Risk of hyperkalemia in nondiabetic patients with chronic kidney disease receiving antihypertensive therapy.

BACKGROUND: The incidence and factors associated with hyperkalemia in patients with chronic kidney disease (CKD) treated with angiotensin converting enzyme inhibitors (ACEIs) and other antihypertensive drugs was investigated using the African American Study of Kidney Disease and Hypertension (AASK) database. METHODS: A total of 1094 nondiabetic adults with hypertensive CKD (glomerular filtration rate [GFR], 20-65 mL/min/1.73 m(2)) were followed for 3.0 to 6.4 years in the AASK trial. Participants were randomly assigned to ACEI, beta-blocker (BB), or dihydropyridine calcium channel blocker (CCB). The outcome variables for this analysis were a serum potassium level higher than 5.5 mEq/L (to convert to millimoles per liter, multiply by 1.0), or a clinical center initiated hyperkalemia stop point. RESULTS: A total of 6497 potassium measurements were obtained, and 80 events in 51 subjects were identified (76 events driven by a central laboratory result and 4 driven by a clinical center-initiated hyperkalemia stop point). Compared with a GFR higher than 50 mL/min/1.73 m(2), after multivariable adjustment, the hazard ratio (HR) for hyperkalemia in patients with a GFR between 31 and 40 mL/min/1.73 m(2) and a GFR lower than 30 mL/min/1.73 m(2) was 3.61 (95% confidence interval [CI], 1.42-9.18 [P = .007]) and 6.81 (95% CI, 2.67-17.35 [P < .001]), respectively; there was no increased risk of hyperkalemia if GFR was 41 to 50 mL/min/1.73 m(2). Use of ACEIs was associated with more episodes of hyperkalemia compared with CCB use (HR, 7.00; 95% CI, 2.29-21.39 [P < .001]) and BB group (HR, 2.85; 95% CI, 1.50-5.42 [P = .001]). Diuretic use was associated with a 59% decreased risk of hyperkalemia. CONCLUSIONS: In nondiabetic patients with hypertensive CKD treated with ACEIs, the risk of hyperkalemia is small, particularly if baseline and follow-up GFR is higher than 40 mL/min/1.73 m(2). Including a diuretic in the regimen may markedly reduce risk of hyperkalemia.

Hypertension 2005: an evidence-based approach to diagnosis and treatment - an American perspective.

Midway into the first decade of the 21st century, evidence-based medicine has become the predominant methodology for the education and practice of medicine. In the ascent to this pre-eminent position, evidence-based medicine has challenged several methodologies through which medicine was taught and practiced throughout the 20th century, including the clinical anecdote, the concept that medicine is an art, the notion that the physician acts as the filter through which medical knowledge is individualized for the patient, and to some extent, the application of principles of pathophysiology to guide individual patient care. Indeed, it appears that in many cases, this mechanism-based approach to disease has been replaced by a broad strokes population-based approach based on outcomes research. However, as in the law, evidence is open to interpretation, varying opinion and nuance. Perhaps nowhere is this more evident than in the field of hypertension, which arguably can be credited with developing the field of evidence-based medicine with randomized clinical trials in the early 1960s and early adaptation and promotion of outcomes-based research, beginning with the first Joint National Committee report on prevention, detection, evaluation and treatment of high blood pressure in the 1970s. The purpose of this chapter is to review the evidence in the diagnosis and treatment of essential hypertension, focusing on the following areas. First, use of ambulatory and home blood pressure monitoring as diagnostic and prognostic tools; second, recent clinical trials in the treatment of essential hypertension that form the basis of evidence-based therapeutics; and third, presentation of the key features of the Joint National Committee (JNC) 7, which forms the current basis of treatment for essential hypertension.