Comparison of the efficacies of 1.0mm and 1.5mm silicone tubes for the treatment of nasolacrimal duct obstruction

This study was designed to compare the postoperative outcomes of bicanalicular intubation using different diameters of silicone tubes to treat post-saccal nasolacrimal duct obstruction. A total of 130 patients diagnosed with post-saccal obstruction who underwent endoscopic-assisted silicone tube intubation were included in the study. The patients were divided into two groups; those intubated with a 1.5-mm large diameter tube (Group LD) and those with a 1.0-mm normal diameter tube (Group ND). The patency rates of the two groups at one year after tube removal were compared using the Kaplan–Meier's curve and Restricted mean survival time (RMST) method with τ = 365 days. Results showed that the recurrence rate after tube removal was significantly lower in the LD group compared to the ND group (p = 0.001). The patency rates at one year after removal in the LD and ND group were 0.857 (0.754-0.919) and 0.739 (0.617-0.828), respectively. When comparing the patency rates by the RMST method at τ = 365 days, the RMST difference, RMST ratio, and RMTL ratio were higher in the LD group at p = 0.045, 0.052, and 0.046, respectively.

Comparison of the efficacies of 1.0mm and 1.5mm silicone tubes for the treatment of nasolacrimal duct obstruction

This study was designed to compare the postoperative outcomes of bicanalicular intubation using different diameters of silicone tubes to treat post-saccal nasolacrimal duct obstruction. A total of 130 patients diagnosed with post-saccal obstruction who underwent endoscopic-assisted silicone tube intubation were included in the study. The patients were divided into two groups; those intubated with a 1.5-mm large diameter tube (Group LD) and those with a 1.0-mm normal diameter tube (Group ND). The patency rates of the two groups at one year after tube removal were compared using the Kaplan–Meier's curve and Restricted mean survival time (RMST) method with τ = 365 days. Results showed that the recurrence rate after tube removal was significantly lower in the LD group compared to the ND group (p = 0.001). The patency rates at one year after removal in the LD and ND group were 0.857 (0.754-0.919) and 0.739 (0.617-0.828), respectively. When comparing the patency rates by the RMST method at τ = 365 days, the RMST difference, RMST ratio, and RMTL ratio were higher in the LD group at p = 0.045, 0.052, and 0.046, respectively.

Waiting Time for Second Kidney Transplantation and Mortality

Background and objectivesThe median kidney transplant half-life is 10–15 years. Because of the scarcity of donor organs and immunologic sensitization of candidates for retransplantation, there is a need for quantitative information on if and when a second transplantation is no longer associated with a lower risk of mortality compared with waitlisted patients treated by dialysis. Therefore, we investigated the association of time on waiting list with patient survival in patients who received a second transplantation versus remaining on the waiting list.Design, setting, participants, & measurementsIn this retrospective study using target trial emulation, we analyzed data of 2346 patients from the Austrian Dialysis and Transplant Registry and Eurotransplant with a failed first graft, aged over 18 years, and waitlisted for a second kidney transplantation in Austria during the years 1980–2019. The differences in restricted mean survival time and hazard ratios for all-cause mortality comparing the treatment strategies “retransplant” versus “remain waitlisted with maintenance dialysis” are reported for different waiting times after first graft loss.ResultsSecond kidney transplantation showed a longer restricted mean survival time at 10 years of follow-up compared with remaining on the waiting list (5.8 life months gained; 95% confidence interval, 0.9 to 11.1). This survival difference was diminished in patients with longer waiting time after loss of the first allograft; restricted mean survival time differences at 10 years were 8.0 (95% confidence interval, 1.9 to 14.0) and 0.1 life months gained (95% confidence interval, −14.3 to 15.2) for patients with waiting time for retransplantation of <1 and 8 years, respectively.ConclusionsSecond kidney transplant is associated with patient survival compared with remaining waitlisted and treatment by dialysis, but the survival difference diminishes with longer waiting time.

Comparison of the efficacies of 1.0mm and 1.5mm silicone tubes for the treatment of nasolacrimal duct obstruction

This study was designed to compare the postoperative outcomes of bicanalicular intubation using different diameters of silicone tubes to treat post-saccal nasolacrimal duct obstruction. A total of 130 patients diagnosed with post-saccal obstruction who underwent endoscopic-assisted silicone tube intubation were included in the study. The patients were divided into two groups; those intubated with a 1.5-mm large diameter tube (Group LD) and those with a 1.0-mm normal diameter tube (Group ND). The patency rates of the two groups at one year after tube removal were compared using the Kaplan–Meier's curve and Restricted mean survival time (RMST) method with τ = 365 days. Results showed that the recurrence rate after tube removal was significantly lower in the LD group compared to the ND group (p = 0.001). The patency rates at one year after removal in the LD and ND group were 0.857 (0.754-0.919) and 0.739 (0.617-0.828), respectively. When comparing the patency rates by the RMST method at τ = 365 days, the RMST difference, RMST ratio, and RMTL ratio were significantly higher in the LD group at p = 0.045, 0.052, and 0.046, respectively.

OP236 Evidence Synthesis Of Time-To-Event Outcomes In The Presence Of Non-Proportional Hazards

IntroductionSynthesis of clinical effectiveness is a well-established component of health technology assessment (HTA) combining data from multiple trials to obtain an overall pooled estimate of clinical effectiveness, which may inform an associated economic evaluation. Time-to-event outcomes are often synthesized using effect measures from Cox proportional hazards models assuming a constant hazard ratio over time. However, where treatment effects vary over time an assumption of proportional hazards is not always valid. Several methods have been proposed for synthesizing time-to-event outcomes in the presence of non-proportional hazards. However, guidance on choosing between these methods and the implications for HTA is lacking.MethodsWe applied five methods for estimating treatment effects from time-to-event outcomes, which relax the proportional hazards assumption to a network of melanoma trials, reporting overall survival: restricted mean survival time, an accelerated failure time generalized gamma model, piecewise exponential, fractional polynomial and Royston-Parmar models. We conducted a simulation study to compare these five methods. Simulated individual patient data was generated from a mixture Weibull distribution assuming a treatment-time interaction. Each simulated meta-analysis consisted of five trials with varying numbers of patients and length of follow-up across trials. For each model fitted to each dataset, we calculated the restricted mean survival time at the end of observed follow-up and following extrapolation to a 20-year time horizon.ResultsAll models fitted the melanoma data reasonably well with some variation in the treatment rankings and differences in the survival curves. The simulation study demonstrated the potential for different conclusions from different modelling approaches.ConclusionsThe restricted mean survival time, generalized gamma, piecewise exponential, fractional polynomial and Royston-Parmar models can all accommodate non-proportional hazards and differing lengths of trial follow-up within an evidence synthesis of time-to-event outcomes. Further work is needed in this area to extend the simulation study to the network meta-analysis setting and provide guidance on the key considerations for informing model choice for the purposes of HTA.

Thyroid disease and hepatocellular carcinoma survival. A Danish nationwide cohort study

Introduction Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer mortality worldwide. Recent animal studies suggest that thyroid hormone treatment improves HCC prognosis. The aim of this study was to describe the association between thyroid disease and HCC prognosis in humans. Methods We performed a nationwide cohort study including all persons with an HCC diagnosis from 2000-2018. Patients’ age, sex, HCC treatment, and diagnoses of thyrotoxicosis, nontoxic goitre, and myxoedema, were obtained from Danish national healthcare registries. We used regression models to examine the association between thyroid disease and mortality hazard and restricted mean survival time after HCC diagnosis, adjusting for confounding by sex and age. Results We included 4,812 patients with HCC and 107 patients with thyroid disease. Median follow-up time was 5 months (total 5,985 person-years). The adjusted mortality hazard ratio was 0.68 (95% CI 0.47-0.96) for thyrotoxicosis and 0.60 (95% CI 0.41-0.88) for nontoxic goitre. The restricted mean survival time during the five years following HCC diagnosis was 6.8 months (95% CI 1.1–12.6) longer for HCC patients with thyrotoxicosis than for patients without thyroid disease, and it was 6.9 months (95% CI 0.9–12.9) longer for HCC patients with nontoxic goitre than for patients without thyroid disease. Conclusions In this large nationwide cohort study, thyrotoxicosis and nontoxic goitre were associated with prolonged HCC survival.

Communicating About Mortality in Health Decision Support: ‘What and Why and When, and How and Where and Who’

The Covid-19 pandemic has only accelerated the need and desire to deal more openly with mortality, because the effect on survival is central to the comprehensive assessment of harms and benefits needed to meet a ‘reasonable patient’ legal standard. Taking the view that this requirement is best met through a multi-criterial decision support tool, we offer our preferred answers to the questions of What should be communicated about mortality in the tool, and How, given preferred answers to Who for, Who by, Why, When, and Where. Summary measures, including unrestricted Life Expectancy and Restricted Mean Survival Time are found to be reductionist and relative, and not as easy to understand and communicate as often asserted. Full lifetime absolute survival curves should be presented, even if they cannot be ‘evidence-based’ beyond trial follow-up limits, along with equivalent measures for other criteria in the (necessarily) multi-criterial decision. A decision support tool should relieve the reasonable person of the resulting calculation burden.