Comparative Effectiveness of mRNA-based BNT162b2 Vaccine versus Adenovirus Vector-Based Ad26.COV2.S Vaccine for the Prevention of COVID-19 among Dialysis Patients.

BACKGROUND: Studies have demonstrated that mRNA-based SARS-CoV-2 vaccines are highly effective among patients on dialysis. Because individual vaccines may be differentially available or acceptable to patients, it is important to understand comparative effectiveness relative to other vaccines, such those on the basis of adenovirus technologies. METHODS: In this retrospective study, we compared the clinical effectiveness of adenovirus vector-based Ad26.COV2.S (Janssen/Johnson & Johnson) to mRNA-based BNT162b2 (Pfizer/BioNTech) in a contemporary cohort of patients on dialysis. Patients who received a first BNT162b2 dose were matched 1:1 to Ad26.COV2.S recipients on the basis of date of first vaccine receipt, US state of residence, site of dialysis care (in-center versus home), history of COVID-19, and propensity score. The primary outcome was the comparative rate of COVID-19 diagnoses starting in the 7th week postvaccination. In a subset of consented patients who received Ad26.COV2.S, blood samples were collected ≥28 days after vaccination and anti-SARS-CoV-2 immunoglobulin G antibodies were measured. RESULTS: A total of 2572 matched pairs of patients qualified for analysis. Cumulative incidence rates of COVID-19 did not differ for BNT162b2 versus Ad26.COV2.S. No differences were observed in peri-COVID-19 hospitalizations and deaths among patients receiving BNT162b2 versus Ad26.COV2.S, who were diagnosed with COVID-19 during the at-risk period. Results were similar when excluding patients with a history of COVID-19, in subgroup analyses restricted to patients who completed the two-dose BNT162b2 regimen, and in patients receiving in-center hemodialysis. SARS-CoV-2 antibodies were detected in 59.4% of 244 patients who received Ad26.COV2.S. CONCLUSIONS: In a large real-world cohort of patients on dialysis, no difference was detected in clinical effectiveness of BNT162b2 and Ad26.COV2.S over the first 6 months postvaccination, despite an inconsistent antibody response to the latter.

Urgent-start peritoneal dialysis: Association with outcomes.

The majority of end-stage kidney disease (ESKD) patients start dialysis without adequate pre-dialysis planning. Of these patients, the vast majority initiate in-centre haemodialysis using a central venous catheter (ICHD-CVC). A minority utilise urgent-start peritoneal dialysis (USPD), whereby a peritoneal dialysis catheter is placed and used for dialysis without the usual 2-4-week waiting period. In this multicentre, retrospective study of adult patients initiating dialysis during 2018, we compared outcomes among patients utilising these two dialysis initiation routes. Patients who initiated dialysis via ICHD-CVC were matched 1:1 to patients who utilised USPD on the basis of aetiology of ESKD, race, diabetes status and insurance type. Hospitalisation and mortality were evaluated from dialysis initiation through the first of death, transplant, loss to follow-up or study end (30 June 2019). Outcomes were compared using models adjusted for age and sex. A total of 717 USPD patients were matched to ICHD-CVC patients. During follow-up, USPD patients were hospitalised at a rate of 1.21 admissions/patient-year (pt-yr) versus 1.51 admissions/pt-yr for ICHD-CVC. This corresponded to a 24% lower rate of hospitalisation among USPD patients (adjusted incidence rate ratio 0.76, 95% confidence interval [CI] 0.65-0.88). Mortality rates were 0.08 and 0.11 deaths/pt-yr among USPD patients and ICHD-CVC patients, respectively (adjusted hazard ratio 0.84, 95% CI 0.62, 1.15). These findings suggest that more widespread adoption of USPD may be beneficial among patients with limited pre-dialysis planning.

Predicting hospitalizations for patients with chronic kidney disease.

OBJECTIVES: Patients with chronic kidney disease (CKD) are at higher risk of being admitted to the hospital than the general population. Hospitalizations in patients with CKD are associated with higher medical costs and increased morbidity and mortality. Identification of patients with CKD who are at greatest risk of hospitalization may hold promise to improve clinical outcomes and enable judicious allocation of health care resources. STUDY DESIGN: Retrospective, observational cohort study. METHODS: Medicare Part A and Part B claims from calendar years 2017 and 2018 from 50,000 unique patients with a diagnosis of stage 3 to 5 CKD were used for this study. Data were split into training (n = 40,000) and test (n = 10,000) sets. A variety of model types were built to predict all-cause hospitalization within 90 days. RESULTS: The final model was a gradient-boosting machine with 399 input terms. The model demonstrated good ability to discriminate (area under the curve [AUC] for the receiver operating characteristic curve = 0.73), which was stable when tested in the test set (AUC = 0.73). The positive predictive value in the test set was 0.306, 0.240, and 0.216 at the 10%, 20%, and 30% thresholds, respectively. The sensitivity in the test set was 0.288, 0.453, and 0.609 at the 10%, 20%, and 30% thresholds, respectively. CONCLUSIONS: We developed an algorithm that uses medical claims to identify Medicare patients with CKD stages 3 to 5 who are at highest risk of being hospitalized in the near term. This algorithm could be used as a decision support tool for clinical programs focusing on management of patient populations with CKD.

Factors Associated with County-Level Variation in the Prescription of Statins.

BACKGROUND: The American College of Cardiology/American Heart Association recommends statins for adults aged 40-75 years with a cardiovascular disease risk factor and a 10-year risk of cardiovascular events of 7.5%-19.9%. OBJECTIVE: To examine the association of county-level social determinant measures of health and composition of health services with use of statin prescriptions under Medicare Part D. METHODS: We used 2013 Medicare Part D prescriber county-level data to construct 2 measures of statin use: (1) statin beneficiaries ÷ total beneficiaries (prevalence [ßPR]) and (2) statin days supplied ÷ (total beneficiaries × 365; adequacy of supply [ßAS]). We used multivariable regression to estimate the association of each measure with county-level demographics and health service measures. RESULTS: A 1 standard deviation (SD) increase in the proportion of African Americans living in a county is associated with a 0.096 SD decrease in adequacy of supply (ßAS = -0.096; 95% CI = -0.14 to -0.06). The proportion of county residents aged 65+ years who are female was associated with higher prevalence and adequacy of supply (ßPR = 0.06; 95% CI = 0.02 to 0.11; ßAS = 0.09; 95% CI = 0.05 to 0.14). Counties with higher proportions of Medicare Part D prescription expenditures receiving low-income subsidies had lower adequacy of supply (ßAS = -0.28; 95% CI = -0.32 to -0.23). Counties with a higher proportion of Medicare Part D prescribers who are nurse practitioners was associated with lower prevalence and adequacy of supply (ßPR = -0.39; 95% CI = -0.44 to -0.35; ßAS = -0.42; 95% CI = -0.47 to -0.37). CONCLUSIONS: Race and ethnicity, income, and distribution of provider types were significantly associated with county-level variation in statin use, despite being unlikely to measure differences in actual medical need. Such variation more likely reflects predisposing and enabling factors potentially affected by social, economic, and public health policy. Tracking variation in county-level statin use associated with these factors could help policymakers assess progress in reducing health care disparities and better target program resources. DISCLOSURES: No funding was received for this work. Karpinski reports employment by Aetna, Anthem, and Ingenio-Rx. Vanness reports unrelated consulting fees from CHEORS, Evidera, BMS, Novartis, and Merck. Look has nothing to disclose.