Reducing Fluid Overload May Be Better Than Antihypertensive Drugs for Blood Pressure Control in ESRD
By Laurie Barclay, MD
Medscape Medical News
June 7, 2010 — Reducing fluid overload may be better than antihypertensive drugs for blood pressure control in patients with end-stage renal disease (ESRD), according to the results of a qualitative literature review reported online May 27 in the Clinical Journal of the American Society of Nephrology.
"Achieving and maintaining dry-weight appears to be an effective but forgotten strategy in controlling and maintaining normotension among hypertensive patients on hemodialysis," write Rajiv Agarwal, from the Indiana University School of Medicine in Indianapolis, and Matthew R. Weir, from the University of Maryland Medical Center in Baltimore.
The purpose of this review was to define dry-weight and to assess its usefulness in achieving blood pressure control. With time, the concept of dry-weight has evolved, and its definition has changed accordingly. Dry-weight may be defined as the lowest tolerated postdialysis weight achieved through a gradual change in postdialysis weight with only minimal signs or symptoms of hypovolemia or hypervolemia.
Latent increase in dry-weight is not reliably identified on clinical examination. However, several technologies that may be useful in the future to measure dry-weight include relative plasma volume monitoring and body impedance analysis.
Sodium restriction is a modifiable risk factor that may help achieve better control of blood pressure, but lifestyle modifications needed to restrict dietary sodium are difficult to implement and even more difficult to sustain long term. A simpler, but less utilized and studied, strategy is to restrict dialysate sodium, which may reduce thirst and interdialytic weight gain while facilitating achievement of dry-weight. Benefits of achieving dry-weight may include better interdialytic blood pressure, lower pulse pressure, and fewer hospitalizations.
"Avoiding medication-directed control of BP [blood pressure] may enhance the opportunity to probe dry-weight, facilitate removal of volume, and limit the risk for pressure-volume overload, which may be a significant concern leading to myocardial remodeling in the hemodialysis patient," the review authors write. "Probing dry-weight among patients with ESRD has the potential to improve dismal cardiovascular outcomes."
The study authors have disclosed no relevant financial relationships.
Clin J Am Soc Nephrol. Published online May 27, 2010.