Chapter 7: Overview of Benefits and Limitations of Home Hemodialysis

CARDIOVASCULAR DISEASE

Despite the advances in the management of end-stage kidney disease (ESKD) in recent years, cardiovascular disease remains the leading cause of death in ESKD patients and the principal discharge diagnosis accompanying one in four hospital admissions.¹ In addition to traditional cardiovascular risk factors, dialysis patients have additional risks, including ongoing exposure to volume overload, hyperphosphatemia, chronic inflammation, and uremic toxins. These risk factors can contribute to impaired structure and function of the heart and promote further progression of cardiovascular disease.²

[For more information, see Chapter 9.]

Left Ventricular Mass

An important predictor of cardiovascular morbidity and mortality in dialysis patients is left ventricular hypertrophy (LVH). In new dialysis patients, the prevalence of LVH is as high as 75%. Given that left ventricular mass (LVM) is an independent predictor of cardiovascular mortality, regression of LVH may reduce overall cardiovascular risk. Intensive hemodialysis (HD) has been shown to reduce LVM in multiple randomized trials. For example, the Frequent Hemodialysis Network (FHN) trial showed that short daily and nocturnal HD schedules were associated with significant reduction in the mean LVM from 142 g to 125 g (a 12% decrease), while decreasing only modestly with the conventional thrice-weekly HD schedule from 141 g to 138 g.

In a randomized controlled trial conducted at two Canadian institutions between August 2004 and December 2006, a total of 52 patients were recruited. The primary outcome was to compare the effects of frequent nocturnal hemodialysis (NHD) versus conventional hemodialysis (CHD) on change in LVM. The LVM decreased by a mean (SD) of 13.8 (23.0) g in the NHD group and increased by 1.5 (24.0) g in the CHD group (P=0.04).²

[For more information, see Chapter 9.]

Blood Pressure

Hypertension is very common in dialysis patients and may often be poorly controlled. Sodium and volume overload are the prominent mechanisms contributing to high blood pressure. Other mechanisms include arterial stiffness, activation of renin-angiotensin-aldosterone and sympathetic nervous systems, endothelial dysfunction, and sleep apnea. Multiple pharmacological and non-pharmacological interventions including increasing frequency of dialysis have been implemented in this population.³

In 1999, Woods et al. evaluated 72 patients that started daily HD between 1972 and 1996. Their predialysis systolic and diastolic blood pressures fell by 7 and 4 mm Hg respectively, after starting frequent HD (P=0.02). There was a statistically significant reduction in the number of antihypertensive medications prescribed during the 12 months after switching to daily HD. The percentage of patients receiving no antihypertensive medications increased from 54% to 61% at 6 months and 75% at 12 months after the switch to daily HD. The fraction of patients receiving more than one antihypertensive medication also decreased.⁴

More recently, in 2009, David et al. showed that more intensified nocturnal ...