The risk for mild kidney function decline associated with illicit drug use among hypertensive men.

BACKGROUND: Few studies have examined the deleterious effect of illicit drug use on kidney function.
METHODS: Six hundred forty-seven patients enrolled in the Hypertension Clinic of the Veterans Administration Medical Center of New Orleans, LA, were interviewed regarding illicit drug use and followed up for a median of 7 years to determine the incidence of mild kidney function decline (increase in serum creatinine level > or = 0.6 mg/dL [> or =53.0 micromol/L]) between 1977 and 1999.
RESULTS: Twenty-three percent of study participants reported the use of illicit drugs: 22.7%, marijuana; 6.7%, cocaine or crack; 9.3%, amphetamines; 3.1%, psychedelics; and 4.3%, heroin. After adjustment for age, race, education, income, smoking, alcohol consumption, systolic blood pressure, use of antihypertensive medications, body mass index, and history of diabetes and dyslipidemia, relative risk for mild kidney function decline associated with any drug use was 2.3 (95% confidence interval, 1.0 to 5.1). After similar adjustments, risks for mild kidney function decline were 3.0 (95% confidence interval, 1.1 to 8.0) and 3.9 (95% confidence interval, 1.1 to 14.4) times greater among persons who had used cocaine and psychedelics, respectively. Use of marijuana, amphetamines, heroin, and other drugs was associated with elevated, but not statistically significant, risks for mild kidney function decline.
CONCLUSION: Our study documented a significant, positive, and independent association between illicit drug use and risk for mild kidney function decline. This finding indicates that interventions aimed at helping patients discontinue illicit drug use and maintain a drug-free lifestyle may have an important role in delaying and/or preventing the onset of kidney disease in hypertensive men.