The global spread of coronavirus disease 2019 (COVID-19) continues in several jurisdictions, causing substantial strain to health care systems. The purpose of our study was to predict the effect of ...the COVID-19 pandemic on patient outcomes and use of hospital resources in Ontario, Canada.
We developed an individual-level simulation to model the flow of patients with COVID-19 through the hospital system in Ontario. We simulated different combined scenarios of epidemic trajectory and hospital health care capacity. Our outcomes included the number of patients who needed admission to the ward or to the intensive care unit (ICU) with or without the need for mechanical ventilation, number of days to resource depletion, number of patients awaiting resources and number of deaths.
We found that with effective early public health measures, hospital system resources would not be depleted. For scenarios with late or ineffective implementation of physical distancing, hospital resources would be depleted within 14-26 days, and in the worst case scenario, 13 321 patients would die while waiting for needed resources. Resource depletion would be avoided or delayed with aggressive measures to increase ICU, ventilator and acute care hospital capacities.
We found that without aggressive physical distancing measures, the Ontario hospital system would have been inadequately equipped to manage the expected number of patients with COVID-19 despite a rapid increase in capacity. This lack of hospital resources would have led to an increase in mortality. By slowing the spread of the disease using public health measures and by increasing hospital capacity, Ontario may have avoided catastrophic stresses to its hospitals.
Although measuring albuminuria is the preferred method for defining and staging chronic kidney disease (CKD), total urine protein or dipstick protein is often measured instead.
To develop equations ...for converting urine protein-creatinine ratio (PCR) and dipstick protein to urine albumin-creatinine ratio (ACR) and to test their diagnostic accuracy in CKD screening and staging.
Individual participant-based meta-analysis.
12 research and 21 clinical cohorts.
919 383 adults with same-day measures of ACR and PCR or dipstick protein.
Equations to convert urine PCR and dipstick protein to ACR were developed and tested for purposes of CKD screening (ACR ≥30 mg/g) and staging (stage A2: ACR of 30 to 299 mg/g; stage A3: ACR ≥300 mg/g).
Median ACR was 14 mg/g (25th to 75th percentile of cohorts, 5 to 25 mg/g). The association between PCR and ACR was inconsistent for PCR values less than 50 mg/g. For higher PCR values, the PCR conversion equations demonstrated moderate sensitivity (91%, 75%, and 87%) and specificity (87%, 89%, and 98%) for screening (ACR >30 mg/g) and classification into stages A2 and A3, respectively. Urine dipstick categories of trace or greater, trace to +, and ++ for screening for ACR values greater than 30 mg/g and classification into stages A2 and A3, respectively, had moderate sensitivity (62%, 36%, and 78%) and high specificity (88%, 88%, and 98%). For individual risk prediction, the estimated 2-year 4-variable kidney failure risk equation using predicted ACR from PCR had discrimination similar to that of using observed ACR.
Diverse methods of ACR and PCR quantification were used; measurements were not always performed in the same urine sample.
Urine ACR is the preferred measure of albuminuria; however, if ACR is not available, predicted ACR from PCR or urine dipstick protein may help in CKD screening, staging, and prognosis.
National Institute of Diabetes and Digestive and Kidney Diseases and National Kidney Foundation.
•This commentary discusses the different types of models that can be used for pandemic planning in response to coronavirus disease 2019 (COVID-19). This article reviews different types of ...transmission models for infectious diseases and health-system models based on decision-analysis principles.•We include steps to guide conceptualization of a health-system model with a transmission component to aid decision makers and support public health policy using our COVID-19 Resource Estimator model, which was developed to estimate hospital resources in Ontario, Canada.•This article will be of most interest to health care decision makers, methodologists, health service researchers, and specialists in knowledge translation as well as infectious diseases. While the pandemic has been controlled in some parts of the world, many experts suggest an inevitable second wave. This article will be timely to equip quantitative researchers and decision makers with a guide to understand how modeling and early collaboration can be useful in predicting future consequences of this pandemic and impacts of potential interventions.
•This study compares pars plana vitrectomy (PPV), scleral buckle (SB), and pneumatic retinopexy (PnR) as procedures for repair of primary noncomplex rhegmatogenous retinal detachment (RRD).•In an ...economic evaluation of simulated data for 100,000 adult patients, all 3 procedures were deemed to be cost-effective for repair of primary RRD. PPV was found to be the most cost-effective when compared to SB and PnR over a lifetime horizon at a $50,000/QALY threshold.•These results suggest that despite the higher associated cost compared to PnR, PPV and SB may be cost-effective treatment options for management of primary noncomplex RRD in adults.
To assess the cost-effectiveness of primary noncomplex rhegmatogenous retinal detachment (RRD) repair, comparing 3 different strategies, pars plana vitrectomy (PPV), scleral buckle (SB), and pneumatic retinopexy (PnR) from the health care payer perspective over a lifetime.
Model-based cost-utility analysis.
A simulated cohort of 100,000 adult patients (≥18 years old) requiring primary noncomplex RRD repair in theoretical surgical centers in the United States. Quality-adjusted life years (QALYs), lifetime costs (2022 United States dollars), and the incremental cost-effectiveness ratio (ICER) of the 3 interventions were projected over a lifetime horizon, with a cost-effectiveness threshold of ≤$50,000 per gained QALY.
Based on inputted parameters, the primary anatomical success was highest for PPV (95.00%) compared to SB (91.76%) and PnR (63.41%). The QALYs associated with PPV, SB, and PnR were (11.87, SD 1.62), (11.84, SD 1.63), and (11.59, SD 1.72), respectively. The incurred lifetime costs of RRD repair and associated postoperative surgeries for PPV, SB, and PnR were $4445.72 (SD 655.75), $4518.04 (662.92), and $3978.45 (728.50), respectively. Parameter-level simulations suggested that PPV was most likely to be the most cost-effective therapy compared to SB and PnR beyond a threshold of $3000/QALY. The incremental cost-effectiveness ratio for PPV compared to PnR was $1693.54. SB was dominant in all scenarios. Threshold analyses indicated that the success rate of PnR would have to be 100% and/or the cost would have to be $2000 or less over lifetime for it to be more cost-effective than PPV.
This study found PPV to be the most cost-effective primary procedure for RRD repair at a threshold of $50,000/QALY gained over a lifetime horizon from the health care payer perspective.
eGFR is a robust predictor of ESRD risk. However, the prognostic information gained from the past trajectory (slope) beyond that of the current eGFR is unclear. We examined 22 cohorts to determine ...the association of past slopes and current eGFR level with subsequent ESRD. We modeled hazard ratios as a spline function of slopes, adjusting for demographic variables, eGFR, and comorbidities. We used random effects meta-analyses to combine results across studies stratified by cohort type. We calculated the absolute risk of ESRD at 5 years after the last eGFR using the weighted average baseline risk. Overall, 1,080,223 participants experienced 5163 ESRD events during a mean follow-up of 2.0 years. In CKD cohorts, a slope of -6 versus 0 ml/min per 1.73 m(2) per year over the previous 3 years (a decline of 18 ml/min per 1.73 m(2) versus no decline) associated with an adjusted hazard ratio of ESRD of 2.28 (95% confidence interval, 1.88 to 2.76). In contrast, a current eGFR of 30 versus 50 ml/min per 1.73 m(2) (a difference of 20 ml/min per 1.73 m(2)) associated with an adjusted hazard ratio of 19.9 (95% confidence interval, 13.6 to 29.1). Past decline contributed more to the absolute risk of ESRD at lower than higher levels of current eGFR. In conclusion, during a follow-up of 2 years, current eGFR associates more strongly with future ESRD risk than the magnitude of past eGFR decline, but both contribute substantially to the risk of ESRD, especially at eGFR<30 ml/min per 1.73 m(2).
•A cost-effectiveness analysis was performed of preoperative topical antibiotic prophylaxis in cataract surgery.•General use of preoperative topical antibiotic prophylaxis is not ...cost-effective.•Prophylaxis would be cost-effective at a higher incidence of endophthalmitis and/or a lower price.
To determine the cost-effectiveness of preoperative topical antibiotic prophylaxis for the prevention of endophthalmitis following cataract surgery.
Cost-effectiveness analysis using a decision-analytic microsimulation model.
Preoperative topical antibiotic prophylaxis vs no-prophylaxis costs and effects were projected over a life-time horizon for a simulated cohort of 500 000 adult patients (≥18 years old) requiring cataract surgery in theoretical surgical centers in the United States. Efficacy and cost (2021 US dollars) values were obtained from the literature and discounted at 3% per year.
Based on inputted parameters, the mean incidence of endophthalmitis following cataract surgery for preoperative topical antibiotic prophylaxis vs no-prophylaxis was 0.034% (95% CI 0%-0.2%) and 0.042% (95% CI 0%-0.3%), respectively—an absolute risk reduction of 0.008%. The mean life-time costs for cataract surgery with prophylaxis and no-prophylaxis were $2486.67 (95% CI $2193.61-$2802.44) and $2409.03 (95% CI $2129.94-$2706.69), respectively. The quality-adjusted life-years (QALYs) associated with prophylaxis and no-prophylaxis were 10.33495 (95% CI 7.81629-12.38158) and 10.33498 (95% CI 7.81284-12.38316), respectively. Assuming a cost-effectiveness criterion of ≤$50 000 per QALY gained, the threshold analyses indicated that prophylaxis would be cost-effective if the incidence of endophthalmitis after cataract surgery was greater than 5.5% or if the price of the preoperative topical antibiotic prophylaxis was less than $0.75.
General use of preoperative topical antibiotic prophylaxis is not cost-effective compared with no-prophylaxis for the prevention of endophthalmitis following cataract surgery. Preoperative topical antibiotic prophylaxis, however, would be cost-effective at a higher incidence of endophthalmitis and/or a substantially lower price for prophylaxis.
Extrapolation of time-to-event data from clinical trials is commonly used in decision models for health technology assessment (HTA). The objective of this study was to assess performance of standard ...parametric survival analysis techniques for extrapolation of time-to-event data for a single event from clinical trials with limited data due to small samples or short follow-up.
Simulated populations with 50,000 individuals were generated with an exponential hazard rate for the event of interest. A scenario consisted of 5000 repetitions with six sample size groups (30-500 patients) artificially censored after every 10% of events observed. Goodness-of-fit statistics (AIC, BIC) were used to determine the best-fitting among standard parametric distributions (exponential, Weibull, log-normal, log-logistic, generalized gamma, Gompertz). Median survival, one-year survival probability, time horizon (1% survival time, or 99th percentile of survival distribution) and restricted mean survival time (RMST) were compared to population values to assess coverage and error (e.g., mean absolute percentage error).
The true exponential distribution was correctly identified using goodness-of-fit according to BIC more frequently compared to AIC (average 92% vs 68%). Under-coverage and large errors were observed for all outcomes when distributions were specified by AIC and for time horizon and RMST with BIC. Error in point estimates were found to be strongly associated with sample size and completeness of follow-up. Small samples produced larger average error, even with complete follow-up, than large samples with short follow-up. Correctly specifying the event distribution reduced magnitude of error in larger samples but not in smaller samples.
Limited clinical data from small samples, or short follow-up of large samples, produce large error in estimates relevant to HTA regardless of whether the correct distribution is specified. The associated uncertainty in estimated parameters may not capture the true population values. Decision models that base lifetime time horizon on the model's extrapolated output are not likely to reliably estimate mean survival or its uncertainty. For data with an exponential event distribution, BIC more reliably identified the true distribution than AIC. These findings have important implications for health decision modelling and HTA of novel therapies seeking approval with limited evidence.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To predict adverse kidney outcomes for use in optimizing medical management and clinical trial design.
In this meta-analysis of individual participant data, 43 cohorts (N = 1,621,817) from research ...studies, electronic medical records, and clinical trials with global representation were separated into development and validation cohorts. Models were developed and validated within strata of diabetes mellitus (presence or absence) and estimated glomerular filtration rate (eGFR; ≥60 or <60 mL/min/1.73 m2) to predict a composite of ≥40% decline in eGFR or kidney failure (i.e., receipt of kidney replacement therapy) over 2-3 years.
There were 17,399 and 24,591 events in development and validation cohorts, respectively. Models predicting ≥40% eGFR decline or kidney failure incorporated age, sex, eGFR, albuminuria, systolic blood pressure, antihypertensive medication use, history of heart failure, coronary heart disease, atrial fibrillation, smoking status, and BMI, and, in those with diabetes, hemoglobin A1c, insulin use, and oral diabetes medication use. The median C-statistic was 0.774 (interquartile range IQR = 0.753, 0.782) in the diabetes and higher-eGFR validation cohorts; 0.769 (IQR = 0.758, 0.808) in the diabetes and lower-eGFR validation cohorts; 0.740 (IQR = 0.717, 0.763) in the no diabetes and higher-eGFR validation cohorts; and 0.750 (IQR = 0.731, 0.785) in the no diabetes and lower-eGFR validation cohorts. Incorporating the previous 2-year eGFR slope minimally improved model performance, and then only in the higher-eGFR cohorts.
Novel prediction equations for a decline of ≥40% in eGFR can be applied successfully for use in the general population in persons with and without diabetes with higher or lower eGFR.
PURPOSE OF REVIEWChronic kidney disease (CKD) is strongly linked to premature cardiovascular disease, which is the leading cause of death before end-stage renal disease in these patients. Herein, we ...review recent literature from 2014 to 2015 that has advanced our understanding of cardiovascular outcomes in patients with advanced and/or progressive CKD.
RECENT FINDINGSWe focus on new data describing the mechanisms of cardiac death in patients with CKD as well as the novel associations between cardiac events and the competing risks of end-stage renal disease and pre-end-stage renal disease death. We review new controversies in multivessel revascularization of complex coronary artery disease in CKD and, finally, the treatment of systolic heart failure in advanced CKD, including the use of implantable defibrillator therapy.
SUMMARYMarked advances in the understanding of cardiovascular disease in CKD have occurred in the past year, namely from retrospective and registry data. Although exciting, these recent studies highlight the urgent need for randomized control trials to guide therapeutic decisions.
The Framingham Risk Score (FRS) and Pooled Cohort Equations (PCEs) overestimate risk in many contemporary cohorts.
This study sought to determine if recalibration of these scores using contemporary ...population-level data improves risk stratification for statin therapy.
Five-year FRS and PCEs were recalibrated using a cohort of Ontario residents alive January 1, 2011, who were 30 to 79 years of age without cardiovascular disease. Scores were externally validated in a primary care cohort of routinely collected electronic medical record data from January 1, 2010, to December 31, 2014. The relative difference in mean predicted and observed risk, number of statins avoided, and number needed to treat with statins to reduce a cardiovascular event at 5 years were reported.
The FRS was recalibrated in 6,938,971 Ontario residents (51.6% women, mean age 48 years) and validated in 71,450 individuals (56.1% women, mean age 52 years). Recalibration reduced overestimation from 109% to 49% for women and 131% to 32% for men. The recalibrated FRS was estimated to reduce statin prescriptions in up to 26 per 1,000 low-risk women and 80 per 1,000 low-risk men, as well as reduce the number needed to treat from 61 to 47 in women and from 53 to 41 in men. In contrast, after recalibration of the PCEs, risk remained overestimated by 217% in women and 128% in men.
Recalibration is a feasible solution to improve risk prediction but is dependent on the model being used. Recalibration of the FRS but not the PCEs reduced overestimation and may improve utilization of statins.
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