Loop Diuretics in Chronic Kidney Disease

In CKD, impairment of renal function causes fluid and sodium retention and consequently expansion of extracellular volume, which corresponds to about 5% of body weight in absence of peripheral edema. In particular, sodium retention increases exponentially as glomerular filtration rate declines and is of primary importance in the pathogenesis of hypertension. Therefore, reduction of salt intake in renal patients allows a better blood pressure control. Despite the evidence collected on the beneficial effects of salt restriction in CKD, compliance with dietary prescription is generally poor in patients followed up in the real world of clinical practice. In the presence of poor adherence to salt restriction, diuretics agents become the cornerstone of treatment of hypertension secondary to CKD. Disappointingly, nephrologists are reluctant to "adequately" use loop diuretics in their hypertensive CKD patients, probably because of the fear of side effects and of the amazing absence in medical literature of studies of middle-long term on diuretic efficacy. Therefore, the primary aim of this study is to evaluate efficacy and safety of loop diuretics on blood pressure control in patients affected by CKD.

Inclusion criteria

• Chronic renal insufficiency in stage CKD 3 and 4 (GFR 60-15 ml/min/m2) estimated by Cockcroft-Gault formula corrected for body surface
• Systolic blood pressure >140 mmHg in treatment with at least 1 class of antihypertensive drugs
• Patients not in treatment from at least one month with loop diuretics

Exclusion criteria

• Loop diuretics treatment
• Variation of serum creatinine >30% in the last 3 months
• Steroid therapy and/or cytotoxic agents
• Edema syndromes (Nephrotic syndrome, cirrhosis, heart failure NYHA class 3 or 4)
• Neoplasia