RESUMEN
Rationale & Objective: This study describes the epidemiology, characteristics, and clinical outcomes of patients with focal segmental glomerulosclerosis (FSGS)-attributed kidney failure in the US Renal Data System (USRDS) during 2008-2018, and health care resource utilization and costs among those with Medicare-linked data. Study Design: This was a retrospective cohort study. Setting & Population: Patients with FSGS-attributed kidney failure in the USRDS were enrolled in the study. Outcomes: The outcomes were as follows: Prevalence and incidence, clinical and demographic characteristics, time to kidney transplant or death, health care resource utilization, and direct health care costs. Analytical Approach: Patients with FSGS as the primary cause of kidney failure were followed from USRDS registration (index date) until death or data end. Prevalence and incidence were calculated per 1,000,000 US persons. Patient characteristics at index and treatment modalities during follow-up were described. Time to kidney transplant or death was assessed with Kaplan-Meier and competing risk analyses. Health care resource utilization and costs were reported among patients with 1 year Medicare Part A+B coverage postindex, including (Medicare Coverage subgroup) or excluding (1-year Medicare Coverage subgroup) those who died. Results: The FSGS cohort and Medicare Coverage and 1-year Medicare Coverage subgroups included 25,699, 6,340, and 5,575 patients, respectively. Mean annual period prevalence and incidence rates of FSGS-attributed kidney failure were 87.6 and 7.5 per 1,000,000 US persons, respectively. Initial treatment for most patients was in-center hemodialysis (72.1%), whereas 7.3% received kidney transplant. Accounting for competing risk of death, year 1 and 5 kidney transplant rates were 15% and 34%, respectively. In the Medicare Coverage and 1-year Medicare Coverage subgroups, 76.6% and 74.2% required inpatient admission, 69.9% and 67.3% visited the emergency room, and mean monthly health care costs were $6,752 and $5,575 in the year postindex, respectively. Limitations: Drug costs may be underestimated because Medicare Part D coverage was not required; kidney acquisition costs were not available. Conclusions: FSGS-attributed kidney failure is associated with substantial clinical and economic burden, prompting the need for novel therapies for FSGS to delay kidney failure.
This study of patients in the US Renal Data System observed increasing prevalence and fluctuating incidence of focal segmental glomerulosclerosis (FSGS)-attributed kidney failure from 2008 to 2018. Patients experienced a high clinical burden, including more than 3 years of treatment with dialysis, one-third receiving a kidney transplant, and one-third dying during follow-up. In the first year after US Renal Data System registration, three-quarters of patients with Medicare coverage required hospitalization, and more than two-thirds visited the emergency room. The total annual health care costs were >$68,000 per patient with FSGS-attributed kidney failure, underscoring the high economic burden of this disorder and the treatments required to sustain life. Novel therapies for FSGS are needed to delay or ideally prevent the need dialysis and transplantation after kidney failure.
RESUMEN
Rationale & Objective: This study describes the epidemiology, characteristics, and outcomes of patients with immunoglobulin A nephropathy (IgAN)-attributed kidney failure in the US Renal Data System (USRDS) from 2008 to 2018, including health care resource utilization and costs among patients with Medicare-linked data. Study Design: Retrospective cohort study. Setting & Population: Patients with IgAN-attributed kidney failure in the USRDS. Outcomes: Prevalence/incidence, clinical/demographic characteristics, time to kidney transplant, and health care resource utilization and costs. Analytical Approach: Patients with IgAN as primary cause of kidney failure (IgAN cohort) were followed from USRDS registration (index date) until data end/death. Prevalence/incidence were calculated per 1,000,000 US persons. Demographic and clinical characteristics at index and treatment modality during follow-up were summarized. Time from index to kidney transplant was assessed using Kaplan-Meier and competing risk analyses. Health care resource utilization and health care costs were reported among patients with 1 year Medicare Part A+B coverage postindex, including or excluding those who died (Medicare Coverage and 1-year Medicare Coverage subgroups, respectively). Results: The IgAN cohort, Medicare Coverage, and 1-year Medicare Coverage subgroups included 10,101, 1,696, and 1,510 patients, respectively. Mean annual period prevalence and incidence of IgAN-attributed kidney failure were 39.3 and 2.9 per 1,000,000 US persons, respectively. Initial treatment was in-center hemodialysis (63.1%) or kidney transplant (15.1%). Year 1 and 5 kidney transplant rates were 5% and 17%, respectively, accounting for competing risk of death. In the Medicare Coverage and 1-year Medicare Coverage subgroups, 74.4% and 72.3%, respectively, required inpatient admission, 67.3% and 64.4%, respectively, visited the emergency room, and mean total health care costs were $6,293 (SD: $6,934) and $5,284 ($3,455), respectively, per-patient-per-month in the year postindex. Limitations: Drug costs may be underestimated as Medicare Part D coverage was not required; kidney acquisition costs were unavailable. Conclusions: IgAN-attributed kidney failure is associated with substantial clinical and economic burdens. Novel therapies for IgAN that delay kidney failure are needed.
This study of patients in the United States Renal Data System (USRDS) observed fluctuating incidence and increasing prevalence of immunoglobulin A nephropathy (IgAN)-attributed kidney failure from 2008 to 2018. Patients experienced a high clinical burden, with 63% receiving in-center dialysis and over 15% receiving transplantation as initial therapy. In the first year after USRDS registration, nearly three-quarters of patients with Medicare coverage required hospitalization, and around two-thirds visited the emergency room. The total annual health care costs were >$63,000 per patient with IgAN-attributed kidney failure, underscoring the high economic burden of this disorder and currently available treatments. Novel therapies for IgAN are needed to delay or prevent the need for costly dialysis and transplantation after kidney failure.
RESUMEN
Rationale & Objective: Among patients with IgA nephropathy (IgAN), proteinuria and decline in kidney function may be associated with increased economic burden. This study aimed to provide current information on the epidemiology and economic burden of IgAN in the United States. Study Design: Retrospective cohort study. Setting & Study Population: Overall, 9,984 patients in the Optum's Market Clarity database identified by the presence of at least 2 natural language processing-derived IgAN signs and disease and symptoms terms; 813 with linked claims data included in a health care resource utilization/cost subcohort. Predictor: High-risk proteinuria (≥1 g/d), chronic kidney disease (CKD) stage. Outcomes: Standardized prevalence, health care resource utilization, costs. Analytical Approach: Descriptive statistics for categorical and continuous variables. Direct standardization for prevalence estimation. Generalized linear models for health care resource utilization/costs, reported as per-patient-per-month (PPPM) costs in 2020 US dollars. Results: The estimated standardized US prevalence of IgAN (2016-2020) was 329.0 per 1,000,000 persons. High-risk proteinuria (≥1 vs <1 g/d) was associated with a higher mean PPPM number of outpatient visits (3.49 vs 1.74; P = 0.01) and pharmacy claims (3.79 vs 2.41; P = 0.01), contributing to higher mean total costs PPPM ($3,732 vs $1,457; P = 0.01). Furthermore, higher CKD stage was also associated with higher health care resource utilization (number of outpatient visits PPPM, number of pharmacy claims PPPM, proportion of patients with inpatient visits and emergency department visits; P < 0.001) and mean total cost PPPM (from $2,111 CKD stage 1 to $10,703 CKD stage 5/kidney failure; P < 0.001). Limitations: Generalizability outside of the catchment group for the database, missing data/errors inherent in retrospective database studies, relatively small sample size, use of Optum Market Clarity standardized pricing algorithms, exclusion of out-of-pocket costs. Conclusions: Health care resource utilization and costs were higher for IgAN patients with high-risk proteinuria and worsening kidney function. Treatments that reduce proteinuria and slow CKD disease progression may reduce the economic burden associated with IgAN. Plain-Language Summary: Immunoglobulin A nephropathy (IgAN) is a rare kidney disease. Over time, the kidneys may leak protein into the urine (proteinuria). IgAN can lead to kidney failure. Because IgAN is rare, it is hard to know how many people have it. This study used electronic health records to estimate the number of patients with IgAN in the United States, describe the characteristics of patients, and understand their treatments and the costs. The number of patients with IgAN increased between 2016 and 2020. The researchers think this is because doctors learned more about IgAN. Patients with severe disease used more health care resources and had higher costs. The authors believe treatments that slow kidney damage may reduce the cost of treating IgAN.
