COVID-19 pandemic and trends in clinical outcomes and medication use for patients with established atrial fibrillation: A nationwide analysis of claims data

Study objective

The COVID-19 pandemic disrupted multiple aspects of the health care system, including the diagnosis and control of chronic conditions. This study aimed to quantify pandemic-related changes in the rates of clinical events among patients with atrial fibrillation (AF).

Design/setting/participants

In this retrospective cohort study, we identified individuals with established AF at any time before 2019 using de-identified Optum's Clinformatics® Data Mart, and followed them from 3/18/2019 to death, or disenrollment, or the end of the study (09/30/2021).

Main outcome

Rates of clinical event, including all-cause hospitalization, ischemic stroke, and bleeding. We constructed interrupted time series to test changes in outcomes after the onset of the COVID-19 pandemic (3/11/2020, date of pandemic declaration). We then identified the first month after the start of the pandemic in which outcomes returned to pre-pandemic levels.

Results

A total of 561,758 patients, with a mean age of 77 ± 9.9 years, were included in the study. The monthly incidence rate of all-cause hospitalization decreased from 2.8 % in the period immediately before the pandemic declaration to 1.7 % in the period immediately after, with p-value for level change<0.001. The rate of new ischemic stroke diagnoses decreased from 0.28 % in the period immediately before pandemic declaration to 0.20 % in the period immediately after, and the rate of major bleeding diagnoses from 0.81 % to 0.59 %, both p-values for level change<0.01. The incidence rate of ischemic stroke and bleeding events returned to pre-pandemic levels in October and November 2020, respectively.

Conclusions

The COVID-19 pandemic was associated with a decrease in health care visits for ischemic stroke and bleeding in a nationwide cohort of patients with established AF.

Medicare drug price negotiation: The complexities of selecting therapeutic alternatives for estimating comparative effectiveness

Under the 2022 Inflation Reduction Act, the Centers for Medicare and Medicaid Services (CMS) are able to negotiate prices for topselling drugs in the Medicare Part B and D programs. In determining initial price offers, CMS will compare the prices and clinical benefits of the drugs subject to negotiation to the prices and clinical benefits of therapeutic alternatives. Despite the central role that the selection of therapeutic alternatives will play in the price negotiations, the available guidance published by CMS provides few details about how the organization will undertake this process, which will be particularly complex for drugs approved for more than one indication. To better inform the selection process, we identified all US Food and Drug Administration-approved indications for the first 10 drugs subject to negotiation. Using 2020-2021 Medicare claims data, we identified Medicare Part D beneficiaries using each of the 10 drugs. We extracted medical claims with diagnosis codes for each of the approved indications to report the relative treated prevalence of use by indication for each drug. We reviewed published clinical guidelines to identify relevant therapeutic alternatives for each of the indications. We integrated the evidence on the relative treated prevalence of indications and clinical guidelines to propose therapeutic alternatives for each of the 10 drugs. We describe challenges that CMS may face in selecting therapeutic alternatives.

Reimbursement to Pharmacies for Generic Drugs by Medicare Part D Sponsors

This study evaluates whether organizations that offer Medicare Part D plans (referred to as Part D sponsors) overpay pharmacies for generic drugs.

COVID-19 pandemic and initiation of treatment for atrial fibrillation: a nationwide analysis of claims data

BACKGROUND

The COVID-19 pandemic profoundly disrupted the delivery of medical care. It remains unclear whether individuals diagnosed with new onset disease during the pandemic were less likely to initiate treatments after diagnosis. We sought to evaluate changes in the treatment initiation of patients newly diagnosed with atrial fibrillation (AF) after the onset of the COVID-19 pandemic.

METHODS

In this retrospective cohort study, we identified individuals with incident AF from 01/01/2016-09/30/2021 using Optum's de-identified Clinformatics® Data Mart Database. The primary outcome was initiation of oral anticoagulation (OAC) within 30 days of AF diagnosis. Secondary outcomes included initiation of OAC within 180 days of diagnosis, initiation of warfarin, direct oral anticoagulants (DOACs), rhythm control medications and electrical cardioversion within 30 days of diagnosis. We constructed interrupted time series analyses to examine changes in the outcomes following the onset of the pandemic.

RESULTS

A total of 573,524 patients (age 73.0 ± 10.9 years) were included in the study. There were no significant changes in the initiation of OAC, DOAC, and rhythm control medications associated with the onset of the pandemic. There was a significant decrease in initiation of electrical cardioversion associated with the onset of the pandemic. The rate of electronic cardioversion within 30 days of diagnosis decreased by 4.9% per 1,000 patients after the onset of the pandemic and decreased by about 35% in April 2020, compared to April 2019, from 5.53% to 3.58%.

CONCLUSION

The COVID-19 pandemic did not affect the OAC initiation within 30 days of AF diagnosis but was associated with a decline in the provision of procedures for patients newly diagnosed with AF.

Trends in Proportion of Medicare Part D Claims Subject to 340B Discounts, 2013-2020

Importance

Despite controversy surrounding the 340B program, no study has analyzed trends in the proportion of Medicare Part D pharmacy claims eligible for 340B discounts.

Objective

To describe trends in the proportion of Medicare Part D claims that are prescribed by 340B-affiliated clinicians and filled in 340B pharmacies.

Design and Setting

This longitudinal, retrospective cohort study included 2013 to 2020 claims data from a 5% random sample of Medicare Part D beneficiaries from the Centers for Medicare & Medicaid Services and 6292 nine-digit national drug codes that were used by at least 1000 Part D beneficiaries in a given year. Data analysis was completed from November 2022 to April 2023.

Main Outcomes and Measures

For each drug and year, there were 3 outcomes: (1) proportion of total Part D claims that were prescribed by a 340B-affiliated clinician; (2) proportion of claims prescribed by a 340B-affiliated clinician that were filled in a 340B pharmacy; and (3) proportion of total Part D claims under the 340B program (ie, prescribed by a 340B-affiliated clinician and filled in a 340B pharmacy).

Results

The proportion of prescriptions written by a 340B-affiliated clinician doubled from 9.4% in 2013 to 19.3% in 2020. The capture of 340B prescriptions by 340B pharmacies, defined as the proportion of claims prescribed by 340B-affiliated clinicians that were filled by 340B pharmacies, increased from 18.4% in 2013 to 49.9% in 2020. As a result, the total proportion of 340B claims in Part D increased from 1.7% in 2013 to 9.6% in 2020. Rates of 340B prescribing and capture increased consistently across therapeutic classes. In 2020, the antiviral therapeutic class was the class with the largest proportion of 340B claims (16.1%), followed by targeted antineoplastics (15.7%).

Conclusions and Relevance

This cohort study demonstrated that from 2013 to 2020, the share of Medicare Part D claims prescribed by a 340B-affiliated clinician increased; however, the rate at which 340B-eligible prescriptions were filled at 340B pharmacies increased at a faster rate, driving the overall increase in 340B claims. Despite these trends, only half of 340B-eligible prescriptions were subject to the 340B discount in 2020.

Nonfederal average manufacturer price to estimate savings generated by minimum discounts under the Inflation Reduction Act

DISCLOSURES: This work was funded by the West Health Policy Center. Dr Hernandez reports consulting fees from Pfizer and BMS, outside of the submitted work. Following the submission of the original manuscript, Dr Dickson became an employee of AHIP. AHIP has had no role in reviewing this letter. The statements, findings, conclusions, views, and opinions contained and expressed herein are not necessarily those of IQVIA Inc. or any of its affiliated or subsidiary entities.

Individual and social determinants of adherence to sodium-glucose cotransporter 2 inhibitor therapy: A trajectory analysis

BACKGROUND: Sodium-glucose cotransporter 2 inhibitors (SGLT2is) are known to improve cardiovascular and renal outcomes in patients with type 2 diabetes (T2D). Understanding the longitudinal patterns of adherence and the associated predictors is critical to addressing the suboptimal use of this outcome-improving treatment. OBJECTIVE: To characterize the distinct trajectories of adherence to SGLT2is in patients with T2D and to identify patient characteristics and social determinants of health (SDOHs) associated with SGLT2i adherence. METHODS: In this retrospective cohort study, we identified patients with T2D who initiated and filled at least 1 SGLT2i prescription according to 2012-2016 national Medicare claims data. The monthly proportion of days covered with SGLT2is for each patient was incorporated into group-based trajectory models to identify groups with similar adherence patterns. A multinomial logistic regression model was constructed to examine the association between patient characteristics and group membership. In addition, the association between context-specific SDOHs (eg, neighborhood median income and neighborhood employment rate) and adherence to an SGLT2i regimen was explored in both the overall cohort and the racial and ethnic subgroups. RESULTS: The final sample comprised 6,719 patients with T2D. Four trajectories of SGLT2i adherence were identified: continuously adherent users (49.6%), early discontinuers (27.5%), late discontinuers (14.5%), and intermediately adherent users (8.4%). Patient age, sex, race, diabetes duration, and Medicaid eligibility were significantly associated with trajectory group membership. Areas with a higher unemployment rate, lower income level, lower high school education rate, worse nutrition environment, fewer health care facilities, and greater Area Deprivation Index scores were found to be associated with low adherence to SGLT2is. CONCLUSIONS: Four distinct trajectories of adherence to SGLT2is were identified, with only half of the patients remaining continuously adherent to their treatment regimen during the first year after initiation. Several contextual SDOHs were associated with suboptimal adherence to SGLT2is.

HPV Infection Causes Dependence on Alternative DNA Damage Response Pathways Providing Cancer Specific Targets for Radiosensitization

PURPOSE/OBJECTIVE(S)

Cancer-specific radiosensitization is an attractive approach to improving the efficacy of radiotherapy. However, drugs targeting ubiquitous DNA damage response pathways are not cancer specific and can increase radiation related side effects. Thus, there is an unmet need for tumor specific molecular targets. This approach requires an identification of DNA damage signaling pathways that are unique to cancer cells. We hypothesized that by expressing its genome in the host cells HPV infection can rewire DNA damage signaling making HPV-positive tumor cells dependent on alternative pathways to survive radiation, which can be exploited for radiosensitization of HPV-induced cancers.

MATERIALS/METHODS

We have performed a CRISPR/Cas9 screen in HPV-positive SiHa cells that either express HPV16 proteins E6 and E7 or contain a selective knock-out of E6 or E7. We used next-generation sequencing to determine the abundance of gRNA in cells that were mock-treated or irradiated. We identified genes that were required for survival of radiation specifically in the context of E6 or E7 expression. Results of the screen were validated by generating knock-outs of the discovered genes using CRISPR/Cas9. By applying an array of molecular tools to analyze cell survival, cell cycle progression and mitotic progression we assessed the role of these genes in radiation response in HPV-positive cancer cells.

RESULTS

We have identified genes that are required for survival of radiation-induced DNA damage in the context of either E6 or E7 expression. We demonstrate that targeting these genes results in hypersensitization of cervical cancer cells to radiation specifically in the presence of E6 or E7. We show that the gene product required for survival in E6-expressing cells is critical for mitotic progression after radiation exposure serving as a member of a protein complex stabilizing the attachment of mitotic spindle to centromeres.

CONCLUSION

We have uncovered specific genes that are critical for DNA damage response and cell survival after radiation exposure in HPV-positive cells. Our findings suggest that expression of the HPV proteins E6 and E7 rewires DNA damage signaling causing dependence on alternative response pathways. We propose that these pathways can be targeted for a tumor-specific radiosensitization of HPV-induced cancers.

Association Between Redlining and Spatial Access to Pharmacies

This cross-sectional study evaluates whether there is an association between historic redlining and living within 1 or 2 miles of a pharmacy.

Changes In Net Prices And Spending For Pharmaceuticals After The Introduction Of New Therapeutic Competition, 2011-19

Previous research has demonstrated that the introduction of a new brand-name pharmaceutical competitor does not lower list prices for existing competitive therapies. However, no study has systematically evaluated the impact of new therapeutic competition on net prices of pharmaceutical products. We identified new therapies approved during the period 2013-17 that were competitors for existing treatments. We used a novel peer-reviewed algorithm to estimate the net prices of existing therapies. We implemented regression models to estimate changes in these net prices after the approval of the new therapeutic competition during the period 2011-19. Across twelve therapeutic classes with new drug entrants in 2013-17, the introduction of new therapeutic competition was associated with a 4.2 percent decrease in annual net price growth. The introduction of new brand-name therapies in twelve therapeutic classes reduced net commercial spending on existing therapies by $10.4 billion-an 18.5 percent reduction in projected spending absent therapeutic competition. Our findings demonstrate that new therapeutic competition allows pharmacy benefit managers to use formulary management to decrease net prices and reduce drug spending, contrary to observed trends in list price increases.

Estimated discounts generated by Medicare drug negotiation in 2026

BACKGROUND: Starting in 2026, Medicare will be able to negotiate drug prices. Although recent reports have identified the drugs that will likely face negotiation, no study has estimated the maximum negotiated price according to guidance from the Centers for Medicare and Medicaid Services. OBJECTIVE: To identify the maximum negotiated price for the 10 drugs expected to be negotiated by Medicare in 2026. METHODS: We apply peer-reviewed methodology to estimate 2020 rebates for the 10 drugs anticipated to be negotiated by Medicare in 2026. We compare rebates to the statutory minimum discounts to identify the maximum negotiated price in 2026 and estimate savings. RESULTS: The minimum discount stipulated by the Inflation Reduction Act exceeds 2020 rebates for 4 of the 10 drugs expected to be negotiated in 2026, including etanercept, which is subject to a minimum discount of 60%, compared with an estimated rebate of 39.1%, and the cancer drugs ibrutinib, palbociclib, and enzalutamide, all of which will be subject to a minimum discount of 25%, compared with estimated rebates of 9%, 5.7% and 15.0%, respectively. Based on 2020 gross spending, the minimum required discount on these 4 drugs would generate savings of $1.8 billion. CONCLUSIONS: In 2026, minimum discounts will only apply to 4 of 10 drugs likely subject to negotiation. For most drugs, net prices will establish the ceiling for the negotiated price. To achieve the savings projected by the Congressional Budget Office ($3.7 billion), negotiated prices will have to fall below the ceiling for the negotiated price established by the statute. DISCLOSURES: This work was funded by the West Health Policy Center. Dr Hernandez reports consulting fees from Pfizer and Bristol Meyers Squibb, outside of the submitted work. Following the submission of this manuscript, Mr Dickson became an employee of American's Health Insurance Plans. American's Health Insurance Plans had no role in reviewing this manuscript. The statements, findings, conclusions, views, and opinions contained and expressed herein are not necessarily those of IQVIA Inc. or any of its affiliated or subsidiary entities.

Role of independent versus chain pharmacies in providing pharmacy access: a nationwide, individual-level geographic information systems analysis

Pharmacy accessibility is critical for equity in medication access and is jeopardized by pharmacy closures, which disproportionately affect independent pharmacies. We conducted a geographic information systems analysis to quantify how many individuals across the US do not have optimal pharmacy access or solely rely on independent pharmacies for access. We generated service areas of pharmacies using OpenStreetMap data. For each individual in a 30% random sample of the 2020 RTI US Household Synthetic Population™ (n=90,778,132), we defined optimal pharmacy access as having a driving distance to the closest pharmacy ≤2 miles in urban counties, ≤5 miles in suburban counties, and ≤10 miles in rural counties. Individuals were then categorized according to their access to chain and independent pharmacies. Five percent of the sample or ~15.1 million individuals nationwide relied on independent pharmacies for optimal access. Individuals relying on independent pharmacies for optimal access were more likely to live in rural areas, be 65 years or older, and belong to low-income households. Another 19.5% of individuals in the sample did not have optimal pharmacy access, which corresponds to 59.0 million individuals nationwide. Our findings demonstrate that independent pharmacies play a critical role in ensuring equity in pharmacy access.

Variation in Statewide Intravesical Treatment Rates for Non-Muscle Invasive Bladder Cancer During the Bacillus Calmette-Guerin Drug Shortage

OBJECTIVE

To measure the changes in treatment patterns for non-muscle invasive bladder cancer before and during the Bacillus Calmette-Guerin (BCG) drug shortage.

MATERIALS AND METHODS

We used a 5% random sample of Medicare beneficiaries and identified 7971 bladder cancer patients (2648 pre-BCG shortage and 5323 during the shortage) ≥66 years of age who received intravesical treatment within 1 year of diagnosis between 2010 and 2017. The BCG shortage period was defined from July 2012 ongoing. Full induction treatment with BCG, mitomycin C, gemcitabine, or other intravesical agents was defined as receiving ≥5 of 6 treatments within 60 days. State-level BCG use before and during the drug shortage was compared in US states reporting at least 50 patients in each period. Independent variables included year of index date, age, sex, race, rurality, and region of residence.

RESULTS

BCG utilization rates decreased 5.9% in the shortage period (95% CI (-8.2%)-(-3.7%)). The proportion of patients that completed a full induction course of BCG decreased from 31.0% in the pre-shortage period to 27.6% in the shortage period (P = .002). 84% of reporting states (16 of 19) had decreased BCG utilization ranging between 5% and 36% compared to pre-shortage rates.

CONCLUSION

During the BCG drug shortage, eligible bladder cancer patients were less likely to receive gold standard intravesical BCG with a large variation in treatment patterns between US states.

Estimated Changes in Insulin Prices and Discounts After Entry of New Insulin Products, 2012-2019

Importance

Despite the political salience of insulin prices, no study to date has quantified trends in insulin prices that account for manufacturer discounts (net prices).

Objective

To describe trends in insulin list prices and net prices faced by payers from 2012 to 2019 and estimate changes in net prices after the 2015 to 2017 entry of new insulin products.

Design, Setting, and Participants

This longitudinal study included an analysis of Medicare, Medicaid, and SSR Health drug pricing data from January 1, 2012, to December 31, 2019. Data analyses were performed from June 1, 2022, to October 31, 2022.

Exposures

US sales of insulin products.

Main Outcomes and Measures

Net prices faced by payers were estimated for insulin products as list prices minus manufacturer discounts negotiated in commercial and Medicare Part D markets (ie, commercial discounts). Trends in net prices were evaluated before and after the entry of new insulin products.

Results

Net prices of long-acting insulin products increased at an annual rate of 23.6% from 2012 to 2014 but decreased at an annual rate of 8.3% after the introduction of insulin glargine (Toujeo and Basaglar) and degludec (Tresiba) in 2015. Net prices of short-acting insulin increased at an annual rate of 5.6% from 2012 to 2017 but then decreased from 2018 to 2019 after the introduction of insulin aspart (Fiasp) and lispro (Admelog). For human insulin products, which did not experience entry of new products, net prices increased at an annual rate of 9.2% from 2012 to 2019. From 2012 to 2019, commercial discounts increased from 22.7% to 64.8% for long-acting insulin products, from 37.9% to 66.1% for short-acting insulin products, and from 54.9% to 63.1% for human insulin products.

Conclusions and Relevance

In this longitudinal study of US insulin products, results suggest that insulin prices substantially increased from 2012 to 2015, even after accounting for discounts. The introduction of new insulin products was followed by substantial discounting practices that lowered net prices faced by payers.

Assessment of Commercial and Mandatory Discounts in the Gross-to-Net Bubble for the Top Insulin Products From 2012 to 2019

Importance

Insulin list prices have grown substantially since 2010, but net prices have declined since 2015 because of manufacturer discounts, leading to an increasingly large difference between list and net prices of drugs often called the gross-to-net bubble. It remains unclear to what extent the gross-to-net bubble represents voluntary manufacturer discounts negotiated in commercial and Medicare Part D markets (hereafter called commercial discounts) vs mandatory discounts under the Medicare Part D coverage gap, Medicaid, and the 340B program.

Objective

To decompose the overall gross-to-net bubble of leading insulin products into discount types.

Design, Setting, and Participants

This economic evaluation obtained data from Medicare and Medicaid claims and spending dashboards, Medicare Part D Prescriber Public Use File, and SSR Health for the top 4 commonly used insulin products: Lantus, Levemir, Humalog, and Novolog. The gross-to-net bubble, which represents total discounts, was estimated for each insulin product and year (from 2012 to 2019). Analyses were conducted in June to December 2022.

Main Outcomes and Measures

The gross-to-net bubble was decomposed into 4 discount types: (1) Medicare Part D coverage gap discounts, (2) Medicaid discounts, (3) 340B discounts, and (4) commercial discounts. Coverage gap discounts were estimated using Medicare Part D claims data. Medicaid and 340B discounts were estimated using a novel algorithm that accounted for best prices set by commercial discounts.

Results

Total discounts for the 4 insulin products increased from $4.9 billion to $22.0 billion. Commercial discounts represented a majority of all discounts, increasing from 71.7% of the gross-to-net bubble in 2012 ($3.5 billion) to 74.3% ($16.4 billion) in 2019. Among mandatory discounts, coverage gap discounts remained relatively consistent as a proportion of discounts (5.4% in 2012 vs 5.3% in 2019). Medicaid rebates decreased as a proportion of total discounts, from 19.7% in 2012 to 10.6% in 2019. The 340B discounts increased as a proportion of total discounts from 3.3% in 2012 to 9.8% in 2019. Results for the contribution of discount types to the gross-to-net bubble were consistent across insulin products.

Conclusions and Relevance

Results of a decomposition of the gross-to-net bubble for leading insulin products suggest that commercial discounts play a growing role in lowering net sales compared with mandatory discounts.

Abstract P541: Trends in Initiation of Anticoagulation for Atrial Fibrillation in the Early Months of the COVID-19 Pandemic

Introduction: Oral anticoagulation (OAC) is the treatment of choice to prevent stroke in patients with atrial fibrillation (AF). We evaluated changes in OAC initiation in newly diagnosed AF after the onset of the COVID-19 pandemic.

Hypothesis: We hypothesized that individuals newly diagnosed with AF in the early months of the COVID-19 pandemic would be less likely to initiate OAC than those with incident AF before the pandemic.

Methods: We selected individuals with incident AF in 01/01/2016 - 09/30/2021 from Optum’s de-identified Clinformatics® Data Mart Database. AF was defined by having ICD-9 code 427.31 or ICD-10 codes I48.0, I48.1, I48.2, or I48.91 at the first or second diagnosis field. For every 30-day period. We measured the proportion of individuals newly diagnosed with AF initiated OAC within 30 or 180 days of diagnosis. As secondary outcomes, we evaluated the initiation of warfarin and of direct oral anticoagulants (DOACs) individually. We constructed interrupted time series analyses to examine changes in the level and trend of OAC initiation following the onset of the COVID-19 pandemic, defined by the date of the World Health Organization declaration (3/11/2020).

Results: The study sample included 573,524 individuals (age 73± 11 years, 48% female sex, 85% Medicare beneficiaries). Although initiation of OAC and DOAC increased in 01/01/2016-09/30/2021 (Figure), there were no significant changes associated with the onset of pandemic (all P>0.05). Rates of warfarin initiation decreased over time, from 9.7% in year 2016 to 1.9% in year 2021.

Conclusion: There were no significant changes in the initiation of OAC immediately after the onset of the COVID-19 pandemic among patients newly diagnosed with AF during this time.

COVID-19 pandemic and trends in new diagnosis of atrial fibrillation: A nationwide analysis of claims data

BACKGROUND

Atrial fibrillation (AF) is associated with a five-fold increased risk of stroke and a two-fold increased risk of death. We aimed to quantify changes in new diagnoses of AF following the onset of the COVID-19 pandemic. Investigating changes in new diagnoses of AF is of relevance because delayed diagnosis interferes with timely treatment to prevent stroke, heart failure, and death.

METHODS

Using De-identified Optum's Clinformatics® Data Mart, we identified 19,500,401 beneficiaries continuously enrolled for 12 months in 2016-Q3 2020 with no history of AF. The primary outcome was new AF diagnoses per 30-day interval. Secondary outcomes included AF diagnosis in the inpatient setting, AF diagnosis in the outpatient setting, and ischemic stroke as initial manifestation of AF. We constructed seasonal autoregressive integrated moving average models to quantify changes in new AF diagnoses after the onset of the COVID-19 pandemic (3/11/2020, date of pandemic declaration). We tested whether changes in the new AF diagnoses differed by race and ethnicity.

RESULTS

The average age of study participants was 51.0±18.5 years, and 52% of the sample was female. During the study period, 2.7% of the study sample had newly-diagnosed AF. New AF diagnoses decreased by 35% (95% CI, 21%-48%) after the onset of the COVID-19 pandemic, from 1.14 per 1000 individuals (95% CI, 1.05-1.24) to 0.74 per 1000 (95% CI, 0.64 to 0.83, p-value<0.001). New AF diagnoses decreased by 37% (95% CI, 13%- 55%) in the outpatient setting and by 29% (95% CI, 14%-43%) in the inpatient setting. The decrease in new AF diagnoses was similar across racial and ethnic subgroups.

CONCLUSION

In a nationwide cohort of 19.5 million individuals, new diagnoses of AF decreased substantially following the onset of the COVID-19 pandemic. Our findings evidence pandemic disruptions in access to care for AF, which are concerning because delayed diagnosis interferes with timely treatment to prevent complications.

Association of New Use of Antihypertensives That Stimulate vs Inhibit Type 2 and 4 Angiotensin II Receptors With Dementia Among Medicare Beneficiaries

Importance

Prevalent use of antihypertensive medications that stimulate type 2 and 4 angiotensin II receptors, compared with those that do not stimulate these receptors, has been associated with a lower risk of dementia. However, previous studies were limited by inclusion of individuals with prevalent hypertension and a history of antihypertensive use prior to the start of the study, which can introduce bias.

Objective

To examine the association of new use of antihypertensive medication regimens that stimulate vs inhibit type 2 and 4 angiotensin II receptors with Alzheimer disease and related dementias (ADRD) among Medicare beneficiaries.

Design, Setting, and Participants

This cohort study was conducted among 57 773 Medicare fee-for-service beneficiaries (January 1, 2006, through December 31, 2018) aged 65 years or older with incident hypertension. Data analysis was conducted from January 1 through June 30, 2022.

Exposures

Initiation of antihypertensive medication regimens that stimulate or inhibit type 2 and 4 angiotensin II receptors, or mixed regimens (both stimulating and inhibiting), with the time-dependent measure being each 30-day interval.

Main Outcomes and Measures

The primary outcome was time to first occurrence of ADRD (Centers for Medicare & Medicaid Services Chronic Conditions Data Warehouse definition). Cox proportional hazards regression modeling with time-dependent variables was performed to estimate the association between time-dependent treatment groups and time to ADRD, after adjusting for sociodemographic and clinical characteristics.

Results

The sample included 57 773 Medicare beneficiaries (36 348 women [62.9%]; mean [SD] age, 73.8 [6.3] years; 2954 [5.1%] Black, 1545 [2.7%] Hispanic; 50 184 [86.9%] White, and 3090 [5.4%] Other individuals [the Other category included individuals of American Indian, Asian, other, or unknown race and ethnicity]). During a median of 6.9 years (IQR, 4.7-9.3 years) of follow-up, the unadjusted incidence density rate of ADRD was 2.2 cases per 100 person-years (95% CI, 2.1-2.4 cases per 100 person-years) for the group receiving regimens that stimulate type 2 and 4 angiotensin II receptors compared with 3.1 cases per 100 person-years (95% CI, 3.0-3.2 cases per 100 person-years) for the group receiving regimens that inhibit type 2 and 4 angiotensin II receptors and 2.7 cases per 100 person-years (95% CI, 2.6-2.9 cases per 100 person-years) for the group receiving mixed treatment regimens. In adjusted Cox proportional hazards regression modeling, stimulating treatment was associated with a statistically significant 16% reduction in the hazard of ADRD compared with inhibiting treatment (hazard ratio, 0.84; 95% CI, 0.79-0.90). Mixed regimen use was also associated with reduced hazards of ADRD compared with the inhibiting group (hazard ratio, 0.90; 95% CI, 0.84-0.96).

Conclusions and Relevance

This cohort study of Medicare beneficiaries suggests that use of antihypertensive medications that stimulate type 2 and 4 angiotensin II receptors was associated with lower risk of ADRD compared with antihypertensive medications that inhibit these receptors. Confirmation is needed in a randomized trial.

Reduction in Medicaid Rebates Paid by Pharmaceutical Manufacturers for Outpatient Infused, Injected, Implanted, Inhaled, or Instilled Drugs: The 5i Loophole

CONTEXT

When nonretail pharmacy sales exceed 70% of sales, manufacturers of infused, injected, implanted, inhaled, or instilled (5i) drugs are required to calculate average manufacturer price (AMP) under a different methodology than that used for drugs predominantly distributed through retail channels. Specifically, the modified methodology includes pharmacy benefit manager (PBM) rebates in the calculation of AMP for 5i drugs. The modified methodology reduces manufacturers' Medicaid rebate liability and increases net costs to the Medicaid program.

METHODS

The authors identified 15 5i drugs predominantly dispensed through the nonretail setting. Using 2013-2017 data from Medicaid, Medicare, SSR Health, and 340B program eligibility, they estimated differences in AMP, Medicaid rebates, and net Medicaid costs under both the standard and 5i AMP methodologies.

FINDINGS

AMP was 42% lower, on average, under the 5i methodology than under the standard methodology. From 2013-2017, Medicaid rebates under the 5i methodology were 82% lower than under the standard methodology, resulting in manufacturers of these 15 drugs reducing their Medicaid rebate liability by $1.1 billion in five years.

CONCLUSIONS

Inclusion of PBM rebates in the calculation of AMP for 5i drugs significantly reduced Medicaid rebates, resulting in higher Medicaid spending. This may incentivize manufacturers to shift sales to nonretail channels. To remove this incentive, policy makers should consider excluding PBM rebates from the calculation of AMP for 5i drugs.

Estimated changes in price discounts for tenofovir-inclusive HIV treatments following introduction of tenofovir alafenamide

We estimated list and net prices for tenofovir disoproxil fumarate (TDF) products Truvada, Complera, and Stribild, and their tenofovir alafenamide (TAF) versions Descovy, Odefsey, and Genvoya. Gilead offered discounts for Descovy that resulted into lower net prices compared to Truvada. This strategy encouraged patients switching from Truvada to Descovy before the availability of generic Truvada. Conversely, Gilead offered lower discounts for Odefsey and Genvoya, which resulted into higher net prices compared to Complera and Stribild.

Underprescribing vs underfilling to oral anticoagulation: An analysis of linked medical record and claims data for a nationwide sample of patients with atrial fibrillation

BACKGROUND: Oral anticoagulants (OAC) is indicated for stroke prevention in patients with atrial fibrillation (AF) with a moderate or high risk of stroke. Despite the benefits of stroke prevention, only 50%-60% of Americans with nonvalvular AF and a moderate or high risk of stroke receive OAC medication. OBJECTIVE: To understand the extent to which low OAC use by patients with AF is attributed to underprescribing or underfilling once the medication is prescribed. METHODS: This is a retrospective cohort study that used linked claims data and electronic health records from Optum Integrated data. Participants were adults (aged ≥ 18 years) with first AF between January 2013 and June 2017. The outcomes included (1) being prescribed OACs within 180 days of AF diagnosis or not and (2) filling an OAC prescription or not among patients with AF who were prescribed an OAC within 150 days of AF diagnosis. Multivariable logistic regression models were constructed to determine factors associated with underprescribing and underfilling. RESULTS: Of the 6,141 individuals in the study cohort, 51% were not prescribed OACs within 6 months of their AF diagnosis. Of the 2,956 patients who were prescribed, 19% did not fill it at the pharmacy. In the final adjusted model, younger age, location (Northeast and South), a low CHA₂DS₂-VASc score, and a high HAS-BLED score were associated with a lower likelihood of being prescribed OACs. Among patients who were prescribed, Medicare enrollment (odds ratio [OR] [95% CI] = 2.2 [1.3-3.7]) and having a direct oral anticoagulant prescription (1.5 [1.2-1.9]) were associated with a lower likelihood of filling the prescription. CONCLUSIONS: Both underprescribing and underfilling are major drivers of low OAC use among patients with AF, and solutions to increase OAC use must address both prescribing and filling. DISCLOSURES: Research reported in this study was supported by the National Heart, Lung and Blood Institute (K01HL142847 and R01HL157051). Dr Guo is supported by the National Institute of Diabetes and Digestive and Kidney Diseases (R01DK133465), PhMRA Foundation Research Starter Award, and the University of Florida Research Opportunity Seed Fund. Dr Hernandez reports scientific advisory board fees from Pfizer and Bristol Myers Squibb, outside of the submitted work.

COVID-19 and adherence to biologic therapies for psoriasis: An analysis of nationwide pharmacy claims data

BACKGROUND: Early after the onset of the COVID-19 pandemic, concerns were raised that the use of psoriasis treatments, particularly biologic therapies because of their immunosuppressant effects, could be associated with a poor prognosis in the case of COVID-19 infection. OBJECTIVE: To examine changes in adherence to systematic biologic therapies for psoriasis after the onset of the COVID-19 pandemic. METHODS: Using IQVIA medical and pharmacy claims data from January 1, 2018, to October 31, 2020, we identified patients aged 18 years or older who had a diagnosis of plaque psoriasis in 2018 and who received systemic biologic therapies for psoriasis, including both provider-administered and pharmacy-dispensed therapies. We calculated the incidence of 14-day gaps without therapy per 1,000 study participants for each 30-day interval. We constructed interrupted time series analyses to test changes in the incidence of outcomes after the pandemic declaration. RESULTS: The sample included 15,890 study participants: 45.4% were female and 15.2% were aged 65 years or older. For patients using biologic therapies dispensed from the pharmacy, there was a 13.1% decrease in the incidence of 14-day gaps without biologic therapy immediately after pandemic declaration, from 92.4 gaps per 1,000 patients to 80.2 gaps per 1,000 patients, but this decrease was not statistically significant. However, for patients using provider-administered therapies, the incidence of 14-day gaps without biologic therapy increased by 55.1% after pandemic declaration, from 29.0 gaps per 1,000 patients to 44.9 gaps per 1,000 patients (P < 0.01). CONCLUSIONS: Following the onset of the COVID-19 pandemic, we found an increased incidence of gaps in biologic therapy for psoriasis among users of provider-administered treatments but not among users of pharmacy-dispensed therapies. DISCLOSURES: Dr Hernandez reports personal fees from Bristol Myers Squibb and personal fees from Pfizer outside the submitted work. Dr Hernandez is funded by the National Heart, Lung and Blood Institute (grant K01HL142847). The funder had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication. The statements, findings, conclusions, views, and opinions expressed in this publication are based on data obtained under license from IQVIA as part of the IQVIA Institute's Human Data Science Research Collaborative.

Disparities in distribution of COVID-19 vaccines across US counties: A geographic information system-based cross-sectional study

BACKGROUND

The US Centers for Disease Control and Prevention has repeatedly called for Coronavirus Disease 2019 (COVID-19) vaccine equity. The objective our study was to measure equity in the early distribution of COVID-19 vaccines to healthcare facilities across the US. Specifically, we tested whether the likelihood of a healthcare facility administering COVID-19 vaccines in May 2021 differed by county-level racial composition and degree of urbanicity.

METHODS AND FINDINGS

The outcome was whether an eligible vaccination facility actually administered COVID-19 vaccines as of May 2021, and was defined by spatially matching locations of eligible and actual COVID-19 vaccine administration locations. The outcome was regressed against county-level measures for racial/ethnic composition, urbanicity, income, social vulnerability index, COVID-19 mortality, 2020 election results, and availability of nontraditional vaccination locations using generalized estimating equations. Across the US, 61.4% of eligible healthcare facilities and 76.0% of eligible pharmacies provided COVID-19 vaccinations as of May 2021. Facilities in counties with >42.2% non-Hispanic Black population (i.e., > 95th county percentile of Black race composition) were less likely to serve as COVID-19 vaccine administration locations compared to facilities in counties with <12.5% non-Hispanic Black population (i.e., lower than US average), with OR 0.83; 95% CI, 0.70 to 0.98, p = 0.030. Location of a facility in a rural county (OR 0.82; 95% CI, 0.75 to 0.90, p < 0.001, versus metropolitan county) or in a county in the top quintile of COVID-19 mortality (OR 0.83; 95% CI, 0.75 to 0.93, p = 0.001, versus bottom 4 quintiles) was associated with decreased odds of serving as a COVID-19 vaccine administration location. There was a significant interaction of urbanicity and racial/ethnic composition: In metropolitan counties, facilities in counties with >42.2% non-Hispanic Black population (i.e., >95th county percentile of Black race composition) had 32% (95% CI 14% to 47%, p = 0.001) lower odds of serving as COVID administration facility compared to facilities in counties with below US average Black population. This association between Black composition and odds of a facility serving as vaccine administration facility was not observed in rural or suburban counties. In rural counties, facilities in counties with above US average Hispanic population had 26% (95% CI 11% to 38%, p = 0.002) lower odds of serving as vaccine administration facility compared to facilities in counties with below US average Hispanic population. This association between Hispanic ethnicity and odds of a facility serving as vaccine administration facility was not observed in metropolitan or suburban counties. Our analyses did not include nontraditional vaccination sites and are based on data as of May 2021, thus they represent the early distribution of COVID-19 vaccines. Our results based on this cross-sectional analysis may not be generalizable to later phases of the COVID-19 vaccine distribution process.

CONCLUSIONS

Healthcare facilities in counties with higher Black composition, in rural areas, and in hardest-hit communities were less likely to serve as COVID-19 vaccine administration locations in May 2021. The lower uptake of COVID-19 vaccinations among minority populations and rural areas has been attributed to vaccine hesitancy; however, decreased access to vaccination sites may be an additional overlooked barrier.

Association of formulary restrictions and initiation of an SGLT2i or GLP1-RA among Medicare beneficiaries with type 2 diabetes

BACKGROUND

Use of SGLT2 inhibitors (SGLT2i) and GLP-1 receptor agonists (GLP1-RA) among older adults with type 2 diabetes (T2D) has been limited.

OBJECTIVE

To examine factors associated with initiation of an SGLT2i or GLP-1RA among Medicare beneficiaries with T2D in the early years after their market approval, with a particular focus on formulary restrictions (e.g. prior authorization, step therapy requirements, higher co-pays).

METHODS

A retrospective cohort study using data from a 5% random sample of Medicare beneficiaries with T2D followed from 1/1/2015-12/31/16. Formulary restrictiveness was defined as: (1) the number of target drugs (i.e. SGLT2is or GLP1-RAs) included in tiers 1-3 of a beneficiary's formulary (greater number of drugs in tiers 1-3 being less restrictive) and (2) the number of drugs without prior authorization or step therapy (requirement to try less expensive drugs prior to "stepping up" to more expensive therapies). We used multivariable logistic regression models to estimate the association between measures of formulary restrictiveness and initiation of a target drug, controlling for patient demographics, diabetes duration, clinical comorbidities, and provider specialty.

RESULTS

Among 112,985 beneficiaries with T2D, 5,619 (5%) initiated an SGLT2i or GLP1-RA. After adjusting for baseline characteristics, patients enrolled in formularies with ≥ 2 target drugs available in tiers 1-3 had 17% higher odds of initiating an SGLT2i or GLP1-RA (aOR 1.17, 95% CI 1.05-1.31) compared to patients enrolled in formularies with 0 drugs available in tiers 1-3. There was no significant association between the number of drugs without prior authorization or step therapy requirements and initiation of a target drug (aOR 0.96, 95% CI, 0.85-1.09). Age 75 years or older (vs < 65, aOR 0.23, 95% CI 0.21-0.26) and black race (vs white, aOR 0.65, 95% CI 0.59-0.71) were associated with lower odds of initiating a target drug.

CONCLUSIONS

Having a greater number of target drugs available on less expensive formulary tiers is associated with increased odds of initiating an SGLT2i or GLP-1RA among Medicare beneficiaries with T2D.

Identifying Patients at Risk of Acute Kidney Injury Among Medicare Beneficiaries With Type 2 Diabetes Initiating SGLT2 Inhibitors: A Machine Learning Approach

Introduction: To predict acute kidney injury (AKI) risk in patients with type 2 diabetes (T2D) prescribed sodium-glucose cotransporter two inhibitors (SGLT2i).

Methods: Using a 5% random sample of Medicare claims data, we identified 17,694 patients who filled ≥1 prescriptions for canagliflozin, dapagliflozin and empagliflozin in 2013–2016. The cohort was split randomly and equally into training and testing sets. We measured 65 predictor candidates using claims data from the year prior to SGLT2i initiation. We then applied three machine learning models, including random forests (RF), elastic net and least absolute shrinkage and selection operator (LASSO) for risk prediction.

Results: The incidence rate of AKI was 1.1% over a median 1.5 year follow up. Among three machine learning methods, RF produced the best prediction (C-statistic = 0.72), followed by LASSO and elastic net (both C-statistics = 0.69). Among individuals classified in the top 10% of the RF risk score (i.e., high risk group), the actual incidence rate of AKI was as high as 3.7%. In the logistic regression model including 14 important risk factors selected by LASSO, use of loop diuretics [adjusted odds ratio (95% confidence interval): 3.72 (2.44–5.76)] had the strongest association with AKI incidence.

Disscusion: Our machine learning model efficiently identified patients at risk of AKI among Medicare beneficiaries with T2D undergoing SGLT2i treatment.

Comparison of oral anticoagulation use and adherence among Medicare beneficiaries enrolled in stand-alone prescription drug plans vs Medicare Advantage prescription drug plans

BACKGROUND: For atrial fibrillation (AF) patients, oral anticoagulants (OACs) can reduce the risk of stroke by 60%; however, nearly 50% of patients recommended to receive OACs do not receive therapy. Integrated insurers that cover pharmacy and medical benefits may be incentivized to improve OAC use and adherence because they benefit from offsets in medical costs associated with prevented strokes. OBJECTIVE: To compare OAC use and adherence between AF patients enrolled in Medicare stand-alone prescription drug plans (PDPs), which only cover pharmacy benefits, and those enrolled in Medicare Advantage prescription drug (MAPD) plans, which cover medical and pharmacy benefits. METHODS: This was a retrospective cohort study, conducted using 2014-2016 Medicare claims data from the Centers for Medicare & Medicaid Services and a large regional health plan in Pennsylvania. Primary outcomes included OAC use and OAC adherence. OAC use was measured as filling at least 1 prescription for an OAC after AF diagnosis. OAC adherence was defined as having greater than or equal to 80% of days covered with an OAC. We constructed conditional logistic regression models in propensity score-matched samples to test the association between enrollment in PDPs or MAPD plans and outcomes. RESULTS: There were 2,551 AF patients enrolled in PDPs and 4,502 in MAPD plans before propensity score matching. The propensity score-matched sample included 2,537 patients in each group. OAC use was higher among MAPD beneficiaries (74%-76%) compared with PDP beneficiaries (70%; P < 0.001), and 41%-42% of MAPD beneficiaries were adherent to OACs, compared with 34% of PDP beneficiaries (P < 0.001). In adjusted analyses among propensity score-matched samples, PDP enrollment was associated with lower odds of OAC use (OR = 0.67, 95% CI = 0.56-0.81) and adherence (OR = 0.68, 95% CI = 0.59-0.78) compared with MAPD enrollment. CONCLUSIONS: AF patients enrolled in MAPD plans were more likely to use and adhere to OACs compared with PDP enrollees. These results may reflect the financial incentives of MAPD plans to improve guideline-recommended OAC use, since MAPD insurers bear the risk of pharmacy and medical costs and thus may benefit from cost savings associated with averted stroke events. As efforts to improve use and adherence of OACs in AF patients increase, focus should be given to how insurance benefit designs can affect medication use. DISCLOSURES: No outside funding supported this study. Hernandez has received personal fees from BMS and Pfizer, unrelated to this study. The other authors have nothing to disclose.

Effect of the COVID-19 pandemic on adversity in individuals receiving anticoagulation for atrial fibrillation: A nationally representative administrative health claims analysis

Background

Atrial fibrillation (AF) is strongly associated with clinical adversity, including increased hospitalization and bleeding and stroke events. We examined the effect of the SARS-2 Coronavirus 2019 (COVID-19) pandemic on such events in individuals with AF receiving oral anticoagulation.

Methods

We employed medical and pharmacy claims spanning 2018–2020 from a nationally representative U.S. database (IQVIA Longitudinal Prescription, Medical Claims, and Institutional Claims). We selected individuals receiving oral anticoagulation in 2018 for AF and followed them from 1/1/2019–7/8/2020 for clinical events. We constructed interrupted time-series analyses across 30-day intervals with Poisson regression models to determine the effect of the COVID-19 pandemic on clinical events.

Results

The dataset included 1,439,145 individuals (half with age ≥75 years; 47.6% women) receiving oral anticoagulation. We determined a 19% decrease in emergency room visits following the pandemic declaration and 8% decrease in inpatient admissions. In contrast admissions for stroke and bleeding were not affected by the declaration of the pandemic.

Discussion

These results describe the temporal effect of the COVID-19 pandemic on clinical adversity – hospitalizations, strokes, and bleeding events – in individuals receiving oral anticoagulation for AF. Our analysis quantifies the decrease in clinical adversity accompanying COVID-19 in a large, highly representative U.S. health claims database.

COVID-19 and Anticoagulation for Atrial Fibrillation: An Analysis of US Nationwide Pharmacy Claims Data

Background

Adherence to oral anticoagulation (OAC) is critical for stroke prevention in atrial fibrillation. However, the COVID‐19 pandemic may have disrupted access to such therapy. We hypothesized that our analysis of a US nationally representative pharmacy claims database would identify increased incidence of lapses in OAC refills during the COVID‐19 pandemic.

Methods and Results

We identified individuals with atrial fibrillation prescribed OAC in 2018. We used pharmacy dispensing records to determine the incidence of 7‐day OAC gaps and 15‐day excess supply for each 30‐day interval from January 1, 2019 to July 8, 2020. We constructed interrupted time series analyses to test changes in gaps and supply around the pandemic declaration by the World Health Organization (March 11, 2020), and whether such changes differed by medication (warfarin or direct OAC), prescription payment type, or prescriber specialty. We identified 1 301 074 individuals (47.5% women; 54% age ≥75 years). Immediately following the COVID‐19 pandemic declaration, we observed a 14% decrease in 7‐day OAC gaps and 56% increase in 15‐day excess supply (both P<0.001). The increase in 15‐day excess supply was more marked for direct OAC (69% increase) than warfarin users (35%; P<0.001); Medicare beneficiaries (62%) than those with commercial insurance (43%; P<0.001); and those prescribed OAC by a cardiologist (64%) rather than a primary care provider (48%; P<0.001).

Conclusions

Our analysis of nationwide claims data demonstrated increased OAC possession after the onset of the COVID‐19 pandemic. Our findings may have been driven by waivers of early refill limits and patients’ tendency to stockpile medications in the first weeks of the pandemic.

Racial and Urban-Rural Difference in the Frequency of Ischemic Stroke as Initial Manifestation of Atrial Fibrillation

Objective: Atrial fibrillation (AF) may remain undiagnosed until the development of complications. We aimed to examine the epidemiology and racial/ethnic and rural/urban differences in the frequency of newly diagnosed AF manifesting as ischemic stroke in a nationally representative sample of Medicare beneficiaries.

Methods: We used a 5% random sample of Medicare claims to identify patients newly diagnosed with AF in 2016. The primary dependent variable was stroke or transient ischemic attack (TIA) in the 7 days prior to the first AF diagnosis, i.e., stroke or TIA as the initial manifestation of AF. We constructed a multivariable logistic regression to quantify the association between race/ethnicity, urban/rural residence, and the primary dependent variable.

Results: Among 39,409 patients newly diagnosed with AF (mean age 77 ± 10 years; 58% women; 7.2% Black, 87.8% White, 5.1% others), 2,819 (7.2%) had ischemic stroke or TIA in the 7 days prior to AF diagnosis. Black patients (adjusted OR [95% CI]: 1.21 [1.05, 1.40], vs. White) and urban residents (1.21 [1.08, 1.35], vs. rural) were at increased risk of stroke as the initial manifestation of AF. Racial differences were larger among patients aged ≥75 years, with adjusted ORs of 1.43 (1.19, 1.73) for Black vs. White patients, but non-significant for those aged <75 (P for interaction = 0.03).

Conclusion: We observed significant and important differences in the risk of stroke as initial manifestation of AF between White and Black patients and between rural and urban residents. Our results suggest potential disparities in the identification AF across race/ethnicity groups and urban/rural areas.

Joint Latent Class Analysis of Oral Anticoagulation Use and Risk of Stroke or Systemic Thromboembolism in Patients with Atrial Fibrillation

BACKGROUND

Oral anticoagulation (OAC) is recommended to reduce the risk of stroke or systemic thromboembolism (TE) in atrial fibrillation (AF). In this study, we applied novel joint latent class mixed models to identify heterogeneous patterns of trajectories of OAC use and determined how these trajectories are associated with risks of thromboembolic outcomes.

METHODS AND RESULTS

We used 2013-2016 claims data from a 5% random sample of Medicare beneficiaries, obtained from the Centers for Medicare and Medicaid Services. Our study sample included 16,399 patients newly diagnosed with AF in 2014-2015 who were followed for 12 months after the first AF diagnosis and filled at least one OAC prescription in this time period. OAC use was defined as the number of days covered with OACs every 30-day interval after the first AF diagnosis. We used a joint latent class mixed model to simultaneously evaluate the longitudinal patterns of OAC use and time to stroke or TE, while adjusting for age, race, CHAD2S2-VASc score and HAS-BLED score. Five classes of OAC use patterns were identified: late users (17.8%); late initiators (12.5%); early discontinuers (18.6%); late discontinuers (15.4%); and continuous users (35.6%). Compared with continuous users, the risk of stroke or TE was higher for participants in the late initiators (hazard ratio [HR] 1.73, 95% confidence interval [CI] 1.49-2.01) and late discontinuers (HR 1.23, 95% CI 1.04-1.45) classes.

CONCLUSION

Late initiators and late discontinuers had a higher risk of stroke or TE than continuous users. Early initiation and continuous OAC use is important in preventing stroke and TE among patients diagnosed with AF.

Online hate network spreads malicious COVID-19 content outside the control of individual social media platforms

We show that malicious COVID-19 content, including racism, disinformation, and misinformation, exploits the multiverse of online hate to spread quickly beyond the control of any individual social media platform. We provide a first mapping of the online hate network across six major social media platforms. We demonstrate how malicious content can travel across this network in ways that subvert platform moderation efforts. Machine learning topic analysis shows quantitatively how online hate communities are sharpening COVID-19 as a weapon, with topics evolving rapidly and content becoming increasingly coherent. Based on mathematical modeling, we provide predictions of how changes to content moderation policies can slow the spread of malicious content.

Using machine learning to identify diabetes patients with canagliflozin prescriptions at high-risk of lower extremity amputation using real-world data

AIMS

Canagliflozin, a sodium-glucose cotransporter 2 inhibitor indicated for lowering glucose, has been increasingly used in diabetes patients because of its beneficial effects on cardiovascular and renal outcomes. However, clinical trials have documented an increased risk of lower extremity amputations (LEA) associated with canagliflozin. We applied machine learning methods to predict LEA among diabetes patients treated with canagliflozin.

METHODS

Using claims data from a 5% random sample of Medicare beneficiaries, we identified 13 904 diabetes individuals initiating canagliflozin between April 2013 and December 2016. The samples were randomly and equally split into training and testing sets. We identified 41 predictor candidates using information from the year prior to canagliflozin initiation, and applied four machine learning approaches (elastic net, least absolute shrinkage and selection operator [LASSO], gradient boosting machine and random forests) to predict LEA risk after canagliflozin initiation.

RESULTS

The incidence rate of LEA was 0.57% over a median 1.5 years follow-up. LASSO produced the best prediction, yielding a C-statistic of 0.81 (95% CI: 0.76, 0.86). Among individuals categorized in the top 5% of the risk score, the actual incidence rate of LEA was 3.74%. Among the 16 factors selected by LASSO, history of LEA [adjusted odds ratio (aOR): 33.6 (13.8, 81.9)] and loop diuretic use [aOR: 3.6 (1.8,7.3)] had the strongest associations with LEA incidence.

CONCLUSIONS

Our machine learning model efficiently predicted the risk of LEA among diabetes patients undergoing canagliflozin treatment. The risk score may support optimized treatment decisions and thus improve health outcomes of diabetes patients.

Evaluation of Frequency of Encounters With Primary Care Physicians vs Visits to Community Pharmacies Among Medicare Beneficiaries

IMPORTANCE

The shift toward value-based care has placed emphasis on preventive care and chronic disease management services delivered by multidisciplinary health care teams. Community pharmacists are particularly well positioned to deliver these services due to their accessibility.

OBJECTIVE

To compare the number of patient visits to community pharmacies and the number of encounters with primary care physicians among Medicare beneficiaries who actively access health care services.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study analyzed a 5% random sample of 2016 Medicare beneficiaries from January 1, 2016, to December 31, 2016 (N = 2 794 078). Data were analyzed from October 23, 2019, to December 20, 2019. Medicare Part D beneficiaries who were continuously enrolled and had at least 1 pharmacy claim and 1 encounter with a primary care physician were included in the final analysis (n = 681 456). Those excluded from the study were patients who were not continuously enrolled in Part D until death, those with Part B skilled nursing claims, and those with Part D mail-order pharmacy claims.

EXPOSURES

We conducted analyses for the overall sample and for subgroups defined by demographics, region of residence, and clinical characteristics.

MAIN OUTCOMES AND MEASURES

Outcomes included the number of visits to community pharmacies and encounters with primary care physicians. Unique visits to the community pharmacy were defined using a 13-day window between individual prescription drug claims. Kruskal-Wallis tests were used to compare the medians for the 2 outcomes.

RESULTS

A total of 681 456 patients (mean [SD] age, 72.0 [12.5] years; 418 685 [61.4%] women and 262 771 [38.6%] men) were included in the analysis; 82.2% were white, 9.6% were black, 2.4% were Hispanic, and 5.7% were other races/ethnicities. Visits to the community pharmacy outnumbered encounters with primary care physicians (median [interquartile range (IQR)], 13 [9-17] vs 7 [4-14]; P < .001). The number of pharmacy visits was significantly larger than the number of primary care physician encounters for all subgroups evaluated except for those with acute myocardial infarction (median [IQR], 15 [12-19] vs 14 [7-26]; P = .60 using a 13-day window). The difference in the number of pharmacy and primary care physician encounters was larger in rural areas (median [IQR], 14 [10-17] vs 5 [2-11]; P < .001) than in metropolitan areas (median [IQR], 13 [8-17] vs 8 [4-14]; P < .001). In all 50 states and in all but 9 counties, the number of community pharmacy visits was larger than the number of encounters with primary care physicians.

CONCLUSIONS AND RELEVANCE

This cross-sectional study suggests that community pharmacists are accessible health care professionals with frequent opportunities to interact with community-dwelling patients. Primary care physicians should work collaboratively with community pharmacists, who can assist in the delivery of preventive care and chronic disease management.

Abstract P2-16-07: hMMP9 as Predictive Factor for Response and Progression Free Survival in Breast Cancer Patients Treated with Bevacizumab and Pegylated Liposomal Doxorubicin (PLD)

Background: The anti-angiogenic drug, bevacizumab (Bv), is currently used in the treatment of different malignancies including breast cancer. Many angiogenesis-associated molecules are found in the circulation of cancer patients. Until now, there are no prognostic or predictive factors identified in breast cancer patients treated with Bv. We present here the first results of the prospective monitoring of 6 angiogenesis-related molecules in the peripheral blood of breast cancer patients treated with a combination of Bv and PLD in the phase II trial, SAKK 24/06. Methods: Patients were treated with PLD (20 mg/m2) and Bv (10 mg/kg) on days 1 and 15 of each 4-week cycle for a maximum of 6 cycles, followed by Bv monotherapy maintenance (10 mg/m2 q2 weeks) until progression or severe toxicity. Plasma and serum samples were collected at baseline, after 2 months of therapy, then every 3 months and at treatment discontinuation. Enzyme-linked immunosorbent assays (Quantikine, R&D Systems and Reliatech) were used to measure the expression levels of human vascular endothelial growth factor (hVEGF), placental growth factor (hPlGF), matrix metalloproteinase 9 (hMMP9) and soluble VEGF receptors hsVEGFR-1, hsVEGFR-2 and hsVEGFR-3. The log-transformed data (to reduce the skewness) for each marker was analyzed using an analysis of variance (ANOVA) model to determine if there was a difference between the mean of the subgroups of interest (where α = 0.05). The untransformed data was also analyzed in the same manner as a “sensitivity” check.

Results: 132 blood samples were collected in 41 out of 43 enrolled patients. Baseline levels of the molecules were compared to disease status according to RECIST. There was a statistically significant difference in the mean of the log-transformed levels of hMMP9 between responders [CR+PR] versus the mean in patients with PD (p-value=0.0004, log fold change=0.7536), and between patients with disease control [CR+PR+SD] and those with PD (p-value=&lt;0.0001, log fold change=0.81559), with the log-transformed level of hMMP9 being higher for the responder group. The mean of the log-transformed levels of hsVEGFR-1 was statistically significantly different between patients with disease control [CR+PR+SD] and those with PD (p-value=0.0068, log fold change=-0.6089), where the log-transformed level of hsVEGFR-1 was lower for the responder group. The log-transformed level of hMMP9 at baseline was identified as a significant prognostic factor in terms of progression free survival (PFS): p-value=0.0417, hazard ratio (HR)=0.574 with a corresponding 95% confidence interval (0.336 — 0.979)). No strong correlation was shown either between the log-transformed levels of hsVEGF, hPlGF, hsVEGFR-2 or hsVEGFR-3 and clinical response or the occurrence of severe toxicity, or between the levels of the different molecules.

Conclusions: Our results suggest that baseline plasma level of the matrix metalloproteinase, hMMP9, could predict tumor response and PFS in patients treated with a combination of Bv and PLD. These data justify further investigation in breast cancer patients treated with anti-angiogenic therapy.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P2-16-07.

Effects of ageing on the biomechanical properties of rat articular cartilage

Previous studies have demonstrated that male Sprague Dawley (SD) rats experience age-related bone loss with the same characteristics as that in ageing men. As articular cartilage, like bone, is a critical component of the health and function of the musculoskeletal system, the authors hypothesized that articular cartilage in the untreated male SD rats could be a suitable model for studying the age-related deterioration of articular cartilage in men. To test this hypothesis, male SD rats were killed at between 6 and 27 months. The right femur of each rat was removed. The effects of ageing on the structural integrity of the distal femoral articular cartilage were studied by biomechanical testing with a creep indentation apparatus. The aggregate modulus, Poisson's ratio, permeability, thickness, and percentage recovery of articular cartilage were determined using finite element/non-linear optimization modelling. No significant differences were observed in these biomechanical properties of the distal femoral articular cartilage as a function of age. Therefore, untreated male SD rats appear to be unsuitable for studying the age-related changes of articular cartilage as they occur in men. However, and more intriguingly, it is also possible that ageing does not affect the biomechanical properties of articular cartilage in the absence of cartilage pathology.

Electrical stimulation for gastroparesis

BACKGROUND

Gastroparesis is a disabling, and sometimes fatal, disease that often does not respond to medical treatment. This single-surgeon prospective study examines the safety and 6-month efficacy of electrical stimulation for the treatment of gastroparesis.

METHODS

Sixteen patients with medically refractory gastroparesis underwent laparoscopic implantation of an electrical stimulator device (Enterra Therapy, Medtronic, Minneapolis, MN, USA) consisting of a subcutaneous stimulator and two gastric wall leads. Gastric emptying scans (GES) confirmed the diagnosis of gastroparesis. Patients were evaluated preoperatively using a self-administered GI symptomatology questionnaire and RAND 36 Health Survey. Once patients were >6-months from implantation, a repeat GES was obtained and patients completed a postoperative GI symptomatology questionnaire and RAND 36 Health Survey. Ten of 16 patients in this case series were >6-months from implantation. One was lost to follow-up. An F-test was used to establish equality of standard deviations between the 16 patients evaluated preoperatively and the subset of 10 patients evaluated postoperatively. A Student's t-test was used to evaluate the significance of differences in pre- and postoperative results.

RESULTS

Average operating time was 117 min with no intraoperative complications. The majority of patients were discharged on postoperative day 1. There were two complications in the postoperative period. Patients experienced a significant decrease in nausea and vomiting as measured by the GI symptomatology questionnaire. Half of all patients no longer required gastric prokinetic medications and there was a subjective reduction of pyrosis, early satiety, and epigastric pain. A significant increase in quality of life as measured by the RAND 36 Health Survey was seen, and six of eight patients no longer demonstrated gastroparesis on GES.

CONCLUSION

Laparoscopic implantation of an electrical stimulation device is a safe and effective treatment by subjective and objective standards for the management of medically refractory gastroparesis.

Telementoring and teleproctoring

Telemedicine has previously been defined as "live two-way interactive video communication between a physician and a patient and/or another physician, where all participants are able to see and hear one another much like a face to face encounter." This concept has gained recent notoriety because of the great advances in telecommunications and the potential future increased cost-effectiveness associated with its utilization. We have developed a telementoring deployment protocol that can be effectively used to introduce a student to telementoring processes. The strict protocol uses military commands to facilitate smooth information transfer. The use of a concept called tactical information deployment provides the surgeon with rapid access to reference information in the operating suite. Multimedia interactive CD-ROMs, with digitized movie clips, illustrations, sound bits, and the latest academic review of the literature arm the surgeon with a database that establishes an unprecedented clinical adaptive capability (CAC). The availability of this information is invaluable to surgeons in their initial advanced laparoscopic procedural efforts. Telementoring simulator opportunities are included to acclimate the participant to the process. If the process seems comprehensive, it is meant to be. This is a high-risk situation, and a patient's welfare is on the line. If this concept is to reach its maximal healthcare delivery potential, responsible and academically credible training programs should be established with directional guidelines.

Vocal cord paralysis following carotid endarterectomy: the paradox of return of function

In a series of 411 consecutive carotid endarterectomies 29 patients were identified with vocal cord paralysis. All patients were symptomatic, although in many these symptoms were subtle and rapidly resolved. There was a statistically significant predominance of left-sided paralysis. Excluding three patients who died during the initial year of follow-up return of normal voice was noted in 22 patients, but complete return of vocal cord function was present in only 15. Apposition of the contralateral vocal cord against a paralyzed vocal cord allowed for production of normal voice in five patients. Less than 1% of patients remained with symptoms at one year following endarterectomy. We conclude that vocal cord paralysis is a common complication of carotid endarterectomy; the voice becomes an unreliable guide as to its resolution. We recommend laryngoscopic examination of all patients who undergo bilateral carotid endarterectomy.

T lymphocytes of the normal human cornea

Lymphocytes in the periphery of the normal human cornea are identified as being only T lymphocytes by immunohistochemical methods. OKT-4 positive cells (T-helper/inducer lymphocytes) and OKT-8 positive cells (T-suppressor/cytotoxic lymphocytes) are found in similar numbers in most of the corneas examined. OKT-4 positive cells in the cornea present a risk of transferring HTLV-III (HIV) by corneal grafting.