Dosage Frequency Effects on Treatment Outcomes Following Self-managed Digital Therapy: Retrospective Cohort Study.

BACKGROUND: Although the efficacy of high-dose speech-language therapy (SLT) for individuals with poststroke aphasia has been established in the literature, there is a gap in translating these research findings to clinical practice. Therefore, patients continue to receive suboptimal amounts of SLT, with negative consequences for their functional communication recovery. Recent research has identified self-managed digital health technology as one way to close the dosage gap by enabling high-intensity therapy unrestricted by clinician availability or other practical constraints. However, there is limited empirical evidence available to rehabilitation professionals to guide dose prescriptions for self-managed SLT despite their increasing use in the COVID-19 era and likely beyond. OBJECTIVE: This study aims to leverage real-world mobile health data to investigate the effects of varied dosage frequency on performance outcomes for individuals with poststroke speech, language, and cognitive deficits following a 10-week period of self-managed treatment via a commercially available digital health platform. METHODS: Anonymized data from 2249 poststroke survivors who used the Constant Therapy app between late 2016 and 2019 were analyzed. The data included therapy tasks spanning 13 different language and cognitive skill domains. For each patient, the weekly therapy dosage was calculated based on the median number of days per week of app use over the 10-week therapy period, binned into groups of 1, 2, 3, 4, or ≥5 days per week. Linear mixed-effects models were run to examine change in performance over time as a function of dosage group, with post hoc comparisons of slopes to evaluate the performance gain associated with each additional day of practice. RESULTS: Across all skill domains, linear mixed-effects model results showed that performance improvement was significantly greater for patients who practiced 2 (ß=.001; t15,355=2.37; P=.02), 3 (ß=.003; t9738=5.21; P<.001), 4 (ß=.005; t9289=7.82; P<.001), or ≥5 (ß=.005; t6343=8.14; P<.001) days per week compared with those who only practiced for 1 day per week. Post hoc comparisons confirmed an incremental dosage effect accumulating with each day of practice (ie, 1 day vs 2 days, 2 days vs 3 days, and 3 days vs 4 days), apart from 4 days versus ≥5 days of practice per week. The result of greater improvement for higher versus lower dosage frequency groups was true not only across all domains but also within a majority of individual subdomains. CONCLUSIONS: The findings from this study demonstrated that increased dosage frequency is associated with greater therapy gains over a 10-week treatment period of self-managed digital therapy. The use of real-world data maximizes the ecological validity of study results and makes the findings more generalizable to clinical settings. This study represents an important step toward the development of optimal dose recommendations for self-managed SLT.

Closing the Digital Divide in Speech, Language, and Cognitive Therapy: Cohort Study of the Factors Associated With Technology Usage for Rehabilitation.

BACKGROUND: For stroke, traumatic brain injury (TBI), and other neurologic conditions associated with speech-language disorders, speech and language therapy is the standard of care for promoting recovery. However, barriers such as clinician time constraints and insurance reimbursement can inhibit a patient's ability to receive the support needed to optimize functional gain. Although digital rehabilitation has the potential to increase access to therapy by allowing patients to practice at home, the clinical and demographic characteristics that impact a patient's level of engagement with technology-based therapy are currently unknown. OBJECTIVE: This study aimed to evaluate whether the level of engagement with digital therapy differs by various patient characteristics, including age, gender, diagnosis, time from disease onset, and geographic location (urban vs rural). METHODS: Data for patients with stroke or TBI that initiated the use of Constant Therapy, a remotely delivered, cloud-based rehabilitation program for patients with speech-language disorders, were retrospectively analyzed. Only data from therapeutic sessions completed at home were included. The following three activity metrics were evaluated: (1) the number of active weeks of therapy, (2) the average number of active therapy days per week, and (3) the total number of therapeutic sessions completed during the first 20 weeks of program access. An active day or week was defined as having at least one completed therapeutic session. Separate multiple linear regression models were performed with each activity measure as the dependent variable and all available patient demographics as model covariates. RESULTS: Data for 2850 patients with stroke or TBI were analyzed, with the average patient completing 8.6 weeks of therapy at a frequency of 1.5 days per week. Contrary to known barriers to technological adoption, older patients were more active during their first 20 weeks of program access, with those aged 51 to 70 years completing 5.01 more sessions than patients aged 50 years or younger (P=.04). Similarly, patients living in a rural area, who face greater barriers to clinic access, were more digitally engaged than their urban counterparts, with rural patients completing 11.54 more (P=.001) sessions during their first 20 weeks of access, after controlling for other model covariates. CONCLUSIONS: An evaluation of real-world data demonstrated that patients with stroke and TBI use digital therapy frequently for cognitive and language rehabilitation at home. Usage was higher in areas with limited access to clinical services and was unaffected by typical barriers to technological adoption, such as age. These findings will help guide the direction of future research in digital rehabilitation therapy, including the impact of demographics on recovery outcomes and the design of large, randomized controlled trials.

Development and validation of a claims-based measure as an indicator for disease status in patients with multiple sclerosis treated with disease-modifying drugs.

BACKGROUND: Administrative healthcare claims data provide a mechanism for assessing and monitoring multiple sclerosis (MS) disease status across large, clinically representative "real-world" populations. The estimation of MS disease status using administrative claims can be a challenge, however, due to a lack of detailed clinical information. Retrospective claims analyses in MS have traditionally used rates of MS relapses to approximate disease status. Healthcare costs may be alternate, broader claims-based indicators of disease activity because costs reflect multiple facets of care of patients with MS, and there is a strong correlation between quality of life of patients with MS and costs of the disease. This study developed, tested, and validated a healthcare cost-based measure to serve as an indicator of overall disease status in patients with MS treated with disease-modifying drugs (DMDs) utilizing administrative claims. METHODS: Using IMS Health Real World Data Adjudicated Claims - US data (January 2006-June 2013), a negative binomial regression predicted annual all-cause medical costs. Coefficients reaching statistical significance (p < 0.05) and increasing costs by ≥5% were selected for inclusion into an MS-specific severity score (scale of 0 to 100). Components of the score included rehabilitation services, altered mental state, pain, disability, stiffness, balance disorder, urinary incontinence, numbness, malaise/fatigue, and infections. Coefficient weights represented each predictor's contribution. The predictive model was derived using 50% of a random sample and tested/validated using the remaining 50%. RESULTS: Average overall predicted annual total medical cost was $11,134 (development sample, n = 11,384, vs. $10,528 actual) and $11,303 (validation sample, n = 11,385, vs. $10,620 actual). The model had consistent bias (approximately +$600 or +6% of actual costs) for both samples. In the validation sample, mean MS disease status scores were 0.24, 8.95, and 21.77 for low, medium, and high tertiles, respectively. Mean costs were most accurately predicted among less severe patients ($5243 predicted vs. $5233 actual cost for lowest tertile). CONCLUSION: The algorithm developed in this study provides an initial step to helping understand and potentially predict cost changes for a commercially insured MS population.

Economic Evaluation of Linaclotide for the Treatment of Adult Patients With Chronic Idiopathic Constipation in the United States.

PURPOSE: To evaluate the effectiveness and costs of linaclotide (Linzess) versus lubiprostone (Amitiza) in the treatment of adult patients with chronic idiopathic constipation (CIC). DESIGN: A decision-tree model using model inputs derived from published literature, linaclotide phase 3 trial data, and a physician survey. METHODOLOGY: Measures of treatment efficacy were selected based on comparability between trial data, with posthoc analyses of linaclotide required to ensure comparability with available lubiprostone data. Response to therapy was defined as (1) having one of the best two satisfaction answers of a 5-point global treatment satisfaction scale at Week 4 or (2) having a weekly spontaneous bowel movement (SBM) frequency 4 at Week 4. Patients who do not respond to therapy are assumed to accrue costs associated with a treatment failure. Model time horizon is aligned with the lubiprostone clinical trial duration of 4 weeks. Model outputs include response rates, quality-adjusted life-years (QALYs) and direct costs. RESULTS: Linaclotide was associated with lower per-patient costs vs lubiprostone for both definitions of response ($946 vs $1,015 for global assessment and $727 vs $737 for SBM frequency). When treatment response was based on a global assessment of treatment satisfaction, linaclotide was associated with higher effectiveness (response: 39.3% vs 35.0%). For SBM frequency, linaclotide was slightly less effective compared to lubiprostone (response: 58.6% vs 59.6%), but also less costly. Base-case results were robust in sensitivity analysis. CONCLUSIONS: Linaclotide is less expensive with similar effectiveness when compared to lubiprostone for the treatment of CIC in adult patients.

Recurrent hospitalization and healthcare resource use among patients with deep vein thrombosis and pulmonary embolism: findings from a multi-payer analysis.

The objective of this study was to assess deep vein thrombosis and pulmonary embolism (DVT/PE) recurrence rates and resource utilization among patients with an initial DVT or PE event across multiple payer perspectives. Retrospective analyses were performed using a software tool that analyzes health plan claims to evaluate treatment patterns and resource utilization for various cardiovascular conditions. Six databases were analyzed from three payer perspectives (Commercial, Medicare, and Medicaid). Patients were ≥18 years old with a primary diagnosis of DVT or PE associated with an inpatient and/or emergency room claim, had received an antithrombotic within 7 days before or 14 days after index, and had no diagnosis of atrial fibrillation during follow-up. Outcomes were assessed over a 1 year period following index. More PE patients were hospitalized for their index event than DVT patients (42-59 % DVT and 69-86 % PE) and had longer mean length of stay (2.35-2.95 days DVT and 3.26-3.76 days PE). Recurrent event rates among PE patients (12-32 %) were higher than those for DVT patients (6-16 %) across all payers. The highest rate of recurrence was observed among the Medicaid population [23 % overall (VTE); 16 % DVT; 32 % PE]. All-cause hospitalization in the year following their VTE episode occurred in 23-67 % DVT patients and 30-68 % PE patients. Medicaid had the highest proportion of patients with hospitalizations and ER visits. Recurrent VTE events and all-cause hospitalizations are relatively common, especially for patients who had a PE, and among those in the Medicaid payer population.

Adherence to Blood Cholesterol Treatment Guidelines Among Physicians Managing Patients With Atherosclerotic Cardiovascular Disease.

The ACC/AHA blood cholesterol treatment guidelines recommend statin therapy for all patients after experiencing an acute cardiovascular event. Previous analyses have shown that physicians have been slow to adopt guidelines, and many patients remain untreated or undertreated with statins after a cardiovascular event. However, reasons for this remain unknown. This analysis used electronic medical records and patient chart data from Reliant Medical Group (Worcester, Massachusetts) to evaluate physician adherence to the 2013 ACC/AHA blood cholesterol guidelines when treating patients with evidence of acute atherosclerotic cardiovascular disease and the reasons for the observed treatment decisions. Less than 50% of acute atherosclerotic cardiovascular disease patients were treated according to the ACC/AHA guidelines. Nearly 42% of patients not treated according to guidelines received a lower statin intensity than recommended. The most common reason cited by 41.8% of physicians for treating with a statin intensity below the recommended intensity was low-density lipoprotein cholesterol stable or at goal, despite ACC/AHA guidelines recommending specific statin intensities rather than specific low-density lipoprotein cholesterol levels. In conclusion, physician and patient education on the importance of maximizing lipid-lowering therapy in this high-risk patient population should be emphasized.

Detecting reports of unsafe foods in consumer product reviews.

OBJECTIVES: Access to safe and nutritious food is essential for good health. However, food can become unsafe due to contamination with pathogens, chemicals or toxins, or mislabeling of allergens. Illness resulting from the consumption of unsafe foods is a global health problem. Here, we develop a machine learning approach for detecting reports of unsafe food products in consumer product reviews from Amazon.com. MATERIALS AND METHODS: We linked Amazon.com food product reviews to Food and Drug Administration (FDA) food recalls from 2012 to 2014 using text matching approaches in a PostGres relational database. We applied machine learning methods and over- and under-sampling methods to the linked data to automate the detection of reports of unsafe food products. RESULTS: Our data consisted of 1 297 156 product reviews from Amazon.com. Only 5149 (0.4%) were linked to recalled food products. Bidirectional Encoder Representation from Transformations performed best in identifying unsafe food reviews, achieving an F1 score, precision and recall of 0.74, 0.78, and 0.71, respectively. We also identified synonyms for terms associated with FDA recalls in more than 20 000 reviews, most of which were associated with nonrecalled products. This might suggest that many more products should have been recalled or investigated. DISCUSSION AND CONCLUSION: Challenges to improving food safety include, urbanization which has led to a longer food chain, underreporting of illness and difficulty in linking contaminated food to illness. Our approach can improve food safety by enabling early identification of unsafe foods which can lead to timely recall thereby limiting the health and economic impact on the public.

Comorbidity in US patients with multiple sclerosis.

OBJECTIVE: To assess the trends in the prevalence of comorbidities in US patients with multiple sclerosis (MS), and the association of demographic characteristics with the presence of comorbidities. STUDY DESIGN: A retrospective analysis was conducted from a sample of 5 million patients from the IMS Health Real World Data Adjudicated Claims - US database. METHODS: Comorbidity in patients with MS was assessed by year (2006-2014), and logistic regression models evaluated the association of age, sex, and region with select comorbidities. RESULTS: The most common comorbidities from 2006 to 2014 were hyperlipidemia and hypertension (25.9%-29.7% of patients within an individual year), followed by gastrointestinal disease (18.4%-21.2% of patients) and thyroid disease (12.9%-17.1% of patients). The proportion with a claim for hyperlipidemia increased from 2006 to 2009, was stable from 2009 to 2011, and then declined from 2011 to 2014. The proportion with a claim for hypertension generally increased from 2006 to 2013, then declined from 2013 to 2014. The proportion with a claim for gastrointestinal disease, thyroid disease, and anxiety generally increased from 2006 to 2014. Claims for comorbidities were statistically significantly more likely among older age groups (p<0.05), with the exception of anxiety and alcohol abuse, which were statistically significantly less likely among older age groups. Claims for gastrointestinal disease (OR=0.75), thyroid disease (OR=0.36), chronic lung disease (OR=0.76), arthritis (OR=0.71), anxiety (OR=0.63), and depression (OR=0.69) were statistically significantly less likely among males versus females (all p<0.05). Claims for hyperlipidemia (OR=1.39), hypertension (OR=1.25), diabetes (OR=1.31), and alcohol abuse (OR=2.41) were significantly more likely among males (p<0.05). Many comorbidity claims were statistically significantly more likely in the Northeast and South compared with the Midwest and West. CONCLUSION: This study provides select comorbidity claims estimates in US patients with MS, and thus highlights the importance of comprehensive patient care approaches.

Factors associated with early initiation of disease-modifying drug treatment in newly-diagnosed patients with multiple sclerosis.

OBJECTIVE: To examine the time to first disease-modifying drug (DMD) treatment and to identify factors associated with early DMD initiation in newly-diagnosed patients with MS. METHODS: This retrospective cohort study included newly-diagnosed patients with MS from a US administrative claims database, aged 18-65 years, with a first MS diagnosis (ICD-9-CM code: 340.xx) between January 1, 2007 and June 30, 2013 (index date), continuous eligibility for 12 months pre- and 24 months post-index, and initiated DMD treatment within 2 years. Time to first DMD within 24 months post-index was evaluated. A logistic regression model predicted earlier initiation of DMD treatment (within 60 days of MS diagnosis). RESULTS: In total, 37.4% of patients initiated DMD treatment within 2 years of MS diagnosis and were included in the primary analysis (n = 7,124). Mean (standard deviation [SD]) time from MS diagnosis to first DMD was 112.6 (148.3) days (median = 51); 30.7% received first DMD in <30 days, 55.1% in <60 days, and 18.5% not until ≥180 days after diagnosis. Logistic regression found that younger age; not living in the Northeast; diagnoses of balance disorders, numbness, and optical neuritis; the absence of musculoskeletal diagnoses; and a neurologist visit or MRI within 90 days before diagnosis were associated with DMD initiation within 60 days. CONCLUSIONS: In this population of patients initiating DMD treatment within 2 years of MS diagnosis, mean time to first DMD was 112.6 days. Identifying factors associated with delayed treatment may provide better understanding of the reasons for delay, leading to improved disease management.

An evaluation of adherence in patients with multiple sclerosis newly initiating treatment with a self-injectable or an oral disease-modifying drug.

OBJECTIVE: As the multiple sclerosis (MS) disease-modifying drug (DMD) treatment options have expanded to include oral therapies, it is important to understand whether route of administration is associated with DMD adherence. The objective of this study was to compare adherence to DMDs in patients with MS newly initiating treatment with a self-injectable versus an oral DMD. METHODS: This retrospective database study used IMS Health Real World Data Adjudicated Claims - US data between July 1, 2010 and June 30, 2014. Adherence was measured by medication possession ratio (MPR), calculated as the total number of treated days divided by the total number of days from the first treated day until the end of 12-month follow-up. A binary measure representing adherence (MPR ≥0.8) versus nonadherence (MPR <0.8) to therapy was used. Logistic regression evaluated the likelihood of adherence to index DMD type (self-injectable vs oral). Covariates included patient baseline characteristics (ie, age, sex, comorbidities) and index DMD type. RESULTS: The analysis included 7,207 self-injectable and 1,175 oral DMD-treated patients with MS. In unadjusted analyses, the proportion of patients adherent to therapy (MPR ≥0.8) did not differ significantly between the self-injectable (54.1%) and the oral DMD cohorts (53.0%; P=0.5075). After controlling for covariates, index DMD type was not a significant predictor of adherence (odds ratio [OR] 1.062; 95% confidence interval [CI]: 0.937-1.202; P=0.3473). Higher likelihood of adherence was associated with male sex (OR 1.20; 95% CI: 1.085-1.335; P=0.0005) and age groups older than 18-34 years (ORs 1.220-1.331; P<0.01). Depression was associated with a lower likelihood of adherence (OR 0.618; 95% CI: 0.511-0.747; P<0.0001). CONCLUSION: Male sex and age older than 18-34 years were significantly associated with a higher likelihood of adherence, while depression was associated with a lower likelihood of adherence. Index DMD type, stratified by the route of administration (self-injectable vs oral DMD), was not a significant predictor of DMD adherence.

Antithrombotic use and bleeding risk in patients with atrial fibrillation: findings from a multipayer analysis.

AIMS: To analyze administrative claims data from Medicaid, Medicare and commercial insurance sources to estimate stroke risk, bleeding risk, and the use of antithrombotic treatment in patients with atrial fibrillation (AF). METHODS: Included patients were aged ≥18 years with a new or existing diagnosis of AF. Outcomes were assessed over 1 year and included stroke risk (CHADS2/CHA2DS2-VASc score), bleeding risk (ATRIA score) and anticoagulant use. RESULTS: A total of 115,906 patients with AF met inclusion criteria between six databases. Among patients with high stroke risk (CHADS2 ≥2) and low bleeding risk (ATRIA 0-3), 42-82% did not receive an antithrombotic. CONCLUSION: Levels of thromboprophylaxis for high-risk AF patients in real-world data differ significantly from current medical guidelines for stroke prevention.

Economic impact of psychiatric relapse and recidivism among adults with schizophrenia recently released from incarceration: a Markov model analysis.

OBJECTIVES: To develop an economic model that estimates the cost burden of psychiatric relapse and recidivism among patients with schizophrenia recently released from incarceration from a US state government perspective. METHODS: A Markov state-transition model was developed to estimate the numbers of schizophrenia patients recently-released from incarceration who would experience psychiatric relapse and/or arrest and re-incarceration over a period of 3 years, along with corresponding costs. The model includes three health states: (1) in community, on therapy, (2) in community, off therapy, and (3) incarcerated. It is assumed that a patient's probability of psychiatric hospitalization increases with treatment discontinuation, and the probability of arrest increases with the occurrence of a prior psychiatric hospitalization. Data from the US Census and Bureau of Justice Statistics were used to estimate the model population. Published literature was used to estimate the risks of psychiatric relapse, arrest, and all cost inputs. State-specific incarceration rates and sentence length data (from the state of Florida) were applied. The impact on outcomes and costs was evaluated by varying the rates of anti-psychotic treatment following release from incarceration and the annual risk of medication discontinuation. RESULTS: Among 34,500 persons released from incarceration in the state of Florida annually, 5307 were estimated to have schizophrenia. The cumulative 3-year costs to the state government were $21,146,000 and $25,616,000 for criminal justice and psychiatric hospitalization costs, respectively ($3984 per patient criminal justice; $4827 per patient hospitalization costs). A relative 20% increase in the proportion of patients receiving antipsychotic treatment following release from incarceration decreased total cumulative costs over 3 years by $1,871,100 ($353 per patient). CONCLUSIONS: The economic impact of psychiatric relapse and recidivism among patients with schizophrenia is substantial from the state government perspective. This general model can be made state-specific by utilizing local criminal justice data sources.

Economic evaluation of linaclotide for the treatment of adult patients with irritable bowel syndrome with constipation in the United States.

OBJECTIVES: To use techniques of decision-analytic modeling to evaluate the effectiveness and costs of linaclotide vs lubiprostone in the treatment of adult patients with irritable bowel syndrome with constipation (IBS-C). METHODS: Using model inputs derived from published literature, linaclotide Phase III trial data and a physician survey, a decision-tree model was constructed. Response to therapy was defined as (1) a ≥ 14-point increase from baseline in IBS-Quality-of-Life (IBS-QoL) questionnaire overall score at week 12 or (2) one of the top two responses (moderately/significantly relieved) on a 7-point IBS symptom relief question in ≥ 2 of 3 months. Patients who do not respond to therapy are assumed to fail therapy and accrue costs associated with a treatment failure. Model time horizon is aligned with clinical trial duration of 12 weeks. Model outputs include number of responders, quality-adjusted life-years (QALYs), and total costs (including direct and indirect). Both one-way and probabilistic sensitivity analyses were conducted. RESULTS: Treatment for IBS-C with linaclotide produced more responders than lubiprostone for both response definitions (19.3% vs 13.0% and 61.8% vs 57.2% for IBS-QoL and symptom relief, respectively), lower per-patient costs ($803 vs $911 and $977 vs $1056), and higher QALYs (0.1921 vs 0.1917 and 0.1909 vs 0.1894) over the 12-week time horizon. Results were similar for most one-way sensitivity analyses. In probabilistic sensitivity analyses, the majority of simulations resulted in linaclotide having higher treatment response rates and lower per-patient costs. LIMITATIONS: There are no available head-to-head trials that compare linaclotide with lubiprostone; therefore, placebo-adjusted estimates of relative efficacy were derived for model inputs. The time horizon for this model is relatively short, as it was limited to the duration of available clinical trial data. CONCLUSIONS: Linaclotide was found to be a less costly option vs lubiprostone for the treatment of adult patients with IBS-C.

Economic impact of infections among patients with primary immunodeficiency disease receiving IVIG therapy.

PURPOSE: There are limited data on the cost of infections among patients with primary immunodeficiency disease (PIDD) in clinical practice. The purpose of this study was to assess the economic impact, from the US commercial payer perspective, of infections in a cohort of patients with PIDD who were administered intravenous immunoglobulin (IVIG) therapy. METHODS: This study used administrative claims from the MarketScan(®) Database. Patients with a PIDD diagnosis, one or more prescription(s) for IVIG therapy between January 1, 2008 and February 28, 2010, and one or more prescription(s) for IVIG at least 3 months following first IVIG prescription, were selected. The study period consisted of a 7-month window following first IVIG prescription. Study measures included infection-related medical resource use and expenditures. Adjusted infection-related hospitalization expenditures were estimated using a generalized linear model, controlling for demographics, comorbidities, and infection type. RESULTS: A total 1,742 patients with PIDD and consistent IVIG use were identified, with 490 patients (mean age 43; 58.8% female) having one or more infection(s) during the 7-month study period. Infection-related inpatient hospitalizations were the most expensive component of care (US$38,574 per hospitalized patient). In multivariate modeling, the presence of a blood infection during the hospitalization (versus [vs] no blood infection), having diabetes, and younger age (<18 vs 55-64) were associated with significant increases in infection-related hospitalization expenditures (49.3%, 55.3%, and 76.5%, respectively) (P<0.05). CONCLUSION: Health care expenditures for infections in PIDD patients receiving IVIG therapy can be substantial, particularly for inpatient care. Future evaluations assessing the incremental cost of optimizing IVIG therapy should include evaluation of the effects on infection-related medical expenditures.

Impact of atrial fibrillation on stroke-related healthcare costs.

BACKGROUND: Limited data exist on the economic implications of stroke among patients with atrial fibrillation (AF). This study assesses the impact of AF on healthcare costs associated with ischemic stroke (IS), hemorrhagic stroke (HS), or transient ischemic attack (TIA). METHODS AND RESULTS: A retrospective analysis of MarketScan claims data (2005-2011) for AF patients ≥18 years old with ≥1 inpatient claim for stroke, or ≥1 ED or inpatient claim for TIA as identified by ICD-9-CM codes who had ≥12 months continuous enrollment prior to initial stroke. Initial event- and stroke-related costs 12 months post-index were compared among patients with AF and without AF. Adjusted costs were estimated, controlling for demographics, comorbidities, anticoagulant use, and baseline resource use. Data from 23,807 AF patients and 136,649 patients without AF were analyzed. Unadjusted mean cost of the index event was $20,933 for IS, $59,054 for HS, $8616 for TIA hospitalization, and $3395 for TIA ED visit. After controlling for potential confounders, adjusted mean incremental costs (index plus 12-month post-index) for AF patients were higher than those for non-AF patients by: $4726, $7824, and $1890 for index IS, HS, TIA (identified by hospitalization), respectively, and $1700 for TIA (identified by ED) (all P<0.01). In multivariate regression analysis, AF was associated with a 20% (IS), 13% (HS), and 18% (TIA) increase in total stroke-related costs. CONCLUSION: Stroke-related care for IS, HS, and TIA is costly, especially among individuals with AF. Reducing the risk of AF-related stroke is important from both clinical and economic standpoints.