Background

An increase in left ventricular mass (LVM) is associated with mortality and cardiovascular morbidity in patients with end-stage renal disease.

Methods and Results

The Frequent Hemodialysis Network (FHN) Daily Trial randomized 245 patients to 12 months of 6 times per week daily in-center hemodialysis or conventional hemodialysis; the FHN Nocturnal Trial randomized 87 patients to 12 months of 6 times per week nocturnal hemodialysis or conventional hemodialysis. The main cardiac secondary outcome was change in LVM. In each trial, we examined whether several pre-defined baseline demographic or clinical factors, as well as change in volume removal, blood pressure or solute clearance influenced the effect of frequent hemodialysis on LVM. In the Daily Trial, frequent hemodialysis resulted in a significant reduction in LVM (13.1(95% CI 5.0 to 21.3) g, p=0.002), LVM index (6.9 (2.4 to 11.3) g/m2, p=0.003) and percent change in geometric mean of LVM (7.0 (1.0 to 12.6)%, p =0.02). Similar trends were noted in the Nocturnal Trial but did not reach statistical significance. In the Daily Trial, a more pronounced effect of frequent hemodialysis on LVM was evident among patients with left ventricular hypertrophy at baseline. Changes in LVM were associated with changes in blood pressure (conventional hemodialysis: R=0.28, P=0.01, daily hemodialysis: R=0.54, P<0.001) and were not significantly associated with changes in other parameters.

Conclusions

Frequent in-center hemodialysis reduces LVM. The benefit of frequent hemodialysis on LVM may be mediated by salutary effects on blood pressure.

Prior small studies have shown multiple benefits of frequent nocturnal hemodialysis compared to conventional three times per week treatments. To study this further, we randomized 87 patients to three times per week conventional hemodialysis or to nocturnal hemodialysis six times per week, all with single-use high-flux dialyzers. The 45 patients in the frequent nocturnal arm had a 1.82-fold higher mean weekly stdKt/Vurea, a 1.74-fold higher average number of treatments per week, and a 2.45-fold higher average weekly treatment time than the 42 patients in the conventional arm. We did not find a significant effect of nocturnal hemodialysis for either of the two coprimary outcomes (death or left ventricular mass (measured by MRI) with a hazard ratio of 0.68, or of death or RAND Physical Health Composite with a hazard ratio of 0.91). Possible explanations for the left ventricular mass result include limited sample size and patient characteristics. Secondary outcomes included cognitive performance, self-reported depression, laboratory markers of nutrition, mineral metabolism and anemia, blood pressure and rates of hospitalization, and vascular access interventions. Patients in the nocturnal arm had improved control of hyperphosphatemia and hypertension, but no significant benefit among the other main secondary outcomes. There was a trend for increased vascular access events in the nocturnal arm. Thus, we were unable to demonstrate a definitive benefit of more frequent nocturnal hemodialysis for either coprimary outcome.

We investigated the effects of frequency of hemodialysis on nutritional status by analyzing the data in the Frequent Hemodialysis Network Trial. We compared changes in albumin, body weight and composition among 245 patients randomized to 6- or 3-times per week in-center hemodialysis (Daily Trial) and 87 patients randomized to 6-times per week nocturnal or 3-times per week conventional hemodialysis, performed largely at home (Nocturnal Trial). In the Daily Trial, there were no significant differences between groups in changes in serum albumin or the equilibrated protein catabolic rate by 12 months. There was a significant relative decrease in pre-dialysis body weight of 1.5 ± 0.2 kg in the 6 times per week group at one month, but this significantly rebounded by 1.3 ± 0.5 kg over the remaining 11 months. Extracellular water decreased in the 6 times per week compared to the 3 per week hemodialysis group. There were no significant between-group differences in phase angle, intracellular water or body cell mass. In the Nocturnal Trial, there were no significant between-group differences in any study parameter. Any gain in “dry” body weight corresponded to increased adiposity rather than muscle mass but was not statistically significant. Thus, frequent in-center hemodialysis reduced extracellular water but did not increase serum albumin or body cell mass while frequent nocturnal hemodialysis yielded no net effect on parameters of nutritional status or body composition.

Background

Poor sleep quality is a common, persistent, and important problem to patients with end-stage renal disease (ESRD). This report examines whether sleep quality is associated with dialysis treatment factors and other modifiable clinical factors in a large group of hemodialysis (HD) patients.

Methods

Cross-sectional analyses were conducted on baseline data collected from participants in the Frequent Hemodialysis Network trials. Sleep quality was measured using the Medical Outcomes Study Sleep Problems Index II (SPI II), a 9-item measure of sleep quality with higher scores reflecting poorer sleep quality.

Results

The participants had an age of 51.2 ± 13.6 years, 61% were male, 38% were black, and 42% had diabetes. Higher pre-dialysis serum phosphorus (per 0.5 mg/ml) (OR 0.91; 95% CI 0.85, 0.96) and depression (OR 0.16; 95% CI 0.10, 0.25) were independently associated with decrements in sleep quality. There was also a difference in time to recovery from dialysis for the fourth versus the first SPI II quartile (5.1 h; p < 0.0001).

Conclusion

These findings underscore the link between sleep and daytime function and suggest that improving sleep may provide an opportunity to improve outcomes in ESRD. Whether sleep problems may be improved by reduction of serum phosphorus or treatment of depression in the HD population merits further investigation.

Background

The annual mortality rate for maintenance hemodialysis patients in the United States remains unacceptably high at 15–20%. In 2004, we initiated the Frequent Hemodialysis Network (FHN) clinical trials. This report presents baseline characteristics of FHN trial participants and compares them to hemodialysis patients tracked in USRDS data.

Study design

Two separate randomized clinical trials

Settings and participants

FHN includes 332 patients with chronic kidney disease requiring chronic dialysis therapy enrolled in two separate randomized clinical trials. The FHN Daily Trial (245 randomized subjects) was designed to compare outcomes of six times per week in-center daily hemodialysis (1.5 to 2.75 hours/session) with conventional three times per week in-center hemodialysis. The FHN Nocturnal Trial (87 randomized subjects) was designed to compare outcomes of six times per week nocturnal (6 to 8 hours/session) with conventional three times per week hemodialysis. USRDS data includes 338109 incident and prevalent chronic hemodialysis patients from the calendar year 2007.

Results

Subjects in both trials were, on average, younger than the average hemodialysis patient in the United States (50.4 years; p<0.001 for Daily and 52.8 years; p<0.001 for Nocturnal). Compared to USRDS data, whites were underrepresented in the Daily Trial (36% versus 55%, p<0.001) while Hispanics were underrepresented in the Nocturnal Trial and overrepresented in the Daily Trial (0% versus 28%; p<0.001). In addition, there were more fistulas and fewer catheters in the Daily Trial (61% and 20% respectively, p<0.001 for both) and fewer grafts and more catheters in the Nocturnal Trial (10% and 44% respectively, p<0.005 for both).

Limitations

Clinical trial exclusion criteria and patient willingness to participate limit comparisons with the USRDS.

Conclusions

FHN participants are younger and the racial composition for each study was different than the racial composition of the aggregate US dialysis population. Catheters for vascular access were more common in FHN Nocturnal participants.

Background

Self-reported physical health and functioning and direct measures of physical performance are decreased in hemodialysis patients and are associated with mortality and hospitalization.

Study Design

We determined baseline cross-sectional associations of physical performance, health, and functioning with demographics, clinical characteristics, nutritional indexes, laboratory benchmarks, and measures of body composition in participants in the Frequent Hemodialysis Network (FHN) trial.

Setting & Participants

375 persons enrolled in the FHN with data for physical performance, health, and functioning.

Predictors

Explanatory variables were categorized into fixed factors of age, race, comorbid conditions (diabetes mellitus, heart failure, and peripheral arterial disease) and potentially modifiable factors of dialysis dose, phosphorus level, hemoglobin level, equilibrated normalized protein catabolic rate (enPCR), body composition, body mass index, phase angle, and ratio of intracellular water volume to body weight (calculated from bioelectrical impedance).

Outcomes

Scores on tests of physical performance, health, and functioning.

Measurements

Physical performance measured using the Short Physical Performance Battery, self-reported physical health and functioning using the 36-Item Short Form Health Survey (SF-36). Body composition (body mass index and bioimpedance analysis) and laboratory data were obtained from affiliated dialysis providers.

Results

Relative to population norms, scores for all 3 physicality metrics were low. Poorer scores on all 3 metrics were associated with diabetes mellitus and peripheral arterial disease. Poorer scores on the SF-36 Physical Functioning subscale and Short Physical Performance Battery also were associated with age, lower ratio of intracellular water volume to body weight, and lower enPCR. Black race was associated with poorer scores on the Short Physical Performance Battery.

Limitations

This was a cross-sectional study of individuals agreeing to participate in the FHN study and may not be generalizable to the general dialysis population.

Conclusions

Hemodialysis patients show markedly impaired physical performance, health, and functioning relative to population norms. Although some factors associated with these impairments are not modifiable, others may change with improvement in nutritional status or body composition.

Objective

To assess whether use of folic acid vitamin supplements reduces cardiac and stroke mortality in hemodialysis patients. Further, we examined whether consumption of folic acid from vitamin supplements greater than 1000 μg compared to standard 1000 μg, and 1000 μg compared to either lower dose or no consumption were associated with reduced cardiac and stroke mortality risk.

Design

Secondary analysis of data from the Hemodialysis (HEMO) Study, a randomized clinical trial examining dialysis treatment regimens over three years follow-up. Participants: One thousand eight hundred and forty-six hemodialysis patients previously participating in the HEMO study.

Interventions

None

Main Outcome Measure

Cardiac and stroke mortality.

Results

From time-dependent Cox proportional hazard regression models, folic acid consumption from vitamin supplements, above or below the standard 1000 μg dose was not associated with decrease or increase in cardiac mortality (P = 0.53 above vs. standard dose and P = 0.46, below vs. standard dose). There was also no association between folic acid consumption and mortality from stroke (P = 0.27, above vs. standard dose and P = 0.64, below vs. standard dose).

Conclusion

Consumption of higher than the standard 1000 μg prescribed dose of folic acid was not beneficial in reducing cardiac or stroke mortality in hemodialysis patients. Similarly, consumption of lower than standard dose was not associated with an increase in either cardiac or stroke mortality.