Peritoneal Dialysis-Associated Peritonitis Trends Using Medicare Claims Data, 2013-2017.

RATIONALE & OBJECTIVE: The occurrence and consequences of peritoneal dialysis (PD)-associated peritonitis limit its use in populations with kidney failure. Studies of large clinical populations may enhance our understanding of peritonitis. To facilitate these studies we developed an approach to measuring peritonitis rates using Medicare claims data to characterize peritonitis trends and identify its clinical risk factors. STUDY DESIGN: Retrospective cohort study of PD-associated peritonitis. SETTING & PARTICIPANTS: US Renal Data System standard analysis files were used for claims, eligibility, modality, and demographic information. The sample consisted of patients receiving PD treated at some time between 2013 and 2017 who were covered by Medicare fee-for-service (FFS) insurance with paid claims for dialysis or hospital services. EXPOSURES/PREDICTORS: Peritonitis risk was characterized by year, age, sex, race, ethnicity, vintage of kidney replacement therapy, cause of kidney failure, and prior peritonitis episodes. OUTCOME: The major outcome was peritonitis, identified using ICD-9 and ICD-10 diagnosis codes. Closely spaced peritonitis claims (30 days) were aggregated into 1 peritonitis episode. ANALYTICAL APPROACH: Patient-level risk factors for peritonitis were modeled using Poisson regression. RESULTS: We identified 70,271 peritonitis episodes from 396,289 peritonitis claims. Although various codes were used to record an episode of peritonitis, none was used predominantly. Peritonitis episodes were often identified by multiple aggregated claims, with the mean and median claims per episode being 5.6 and 2, respectively. We found 40% of episodes were exclusively outpatient, 9% exclusively inpatient, and 16% were exclusively based on codes that do not clearly distinguish peritonitis from catheter infections/inflammation ("catheter codes"). The overall peritonitis rate was 0.54 episodes per patient-year (EPPY). The rate was 0.45 EPPY after excluding catheter codes and 0.35 EPPY when limited to episodes that only included claims from nephrologists or dialysis providers. The peritonitis rate declined by 5%/year and varied by patient factors including age (lower rates at higher ages), race (Black > White>Asian), and prior peritonitis episodes (higher rate with each prior episode). LIMITATIONS: Coding heterogeneity indicates a lack of standardization. Episodes based exclusively on catheter codes could represent false positives. Peritonitis episodes were not validated against symptoms or microbiologic data. CONCLUSIONS: PD-associated peritonitis rates decline over time and were lower among older patients. A claims-based approach offers a promising framework for the study of PD-associated peritonitis.

International peritoneal dialysis training practices and the risk of peritonitis.

BACKGROUND: The effects of training practices on outcomes of patients receiving peritoneal dialysis (PD) are poorly understood and there is a lack of evidence informing best training practices. This prospective cohort study aims to describe and compare international PD training practices and their association with peritonitis. METHODS: Adult patients on PD <3 months participating in the Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS) were included. Training characteristics (including duration, location, nurse affiliation, modality, training of family members, use of individual/group training and use of written/oral competency assessments) were reported at patient and facility levels. The hazard ratio (HR) for time to first peritonitis was estimated using Cox models, adjusted for selected patient and facility case-mix variables. RESULTS: A total of 1376 PD patients from 120 facilities across seven countries were included. Training was most commonly performed at the facility (81%) by facility-affiliated nurses (87%) in a 1:1 setting (79%). In the UK, being trained by both facility and third-party nurses was associated with a reduced peritonitis risk [adjusted HR 0.31 (95% confidence interval 0.15-0.62) versus facility nurses only]. However, this training practice was utilized in only 5 of 14 UK facilities. No other training characteristics were convincingly associated with peritonitis risk. CONCLUSIONS: There was no evidence to support that peritonitis risk was associated with when, where, how or how long PD patients are trained.

Variation in Peritoneal Dialysis-Related Peritonitis Outcomes in the Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS).

RATIONALE & OBJECTIVE: Peritoneal dialysis (PD)-associated peritonitis is a significant PD-related complication. We describe the likelihood of cure after a peritonitis episode, exploring its association with various patient, peritonitis, and treatment characteristics. STUDY DESIGN: Observational prospective cohort study. SETTING & PARTICIPANTS: 1,631 peritonitis episodes (1,190 patients, 126 facilities) in Australia, New Zealand, Canada, Japan, Thailand, the United Kingdom, and the United States. EXPOSURE: Patient characteristics (demographics, patient history, laboratory values), peritonitis characteristics (organism category, concomitant exit-site infection), dialysis center characteristics (use of icodextrin and low glucose degradation product solutions, policies regarding antibiotic self-administration), and peritonitis treatment characteristics (antibiotic used). OUTCOME: Cure, defined as absence of death, transfer to hemodialysis (HD), PD catheter removal, relapse, or recurrent peritonitis within 50 days of a peritonitis episode. ANALYTICAL APPROACH: Mixed-effects logistic models. RESULTS: Overall, 65% of episodes resulted in a cure. Adjusted odds ratios (AOR) for cure were similar across countries (range, 54%-68%), by age, sex, dialysis vintage, and diabetes status. Compared with Gram-positive peritonitis, the odds of cure were lower for Gram-negative (AOR, 0.41 [95% CI, 0.30-0.57]), polymicrobial (AOR, 0.30 [95% CI, 0.20-0.47]), and fungal (AOR, 0.01 [95% CI, 0.00-0.07]) peritonitis. Odds of cure were higher with automated PD versus continuous ambulatory PD (AOR, 1.36 [95% CI, 1.02-1.82]), facility icodextrin use (AOR per 10% greater icodextrin use, 1.06 [95% CI, 1.01-1.12]), empirical aminoglycoside use (AOR, 3.95 [95% CI, 1.23-12.68]), and ciprofloxacin use versus ceftazidime use for Gram-negative peritonitis (AOR, 5.73 [95% CI, 1.07-30.61]). Prior peritonitis episodes (AOR, 0.85 [95% CI, 0.74-0.99]) and concomitant exit-site infection (AOR, 0.41 [95% CI, 0.26-0.64]) were associated with a lower odds of cure. LIMITATIONS: Sample selection may be biased and generalizability may be limited. Residual confounding and confounding by indication limit inferences. Use of facility-level treatment variables may not capture patient-level treatments. CONCLUSIONS: Outcomes after peritonitis vary by patient characteristics, peritonitis characteristics, and modifiable peritonitis treatment practices. Differences in the odds of cure across infecting organisms and antibiotic regimens suggest that organism-specific treatment considerations warrant further investigation.

Peritoneal Dialysis-Related Infection Rates and Outcomes: Results From the Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS).

RATIONALE & OBJECTIVE: Peritoneal dialysis (PD)-related peritonitis carries high morbidity for PD patients. Understanding the characteristics and risk factors for peritonitis can guide regional development of prevention strategies. We describe peritonitis rates and the associations of selected facility practices with peritonitis risk among countries participating in the Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS). STUDY DESIGN: Observational prospective cohort study. SETTING & PARTICIPANTS: 7,051 adult PD patients in 209 facilities across 7 countries (Australia, New Zealand, Canada, Japan, Thailand, United Kingdom, United States). EXPOSURES: Facility characteristics (census count, facility age, nurse to patient ratio) and selected facility practices (use of automated PD, use of icodextrin or biocompatible PD solutions, antibiotic prophylaxis strategies, duration of PD training). OUTCOMES: Peritonitis rate (by country, overall and variation across facilities), microbiology patterns. ANALYTICAL APPROACH: Poisson rate estimation, proportional rate models adjusted for selected patient case-mix variables. RESULTS: 2,272 peritonitis episodes were identified in 7,051 patients (crude rate, 0.28 episodes/patient-year). Facility peritonitis rates were variable within each country and exceeded 0.50/patient-year in 10% of facilities. Overall peritonitis rates, in episodes per patient-year, were 0.40 (95% CI, 0.36-0.46) in Thailand, 0.38 (95% CI, 0.32-0.46) in the United Kingdom, 0.35 (95% CI, 0.30-0.40) in Australia/New Zealand, 0.29 (95% CI, 0.26-0.32) in Canada, 0.27 (95% CI, 0.25-0.30) in Japan, and 0.26 (95% CI, 0.24-0.27) in the United States. The microbiology of peritonitis was similar across countries, except in Thailand, where Gram-negative infections and culture-negative peritonitis were more common. Facility size was positively associated with risk for peritonitis in Japan (rate ratio [RR] per 10 patients, 1.07; 95% CI, 1.04-1.09). Lower peritonitis risk was observed in facilities that had higher automated PD use (RR per 10 percentage points greater, 0.95; 95% CI, 0.91-1.00), facilities that used antibiotics at catheter insertion (RR, 0.83; 95% CI, 0.69-0.99), and facilities with PD training duration of 6 or more (vs <6) days (RR, 0.81; 95% CI, 0.68-0.96). Lower peritonitis risk was seen in facilities that used topical exit-site mupirocin or aminoglycoside ointment, but this association did not achieve conventional levels of statistical significance (RR, 0.79; 95% CI, 0.62-1.01). LIMITATIONS: Sampling variation, selection bias (rate estimates), and residual confounding (associations). CONCLUSIONS: Important international differences exist in the risk for peritonitis that may result from varied and potentially modifiable treatment practices. These findings may inform future guidelines in potentially setting lower maximally acceptable peritonitis rates.

No Difference in Average Interdialytic Weight Gain Observed in a Randomized Trial With a Technology-Supported Behavioral Intervention to Reduce Dietary Sodium Intake in Adults Undergoing Maintenance Hemodialysis in the United States: Primary Outcomes of the BalanceWise Study.

OBJECTIVE: To evaluate the efficacy of behavioral counseling combined with technology-based self-monitoring for sodium restriction in hemodialysis (HD) patients. DESIGN: Randomized clinical trial. SUBJECTS: English literate adults undergoing outpatient, in-center intermittent HD for at least 3 months. INTERVENTIONS: Over a 16-week period, both the intervention and the attention control groups were shown 6 educational modules on the HD diet. The intervention group also received social cognitive theory-based behavioral counseling and monitored their diets daily using handheld computers. MAIN OUTCOME MEASURES: Average daily interdialytic weight gain (IDWGA) was calculated for every week of HD treatment over the observation period by subtracting the post-dialysis weight at the previous treatment time (t-1) from the pre-dialysis weight at the current treatment time (t), dividing by the number of days between treatments. Three 24-hour dietary recalls were obtained at baseline, 8 weeks, and 16 weeks and evaluated using the Nutrient Data System for Research. RESULTS: A total of 179 participants were randomized, and 160 (89.4%) completed final measurements. IDWGA did not differ significantly by treatment group at any time point considered (P > .79 for each). A significant differential change in dietary sodium intake observed at 8 weeks (-372 mg/day; P = .05) was not sustained at 16 weeks (-191 mg/day; P = .32). CONCLUSION: The BalanceWise Study intervention appeared to be feasible and acceptable to HD patients although IDWGA was unchanged and the desired behavioral changes observed at 8 weeks were not sustained. Unmeasured factors may have contributed to the mixed findings, and further research is needed to identify the appropriate patients for such interventions.

Effects of an intervention to improve communication about end-of-life care among African Americans with chronic kidney disease.

The prevalence of and mortality from chronic kidney disease (CKD) are high among African Americans. Interventions to improve knowledge of the likely illness course and the benefits and risks of life-sustaining treatment at the end-of-life are needed for African Americans with CKD and their surrogate decision makers. Nineteen African Americans with stage 5 CKD and their surrogates were randomized to either patient-centered advance care planning (PC-ACP) or usual care. PC-ACP dyads showed greater improvement in congruence in end-of-life treatment preferences (p < .05) and higher perceived quality of communication (p < .05) than do control dyads, but the two groups did not differ on other primary outcomes or acceptability measures, such as perceptions of cultural appropriateness. At posttest, 80% of patients in the intervention group reported that they would choose to continue all life-sustaining treatments in a situation of a low chance of survival, whereas 28.6% of patients in the control group reported that they would make that choice. At posttest, 90% of patients in the intervention group reported that they would choose to undergo cardiopulmonary resuscitation even if the chance of surviving the attempt would be low, whereas 57% of patients in the control group reported that they would make that choice. PC-ACP can be effective in improving patient and surrogate congruence in end-of-life treatment preferences. However, the results suggest a need for further improvements in the intervention to enhance cultural appropriateness for African Americans with CKD.

Subjective and objective sleep quality in patients on conventional thrice-weekly hemodialysis: comparison with matched controls from the sleep heart health study.

BACKGROUND: Studies examining sleep in the hemodialysis (HD) population have largely lacked an adequate comparison group. It therefore is uncertain whether poor sleep quality in the HD population reflects age, chronic health conditions, or effects of conventional HD therapy. STUDY DESIGN: Cross-sectional matched-group study. SETTING & PARTICIPANTS: Forty-six in-center HD patients were compared with 137 community participants participating in the Sleep Heart Health Study matched for age, sex, body mass index, and race. PREDICTOR: HD patients compared with community-dwelling non-HD participants. OUTCOMES & MEASUREMENTS: Home unattended polysomnography was performed and scored by using similar protocols. Sleep habits and sleepiness were assessed by using the Sleep Habits Questionnaire and Epworth Sleepiness Scale. RESULTS: Average age of study samples was 63 years, 72% were white, and average body mass index was 28 +/- 5 kg/m(2). HD patients were significantly more likely than community participants to have short sleep (odds ratio, 3.27; 95% confidence interval, 1.16 to 9.25) and decreased sleep efficiency (odds ratio, 5.5; 95% confidence interval, 1.5 to 19.6). HD patients reported more difficulty getting back to sleep (odds ratio, 2.25; 95% confidence interval, 1.11 to 4.60) and waking up too early (odds ratio, 2.39; 95% confidence interval, 1.01 to 5.66). There was no association between polysomnography sleep time and self-reported sleep time (r = 0.09; P = 0.6) or between the Epworth Sleepiness Scale and severity of sleep apnea (r = 0.10; P = 0.5) in the HD population. LIMITATIONS: The study was limited to participants older than 45 years. CONCLUSIONS: Kidney failure treated with thrice-weekly HD is significantly associated with poor subjective and objective sleep quality.

Sleep apnea in patients on conventional thrice-weekly hemodialysis: comparison with matched controls from the Sleep Heart Health Study.

Sleep-disordered breathing (SDB) has been noted commonly in hemodialysis (HD) patients, but it is not known whether this is related directly to the treatment of kidney failure with HD or to the higher prevalence of obesity and older age. Forty-six HD patients were compared with 137 participants from the Sleep Heart Health Study (SHHS) who were matched for age, gender, body mass index (BMI), and race. Home unattended polysomnography was performed and scored using similar protocols. The study sample was 62.7 +/- 10.1 yr, was predominantly male (72%) and white (63%), and had an average BMI of 28 +/- 5.3 kg/m(2). The HD sample had a higher systolic BP (137 versus 121 mmHg; P < 0.01) and a higher prevalence of diabetes (33 versus 9%; P < 0.01) and cardiovascular disease (33 versus 13%; P < 0.01) compared with the SHHS sample. The HD group had significantly less sleep time (320 versus 379 min; P < 0.0001) but similar sleep efficiency. HD patients had a higher frequency of arousals per hour (25.1 versus 17.1; P < 0.0001) and apnea-hypopneas per hour (27.2 versus 15.2; P < 0.0001) and greater percentage of the total sleep time below an oxygen saturation of 90% (7.2 versus 1.8; P < 0.0001). HD patients were more likely to have severe SDB (>30 respiratory events per hour) compared with the SHHS sample (odds ratio 4.07; 95% confidence interval 1.83 to 9.07). There was a strong association of HD with severe SDB and nocturnal hypoxemia independent of age, BMI, and the higher prevalence of chronic disease. The potential mechanisms for the higher likelihood of SDB in the HD population must be identified to provide specific prevention and therapy.