Donna L. Mapes

Development of the Kidney Disease Quality of Life (KDQOL) Instrument

This paper describes the Kidney Disease Quality of Life (KDQOLTM) Instrument (dialysis version), a self-report measure that includes a 36-item health survey as the generic core, supplemented with multi-item scales targeted at particular concerns of individuals with kidney disease and on dialysis (symptom/problems, effects of kidney disease on daily life, burden of kidney disease, cognitive function, work status, sexual function, quality of social interaction, sleep). Also included were multi-item measures of social support, dialysis staff encouragement and patient satisfaction, and a single-item overall rating of health. The KDQOLTM was administered to 165 individuals with kidney disease (52% female; 48% male; 47% White; 27% African-American; 11% Hispanic; 8% Asian; 4% Native American; and 3% other ethnicities), sampled from nine different outpatient dialysis centres located in Southern California, the Northwest, and the Midwest. The average age of the sample was 53 years (range from 22 to 87), and 10% were 75 years or older. Internal consistency reliability estimates for the 19 multi-item scales exceeded 0.75 for every measure except one. The mean scores for individuals in this sample on the 36-item health scales were lower than the general population by one-quarter (emotional well-being) to a full standard deviation (physical function, role limitations due to physical health, general health), but similar to scores for dialysis patients in other studies. Correlations of the KDQOLTM scales with number of hospital days in the last 6 months were statistically significant (p<0.05) for 14 of the 19 scales and number of medications currently being taken for nine of the scales. Results of this study provide support for the reliability and validity of the KDQOLTM.

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

ObjectiveTo identify modifiable factors associated with health-related quality of life (HRQOL) among chronic hemodialysis patients.MethodsAnalysis 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-SFTM), 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 Benjamin-Hochberg procedure was used to correct P-values for multiple comparisons.ResultsUnemployment 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.ConclusionAssociations 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.

A review of health-related quality-of-life measures used in end-stage renal disease

Health-related quality of life (HRQOL) is a critical issue in the treatment of end-stage renal disease (ESRD) patients. The variety of symptoms, comorbidities, and treatments of ESRD over the course of its chronic disease trajectory necessitate comprehensive assessment of the impact of interventions on HRQOL. A literature review of ESRD HRQOL studies was performed to provide an overview of the instruments used and to provide recommendations for HRQOL assessment in future studies. Instruments were classified based on the health domains they assess and whether they are generic or disease targeted. The instruments were judged in terms of their comprehensiveness, reliability, and validity.

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.

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.

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.

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.

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.

Development of subscales from the symptoms/problems and effects of kidney disease scales of the kidney disease quality of life instrument

BACKGROUND The Kidney Disease Quality of Life Instrument (KDQOL) was developed to provide clinicians with a comprehensive assessment of the important domains of health-related quality of life (HRQOL) for patients with end-stage renal disease who are undergoing hemodialysis. OBJECTIVE The purpose of this study was to develop subscales from the 55 items comprising the Symptoms/Problems and Effects of Kidney Disease scales of the KDQOL and to measure the internal consistency reliability of these subscales. METHODS The 55 items from the Symptoms/Problems and Effects of Kidney Disease scales were arranged into substantively meaningful clusters using an affinity mapping procedure. The resulting subscales were assessed for internal consistency reliability using data from a sample of 165 individuals with kidney disease who had completed the KDQOL. RESULTS Eleven multi-item subscales were identified: pain, psychological dependency, cognitive functioning, social functioning, dialysis-related symptoms, cardiopulmonary symptoms, sleep, energy, cramps, diet, and appetite. Four items (clotting or other problems with access site, high blood pressure, numbness in hands or feet, and blurred vision) were not included in any of these subscales. Internal consistency reliability estimates for the 11 subscales ranged from 0.66 to 0.92. These subscales correlated with the scales from the 36-Item Short-Form Health Survey as hypothesized (ie, corresponding pain, energy, and social functioning scales had the highest correlations). In addition, several subscales were significantly associated, as hypothesized, with other variables such as the number of disability days. CONCLUSIONS The results of this study further support the reliability and validity of the KDQOL. The 11 subscales identified yield more detailed information on the HRQOL of patients with kidney disease and provide a basis for specific improvements in the quality of care delivered to these patients.

Health-related quality of life and depression among participants in the DOPPS: predictors and associations with clinical outcomes.

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