Multiple imputation for propensity score analysis with covariates missing at random: some clarity on within and across methods.

In epidemiology and social sciences, propensity score methods are popular for estimating treatment effects using observational data, and multiple imputation is popular for handling covariate missingness. However, how to appropriately use multiple imputation for propensity score analysis is not completely clear. This paper aims to bring clarity on the consistency (or lack thereof) of methods that have been proposed, focusing on the within approach (where the effect is estimated separately in each imputed dataset and then the multiple estimates are combined) and the across approach (where typically propensity scores are averaged across imputed datasets before being used for effect estimation). We show that the within method is valid and can be used with any causal effect estimator that is consistent in the full-data setting. Existing across methods are inconsistent, but a different across method that averages the inverse probability weights across imputed datasets is consistent for propensity score weighting. We also comment on methods that rely on imputing a function of the missing covariate rather than the covariate itself, including imputation of the propensity score and of the probability weight. Based on consistency results and practical flexibility, we recommend generally using the standard within method. Throughout, we provide intuition to make the results meaningful to the broad audience of applied researchers.

Survival disparities in non-Hispanic Black and White cervical cancer patients vary by histology and are largely explained by modifiable factors.

PURPOSE: We investigated racial disparities in survival by histology in cervical cancer and examined the factors contributing to these disparities. METHODS: Non-Hispanic Black and non-Hispanic White (hereafter known as Black and White) patients with stage I-IV cervical carcinoma diagnosed between 2004 and 2017 in the National Cancer Database were studied. Survival differences were compared using Cox modeling to estimate hazard ratio (HR) or adjusted HR (AHR) and 95% confidence interval (CI). The contribution of demographic, socioeconomic and clinical factors to the Black vs White differences in survival was estimated after applying propensity score weighting in patients with squamous cell carcinoma (SCC) or adenocarcinoma (AC). RESULTS: This study included 10,111 Black and 43,252 White patients with cervical cancer. Black patients had worse survival than White cervical cancer patients (HR = 1.40, 95% CI = 1.35-1.45). Survival disparities between Black and White patients varied significantly by histology (HR = 1.20, 95% CI = 1.15-1.24 for SCC; HR = 2.32, 95% CI = 2.12-2.54 for AC, interaction p < 0.0001). After balancing the selected demographic, socioeconomic and clinical factors, survival in Black vs. White patients was no longer different in those with SCC (AHR = 1.01, 95% CI 0.97-1.06) or AC (AHR = 1.09, 95% CI = 0.96-1.24). In SCC, the largest contributors to survival disparities were neighborhood income and insurance. In AC, age was the most significant contributor followed by neighborhood income, insurance, and stage. Diagnosis of AC (but not SCC) at ≥65 years old was more common in Black vs. White patients (26% vs. 13%, respectively). CONCLUSIONS: Histology matters in survival disparities and diagnosis at ≥65 years old between Black and White cervical cancer patients. These disparities were largely explained by modifiable factors.

Propensity score analysis of low-dose aspirin and bleeding complications in pregnancy.

OBJECTIVE: Low-dose aspirin (LDA) has been shown to reduce the risk of preterm pre-eclampsia and it has been suggested that it should be recommended for all pregnancies. However, some studies have reported an association between LDA and an increased risk of bleeding complications in pregnancy. Our aim was to evaluate the risk of placental abruption and postpartum hemorrhage (PPH) in patients for whom their healthcare provider had recommended prophylactic aspirin. METHODS: This multicenter cohort study included 72 598 singleton births at 19 hospitals in the USA, between January 2019 and December 2021. Pregnancies complicated by placenta previa/accreta, birth occurring at less than 24 weeks' gestation, multiple pregnancy or those with data missing for aspirin recommendation were excluded. Propensity scores were calculated using 20 features spanning sociodemographic factors, medical history, year and hospital providing care. The association between LDA recommendation and placental abruption or PPH was estimated by inverse-probability treatment weighting using the propensity scores. RESULTS: We included 71 627 pregnancies in the final analysis. Aspirin was recommended to 6677 (9.3%) and was more likely to be recommended for pregnant individuals who were 35 years or older (P < 0.001), had a body mass index of 30 kg/m2 or higher (P < 0.001), had prepregnancy hypertension (P < 0.001) and who had a Cesarean delivery (P < 0.001). Overall, 1.7% of the study cohort (1205 pregnancies) developed preterm pre-eclampsia: 1.3% in the no-aspirin and 5.8% in the aspirin group. After inverse-probability weighting with propensity scores, aspirin was associated with increased risk of placental abruption (adjusted odds ratio (aOR), 1.44 (95% CI, 1.04-2.00)) and PPH (aOR, 1.21 (95% CI, 1.05-1.39)). The aOR translated to a number needed to harm with LDA of 79 (95% CI, 43-330) for PPH and 287 (95% CI, 127-3151) for placental abruption. CONCLUSIONS: LDA recommendation in pregnancy was associated with increased risk for placental abruption and for PPH. Our results support the need for more research into aspirin use and bleeding complications in pregnancy before recommending it beyond the highest-risk pregnancies. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Low-Volume Acute Normovolemic Hemodilution Does Not Reduce Allogeneic Red Blood Cell Transfusion in Cardiac Surgery in the Modern Era of Patient Blood Management: A Propensity Score-Matched Cohort Study.

OBJECTIVES: Patients undergoing cardiac surgery often require blood transfusions, which are associated with increased morbidity and mortality. Patient blood management (PBM) strategies, including acute normovolemic hemodilution (ANH), have been implemented to minimize allogeneic transfusion requirements. Older studies suggested that ANH is associated with reduced transfusions; however, its effectiveness in the modern era of PBM remains unclear. DESIGN: This was a retrospective cohort study. SETTING: The study was held at a single university hospital. PARTICIPANTS: 542 patients who underwent elective cardiac surgery with cardiopulmonary bypass (CPB) using low-priming-volume circuits between January 2017 and March 2022. INTERVENTIONS: Patients who received ANH were matched with those who did not receive ANH, using propensity scores. MEASUREMENTS AND MAIN RESULTS: The primary outcome was the proportion of patients who received perioperative red blood cell (RBC) transfusion. Of the 542 eligible patients, 49 ANH cases were propensity-score matched to 97 controls. The median ANH volume was 450 mL (IQR, 400-800 mL). There was no significant difference in perioperative RBC transfusion rates between the 2 groups (24.5% in the ANH group vs 30.9% in the control group, p = 0.42). The odds ratio for perioperative RBC transfusion in the ANH group versus the control group was 0.72 (95% CI, 0.32-1.55, p = 0.42). CONCLUSIONS: Low-volume ANH was not associated with a significant reduction in perioperative allogeneic RBC transfusion during cardiac surgery with CPB using low-priming-volume circuits. The benefits of low-volume ANH in reducing the requirement for RBC transfusion in the modern era of PBM may be smaller than reported previously.

Real-world efficacy of adjuvant therapy for totally resected stage I lung adenocarcinoma patients with pathological high-risk factors: propensity score analysis.

BACKGROUND: We investigated the real-world efficacy of adjuvant therapy for stage I lung adenocarcinoma patients with pathological high-risk factors. METHODS: Study participants were enrolled from November 1, 2016 and December 31, 2020. Clinical bias was balanced by propensity score matching. Disease-free survival (DFS) outcomes were compared by Kaplan-Meier analysis. The Cox proportional hazards regression was used to identify survival-associated factors. p ≤ 0.05 was the threshold for statistical significance. RESULTS: A total of 454 patients, among whom 134 (29.5%) underwent adjuvant therapy, were enrolled in this study. One hundred and eighteen of the patients who underwent adjuvant therapy were well matched with non-treatment patients. Prognostic outcomes of the treatment group were significantly better than those of the non-treatment group, as revealed by Kaplan-Meier analysis after PSM. Differences in prevention of recurrence or metastasis between the targeted therapy and chemotherapy groups were insignificant. Adjuvant therapy was found to be positive prognostic factors, tumor size and solid growth patterns were negative. CONCLUSIONS: Adjuvant therapy significantly improved the DFS for stage I lung adenocarcinoma patients with high-risk factors. Larger prospective clinical trials should be performed to verify our findings.

Adjuvant chemotherapy for stage II and III gastric adenocarcinoma: A retrospective analysis with long-term follow-up.

BACKGROUND: Whether adjuvant chemotherapy should be different for patients with stage II and III gastric cancer is unknown. METHODS: We retrospectively analyzed the effects of adjuvant chemotherapy on the outcomes of 140 and 256 patients with stage II and III gastric cancer, respectively, between January 2008 and December 2018. Chemotherapies were stratified as fluoropyrimidine plus platinum versus fluoropyrimidine alone, tegafur/gimeracil/octeracil (S-1)-containing versus non-S-1-containing regimens, and S-1 plus cisplatin versus S-1 alone. RESULTS: The median age of patients was 67.0 (range 24.6-98.8) years. With a median follow-up of 105 months, recurrence occurred in 32 (22.9%) and 130 (50.8%) patients with stage II and III disease, respectively. Adjuvant chemotherapy was administered as fluoropyrimidine monotherapy to 68 (48.6%) and 73 (28.5%) patients, fluoropyrimidine plus platinum to 9 (6.4%) and 104 (40.6%) patients, and none to 63 (45.0%) and 79 (30.9%) patients with stage II and III gastric cancer, respectively. Doublet chemotherapy was associated with longer disease-free survival (DFS) (26.5 vs. 15.2 months, P = 0.001) and overall survival (OS) (41.2 vs. 22.0 months, P < 0.001) than fluoropyrimidine monotherapy for stage IIIB-IIIC disease. Furthermore, S-1-containing regimens prolonged DFS (57.4 vs. 21.9 months, P = 0.044) and OS (81.4 vs. 28.6 months, P = 0.023) compared with non-S-1-containing chemotherapy in stage III disease. CONCLUSION: Although fluoropyrimidine monotherapy is feasible for stage II-IIIA disease, doublet chemotherapy is significantly associated with longer survival than monotherapy for stage IIIB-IIIC disease. S-1-containing regimens might lead to longer survival than non-S-1-containing chemotherapy in stage III gastric cancer.

A Generalized Bootstrap Procedure of the Standard Error and Confidence Interval Estimation for Inverse Probability of Treatment Weighting.

The inverse probability of treatment weighting (IPTW) approach is commonly used in propensity score analysis to infer causal effects in regression models. Due to oversized IPTW weights and errors associated with propensity score estimation, the IPTW approach can underestimate the standard error of causal effect. To remediate this, bootstrap standard errors have been recommended to replace the IPTW standard error, but the ordinary bootstrap (OB) procedure might still result in underestimation of the standard error because of its inefficient resampling scheme and untreated oversized weights. In this paper, we develop a generalized bootstrap (GB) procedure for estimating the standard error and confidence intervals of the IPTW approach. Compared with the OB procedure and other three procedures in comparison, the GB procedure has the highest precision and yields conservative standard error estimates. As a result, the GB procedure produces short confidence intervals with highest coverage rates. We demonstrate the effectiveness of the GB procedure via two simulation studies and a dataset from the National Educational Longitudinal Study-1988 (NELS-88).

Unreliable Continuous Treatment Indicators in Propensity Score Analysis.

Propensity score analyses (PSA) of continuous treatments often operationalize the treatment as a multi-indicator composite, and its composite reliability is unreported. Latent variables or factor scores accounting for this unreliability are seldom used as alternatives to composites. This study examines the effects of the unreliability of indicators of a latent treatment in PSA using the generalized propensity score (GPS). A Monte Carlo simulation study was conducted varying composite reliability, continuous treatment representation, variability of factor loadings, sample size, and number of treatment indicators to assess whether Average Treatment Effect (ATE) estimates differed in their relative bias, Root Mean Squared Error, and coverage rates. Results indicate that low composite reliability leads to underestimation of the ATE of latent continuous treatments, while the number of treatment indicators and variability of factor loadings show little effect on ATE estimates, after controlling for overall composite reliability. The results also show that, in correctly specified GPS models, the effects of low composite reliability can be somewhat ameliorated by using factor scores that were estimated including covariates. An illustrative example is provided using survey data to estimate the effect of teacher adoption of a workbook related to a virtual learning environment in the classroom.

Balance diagnostics in propensity score analysis following multiple imputation: A new method.

The combination of propensity score analysis and multiple imputation has been prominent in epidemiological research in recent years. However, studies on the evaluation of balance in this combination are limited. In this paper, we propose a new method for assessing balance in propensity score analysis following multiple imputation. A simulation study was conducted to evaluate the performance of balance assessment methods (Leyrat's, Leite's, and new method). Simulated scenarios varied regarding the presence of missing data in the control or treatment and control group, and the imputation model with/without outcome. Leyrat's method was more biased in all the studied scenarios. Leite's method and the combine method yielded balanced results with lower mean absolute difference, regardless of whether the outcome was included in the imputation model or not. Leyrat's method had a higher false positive ratio and Leite's and combine method had higher specificity and accuracy, especially when the outcome was not included in the imputation model. According to simulation results, most of time, Leyrat's method and Leite's method contradict with each other on appraising the balance. This discrepancy can be solved using new combine method.

An outcome-wide analysis of the effects of diagnostic labeling of Alzheimer's disease and related dementias on social relationships.

INTRODUCTION: This study examines how receiving a dementia diagnosis influences social relationships by race and ethnicity. METHODS: Using data from the Health and Retirement Study (10 waves; 7,159 observations) of adults 70 years and older predicted to have dementia using Gianattasio-Power scores (91% accuracy), this study assessed changes in social support, engagement, and networks after a dementia diagnosis. We utilized quasi-experimental methods to estimate treatment effects and subgroup analyses by race/ethnicity. RESULTS: A diagnostic label significantly increased the likelihood of gaining social support but reduced social engagement and one measure of social networks. With some exceptions, the results were similar by race and ethnicity. DISCUSSION: Results suggest that among older adults with assumed dementia, being diagnosed by a doctor may influence social relationships in both support-seeking and socially withdrawn ways. This suggests that discussing services and supports at the time of diagnosis is important for healthcare professionals.

Confounding adjustment in the analysis of augmented randomized controlled trial with hybrid control arm.

The augmented randomized controlled trial (RCT) with hybrid control arm includes a randomized treatment group (RT), a smaller randomized control group (RC), and a large synthetic control (SC) group from real-world data. This kind of trial is useful when there is logistics and ethics hurdle to conduct a fully powered RCT with equal allocation, or when it is necessary to increase the power of the RCT by incorporating real-world data. A difficulty in the analysis of augmented RCT is that the SC and RC may be systematically different in the distribution of observed and unmeasured confounding factors, causing bias when the two control groups are analyzed together as hybrid controls. We propose to use propensity score (PS) analysis to balance the observed confounders between SC and RC. The possible bias caused by unmeasured confounders can be estimated and tested by analyzing propensity score adjusted outcomes from SC and RC. We also propose a partial bias correction (PBC) procedure to reduce bias from unmeasured confounding. Extensive simulation studies show that the proposed PS + PBC procedures can improve the efficiency and statistical power by effectively incorporating the SC into the RCT data analysis, while still control the estimation bias and Type I error inflation that might arise from unmeasured confounding. We illustrate the proposed statistical procedures with data from an augmented RCT in oncology.

Editor's Choice - Infra-inguinal Endovascular Revascularisation and Bypass Surgery for Chronic Limb Threatening Ischaemia: a Retrospective European Multicentre Cohort Study with Propensity Score Matching.

OBJECTIVE: The aim of this study was to compare the long term efficacy of lower limb bypass with that of endovascular treatment (EVT) in patients with chronic limb threatening ischaemia (CLTI). METHODS: This retrospective, multicentre study evaluated the outcomes of patients with CLTI who underwent first time infra-inguinal bypass or EVT. The primary outcome was to compare amputation free survival (AFS) rates between the two propensity score matched groups. The secondary outcome was to compare wound healing within the first six months. Major adverse events were compared according to the type of revascularisation. RESULTS: Overall, 793 patients fulfilled the eligibility criteria, from whom 236 propensity score matched pairs were analysed. The mean follow up was 52 months. The 236 bypass procedures included 190 autogenous bypass grafts (80.5%), 151 (64.0%) of which were infrapopliteal. Among the 236 EVT procedures, the target lesion was the femoropopliteal segment in 81 patients (34.3%), the femoropopliteal and infrapopliteal segments in 101 patients (42.8%), and the infrapopliteal segment in 54 patients (22.9%). AFS was significantly better in the bypass group at five years (60.5 ± 3.6%) compared with the EVT group (35.3 ± 3.6%) (p < .001). Major amputation occurred in 61 patients (25.8%) in the bypass group and 85 patients (36.0%) in the EVT group (HR 0.66, 95% CI 0.47 - 0.92; p = .014). The probability of healing was significantly better in the bypass group at six months compared with the EVT group (p = .003). The median length of stay was shorter for the EVT group (4 days) than for the bypass group (8 days) (p = .001). Urgent re-intervention and re-admission rates were high and did not differ significantly between the groups. CONCLUSION: This study has shown that lower limb bypass surgery offered a significantly higher probability of AFS and wound healing compared with EVT in patients with CLTI.

Propensity score analysis with missing data using a multi-task neural network.

BACKGROUND: Propensity score analysis is increasingly used to control for confounding factors in observational studies. Unfortunately, unavoidable missing values make estimating propensity scores extremely challenging. We propose a new method for estimating propensity scores in data with missing values. MATERIALS AND METHODS: Both simulated and real-world datasets are used in our experiments. The simulated datasets were constructed under 2 scenarios, the presence (T = 1) and the absence (T = 0) of the true effect. The real-world dataset comes from LaLonde's employment training program. We construct missing data with varying degrees of missing rates under three missing mechanisms: MAR, MCAR, and MNAR. Then we compare MTNN with 2 other traditional methods in different scenarios. The experiments in each scenario were repeated 20,000 times. Our code is publicly available at https://github.com/ljwa2323/MTNN . RESULTS: Under the three missing mechanisms of MAR, MCAR and MNAR, the RMSE between the effect and the true effect estimated by our proposed method is the smallest in simulations and in real-world data. Furthermore, the standard deviation of the effect estimated by our method is the smallest. In situations where the missing rate is low, the estimation of our method is more accurate. CONCLUSIONS: MTNN can perform propensity score estimation and missing value filling at the same time through shared hidden layers and joint learning, which solves the dilemma of traditional methods and is very suitable for estimating true effects in samples with missing values. The method is expected to be broadly generalized and applied to real-world observational studies.

Taking Oral Sulfate Tablets with Simethicone for Bowel Preparation Leads to Higher Adenoma Detection Rate than Polyethylene Glycol: A Propensity Score Analysis.

BACKGROUND: Efficient bowel preparation is essential for preventing colorectal cancer by improving endoscopic adenoma detection. Tablet for bowel preparation containing sulfate salts, OSTs (oral sulfate tablets), has been developed and it is gaining more popularity. However, its efficacy compared to standard preparation agent, PEG-AA (polyethylene glycol), has not been well discovered. We assessed the efficacy of PEG and OSTs using a real-time clinical data warehouse (CDW) model. METHODS: We performed a propensity score-matched (PSM) analysis of consecutive adult patients undergoing colonoscopy who received PEG-AA or OSTs prior to colonoscopy at a tertiary academic hospital. The endoscopic records of 992 adult patients were retrospectively analyzed. The clinical data warehouse collected data including bowel preparation, insertion time, observation time, and the detection of polyps and adenomas. Multivariate regression analysis was performed to reveal the factors associated with endoscopic outcomes. RESULTS: Among 992 patients included in the study, 770 and 222 patients received PEG-AA and OSTs, respectively. Among the propensity score-matched population (n = 1897), OSTs resulted in better bowel cleansing quality (8.16 vs 7.84, p = 0.014) and a higher adenoma detection rate (38.6% vs 27.1%, p = 0.003). Using PEG-AA, older age, inadequate bowel preparation (BBPS score < 6) and endoscopy by fellows were found to be factors associated with poor adenoma detection. In the elderly over 65 years of age, a significant difference in cleansing quality between the two groups (7.21 vs 8.19, p < 0.001) was found, but its impact on ADR was not prominent (49.5% vs 45.4%, p = 0.653). CONCLUSIONS: OSTs with simethicone achieved better endoscopic cleanliness, improving adenoma detection rate compared to the conventional PEG-AA protocol. The synergistic effect of both the convenience of taking tablets and the reduction of intraluminal bubble by adjunctive simethicone improves the clinical efficacy of colonoscopy.

Epinephrine injection monotherapy shows similar hemostatic efficacy to epinephrine injection combined therapy in high-risk patients (Forrest Ib) with bleeding ulcers.

BACKGROUND: Whether combination therapy has higher hemostatic efficacy than epinephrine injection monotherapy in different Forrest classifications is not clear. This study aimed to compare hemostatic efficacy between epinephrine injection monotherapy (MT) and combination therapy (CT) based on different Forrest classifications. METHODS: We retrospectively analyzed peptic ulcer bleeding (PUB) patients who underwent endoscopic epinephrine injections or epinephrine injections combined with a second therapy between March 2014 and June 2022 in our center, and the patients were divided into MT group or CT group. Subsequently, a propensity score matching analysis (PSM) was performed and rebleeding rates were calculated according to Forrest classifications via a stratified analysis. RESULTS: Overall, 605 patients who met the inclusion criteria were included, and after PSM, 173 patients in each of the CT and MT groups were included. For PUB patients with nonbleeding visible vessels (FIIa), the rebleeding rates by Days 3, 7, 14, and 30 after PSM were 8.8%, 17.5%, 19.3%, and 19.3% in the MT group, respectively, and rates were 0%, 4.1%, 5.5%, and 5.5% in the CT group, respectively, with significant differences observed between the two groups by Days 3, 7, 14, and 30 (P = 0.015, P = 0.011, P = 0.014, and P = 0.014, respectively). However, for PUB patients with oozing bleeding (FIb), the rebleeding rates by Days 3, 7, 14, and 30 after PSM were 14.9%, 16.2%, 17.6%, and 17.6% in the MT group, respectively, and rates were 13.2%, 14.7%, 14.7%, and 16.2% in the CT group, respectively, with no significant differences observed between the two groups by Days 3, 7, 14, and 30 (P = 0.78, P = 0.804, P = 0.644 and P = 0.825). CONCLUSION: Combined therapy has higher hemostatic efficacy than epinephrine injection monotherapy for PUB patients with visible blood vessel (FIIa) ulcers. However, epinephrine injection monotherapy is equally as effective as combined therapy for PUB patients with oozing blood (FIb) ulcers.

Comparison of placenta consumers' and non-consumers' postpartum depression screening results using EPDS in US community birth settings (n=6038): a propensity score analysis.

BACKGROUND: Preventing postpartum depression (PPD) is the most common self-reported motivation for human maternal placentophagy, yet very little systematic research has assessed mental health following placenta consumption. Our aim was to compare PPD screening scores of placenta consumers and non-consumers in a community birth setting, using propensity score matching to address anticipated extensive confounding. METHODS: We used a medical records-based data set (n = 6038) containing pregnancy, birth, and postpartum information for US women who planned and completed community births. We first compared PPD screening scores as measured by the Edinburgh Postpartum Depression Scale (EPDS) of individuals who consumed their placenta to those who did not, with regard to demographics, pregnancy characteristics, and history of mental health challenges. Matching placentophagic (n = 1876) and non-placentophagic (n = 1876) groups were then created using propensity scores. The propensity score model included more than 90 variables describing medical and obstetric history, demographics, pregnancy characteristics, and intrapartum and postpartum complications, thus addressing confounding by all of these variables. We then used logistic regression to compare placentophagic to non-placentophagic groups based on commonly-cited EPDS cutoff values (≥ 11; ≥ 13) for likely PPD. RESULTS: In the unmatched and unadjusted analysis, placentophagy was associated with an increased risk of PPD. In the matched sample, 9.9% of women who ate their placentas reported EPDS ≥ 11, compared to 8.4% of women who did not (5.5% and 4.8%, respectively, EPDS ≥ 13 or greater). After controlling for over 90 variables (including prior mental health challenges) in the matched and adjusted analysis, placentophagy was associated with an increased risk of PPD between 15 and 20%, depending on the published EPDS cutoff point used. Numerous sensitivity analyses did not alter this general finding. CONCLUSIONS: Placentophagic individuals in our study scored higher on an EPDS screening than carefully matched non-placentophagic controls. Why placentophagic women score higher on the EPDS remains unclear, but we suspect reverse causality plays an important role. Future research could assess psychosocial factors that may motivate some individuals to engage in placentophagy, and that may also indicate greater risk of PPD.

Favorable effect of ripasudil use on surgical outcomes of microhook ab interno trabeculotomy.

PURPOSE: We have previously demonstrated that prolonged use of glaucoma medications was associated with a poor surgical outcome of ab interno trabeculotomy (µTLO). Given that almost all types of glaucoma eye drop either enhance the drainage through the uveoscleral pathway or reduce aqueous humor production, we hypothesized that prolonged use of these medications might cause disuse atrophy of the conventional pathway. In contrast, ripasudil increases the conventional outflow and eventually shows a favorable outcome of µTLO. This study aimed to evaluate the effect of ripasudil use on µTLO outcomes. METHOD: The medical charts of 218 patients who underwent µTLO were analyzed retrospectively. We compared the 1-year outcome between ripasudil users versus nonusers by using propensity score matching. We set the covariates as age, sex, glaucoma types, preoperative intraocular pressure (IOP), the mean deviation values of visual field tests, the presence or absence of concomitant cataract surgery, trabecular meshwork incision range, the presence or absence of any glaucoma medication except ripasudil and duration of glaucoma medical therapy. Success was defined as a postoperative IOP between 5 and 21 mmHg, a ≥ 20% IOP reduction from baseline, and no additional glaucoma surgery at postoperative 1 year. RESULT: Fifty-seven patients each were allocated to the ripasudil users or nonusers. The 1-year success rates were 74% in ripasudil users and 51% in nonusers (p = 0.01). Kaplan‒Meier survival curves also showed that the ripasudil users had a higher survival distribution (p = 0.01). CONCLUSION: The patients who took ripasudil showed a favorable 1-year outcome of µTLO.

Initial treatment approaches and healthcare utilization among veterans with low back pain: a propensity score analysis.

BACKGROUND: Opioid prescriptions for Veterans with low back pain (LBP) persist despite the availability of PT, a lower medical risk treatment option. Patterns of treatment and subsequent healthcare utilization for Veterans with LBP are unknown. The purpose of this study was to evaluate the association of physical therapy (PT) and opioids and outcomes of spinal surgery and chronic opioid use for Veterans with incident LBP. METHODS: We conducted a retrospective cohort study identifying Veterans with a new diagnosis of LBP using ICD codes from the Veterans Administration national database from 2012 to 2017. Veterans were classified into three treatment groups based on the first treatment received within 30 days of incident LBP: receipt of PT, opioids, or neither PT nor opioids. Outcomes, events of spinal surgery and chronic opioid use, were identified beginning on day 31 up to one year following initial treatment. We used propensity score matching to account for the potential selection bias in evaluating the associations between initial treatment and outcomes. RESULTS: There were 373,717 incident cases of LBP between 2012 and 2017. Of those 28,850 (7.7%) received PT, 48,978 (13.1%) received opioids, and 295,889 (79.2%) received neither PT or opioids. Pain, marital status and the presence of cardiovascular, pulmonary, or metabolic chronic conditions had the strongest statistically significant differences between treatment groups. Veterans receiving opioids compared to no treatment had higher odds of having a spinal surgery (2.04, 99% CI: 1.67, 2.49) and progressing to chronic opioid use (11.8, 99% CI: 11.3, 12.3). Compared to Veterans receiving PT those receiving opioids had higher odds (1.69, 99% CI: 1.21, 2.37) of having spinal surgery and progressing to chronic opioid use (17.8, 99% CI: 16.0, 19.9). CONCLUSION: Initiating treatment with opioids compared to PT was associated with higher odds of spinal surgery and chronic opioid use for Veterans with incident LBP. More Veterans received opioids compared to PT as an initial treatment for incident LBP. Our findings can inform rehabilitation care practices for Veterans with incident LBP.

Impact of Malakit intervention on perceptions, knowledge, attitudes, and practices related to malaria among workers in clandestine gold mines in French Guiana: results of multicentric cross-sectional surveys over time.

BACKGROUND: Clandestine gold miners remain key hosts for malaria in French Guiana (FG) and contribute to imported malaria cases in Suriname and Brazil. The Malakit intervention, implemented in FG borders with Suriname and Brazil, provided gold miners with training on malaria and kits for self-diagnosis and self-treatment. Having shown a likely impact on malaria transmission, Suriname has now implemented it in routine care for cross-border moving populations. However, a decrease in malaria transmission is frequently associated with a decrease in risk perception, knowledge, and good practices regarding malaria. This study aims to describe the evolution of the perceptions, knowledge, attitudes, and practices (KAP) related to malaria among clandestine gold miners between 2015 and 2019, and to estimate the impact of Malakit on the FG/Suriname border. METHODS: The primary outcome was the overall KAP score over time and among participants and not participants in the Malakit intervention. A propensity score matching analysis and an inverse probability of treatment weighing analysis were used to estimate the Average Treatment effect on the Treated and the Average Treatment Effect of Malakit, respectively. RESULTS: Perception and knowledge scores were significantly lower in 2019 compared to 2015 (- 0.27 and - 0.23 points, respectively, p < 0.001) while attitude and practice scores were higher (+ 0.16 and + 0.47 points, respectively, p < 0.001). The overall KAP score was significantly higher among participants in Malakit with both propensity score matching (+ 0.72 points, 95%IC [0.29; 1.15]) and inverse probability of treatment weighting analysis (+ 0.70 points, 95%IC [0.34; 1.05]). CONCLUSION: A decrease in perception and knowledge about malaria but an improvement of attitudes and practices as the incidence of malaria decreased are observed. The Malakit intervention seems to have a significant positive impact on the overall KAP related to malaria. The integration of this strategy into malaria control programmes could help to improve the KAP, even in areas where malaria is nearly eliminated, through optimal training and health empowerment. Trial registration ClinicalTrials.gov registration number: NCT03695770.

Association of immunosuppression treatment with generalization among patients with ocular myasthenia gravis: A propensity score analysis.

BACKGROUND: To analyze disease generalization in patients with ocular myasthenia gravis (OMG) treated with immunosuppression compared with patients without immunosuppression treatment. METHODS: In this retrospective cohort study, we analyzed data from patients with OMG at seven medical centers in China from January 1, 2015 to May 1, 2019 and compared disease generalization in patients (treated with immunosuppression vs. not treated) within 2 years of disease onset using raw and inverse probability of treatment weighting (IPTW) analyses. RESULTS: In the study population of 813 patients with OMG, 425 (52.3%) with immunosuppression had a mean (SD) onset age of 50.0 (15.1) years, and 188 (44.2%) were women. The remaining 388 (47.7%) patients were not immunosuppressed (mean age, 48.4 [15.0] years; 185 [47.7%] women). Disease generalization developed in 122 (31.4%) and 37 (8.7%) patients in the non-immunosuppression and immunosuppression groups, respectively. Relative to non-immunosuppression, immunosuppression was associated with a lower risk of generalization in a multivariable-adjusted Cox model (hazard ratio [HR] 0.27; 95% confidence interval [CI] 0.18-0.40; p < 0.001) and IPTW-weighted Cox model (HR 0.28; 95% CI 0.19-0.42; p < 0.001). In sensitivity analyses, longer duration of immunosuppression was associated with a lower risk of generalization (HR 0.90 for every 1-month increase; 95% CI 0.87-0.92; p < 0.001; IPTW-adjusted). Combination therapy with steroids and non-steroidal immunosuppressants showed superior efficacy in reducing the risk of generalization (HR 0.14; 95% CI 0.07-0.26; p < 0.001). CONCLUSION: Immunosuppression significantly reduced the 2-year risk of generalization in patients with OMG.