National Kidney Foundation practice guidelines for chronic kidney disease: evaluation,classification, and stratification

Chronic kidney disease is a worldwide public health problem with an increasing incidence and prevalence, poor outcomes, and high cost. Outcomes of chronic kidney disease include not only kidney failure but also complications of decreased kidney function and cardiovascular disease. Current evidence suggests that some of these adverse outcomes can be prevented or delayed by early detection and treatment. Unfortunately, chronic kidney disease is underdiagnosed and undertreated, in part as a result of lack of agreement on a definition and classification of its stages of progression. Recent clinical practice guidelines by the National Kidney Foundation 1) define chronic kidney disease and classify its stages, regardless of underlying cause, 2) evaluate laboratory measurements for the clinical assessment of kidney disease, 3) associate the level of kidney function with complications of chronic kidney disease, and 4) stratify the risk for loss of kidney function and development of cardiovascular disease. The guidelines were developed by using an approach based on the procedure outlined by the Agency for Healthcare Research and Quality. This paper presents the definition and five-stage classification system of chronic kidney disease and summarizes the major recommendations on early detection in adults. Recommendations include identifying persons at increased risk (those with diabetes, those with hypertension, those with a family history of chronic kidney disease, those older than 60 years of age, or those with U.S. racial or ethnic minority status), detecting kidney damage by measuring the albumin-creatinine ratio in untimed ("spot") urine specimens, and estimating the glomerular filtration rate from serum creatinine measurements by using prediction equations. Because of the high prevalence of early stages of chronic kidney disease in the general population (approximately 11% of adults), this information is particularly important for general internists and specialists.     

Chronic Kidney Disease Awareness Among Individuals with Clinical Markers of Kidney Dysfunction

Summary

Background and objectives

Awareness of chronic kidney disease (CKD) among providers and patients is low. Whether clinical cues prompt recognition of CKD is unknown. We examined whether markers of kidney disease that should trigger CKD recognition among providers are associated with higher individual CKD awareness.

Design, setting, participants, & measurements

CKD awareness was assessed in 1852 adults with an estimated GFR <60 ml/min per 1.73 m² using 1999 to 2008 National Health and Nutrition Examination Survey data. CKD awareness was a “yes” answer to “Have you ever been told you have weak or failing kidneys?” Participants were grouped by distribution of the following abnormal markers of CKD: hyperkalemia, acidosis, hyperphosphatemia, elevated blood urea nitrogen, anemia, albuminuria, and uncontrolled hypertension. Odds of CKD awareness associated with each abnormal marker and groupings of markers were estimated by multivariable logistic regression.

Results

Among individuals with kidney disease, only those with albuminuria had greater odds of CKD awareness (adjusted odds ratio, 4.0, P < 0.01) than those without. Odds of CKD awareness increased with each additional manifested clinical marker of CKD (adjusted odds ratio, 1.3, P = 0.05). Nonetheless, 90% of individuals with two to four markers of CKD and 84% of individuals with ≥5 markers of CKD were unaware of their disease.

Conclusions

Although individuals who manifest many markers of kidney dysfunction are more likely to be aware of their CKD, their CKD awareness remains low. A better understanding of mechanisms of awareness is required to facilitate earlier detection of CKD and implement therapy to minimize associated complications.     

Awareness of Hypertension and Proteinuria in Randomly Selected Patients in 11 Italian Cities. A 2005 Report of the National Kidney Foundation of Italy

Arterial hypertension and proteinuria are risk factors for chronic kidney disease. A mobile clinic was parked in a central plaza of 11 Italian cities to check blood pressure (BP), prescribe antihypertensive drugs, assess for proteinuria, and provide awareness about hypertension. Among 3757 patients, 56% were hypertensive, 37% were not diabetic nor proteinuric with BP ≥140/90 mm Hg, 17% were diabetic or proteinuric with BP ≥130/80 mm Hg, and 11% were on treatment with BP at target. Among 1204 treated patients, 400 (33%) had controlled BP. Among all 2114 hypertensive patients, only 1344 (64%) were aware of their hypertension. Awareness was greater among treated patients at target (99%). As many as 523 (14%) patients had proteinuria ≥30 mg/dL. The authors conclude that awareness of people walking in the street about their BP and proteinuria is insufficient. Mobile screening clinics may increase public awareness and detection of hypertension and proteinuria in the general community and detect patients at risk for chronic kidney disease.