Kidney stones and the risk for chronic kidney disease

Abstract

Background and objectives: Kidney stones lead to chronic kidney disease (CKD) in people with rare hereditary disorders (e.g., primary hyperoxaluria, cystinuria), but it is unknown whether kidney stones are an important risk factor for CKD in the general population.

Design, setting, participants, & measurements: Among Olmsted County, MN, residents, all stone formers (n = 4774) whose condition was diagnosed in 1986 through 2003 were matched 1:3 to control subjects (n = 12,975). Cox proportional hazards models adjusted for age, gender, and comorbidities (hypertension, diabetes, obesity, dyslipidemia, gout, alcohol abuse, tobacco use, coronary artery disease, heart failure, cerebral infarct, and peripheral vascular disease) were used to assess the risk for incident CKD defined as a clinical diagnosis (diagnostic codes), ESRD or death with CKD, sustained (>90 d) elevated serum creatinine (>1.3 mg/dl in men, >1.1 mg/dl in women), or sustained estimated GFR <60 ml/min per 1.73 m(2).

Results: During a mean of 8.6 yr of follow-up, stone formers were at increased risk for a clinical diagnosis of CKD, but an increased risk for ESRD or death with CKD was NS. Among patients with follow-up serum creatinine levels, stone formers were at increased risk for a sustained elevated serum creatinine and a sustained reduced GFR.

Conclusions: Kidney stones are a risk factor for CKD, and studies are warranted to assess screening and preventive measures for CKD in stone formers.

Figure 1.

Sampling framework among Olmsted County, MN, residents. The sample size in stone former and control cohorts varied depending on whether follow-up and censoring were by clinic visits in Olmsted County or by serum creatinine (SCr) tests at the Mayo Clinic.

Figure 2.

Risk for chronic kidney disease (CKD) among Olmsted County, MN, stone formers and control subjects. (A through D) Cumulative incidence for any CKD diagnostic code (518 stone formers and 189 control subjects at risk at 18 yr, A); ESRD by dialysis or kidney transplant or death with CKD (577 stone formers and 229 control subjects at risk at 18 yr, B); and a sustained elevated SCr level with censoring by last clinic visit in Olmsted County (610 stone formers and 236 control subjects at risk at 18 yr, C) or with censoring by last SCr level at the Mayo Clinic (226 stone formers and 102 control subjects at risk at 18 yr, D).