Associations of self-reported physical activity types and levels with quality of life, depression symptoms, and mortality in hemodialysis patients: the DOPPS.

BACKGROUND AND OBJECTIVES: Physical activity has been associated with better health status in diverse populations, but the association in patients on maintenance hemodialysis is less established. Patient-reported physical activities and associations with mortality, health-related quality of life, and depression symptoms in patients on maintenance hemodialysis in 12 countries were examined. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: In total, 5763 patients enrolled in phase 4 of the Dialysis Outcomes and Practice Patterns Study (2009-2011) were classified into five aerobic physical activity categories (never/rarely active to very active) and by muscle strength/flexibility activity using the Rapid Assessment of Physical Activity questionnaire. The Kidney Disease Quality of Life scale was used for health-related quality of life. The Center for Epidemiologic Studies Depression scale was used for depression symptoms. Linear regression was used for associations of physical activity with health-related quality of life and depression symptoms scores. Cox regression was used for association of physical activity with mortality. RESULTS: The median (interquartile range) of follow-up was 1.6 (0.9-2.5) years; 29% of patients were classified as never/rarely active, 20% of patients were classified as very active, and 20.5% of patients reported strength/flexibility activities. Percentages of very active patients were greater in clinics offering exercise programs. Aerobic activity, but not strength/flexibility activity, was associated positively with health-related quality of life and inversely with depression symptoms and mortality (adjusted hazard ratio of death for very active versus never/rarely active, 0.60; 95% confidence interval, 0.47 to 0.77). Similar associations with aerobic activity were observed in strata of age, sex, time on dialysis, and diabetes status. CONCLUSIONS: The findings are consistent with the health benefits of aerobic physical activity for patients on maintenance hemodialysis. Greater physical activity was observed in facilities providing exercise programs, suggesting a possible opportunity for improving patient outcomes.

Recovery time, quality of life, and mortality in hemodialysis patients: the Dialysis Outcomes and Practice Patterns Study (DOPPS).

BACKGROUND: There is limited information about the clinical and prognostic significance of patient-reported recovery time. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: 6,040 patients in the DOPPS (Dialysis Outcomes and Practice Patterns Study). PREDICTOR: Answer to question "How long does it take you to recover from a dialysis session?" categorized as follows: fewer than 2, 2-6, 7-12, or longer than 12 hours. OUTCOMES & MEASUREMENTS: Cross-sectional and longitudinal associations between recovery time and patient characteristics, hemodialysis treatment variables, health-related quality of life (HRQoL), and hospitalization and mortality. RESULTS: 32% reported recovery time shorter than 2 hours; 41%, 2-6 hours; 17%, 7-12 hours; and 10%, longer than 12 hours. Using proportional odds (ordinal) logistic regression, shorter recovery time was associated with male sex, full-time employment, and higher serum albumin level. Longer recovery time was associated with older age, dialysis vintage, body mass index, diabetes, and psychiatric disorder. Greater intradialytic weight loss, longer dialysis session length, and lower dialysate sodium concentration were associated with longer recovery time. In facilities that used uniform dialysate sodium concentrations for ≥90% of patients, the adjusted OR of longer recovery time, comparing dialysate sodium concentration<140 vs 140 mEq/L, was 1.72 (95% CI, 1.37-2.16). Recovery time was correlated positively with symptoms of kidney failure and kidney disease burden score and inversely with HRQoL mental and physical component summary scores. Using Cox regression, adjusting for potential confounders not influenced by recovery time, it was associated positively with first hospitalization and mortality (adjusted HRs for recovery time>12 vs 2-6 hours 1.22 [95% CI, 1.09-1.37] and 1.47 [95% CI, 1.19-1.83], respectively). LIMITATIONS: Answers are subjective and not supported by physiologic measurements. CONCLUSIONS: Recovery time can be used to identify patients with poorer HRQoL and higher risks of hospitalization and mortality. Interventions to reduce recovery time and possibly improve clinical outcomes, such as increasing dialysate sodium concentration, need to be tested in randomized trials.

Hospitalization risks related to vascular access type among incident US hemodialysis patients.

BACKGROUND: The excess morbidity and mortality related to catheter utilization at and immediately following dialysis initiation may simply be a proxy for poor prognosis. We examined hospitalization burden related to vascular access (VA) type among incident patients who received some predialysis care. METHODS: We identified a random sample of incident US Dialysis Outcomes and Practice Patterns Study hemodialysis patients (1996-2004) who reported predialysis nephrologist care. VA utilization was assessed at baseline and throughout the first 6 months on dialysis. Poisson regression was used to estimate the risk of all-cause and cause-specific hospitalizations during the first 6 months. RESULTS: Among 2635 incident patients, 60% were dialyzing with a catheter, 22% with a graft and 18% with a fistula at baseline. Compared to fistulae, baseline catheter use was associated with an increased risk of all-cause hospitalization [adjusted relative risk (RR) = 1.30, 95% confidence interval (CI): 1.09-1.54] and graft use was not (RR = 1.07, 95% CI: 0.89-1.28). Allowing for VA changes over time, the risk of catheter versus fistula use was more pronounced (RR = 1.72, 95% CI: 1.42-2.08) and increased slightly for graft use (RR = 1.15, 95% CI: 0.94-1.41). Baseline catheter use was most strongly related to infection-related (RR = 1.47, 95% CI: 0.92-2.36) and VA-related hospitalizations (RR = 1.49, 95% CI: 1.06-2.11). These effects were further strengthened when VA use was allowed to vary over time (RR = 2.31, 95% CI: 1.48-3.61 and RR = 3.10, 95% CI: 1.95-4.91, respectively). A similar pattern was noted for VA-related hospitalizations with graft use. Discussion. Among potentially healthier incident patients, hospitalization risk, particularly infection and VA-related, was highest for patients dialyzing with a catheter at initiation and throughout follow-up, providing further support to clinical practice recommendations to minimize catheter placement.

The associations of social support and other psychosocial factors with mortality and quality of life in the dialysis outcomes and practice patterns study.

BACKGROUND AND OBJECTIVES: This study aimed to investigate the influence of social support and other psychosocial factors on mortality, adherence to medical care recommendations, and physical quality of life among hemodialysis patients. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Data on 32,332 hemodialysis patients enrolled in the Dialysis Outcomes and Practice Patterns Study (1996 to 2008) in 12 countries were analyzed. Social support and other psychosocial factors related to ESRD and its treatment were measured by patient self-reports of health interference with social activities, isolation, feeling like a burden, and support from family and dialysis staff. Cox regression and logistic regression were used to examine associations of baseline social support and other psychosocial factors with all-cause mortality and with other measured outcomes at baseline, adjusting for potential confounders. RESULTS: Mortality was higher among patients reporting that their health interfered with social activities, were isolated, felt like a burden, and were dissatisfied with family support. Poorer family support and several psychosocial measures also were associated with lower adherence to the prescribed hemodialysis length and the recommended weight gain between sessions. Some international differences were observed. Poorer self-reported social support and other psychosocial factors were associated with poor physical quality of life. CONCLUSIONS: Poorer social support and other psychosocial factors are associated with higher mortality risk, lower adherence to medical care, and poorer physical quality of life in hemodialysis patients. More research is needed to assess whether interventions to improve social support and other psychosocial factors will lengthen survival and enhance quality of life.

Conversion of vascular access type among incident hemodialysis patients: description and association with mortality.

BACKGROUND: Limited data exist describing vascular access conversions during the first year on dialysis therapy or the effect of converting to and from a catheter on subsequent mortality risk. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: We studied a random sample of incident US hemodialysis patients (initiated long-term dialysis < 30 days before study entry) in the Dialysis Outcomes and Practice Patterns Study (DOPPS; 1996-2004). PREDICTORS: At dialysis therapy initiation, we assessed vascular access type in use (arteriovenous fistula [AVF], arteriovenous graft [AVG], or catheter) and other patient characteristics. We characterized changes in vascular access type (conversions) by using regularly collected functional status information. OUTCOME & MEASUREMENTS: We assessed time to all-cause mortality. We first described conversions, then used time-dependent Cox regression to estimate mortality hazard ratios (HRs) for conversions from a catheter to a permanent vascular access (versus no conversion) and conversions from a permanent vascular access to a catheter (versus no conversion). RESULTS: The study included 4,532 patients; 69.2% were dialyzing with a catheter; 17.6%, with an AVG; and 13.1%, with an AVF. In patients initiating therapy with an AVF or AVG, 22% experienced a conversion (failure), and median times to first failure were 62 and 84 days, respectively. In catheter patients, 59% converted to an AVF/AVG (predominantly AVG [57%]); median times to first conversion were 92 and 66 days, respectively. Conversion to a permanent access was associated with an adjusted mortality HR of 0.69 (95% confidence interval, 0.55 to 0.85). The effect was similar for conversion to an AVF or AVG, and these persisted across demographic groups and facilities with different conversion practices. Conversion from a permanent vascular access to a catheter was associated with an adjusted mortality HR of 1.81 (95% confidence interval, 1.22 to 2.68). LIMITATIONS: Potential for residual confounding because of unmeasured factors influencing decision to convert. CONCLUSION: Vascular access conversions are common in incident patients. Continued efforts to increase early nephrologist referral and permanent vascular access placement may help decrease mortality risk in incident dialysis patients.

Travel time to dialysis as a predictor of health-related quality of life, adherence, and mortality: the Dialysis Outcomes and Practice Patterns Study (DOPPS).

BACKGROUND: Longer travel time to the dialysis unit creates a substantial burden for many patients. This study evaluated the effect of self-reported 1-way travel time to hemodialysis on mortality, health-related quality of life (HR-QOL), adherence, withdrawal from dialysis therapy, hospitalization, and transplantation. STUDY DESIGN: Prospective observational cohort. SETTING & PARTICIPANTS: Patients enrolled in the Dialysis Outcomes and Practices Patterns Study who completed a patient questionnaire (n = 20,994). PREDICTOR: One-way travel time to hemodialysis treatment, categorized as 15 or less, 16 to 30, 31 to 60, and longer than 60 minutes. Covariates included demographics, comorbid conditions, serum albumin level, time on dialysis therapy, and country. OUTCOME & MEASUREMENT: HR-QOL was examined by using a linear mixed model. Cox proportional hazards regression was used to examine associations with mortality, withdrawal from dialysis therapy, hospitalization, and transplantation. RESULTS: Longer travel time was associated with greater adjusted relative risk (RR) of death (P = 0.05 for overall trend). Adjusted HR-QOL subscales were significantly lower for those with longer travel times compared with those traveling 15 minutes or less. There were no associations of travel time with withdrawal from dialysis therapy (P = 0.6), hospitalization (P = 0.4), or transplantation (P = 0.7). LIMITATIONS: The questionnaire nonresponse rate was substantial, and nonresponders were older, with more comorbid conditions. Travel time was assessed by using a single nonvalidated question. CONCLUSIONS: Longer travel time is associated significantly with greater mortality risk and decreased HR-QOL. Exploring opportunities to decrease travel time should be incorporated into the dialysis clinical routine.

Lack of appetite in haemodialysis patients--associations with patient characteristics, indicators of nutritional status and outcomes in the international DOPPS.

BACKGROUND: Identification of haemodialysis patients with problems related to lack of appetite should help prevent adverse outcomes. We studied whether a single question about being bothered by lack of appetite within the prior 4 weeks is related to nutritional status, inflammation and risks of death and hospitalization. Additionally, we assessed associations of lack of appetite with depression, dialysis dose and length of haemodialysis. METHODS: This study is an analysis of baseline and longitudinal data from 14 406 patients enrolled in the Dialysis Outcomes and Practice Pattern Study. Cox regression was used to assess whether the degree (not, somewhat, moderately, very much, extremely) that patients were bothered by lack of appetite is an independent predictor of death and hospitalization. Logistic regression was used to identify baseline characteristics associated with being bothered by lack of appetite. RESULTS: The risk of death was more than 2-fold higher [relative risk (RR) = 2.23; 95% confidence interval (CI) = 1.90-2.62] and the risk of hospitalization 33% higher (RR = 1.33; 95% CI = 1.19-1.48) among patients extremely bothered, compared with not bothered, by lack of appetite. These associations followed a dose-response fashion and remained statistically significant after adjustments for 14 comorbidities. Depression, shorter haemodialysis session, hypoalbuminaemia, lower concentration of serum creatinine and normalized protein catabolic rate, lower body mass index and higher leucocyte and neutrophil counts were independently associated with higher odds of being bothered by lack of appetite. CONCLUSIONS: The data suggest that a single question about lack of appetite helps identify haemodialysis patients with poorer nutritional status, inflammation, depression and higher risks of hospitalization and death. The study calls attention to a possible beneficial effect of longer haemodialysis on appetite.

Factors associated with health-related quality of life among hemodialysis patients in the DOPPS.

OBJECTIVE: To identify modifiable factors associated with health-related quality of life (HRQOL) among chronic hemodialysis patients. METHODS: Analysis of baseline data of 9,526 hemodialysis patients from seven countries enrolled in phase I of the Dialysis Outcomes and Practice Patterns Study (DOPPS). Using the Kidney Disease Quality of Life Short Form (KDQOL-SF(TM)), we determined scores for 8 generic scale summaries derived from these scales, i.e., the physical component summary [PCS] and mental component summary [MCS], and 11 kidney disease- targeted scales. Regression models were used to adjust for differences in comorbidities and sociodemographic and treatment factors. The Benjamini-Hochberg procedure was used to correct P-values for multiple comparisons. RESULTS: Unemployment and psychiatric disease were independently and significantly associated with lower scores for all generic and several kidney disease-targeted HRQOL measures. Several other comorbidities, lower educational level, lower income, and hypoalbuminemia were also independently and significantly associated with lower scores of PCS and/or MCS and several generic and kidney disease-targeted scales. Hemodialysis by catheter was associated with significantly lower PCS scores, partially explained by the correlation with covariates. CONCLUSION: Associations of poorer HRQOL with preventable or controllable factors support a greater focus on psychosocial and medical interventions to improve the well-being of hemodialysis patients.

Sexual dysfunction in dialysis patients treated with antihypertensive or antidepressive medications: results from the DOPPS.

BACKGROUND: The relationship between medication prescription and sexual dysfunction (SD) in dialysis patients is unclear. METHODS: We studied antihypertensive and antidepressive agents prescribed for 7346 patients in the Dialysis Outcomes and Practice Patterns Study phase 1 (DOPPS I) and 8891 patients in DOPPS II. At baseline, DOPPS I patients completed a quality of life survey, including four questions about sexual functioning, from which we created a composite SD scale. DOPPS II patients were asked only one question about SD. We examined predictors of SD with logistic regression, using numerous patient characteristics, comorbid conditions and additional variables. RESULTS: Reported SD ranged from 66.4% (France) to 84.5% (Spain). The mean composite SD score ranged from 6.4 (Spain) to 7.9 (Germany) (on a 3-15 scale). Peripheral alpha-blockers increased odds of DOPPS I patients having their sex life bothered by end-stage renal disease (ESRD) (OR=1.18), and there were elevated odds of arousal problems with central antagonists, loop diuretics and peripheral alpha-blockers (OR=1.19, 1.24 and 1.29, respectively). Selective serotonin reuptake inhibitors (SSRIs) and benzodiazepines increased odds of problems with enjoyment (OR=1.59 and 1.26, respectively) and arousal (OR=1.70 and 1.24, respectively), and having sex life bothered by ESRD (DOPPS I: OR=1.36 and 1.24; DOPPS II: 1.30 and 1.31, respectively). Vasodilators reduced the odds of sexual enjoyment problems (OR=0.75). Composite SD scores worsened with peripheral alpha-blockers (+0.41), tricyclics (+0.78), SSRIs (+0.80) and benzodiazepines (+0.50), but not with vasodilators (-0.57). CONCLUSIONS: Awareness of associations between SD and prescribed medications may offer opportunities for intervention.

Correlates and outcomes of dementia among dialysis patients: the Dialysis Outcomes and Practice Patterns Study.

BACKGROUND: Recent studies suggest a high prevalence of cognitive impairment and dementia in persons with end-stage renal disease (ESRD), yet risk factors for dementia and its prognostic significance in persons with ESRD remain unclear. The goals of this study were to determine the prevalence, correlates and dialysis-related outcomes of dementia in an international sample of haemodialysis patients. METHODS: We analysed data collected from a cohort of 16 694 patients in the Dialysis Outcomes and Practice Patterns Study. Dementia was defined as a diagnosis of dementia documented in the medical record. We used logistic regression to determine the baseline correlates of dementia and Cox proportional hazards models to determine the relative risk (RR) of death and dialysis withdrawal for patients with dementia, while adjusting for a number of confounding factors. RESULTS: Overall, 4% of the cohort had a recorded diagnosis of dementia. In the cross-sectional analyses, risk factors for dementia in the general population including age, black race, low educational attainment, cerebrovascular disease and diabetes, as well as modifiable uraemia-related factors, including markers of malnutrition and anaemia, were independently associated with dementia. After adjustment for a number of confounding factors, dementia was associated with an increased risk of death [RR 1.48, 95% confidence interval (CI) 1.32-1.66] and dialysis withdrawal (RR 2.01, 95% CI 1.57-2.57). CONCLUSIONS: Dementia is associated with adverse outcomes among ESRD patients. Dialysis providers should consider instituting routine screening for cognitive impairment among elderly patients in order to identify those at risk for associated adverse outcomes.

Self-management in patients with end stage renal disease: exploring domains and dimensions.

The management and appropriate treatment of chronic disease are ongoing challenges in health care. As the population ages, the prevalence of chronic disease can be expected to increase. Since by definition there is no cure for chronic disease, controlling, minimizing, or managing its negative effects becomes a primary goal. In the self-management perspective, it is neither clinicians nor health care systems who must accomplish the bulk of chronic disease management but rather the patients themselves. Moreover, self-management has been shown to be associated with improved outcomes. Self-management is comprised of two domains: self-management of health care and self management of everyday life. Self-management of health care includes self-care activity, partnership in care, communication, self-care self-efficacy, and adherence. Self-management of everyday life entails achieving/maintaining "normality" in everyday roles and functioning. End stage renal disease (ESRD) is a chronic disease for which self-management is particularly relevant. Understanding the components of self-management may help patients and clinicians to embrace this approach, to enter the mutual relationship it requires, and to maximize positive outcomes for patients with ESRD.

Nurses' impact on the choice and longevity of vascular access.

A preponderance of data highlights significant improvements in outcomes when patients dialyze with arteriovenous fistulae compared with either catheters or grafts. "Fistula First" is a nationwide, evidence-based, quality improvement effort that is striving to improve vascular access outcomes by increasing the percentage of patients who dialyze with arteriovenous fistulae. Nephrology nurses will have a profound effect on achieving the goals outlined by Fistula First, including both the choice and longevity of vascular accesses.

Screening for depression in hemodialysis patients: associations with diagnosis, treatment, and outcomes in the DOPPS.

BACKGROUND: Depressive symptoms and depression are the most frequent psychologic problems reported by hemodialysis patients. We assessed the prevalence of depressive symptoms and physician-diagnosed depression, their variations by country, and associations with treatment by antidepressants among hemodialysis patients. We also assessed whether depressive symptoms were independently associated with mortality, hospitalization, and dialysis withdrawal. METHODS: The sample was represented by 9382 hemodialysis patients randomly selected from dialysis centers of 12 countries enrolled in the Dialysis Outcomes and Practice Patterns Study (DOPPS II). Depressive symptoms were assessed by the short version of the Center for Epidemiological Studies Depression Screening Index (CES-D), using > or =10 CES-D score as the cut-off value. RESULTS: Overall prevalence of physician-diagnosed depression was 13.9%, and percentage of CES-D score > or =10 43.0%. While the smallest prevalence of physician-diagnosed depression was observed in Japan (2.0%) and France (10.6%), the percentage of CES-D score > or =10 in these counties was similar to the whole sample. Patients on antidepressants also varied by country, 34.9% and 17.3% among those with physician-diagnosed depression and CES-D scores > or =10, respectively. In Cox models adjusted for several comorbidities, CES-D scores > or =10 were associated with significantly higher relative risks (RR) of death (RR = 1.42; 95% CI = 1.29 to 1.57), hospitalization (RR = 1.12; 95% CI = 1.03 to 1.22), and dialysis withdrawal (RR = 1.55; 95% CI = 1.29 to 1.85). CONCLUSION: The data suggest that depression is underdiagnosed and undertreated among hemodialysis patients. CES-D can help identify hemodialysis patients who are at higher risk of death and hospitalization. Interventions should target these patients with the goal to improve survival and reduce hospitalizations.

Health-related quality of life in the Dialysis Outcomes and Practice Patterns Study (DOPPS).

BACKGROUND: Health-related quality of life (HRQOL), a validated system of measuring patients' physical, mental, and social well-being, can be of particular use in populations with chronic conditions, such as end-stage renal disease (ESRD). METHODS: The Dialysis Outcomes and Practice Patterns Study (DOPPS) has used the Kidney Disease Quality of Life Short Form (KDQOL-SF) to measure ESRD patients' self-assessment of functioning and well-being, as measured by 3 component scores: physical component summary (PCS, 4 subscales), mental component summary (4 subscales), and kidney disease component summary (11 subscales). Several DOPPS studies examined HRQOL's associations with mortality and hospitalization by country, ethnicity (United States only), and in comparison with serum albumin levels; international variations in HRQOL of ESRD patients were also evaluated. RESULTS: Lower scores for all 3 summary scores were strongly associated with higher risk of death and hospitalization; these measures, especially PCS, may better identify patients at risk for death and hospitalization than serum albumin level. Japanese patients reported a greater burden of kidney disease but higher physical functioning than patients in Europe or the United States; many other significant regional differences in HRQOL were found. In the United States, all summary scores were significantly associated with mortality risk, regardless of ethnicity. Compared with whites, blacks had higher scores for all 3 summary scores, Asians and Hispanics had higher PCS scores, and Native Americans had lower mental component summary scores. CONCLUSION: Among ESRD patients, HRQOL displays an important predictive power for adverse events. Identifying effective interventions to improve the HRQOL of patients with ESRD should be viewed as a valued health care goal.

Reliability and validity of a risk assessment tool for patients with kidney failure.

Reliable and valid tools are needed to assist nurses to prospectively identify high-risk patients with kidney failure. Early identification of high-risk patients permits targeting of nursing interventions and resources to improve quality and cost outcomes. A 16-item risk assessment tool Risk for Outcomes Adverse to Dialysis (ROAD), was developed based on a comprehensive review of the literature on risk factors associated with adverse outcomes with kidney failure Reliability and validity of the ROAD was tested on a random sample of 253 participants in the Anemia Management Demonstration Project. High risk scores on the ROAD were significantly associated with hospitalization 1 to 6 months following risk assessment and inversely correlated with physical and mental components of quality of life. The results indicate that the ROAD provides a useful tool to identify patients on hemodialysis at risk of poor outcomes.

Health-related quality of life among dialysis patients on three continents: the Dialysis Outcomes and Practice Patterns Study.

BACKGROUND: Assessing health-related quality of life (HRQOL) can provide information on the types and degrees of burdens that afflict patients with chronic medical conditions, including end-stage renal disease (ESRD). Several studies have shown important international differences among ESRD patients treated with hemodialysis, but no studies have compared these patients' HRQOL. Our goal was to document international differences in HRQOL among dialysis patients and to identify possible explanations of those differences. METHODS: We examined data from the Dialysis Outcomes and Practice Patterns Study (DOPPS), a prospective, observational, international study of hemodialysis patients. We performed a cross-sectional analysis of DOPPS data from the United States, five countries in Europe (France, Germany, Italy, Spain, and the United Kingdom), and Japan. Linear mixed models were used to analyze differences in HRQOL, using the KDQOL-SFTM. Norm-based scores were used to minimize cultural response bias. Linear regression analysis was used to adjust for confounding factors. Other variables included demographic variables, comorbidities, primary cause of ESRD, complications of ESRD and treatment, and socioeconomic status. RESULTS: In all generic HRQOL subscales, patients on all three continents had much lower scores than their respective population norm values. Patients in the United States had the highest scores on the mental health subscale and the highest mental component summary scores. Japanese patients reported better physical functioning than did patients in the United States or Europe, but they also reported the greatest burden of kidney disease. Overall, these differences remained even after adjusting for possible confounders. CONCLUSION: On all three continents, ESRD and hemodialysis profoundly affect HRQOL. In the United States, the effects on mental health are smaller than in other countries. Japanese hemodialysis patients perceived that their kidney disease imposes a greater burden, but their physical functioning was significantly higher. Different distributions of socioeconomic factors and major comorbid conditions could explain little of this difference in physical functioning. Other possible factors, such as quality of dialysis and related health care, deserve careful study.

Health-related quality of life as a predictor of mortality and hospitalization: the Dialysis Outcomes and Practice Patterns Study (DOPPS).

BACKGROUND: We investigated whether indicators of health-related quality of life (HRQOL) may predict the risk of death and hospitalization among hemodialysis patients treated in seven countries, taking into account serum albumin concentration and several other risk factors for death and hospitalization. We also compared HRQOL measures with serum albumin regarding their power to predict outcomes. METHODS: We analyzed data from the Dialysis Outcomes and Practice Patterns Study (DOPPS), an international, prospective, observational study of randomly selected hemodialysis patients in the United States (148 facilities), five European countries (101 facilities), and Japan (65 facilities). The total sample size was composed of 17,236 patients. Using the Kidney Disease Quality of Life Short Form (KDQOL-SFTM), we determined scores for three components of HRQOL: (1) physical component summary (PCS), (2) mental component summary (MCS), and (3) kidney disease component summary (KDCS). Complete responses on HRQOL measures were obtained from 10,030 patients. Cox models were used to assess associations between HRQOL and the risk of death and hospitalization, adjusted for multiple sociodemographic variables, comorbidities, and laboratory factors. RESULTS: For patients in the lowest quintile of PCS, the adjusted risk (RR) of death was 93% higher (RR = 1.93, P < 0.001) and the risk of hospitalization was 56% higher (RR = 1.56, P < 0.001) than it was for patients in the highest quintile level. The adjusted relative risk values of mortality per 10-point lower HRQOL score were 1.13 for MCS, 1.25 for PCS, and 1.11 for KDCS. The corresponding adjusted values for RR for first hospitalization were 1.06 for MCS, 1.15 for PCS, and 1.07 for KDCS. Each RR differed significantly from 1 (P < 0.001). For 1 g/dL lower serum albumin concentration, the RR of death adjusted for PCS, MCS, and KDCS and the other covariates was 1.17 (P < 0.01). Albumin was not significantly associated with hospitalization (RR = 1.03, P> 0.5). CONCLUSION: Lower scores for the three major components of HRQOL were strongly associated with higher risk of death and hospitalization in hemodialysis patients, independent of a series of demographic and comorbid factors. A 10-point lower PCS score was associated with higher elevation in the adjusted mortality risk, as was a 1 g/dL lower serum albumin level. More research is needed to assess whether interventions to improve quality of life lower these risks among hemodialysis patients.

Health-related quality of life and associated outcomes among hemodialysis patients of different ethnicities in the United States: the Dialysis Outcomes and Practice Patterns Study (DOPPS).

BACKGROUND: In the United States, an association between mortality risk and ethnicity has been observed among hemodialysis patients. This study was developed to assess whether health-related quality of life (HRQOL) scores also vary among patients of different ethnic backgrounds. Associations between HRQOL and adverse dialysis outcomes (ie, death and hospitalization) also were assessed for all patients and by ethnicity. METHODS: Data are from the Dialysis Outcomes and Practice Patterns Study for 6,151 hemodialysis patients treated in 148 US dialysis facilities who filled out the Kidney Disease Quality of Life Short Form. We determined scores for three components of HRQOL: Physical Component Summary (PCS), Mental Component Summary (MCS), and Kidney Disease Component Summary (KDCS). Patients were classified by ethnicity as Hispanic and five non-Hispanic categories: white, African American, Asian, Native American, and other. Multiple linear regression models were used to estimate differences in HRQOL scores among ethnic groups, using whites as the referent category. Cox regression models were used for associations between HRQOL and outcomes. Regression models were adjusted for sociodemographic variables, delivered dialysis dose (equilibrated Kt/V), body mass index, years on dialysis therapy, and several laboratory/comorbidity variables. RESULTS: Compared with whites, African Americans showed higher HRQOL scores for all three components (MCS, PCS, and KDCS). Asians had higher adjusted PCS scores than whites, but did not differ for MCS or KDCS scores. Compared with whites, Hispanic patients had significantly higher PCS scores and lower MCS and KDCS scores. Native Americans showed significantly lower adjusted MCS scores than whites. The three major components of HRQOL were significantly associated with death and hospitalization for the entire pooled population, independent of ethnicity. CONCLUSION: The data indicate important differences in HRQOL among patients of different ethnic groups in the United States. Furthermore, HRQOL scores predict death and hospitalization among these patients.