An evaluation of exact matching and propensity score methods as applied in a comparative effectiveness study of inhaled corticosteroids in asthma

Abstract Background Inhaled corticosteroids (ICS) are indicated for prevention of exacerbations in patients with COPD, but they are frequently overprescribed. ICS withdrawal has been recommended by international guidelines in order to prevent side effects in patients in whom ICS are not indicated. Method Observational comparative effectiveness study aimed to evaluate the effect of ICS withdrawal versus continuation of triple therapy (TT) in COPD patients in primary care. Data were obtained from the Optimum Patient Care Research Database (OPCRD) in the UK. Results A total of 1046 patients who withdrew ICS were matched 1:4 by time on TT to 4184 patients who continued with TT. Up to 76.1% of the total population had 0 or 1 exacerbation the previous year. After controlling for confounders, patients who discontinued ICS did not have an increased risk of moderate or severe exacerbations (adjusted HR: 1.04, 95% confidence interval (CI) 0.94–1.15; p = 0.441). However, rates of exacerbations managed in primary care (incidence rate ratio (IRR) 1.33, 95% CI 1.10–1.60; p = 0.003) or in hospital (IRR 1.72, 95% CI 1.03–2.86; p = 0.036) were higher in the cessation group. Unsuccessful ICS withdrawal was significantly and independently associated with more frequent courses of oral corticosteroids the previous year and with a blood eosinophil count ≥ 300 cells/μL. Conclusions In this primary care population of patients with COPD, composed mostly of infrequent exacerbators, discontinuation of ICS from TT was not associated with an increased risk of exacerbation; however, the subgroup of patients with more frequent courses of oral corticosteroids and high blood eosinophil counts should not be withdrawn from ICS. Trial registration European Network of Centres for Pharmacoepidemiology and Pharmacovigilance (EUPAS30851).

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Comparative effectiveness study of chemotherapy in follicular lymphoma patients in the rituximab era: a Japanese claims database study

Future Oncology ◽

10.2217/fon-2020-0832 ◽

2020 ◽

Author(s):

Saaya Tsutsué ◽

Kensei Tobinai ◽

Jingbo Yi ◽

Bruce Crawford

Keyword(s):

Length Of Stay ◽

Propensity Score ◽

Follicular Lymphoma ◽

Clinical Outcomes ◽

Comparative Effectiveness ◽

Clinical Characteristics ◽

First Year ◽

Effectiveness Study ◽

Claims Database ◽

Comparative Effectiveness Study

Aim: To evaluate comparative effectiveness of rituximub (R)-based versus non-R-based therapies for follicular lymphoma patients in Japan, where limited studies have been reported. Materials & methods: Patients who received R-based index regimens were propensity score matched to those who did not receive R, based on patient baseline attributes and clinical characteristics using Japanese retrospective claims database to assess clinical and economic outcomes. Results & conclusion: A total of 1947 patients remained in the overall follicular lymphoma cohorts: 1294 receiving an R-based and 653 a non-R-based regimen. Patients on R-based therapy underwent fewer hospitalizations and had a shorter length of stay, but had higher costs during the first year of intensive R-based therapy. Improved clinical outcomes were associated with patients who were younger, female and chose R-based regimens in first index line.

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Utility of Automated Data-adaptive Propensity Score Method for Confounding by Indication in Comparative Effectiveness Study in Real World Medicare and Registry Data

10.1101/2021.04.06.21254887 ◽

2021 ◽

Author(s):

Hiraku Kumamaru ◽

Jessica J Jalbert ◽

Louis L Nguyen ◽

Lauren A Williams ◽

Hiroaki Miyata ◽

...

Keyword(s):

Propensity Score ◽

Real World ◽

Comparative Effectiveness ◽

Registry Data ◽

Effectiveness Study ◽

Confounding By Indication ◽

Surgical Risk ◽

High Surgical Risk ◽

Comparative Effectiveness Study ◽

Data Adaptive

Background: Confounding by indication is a serious threat to comparative studies using real world data. We assessed the utility of automated data-adaptive analytic approach for confounding adjustment when both claims and clinical registry data are available. Methods: We used a comparative study example of carotid artery stenting (CAS) vs. carotid endarterectomy (CEA) in 2005-2008 when CAS was only indicated for patients with high surgical risk. We included Medicare beneficiaries linked to the Society for Vascular Surgery's Vascular Registry >65 years old undergoing CAS/CEA. We compared hazard ratios (HRs) for death while adjusting for confounding by combining various 1) Propensity score (PS) modeling strategies (investigator-specified [IS-PS] vs. automated data-adaptive [ada-PS]); 2) data sources (claims-only, registry-only and claims-plus-registry); and 3) PS adjustment approaches (matching vs. quintiles-adjustment with/without trimming). An HR of 1.0 was a benchmark effect estimate based on CREST trial. Results: The cohort included 1,999 CAS and 3,255 CEA patients (mean age 76). CAS patients were more likely symptomatic and at high surgical risk, and experienced higher mortality (crude HR=1.82 for CAS vs. CEA). HRs from PS-quintile adjustment without trimming were 1.48 and 1.52 for claims-only IS-PS and ada-PS, 1.51 and 1.42 for registry-only IS-PS and ada-PS, and 1.34 and 1.23 for claims-plus-registry IS-PS and ada-PS, respectively. Estimates from other PS adjustment approaches showed similar patterns. Conclusions: In a comparative effectiveness study of CAS vs. CEA with severe confounding by indication, ada-PS performed better than IS-PS in general, but both claims and registry data were needed to adequately control for bias.

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