Effect of Treatment with the PD-1/PD-L1 Inhibitors on Key Health Outcomes of Cancer Patients

BACKGROUND

Recent studies have shown that treatment with the programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) inhibitor class could significantly improve survival outcomes in several oncology indications. However, there is some clinical uncertainty.

OBJECTIVE

This study aimed to obtain high-level estimates of the impact of treatment with PD-1/PD-L1 inhibitor class to oncology treatment on key health outcomes in real-world situations and to inform public health policy decisions about cancer care after reducing uncertainties around new immuno-oncology therapy options in South Korea.

METHODS

A model was developed to estimate the impact of PD-1/PD-L1 inhibitors on outcomes in situations wherein both anti-PD-1/PD-L1s and standard of care (SOC) were available versus SOC only. A partitioned survival model was utilized to estimate the impact of introducing anti-PD-1/PD-L1s on outcomes, including life-years gained, quality-adjusted life-years gained, progression-free survival-years obtained, and grade 3 or higher adverse events avoided for six indications over 5 years. An exponential distribution was fitted to the survival function of the SOC based on visual inspection. Outcomes associated with anti-PD-1/PD-L1s were estimated using a piecewise modeling approach with Kaplan-Meier analysis followed by best-fitting survival analysis. The incident number of patients and market share of anti-PD-1/PD-L1s during 2020-2024 were projected using published literature and Korean market survey data. Sensitivity analyses were performed to test the uncertainty of input parameters.

RESULTS

During the next 5-year period (2020-2024), introducing the anti-PD-1/PD-L1 class led to a gain of 22,001 life-years (+ 31%), 19,073 quality-adjusted life-years (+ 38%), and 22,893 progression-free survival-years (+ 82%); it also avoided 3610 adverse events (- 11%) compared with SOC alone. Most adverse events associated with anti-PD-1/PD-L1s were attributed to combination therapy with cytotoxic chemotherapy (91%). In a scenario wherein the time to reimbursement of the anti-PD-1/PD-L1s was accelerated by 1 year, the life-years gained increased by 14% compared with the base-case scenario.

CONCLUSIONS

Anti-PD-1/PD-L1 therapy is expected to provide marked survival benefits for patients with cancer. This study demonstrated the potentially beneficial health impacts of utilizing the anti-PD-1/PD-L1 class at the population level. The findings could inform health policy decision makers about cancer care and ultimately enhance population health through rapid access to innovative cancer drugs.

Enhanced biofilm formation of Streptococcus gordonii with lipoprotein deficiency

Streptococcus gordonii is a commensal Gram-positive bacterium that acts as an opportunistic pathogen that can cause apical periodontitis, endocarditis, and pneumonia. Biofilm formation of bacteria is important for the initiation and progression of such diseases. Although lipoproteins play key roles in physiological functions, the role of lipoproteins of S. gordonii in its biofilm formation has not been clearly understood. In this study, we investigated the role of lipoproteins of S. gordonii in the bacterial biofilm formation using its lipoprotein-deficient strain (Δlgt). The S. gordonii Δlgt exhibited increased biofilm formation on the human dentin slices or on the polystyrene surfaces compared to the wild-type strain, while its growth rate did not differ from that of the wild-type. In addition, the S. gordonii Δlgt strain exhibited the enhanced LuxS mRNA expression and AI-2 production, which is known to be a positive regulator of biofilm formation, compared to the wild-type. Concordantly, the augmented biofilm formation of S. gordonii Δlgt was attenuated by an AI-2 inhibitor, D-ribose. In addition, lipoproteins from purified S. gordonii inhibited the biofilm formation of S. gordonii wild-type and Δlgt. Taken together, these results suggest that lipoprotein-deficient S. gordonii form biofilms more effectively than the wild-type strain, which might be related to the AI-2 quorum-sensing system.

Health care use and expenditures attributable to cancer: A population-based study

BACKGROUND

As more people are living with cancer due to increases in cancer survival, it is important to understand cancer burden. Studies have examined cancer-related costs using data more than a decade ago.

OBJECTIVE

To update the economic burden and uniquely provide health care service use attributable to cancer using a nationally representative sample of the U.S.

POPULATION

METHODS

Data were obtained from the 2008-2015 Medical Expenditure Panel Survey (MEPS). Individuals with cancer were matched to those without cancer in terms of demographics and comorbidities based on a propensity score (PS). For outcomes of health care use, a (zero-inflated) negative binomial model was employed. To analyze the outcomes of health care spending, a generalized linear model with a log link function and gamma distributed errors (or a two-part model) was used.

RESULTS

Compared to the PS-matched noncancer controls, individuals with cancer received 1.05, 1.08, and 1.76 times more frequent annual emergency department (ED) visit care, hospitalization care, and hospital outpatient visit care, respectively. Additionally, people with cancer received prescriptions and office-based visit care about 5 times and 20 times more frequently. An average annual total health care spending among those with cancer was about $4100 higher. Average annual expenses on hospitalizations, office-based visits, hospital outpatient visits, and prescriptions among those with cancer were also about $1,400, $1,400, $700, and $300 higher. However, there was no significant difference in expenses on ED visit and out-of-pocket expenses on prescriptions between people with cancer and noncancer controls.

CONCLUSIONS

Individuals with cancer used all types of health care services more frequently than noncancer controls. Accordingly, expenditures on various types of health care services among those with cancer were higher.

Optimistic bias and preventive behavioral engagement in the context of COVID-19

Background

The coronavirus (COVID-19) pandemic presents a global crisis. To remain safe, individuals must take preventive measures. Health behavior theories suggest that perceived risk is a key determinant of engagement in preventive behavior. People often underestimate their risk for disease compared with similar others’, a phenomenon known as optimistic bias (OB).

Objective

This study aimed to explore how OB affected individuals' engagement in COVID-19 preventive behavior/intentions. Based on health behavior theories, this study considered risk perception and risk response as mediators of the relationship between OB and individuals’ preventive health behaviors and intentions.

Methods

This study used a cross-sectional survey design. Online survey platforms were used to recruit U.S. adults. A total of 293 valid responses were included in the analyses. Multivariate regression analyses were conducted to determine the relationship of OB to the respondents’ health information seeking intention and related behavioral outcomes.

Results

Results from the first regression model showed that OB was negatively related to risk perception. In other words, optimistically biased respondents perceived their risk of COVID-19 to be low. The second model demonstrated that perceived risk was related positively to affective responses to risk (e.g., worry and fear). That is, the lower their perceived risk of COVID-19, the less likely respondents were to feel anxiety and fear about this disease. Models 3 and 4 revealed positive relationships between risk response and respondents’ intentions and behaviors. Finally, the results supported a fully mediated pathway: OB → risk perception → risk response → information seeking intention and behavioral outcomes.

Conclusions

The study findings suggest that by decreasing their perceived risk and subsequent responses, optimistic bias can undermine individuals’ motivation to take precautions. To reduce this bias, the actual risk of COVID-19 should be reinforced.

Consumer Engagement with Prescription Medicine Decisions: Influences of Health Beliefs and Health Communication Sources

Consumers' prescription drug decisions are affected by a number of structural, psychological, and health communication source variables. To provide a theoretically sound and comprehensive prescription medication decision engagement framework, this study integrated Andersen's Health Service Use Model to address contextual and structural factors, the Health Belief Model (HBM) to examine psychological factors, and extant research on the influence of various health communication sources to explain the prescription drug decision engagement mechanisms of health information-seeking intention, prescription drug-seeking intent, and prescription-seeking behavior. Employing survey methodology, the framework was tested using a sample of U.S. adult consumers (N = 370). Results demonstrated the utility of the integrated model for explaining consumers' participation in their prescription decisions. Specifically, consumers' assessment of target health behaviors and the use of various health communication sources significantly improved the explanatory power of the decision engagement model beyond structural factors. The results impart valuable theoretical contributions and have the potential to guide public health interventions related to consumers' prescription drug decisions.

P10.02 Differentiating microglia and tumour associated macrophages in high grade glioma

BACKGROUND

Glioblastoma multiforme (GBM) is the most common primary brain tumour that affects adults. This aggressive tumour is invariably fatal, carrying a rapid progression and a dismal median survival period of only 15 months despite multimodal treatment approaches. Central to GBM pathogenesis is the immunosuppressive profile of these tumours. The two cell types that are highly abundant in these tumours and play critical roles in the immunosuppressive niche are the brain’s resident microglia and their peripheral counterparts - tumour associated macrophages (TAMs). Despite microglia and TAMs being ontogenetically distinct, these cells have largely been grouped together in research owing to the previous lack of cell-specific markers. Recent evidence has suggested that although TAMs may hold a predominantly pro-tumoral role, microglia may adopt a more anti-tumoral phenotype. Therefore, the differentiation of these two cell types is critical in elucidating the potentially characteristic roles of these two cell types in GBM pathogenesis.

MATERIAL AND METHODS

Tissue sections from resected low- and high-grade glioma tumours, along with epilepsy tissue (control), were used for immunohistochemistry (IHC) staining of macrophage pan-makers (Iba1, CD45, PU.1) and microglial-specific markers (TMEM119, P2RY12). Marker co-localisation was then used to differentiate microglia from TAMs. We further investigated a wider subset of cell-specific markers using multicolour flow cytometry and immunocytochemical staining of isolated cells from patient tissue samples.

RESULTS

Immunofluorescent staining of glioma and epilepsy tissue revealed two clear populations of cells; one population displayed long processes and co-labelling for both pan- and microglial-specific markers, whilst the other population displayed an amoeboid phenotype with only pan-maker staining. Preliminary analysis comparing microglia/TAM populations in low-grade, high-grade and epilepsy tissue suggests a clear difference in the proportions of these cells.

CONCLUSION

Our work complements RNA-Seq studies, showing that TMEM119 and P2RY12, alongside other markers, can indeed identify two distinct myeloid cell populations within glioma tissue. This provides a strong basis for further study where we aim to elucidate the respective roles of microglia and TAMs within tumours. Ultimately, this may hold the potential for differential targeting of these cells using immunotherapies.

Validation of a nomogram to predict the risk of cancer in patients with intraductal papillary mucinous neoplasm and main duct dilatation of 10 mm or less

BACKGROUND

Intraductal papillary mucinous neoplasm (IPMN) is premalignant pancreatic lesion. International guidelines offer limited predictors of individual risk. A nomogram to predict individual IPMN malignancy risk was released, with good diagnostic performance based on a large cohort of Asian patients with IPMN. The present study validated a nomogram to predict malignancy risk and invasiveness of IPMN using both Eastern and Western cohorts.

METHODS

Clinicopathological and radiological data from patients who underwent pancreatic resection for IPMN at four centres each in Eastern and Western countries were collected. After excluding patients with missing data for at least one malignancy predictor in the nomogram (main pancreatic duct diameter, cyst size, presence of mural nodule, serum carcinoembryonic antigen and carbohydrate antigen (CA) 19-9 levels, and age).

RESULTS

In total, data from 393 patients who fit the criteria were analysed, of whom 265 were from Eastern and 128 from Western institutions. Although mean age, sex, log value of serum CA19-9 level, tumour location, main duct diameter, cyst size and presence of mural nodule differed between the Korean/Japanese, Eastern and Western cohorts, rates of malignancy and invasive cancer did not differ significantly. Areas under the receiver operating characteristic (ROC) curve values for the nomogram predicting malignancy were 0·745 for Eastern, 0·856 for Western and 0·776 for combined cohorts; respective values for the nomogram predicting invasiveness were 0·736, 0·891 and 0·788.

CONCLUSIONS

External validation of the nomogram showed good performance in predicting cancer in both Eastern and Western patients with IPMN lesions.

Impacts of the Regional Greenhouse Gas Initiative (RGGI) on infant mortality: a quasi-experimental study in the USA, 2003-2014

OBJECTIVES

The Regional Greenhouse Gas Initiative (RGGI) is the first mandatory market-based regulatory programme to limit regional carbon dioxide (CO₂) emissions in the USA. Empirical evidence has shown that high concentrations of ambient air pollutants such as CO₂ have been positively associated with an increased risk of morbidity (eg, respiratory conditions including asthma and lung cancer) and premature mortality. The purpose of this study was to examine the impacts of RGGI on death rates in infancy.

DESIGN

A quasi-experimental difference-in-differences design.

SETTING AND PARTICIPANTS

We estimated the impacts of RGGI on infant mortality from 2003 through 2014 in the USA (6 years before and after RGGI implementation). Our analytic models included state- and year-fixed effects in addition to a number of covariates.

OUTCOME MEASURES

Death rates in infancy: neonatal mortality rates (NMRs), deaths under 28 days as well as infant mortality rates (IMRs), deaths under 1 year.

RESULTS

Implementation of RGGI was associated with significant decreases in overall NMRs (a reduction of 0.41/1000 live births) and male NMRs (a reduction of 0.43/1000 live births). However, RGGI did not have a significant effect on female NMRs. Similarly, overall IMRs and male IMRs decreased significantly by 0.37/1000 live births and 0.61/1000 live births, respectively, after implementation of RGGI while female IMRs were not significantly affected by RGGI.

CONCLUSIONS

RGGI was associated with decreases in overall infant mortality and boy mortality through reducing air pollutant concentrations. Of note, the impact of this environmental policy on infant girls was much smaller.

Acute and Chronic Effects of Cocaine on Cardiovascular Health

Cardiac complications resulting from cocaine use have been extensively studied because of the complicated pathophysiological mechanisms. This study aims to review the underlying cellular and molecular mechanisms of acute and chronic effects of cocaine on the cardiovascular system with a specific focus on human studies. Studies have consistently reported the acute effects of cocaine on the heart (e.g., electrocardiographic abnormalities, acute hypertension, arrhythmia, and acute myocardial infarction) through multifactorial mechanisms. However, variable results have been reported for the chronic effects of cocaine. Some studies found no association of cocaine use with coronary artery disease (CAD), while others reported its association with subclinical coronary atherosclerosis. These inconsistent findings might be due to the heterogeneity of study subjects with regard to cardiac risk. After cocaine use, populations at high risk for CAD experienced coronary atherosclerosis whereas those at low risk did not experience CAD, suggesting that the chronic effects of cocaine were more likely to be prominent among individuals with higher CAD risk. Studies also suggested that risky behaviors and cardiovascular risks may affect the association between cocaine use and mortality. Our study findings highlight the need for education regarding the deleterious effects of cocaine, and access to interventions for cocaine abusers.

Is Antibiotic Prophylaxis Cost-effective for Dental Patients Following Total Knee Arthroplasty?

Introduction:

Routine antibiotic prophylaxis (AP) to prevent prosthetic joint infection remains controversial. The lack of prophylaxis guideline consensus from the American Academy of Orthopaedic Surgeons (AAOS) and the American Dental Association (ADA) contributes to clinician confusion.

Objectives:

This cost-effectiveness decision model informs the AP debate and guideline development by comparing the benefits, harms, and costs of alternative prophylaxis strategies.

Methods:

A Markov state-transition model was developed comparing lifetime health outcomes and costs of alternative AP strategies for dental patients aged 65 y with a history of total knee arthroplasty (TKA). Based on our interpretation of AP recommendations from the AAOS and ADA, incremental cost-effectiveness ratios were calculated to compare the following strategies: no AP, AP for the first 2 y after a TKA, and lifetime AP.

Results:

The no-AP strategy had the lowest average lifetime costs ($17,119) and quality-adjusted life years (11.2151). Compared with a no-prophylaxis strategy, the 2-y AP strategy had incremental costs of $56 and 0.0006 QALYs gained and was cost-effective (incremental cost-effectiveness ratio = $95,100) when a willingness-to-pay threshold of $100,000 per quality-adjusted life year was used. Based on the results of 1-way sensitivity analysis, the no-AP strategy was cost-effective when we modestly increased base case amoxicillin adverse event estimates that were substantially lower than estimates reported in previous models. When plausible combinations of important model parameters were varied, model results suggested that there may be clinical scenarios when AP may be appropriate for some medically at-risk patient populations.

Conclusion:

The results of cost-effectiveness decision modeling generally support questioning routine AP for dental patients with TKA. Sensitivity analyses suggest that prophylaxis may be cost-effective for patient populations with a higher medical risk of infection. This finding is consistent with the recommendations of the 2015 ADA practice guideline and the appropriate use criteria jointly developed by the AAOS and the ADA.

Knowledge Transfer Statement:

The results of this decision modeling research support the contention that routine AP before invasive dental procedures to prevent prosthetic joint infection may not be cost-effective for patients without medical conditions, potentially conferring a higher infection risk. Model sensitivity analyses suggest that there may be clinical situations when medically at-risk patients benefit from AP.

Health care utilization and expenditures among adults with rheumatoid arthritis using specialty pharmaceuticals

BACKGROUND

Despite the rising popularity of using specialty medications for patients with rheumatoid arthritis (RA), little is known about the use or spending on medical services among these patients.

OBJECTIVE

The objective of this study was to investigate health care utilization and expenditures among patients with RA using specialty medications compared with those using non-specialty (i.e., traditional) medications.

METHODS

This was a retrospective cohort study using Medical Expenditure Panel Survey data from 2009 through 2015. Health care use and expenditures were examined using a (zero-truncated or zero-inflated) negative binomial model and a generalized linear model with a log link function and gamma distribution (or a two-part model).

RESULTS

Compared to patients with RA who were traditional medication users (TMUs), those categorized as specialty medication users (SMUs) were prescribed about 24% fewer medications (incidence rate ratio [IRR] = 0.76, 95% CI = 0.66-0.89) and received fewer office-based visits (IRR = 0.84, 95% CI = 0.70-0.99). Although SMUs' spending on emergency department visits was lower, their spending on total health care was $14,570 higher than that of TMUs. Compared with TMUs, users of both specialty and traditional medications (BMUs) had fewer emergency department visits (IRR = 0.57, 95% CI = 0.39-0.81) with less spending on emergency service use. Overall, BMUs' total health care spending was $5720 higher than TMUs' total spending.

CONCLUSIONS

There were some differences in health care use and expenditures for treating RA between patients using specialty medications and those using traditional medications. Total health care spending was higher for SMUs/BMUs despite their less frequent use of some types of medical services and lower spending on emergency department visits, because of the high cost of specialty medications for RA. The high costs of specialty medications implies the importance of the efficient use of these medications.

Characteristics of patients using specialty medications

BACKGROUND

Specialty medications include innovative drugs and biologic agents requiring special handling and close monitoring. Although specialty medications have been widely used for various chronic conditions, increased use of these medications has contributed a growing share of total health care expenditures.

OBJECTIVE

The aim of this study was to examine patient characteristics related to specialty medication use.

METHODS

Using Medical Expenditure Panel Survey (MEPS) data from 2000 through 2013, this study identified U.S. adults using specialty medications. Andersen's Health Services Utilization model was used to identify potential factors related to specialty medication use. Associations between the variables identified by Andersen's model and specialty medication use were analyzed using logistic multilevel modelling. Sampling weights were considered and standard errors were adjusted to account for the complex survey design.

RESULTS

A fully adjusted model suggested that older adults, individuals with prescription drug insurance, or those using mail order services were more likely to use specialty medications regardless of whether they used traditional medications concurrently. Behaviors of using specialty medications were positively associated with married and active working status and negatively associated with middle or high income and having a usual source of care (visiting a doctor's office, clinic, or health center when sick) when comparing individuals using traditional medications and those using specialty medications. In addition, when comparing individuals using traditional medications with those using both specialty medications and traditional medications, behaviors of using specialty medications were positively associated with female gender, worse health state, and more comorbidities.

CONCLUSION

This study identified characteristics of patients using specialty medications. Some sociodemographic, economic, and clinical factors were related to specialty medication use among U.S. adults.

The Effect of Medicare Part D on Prescription Drug Spending and Health Care Use: 6 Years of Follow-up, 2007-2012

BACKGROUND

Previous studies have shown that Medicare Part D was associated with a reduction in out-of-pocket expenditures for Medicare beneficiaries during the early years of its implementation (2006 and 2007). However, a question remains regarding the effect of Part D on out-of-pocket expenditures in the longer term.

OBJECTIVE

To evaluate the effects of Part D on prescription drug expenditures and certain health care use for a longer time period using a large, nationally representative sample of Medicare beneficiaries.

METHODS

Using Medical Expenditure Panel Survey (MEPS) data from 2000 through 2005 (pre-Part D period) and from 2007 through 2012 (Part D era), this study identified a cohort of elderly Medicare beneficiaries (treatment group) and a near-elderly non-Medicare population (control group). A difference-in-differences analysis was conducted to estimate the effect of Part D on prescription medication use and expenditures and outpatient visits. Propensity score weights and sampling weights were applied to obtain unbiased effect estimates accounting for complex survey designs.

RESULTS

A total of 26,585 elderly Medicare beneficiaries and 20,688 near-elderly non-Medicare beneficiaries were identified. The introduction of Part D was associated with an adjusted average reduction of $105 in annual out-of-pocket spending on prescription drugs during the post-Part D period (2007 through 2012). The reduction in annual out-of-pocket spending ranged from $49 to $152 during the post-Part D period. No significant increase was found in total prescription expenditures or prescription medication use following the introduction of Part D nor were there significant changes in outpatient visits.

CONCLUSIONS

A continued reduction of Part D out-of-pocket drug expenditures was found each year from 2007 to 2012.

DISCLOSURES

No funding has been received to conduct this study or prepare this manuscript. The authors have no conflicts of interest to declare. Study concept and design were primarily contributed by Park with assistance from Jung. Both authors contributed equally to data analysis and interpretation. The manuscript was written primarily by Park, with assistance from Jung, and revised primarily by Jung.

Telephone-adapted Mindfulness-based Stress Reduction (tMBSR) for patients awaiting kidney transplantation

BACKGROUND

Patients with progressive kidney disease experience increasing physiologic and psychosocial stressors and declining health-related quality of life (HRQOL).

METHODS

We conducted a randomized, active-controlled, open-label trial to test whether a Mindfulness-based Stress Reduction (MBSR) program delivered in a novel workshop-teleconference format would reduce symptoms and improve HRQOL in patients awaiting kidney transplantation. Sixty-three transplant candidates were randomized to one of two arms: i) telephone-adapted MBSR (tMBSR, an 8-week program of meditation and yoga); or ii) a telephone-based support group (tSupport). Participants completed self-report questionnaires at baseline, post-intervention, and after 6-months. Anxiety, measured by the State-Trait Anxiety Inventory (STAI) post-intervention served as the primary outcome. Secondary outcomes included: depression, sleep quality, pain, fatigue, and HRQOL assessed by SF-12 Physical and Mental Component Summaries (PCS, MCS).

RESULTS

55 patients (age 54±12yrs) attended their assigned program (tMBSR, n=27; tSupport, n=28). 49% of patients had elevated anxiety at baseline. Changes in anxiety were small and did not differ by treatment group post-intervention or at follow-up. However, tMBSR significantly improved mental HRQOL at follow-up: +6.2 points on the MCS - twice the minimum clinically important difference (95% CI: 1.66 to 10.8, P=0.01). A large percentage of tMBSR participants (≥90%) practiced mindfulness and reported it helpful for stress management.

CONCLUSIONS

Neither mindfulness training nor a support group resulted in clinically meaningful reductions in anxiety. In contrast, finding that tMBSR was more effective than tSupport for bolstering mental HRQOL during the wait for a kidney transplant is encouraging and warrants further investigation. ClinicalTrials.govNCT01254214.