Interdialytic Weight Gain May Increase Cardiovascular Risks
A 4% or greater increase in dry weight is associated with a 2-fold increased risk.
Shin-Wook Kang, MD, PhD, of Yonsei University College of Medicine in Seoul, Korea, and colleagues studied a prospective cohort of 1,013 incident HD patients. During a mean follow-up of 18.7 months, 104 patients (10.3%) experienced the primary outcome of major adverse cardiac and cerebrovascular events (MACCE).
In multivariate analysis, compared with patients with an IDWG of 1.0%-1.9% (reference), those with an IDWG of 4.0% or higher had a significant 93% increased risk of MACCE, Dr. Kang's group reported online ahead of print in the American Journal of Nephrology.
After adjusting for residual renal function and 24-hour urine volume, an IDWG of 4.0% or higher was associated with a significant 2.0 times increased risk of MACCE. The researchers also found a correlation between IDWG and predialysis systolic blood pressure.
“These findings suggest that prevention of excessive IDWG may be beneficial to cardiovascular outcomes even in incident HD patients, partly via protecting the heart from the deleterious effect of hypertension,” the authors wrote.
Speculating how IDWG might affect cardiovascular morbidity and mortality, the investigators explained that most HD patients undergo dialysis on a 3 times per week schedule. Such intermittent ultrafiltration can lead to fluctuations in extracellular fluid volume, which may promote cardiac remodeling and result in left ventricular hypertrophy and cardiac fibrosis.