function in nondiabetic persons.
DESIGN: Cross-sectional study.
SETTING: Groningen, The Netherlands. PARTICIPANTS: 7476 participants in the PREVEND (Prevention of REnal and Vascular ENd stage Disease) Study. MEASUREMENTS: Microalbuminuria and high normal albuminuria were defined as urinary albumin excretion of 30 to 300 mg/24 h and 15 to 30 mg/24 h, respectively. Elevated or decreased glomerular filtration rate (GFR) was defined as a creatinine clearance that exceeded or was less than two times the standard deviation of the mean value in nondiabetic, nonsmoking participants who had an albumin excretion of 0 to 15 mg/24 h, adjusted for age and sex.
RESULTS: Current smokers had a higher median albumin excretion than nonsmokers and were more likely to have microalbuminuria and high normal albuminuria with elevated or decreased GFR. After adjustment for several potential confounding factors, persons who smoked 20 or fewer cigarettes/d and persons who smoked more than 20 cigarettes/d, respectively, showed a dose-dependent association between smoking and high normal albuminuria (relative risk, 1.33 [95% CI, 1.10 to 1.61] and 1.98 [CI, 1.49 to 2.64]), microalbuminuria (relative risk, 1.92 [CI, 1.54 to 2.39] and 2.15 [CI, 1.52 to 3.03]), elevated GFR (relative risk, 1. 82 [CI, 1.31 to 2.53] and 1.84 [CI, 1.12 to 3.02]), and decreased GFR (relative risk, 1.53 [CI, 1.04 to 2.24] and 1.83 [CI, 1.05 to 3. 20]), respectively. Quitting smoking was associated only with microalbuminuria.
CONCLUSIONS: Smoking is associated with albuminuria and abnormal renal function. However, these associations are less pronounced or absent in former smokers.