A nationwide analysis of the treatment patterns, survival, and medical costs in Korean patients with relapsed or refractory diffuse large B-cell lymphoma.

Background: Approximately one-third of patients with diffuse large B-cell lymphoma (DLBCL) are refractory to treatment or experience relapse after initial therapy. Unfortunately, treatment options for older patients and those who experience relapse or become refractory to hematopoietic stem cell transplantation (HSCT) are limited. This nationwide population-based study aimed to identify treatment patterns, survival times, and treatment costs in patients with relapsed/refractory DLBCL (R/R DLBCL). Materials and methods: Between 2011 and 2020, data on patients with R/R DLBCL were retrieved from the Korean Health Insurance Review & Assessment Service, encompassing the entire population. We identified the treatment patterns for each treatment line using a Sankey diagram and calculated the median time to the subsequent treatment in line. Median overall and progression-free survival times were estimated using the Kaplan-Meier survival curves. Finally, the medical costs incurred during DLBCL treatment were calculated for each treatment line and the costs related to HSCT were summarized at the episode level. Results: A total of 864 patients with R/R DLBCL who received second-line treatment were identified, and a regimen of ifosfamide, carboplatin, and etoposide (ICE) was administered the most. Among them, 353 were refractory or relapsed cases that were treated with third-line treatments. The median times for second-line to third-line, third-line to fourth-line, fourth-line to fifth-line, and fifth-line to sixth-line treatment failures gradually decreased (3.93, 2.86, 1.81, and 1.38 months, respectively). The median overall survival time was 8.90 and 4.73 months following the second-line and third-line treatments, respectively. In the third-line treatment setting, the patients did not show a significant difference in survival time after HSCT. The median medical cost was $39,491 across all treatment lines including the cost of HSCT which was $22,054. Conclusion: The treatment patterns in patients with R/R DLBCL, especially at third-line treatments and thereafter, were complicated, and their prognosis was poor despite the high medical costs. Novel and effective treatment options are expected to improve the prognosis and alleviate the economic burden of patients with R/R DLBCL.

Clinical impact and economic burden of post-transplant infections following heart transplantation: A retrospective nationwide cohort study.

BACKGROUND: Post-transplant infections are associated with high mortality rates. This retrospective nationwide cohort study examined the incidence and risk factors of infections requiring hospitalization after heart transplantation and the associated economic burden. METHODS: The entire heart transplant recipients' data from the Korean Health Insurance Review and Assessment Service between 2013 and 2020 was used. We estimated the annual incidence of post-transplant infections and adjusted incidence rate ratios (aIRR) of risk factors for reported infections using the poisson generalized linear model. RESULTS: Among 1,030 heart transplant recipients (324 with and 706 without post-transplant infections), 0.45 post-transplant infections were reported annually, with respiratory tract infections constituting the highest proportion (0.16). The risk of post-transplant infections was high in recipients with renal failure (aIRR = 1.35; 95% confidence interval [CI], 1.05-1.75) or nosocomial infection (aIRR = 1.47; 95% CI, 1.15-1.87). Combination regimens, including mammalian target of rapamycin inhibitor (mTORi), did not differ significantly from the standard 3 drug regimen (aIRR = 1.16; 95% CI, 0.80-1.67). The risk of death was higher among recipients with post-transplant infections than in uninfected recipients (adjusted hazard ratio = 4.59; 95% CI, 2.19-9.65). The mean follow-up cost per patient per month was 2-fold higher in recipients with post-transplant infections than in uninfected recipients ($5,096 and $2,532, respectively; p < .001). CONCLUSIONS: mTORi combination, which reportedly maintains renal function, can be considered, as it does not increase the infection risk. Post-transplant infections present clinical and economic burdens, warranting careful observation of at-risk patients.

Optimal Indicator of Death for Using Real-World Cancer Patients' Data From the Healthcare System.

Background: Information on patient's death is a major outcome of health-related research, but it is not always available in claim-based databases. Herein, we suggested the operational definition of death as an optimal indicator of real death and aim to examine its validity and application in patients with cancer. Materials and methods: Data of newly diagnosed patients with cancer between 2006 and 2015 from the Korean National Health Insurance Service-National Sample Cohort data were used. Death indicators were operationally defined as follows: 1) in-hospital death (the result of treatment or disease diagnosis code from claims data), or 2) case wherein there are no claims within 365 days of the last claim. We estimated true-positive rates (TPR) and false-positive rates (FPR) for real death and operational definition of death in patients with high-, middle-, and low-mortality cancers. Kaplan-Meier survival curves and log-rank tests were conducted to determine whether real death and operational definition of death rates were consistent. Results: A total of 40,970 patients with cancer were recruited for this study. Among them, 12,604 patients were officially reported as dead. These patients were stratified into high- (lung, liver, and pancreatic), middle- (stomach, skin, and kidney), and low- (thyroid) mortality groups consisting of 6,626 (death: 4,287), 7,282 (1,858), and 6,316 (93) patients, respectively. The TPR was 97.08% and the FPR was 0.98% in the high mortality group. In the case of the middle and low mortality groups, the TPR (FPR) was 95.86% (1.77%) and 97.85% (0.58%), respectively. The overall TPR and FPR were 96.68 and 1.27%. There was no significant difference between the real and operational definition of death in the log-rank test for all types of cancers except for thyroid cancer. Conclusion: Defining deaths operationally using in-hospital death data and periods after the last claim is a robust alternative to identifying mortality in patients with cancer. This optimal indicator of death will promote research using claim-based data lacking death information.

Clinical manifestation, economic burden, and mortality in patients with transthyretin cardiac amyloidosis.

BACKGROUND: Transthyretin cardiac amyloidosis, also known as transthyretin cardiomyopathy (ATTR-CM) is a poorly-recognized disease with delayed diagnosis and poor prognosis. This nationwide population-based study aimed to identify disease manifestations, economic burden, and mortality of patients with ATTR-CM. METHODS: Data of newly diagnosed patients with ATTR-CM between 2013 and 2018 from the Korean National Health Insurance Service were used, covering the entire population. Patient characteristics included comorbidities, medical procedures, and medication. Healthcare resource utilization and medical costs were observed as measures of the economic burden. The Kaplan-Meier survival curve and years of potential life lost (YPLL) from the general population were estimated for disease burden with ATTR CM. RESULTS: A total of 175 newly diagnosed patients with ATTR-CM were identified. The most common cardiac manifestation was hypertension (51.3%), while the most common non-cardiac manifestation was musculoskeletal disease (68.0%). Mean medical costs at the post-cohort entry date were significantly higher than those at the pre-cohort entry date ($1,864 vs. $400 per patient per month (PPPM), p < 0.001). Of the total medical costs during the study period, the proportion of inpatients cost was 12.9 times higher than the outpatients cost ($1,730 and $134 PPPM, respectively). The median survival time was 3.53 years from the first diagnosis of ATTR-CM, and the mean (SD) YPLL was 13.0 (7.7). CONCLUSIONS: Patients with ATTR-CM had short survival and high medical costs. To reduce the clinical and economic burdens, carefully examining manifestations of disease in patients can help with early diagnosis and treatment.

Association between oseltamivir use and neuropsychiatric adverse events in influenza patients: a nationwide population-based cohort study.

Background: A potential risk of neuropsychiatric adverse events (NPAEs) of oseltamivir has remained controversial by retrospective cohort studies. This nationwide population-based cohort study aimed to assess the risk of NPAEs in influenza patients undergoing oseltamivir treatment (users) compared with a propensity score-matched cohort of patients not receiving oseltamivir (non-users). Research design and methods: Using the Korean National Health Service-Sample Cohort Database, patients diagnosed with incident influenza during 2003-2013 were divided into two cohorts: oseltamivir users and non-users. We calculated adjusted hazard ratios (aHRs) for the 5-day treatment course with oseltamivir using Cox regression analysis. Results: The incidence rate of NPAEs during 5-day oseltamivir treatment was 0.0029 and 0.0023 in oseltamivir users and non-users, respectively. The risk of NPAEs was different according to age, with an increased risk in patients aged 10-19 years (aHR 2.69, 95% CI 1.05-6.93) and a decreased risk in patients aged 0-9 years (aHR 0.46, 95% CI 0.24-0.88). The non-significant positive associations were observed in patients aged 20-64 years and those aged greater than 65 years. Conclusions: Although the reason for the inverse association in children aged 0-9 years is unknown, oseltamivir could increase the risk of NPAEs for children or adolescents aged greater than 10 years.