The use of administrative health care databases to identify patients with rheumatoid arthritis

Hospitalization after hydroxychloroquine initiation in patients with heart failure with preserved ejection fraction and autoimmune disease

BACKGROUND

Hydroxychloroquine (HCQ) reduces cardiovascular events among patients with autoimmune disorders and is being evaluated as a therapeutic option for populations with high-risk cardiovascular disease. However, recent studies have raised concerns about HCQ use and cardiovascular events.

OBJECTIVE

To assess the association of HCQ initiation with heart failure-related and all-cause hospitalizations among patients with heart failure and preserved ejection fraction (HFpEF).

METHODS

We conducted a cohort study of patients aged ≥18 years with diagnosed HFpEF and autoimmune disease using MarketScan Commercial and Medicare Supplemental databases (2007-2019). Patients were required to initiate HCQ after their first HFpEF diagnosis (HCQ users) or not (HCQ nonusers). For the patients in the HCQ users group, the first HCQ prescription date was assigned as the index date. Index date for the HCQ nonuser group was assigned by prescription-time distribution matching HCQ users, by utilizing the number of days from HFpEF diagnosis to the first HCQ prescription. After 1:≥3 propensity score (PS) matching, Cox proportional hazards regression models were used to compare HF-related and all-cause hospitalizations between users and nonusers.

RESULTS

After PS matching, 2229 patients (592 HCQ users and 1637 HCQ nonusers) were included. After controlling for covariates, patients who received HCQ had lower risks of HF-related hospitalization (adjusted hazard ratio, 0.44; 95% CI, 0.24-0.82) and all-cause hospitalization (adjusted hazard ratio, 0.69; 95% CI, 0.57-0.83) compared with patients not using HCQ.

CONCLUSIONS

Among patients with HFpEF and autoimmune disease, initiation of HCQ use was associated with a decreased risk of HF-related and all-cause hospitalizations.

A novel method to monitor rheumatoid arthritis prevalence using hospital and medication databases

BACKGROUND

Most estimates of rheumatoid arthritis (RA) prevalence, including all official figures in Australia and many other countries, are based on self-report. Self-report has been shown to overestimate RA, but the 'gold standard' of reviewing individual medical records is costly, time-consuming and impractical for large-scale research and population monitoring. This study provides an algorithm to estimate RA cases using administrative data that can be adjusted for use in multiple contexts to provide the first approximate RA cohort in Australia that does not rely on self-report.

METHODS

Survey data on self-reported RA and medications from 25 467 respondents of the Australian Longitudinal Study on Women's Health (ALSWH) were linked with data from the national medication reimbursement database, hospital and emergency department (ED) episodes, and Medicare Benefits codes. RA prevalence was calculated for self-reported RA, self-reported RA medications, dispensed RA medications, and hospital/ED RA presentations. Linked data were used to exclude individuals with confounding autoimmune conditions.

RESULTS

Of 25 467 survey respondents, 1367 (5·4%) women self-reported disease. Of the 26 840 women with hospital or ED presentations, 292 (1·1%) received ICD-10 codes for RA. There were 1038 (2·8%) cases by the medication database definition, and 294 cases (1·5%) by the self-reported medication definition. After excluding individuals with other rheumatic conditions, prevalence was 3·9% for self-reported RA, 1·9% based on the medication database definition and 0·5% by self-reported medication definition. This confirms the overestimation of RA based on self-reporting.

CONCLUSIONS

We provide an algorithm for identifying individuals with RA, which could be used for population studies and monitoring RA in Australia and, with adjustments, internationally. Its balance of accuracy and practicality will be useful for health service planning using relatively easily accessible input data.

Long-Term Autoimmune Inflammatory Rheumatic Outcomes of COVID-19 : A Binational Cohort Study

BACKGROUND

Some data suggest a higher incidence of diagnosis of autoimmune inflammatory rheumatic diseases (AIRDs) among patients with a history of COVID-19 compared with uninfected patients. However, these studies had methodological shortcomings.

OBJECTIVE

To investigate the effect of COVID-19 on long-term risk for incident AIRD over various follow-up periods.

DESIGN

Binational, longitudinal, propensity-matched cohort study.

SETTING

Nationwide claims-based databases in South Korea (K-COV-N cohort) and Japan (JMDC cohort).

PARTICIPANTS

10 027 506 Korean and 12 218 680 Japanese patients aged 20 years or older, including those with COVID-19 between 1 January 2020 and 31 December 2021, matched to patients with influenza infection and to uninfected control patients.

MEASUREMENTS

The primary outcome was onset of AIRD (per appropriate codes from the International Classification of Diseases, 10th Revision) 1, 6, and 12 months after COVID-19 or influenza infection or the respective matched index date of uninfected control patients.

RESULTS

Between 2020 and 2021, among the 10 027 506 Korean participants (mean age, 48.4 years [SD, 13.4]; 50.1% men), 394 274 (3.9%) and 98 596 (0.98%) had a history of COVID-19 or influenza, respectively. After propensity score matching, beyond the first 30 days after infection, patients with COVID-19 were at increased risk for incident AIRD compared with uninfected patients (adjusted hazard ratio, 1.25 [95% CI, 1.18 to 1.31]) and influenza-infected control patients (adjusted hazard ratio, 1.30 [CI, 1.02 to 1.59]). The risk for incident AIRD was higher with more severe acute COVID-19. Similar patterns were observed in the Japanese cohort.

LIMITATIONS

Referral bias due to the pandemic; residual confounding.

CONCLUSION

SARS-CoV-2 infection was associated with increased risk for incident AIRD compared with matched patients without SARS-CoV-2 infection or with influenza infection. The risk for incident AIRD was higher with greater severity of acute COVID-19.

PRIMARY FUNDING SOURCE

National Research Foundation of Korea.

Real-world persistence of initial targeted therapy strategy in monotherapy versus combination therapy in patients with chronic inflammatory arthritis

OBJECTIVE

The persistence of biologic (b) and targeted synthetic (ts) disease-modifying antirheumatic drugs(DMARDs) in monotherapy versus in combination with conventional synthetic (cs) DMARDs is still a controversial topic in rheumatic diseases. To clarify this issue, the retention of the initial treatment strategy of b/tsDMARD in combination with csDMARD versus monotherapy in rheumatoid arthritis (RA), psoriatic arthritis (PsA) and ankylosing spondylitis (AS) patients under real-life conditions was evaluated. Factors associated with maintenance of the initial strategy were analysed.

METHODS

Nested cohort study within the Spanish BIOBADASER III registry. Bivariate comparisons and multivariate Cox proportional hazards models were used for the analyses.

RESULTS

A total of 2521 patients were included in the study. In the multivariate model, the initial strategy of combination therapy was associated with shorter persistence in patients with RA (hazard ratio [HR] 1.58;95% confidence interval [CI] 1.00-2.50; p = .049), PsA (HR 2.48; 95% CI 1.65-3.72) and AS (HR 16.77; 95% CI 7.37-38.16; p < .001), regardless of sex, time of disease progression, baseline disease activity, glucocorticoid use or type of b/tsDMARD. Overall, the combination strategy was associated with an increased incidence of adverse events (incidence rate ratio [IRR] 1.13; 95% CI 1.05-1.21).

CONCLUSIONS

In this real-life study, the strategy of combining a b/tsDMARD with a csDMARD is associated with lower persistence and worse safety profile compared to monotherapy in RA and especially in PsA and AS, suggesting that combination therapy should be rethought as first choice in RA patients, but especially in PsA and AS patients.

CD19-targeted chimeric antigen receptor T-cell therapy in patients with concurrent B-cell Non-Hodgkin lymphoma and rheumatic autoimmune diseases: a propensity score matching study

Rheumatic autoimmune diseases not only involve the production of autoantibodies but also demonstrate T-cell dysfunction. In patients with concurrent B-cell non-Hodgkin lymphoma (NHL) and rheumatic autoimmune diseases, the safety and efficacy of CD19-targeted chimeric antigen receptor (CAR) T-cell therapy are unknown. Using an aggregated electronic health record database, patients with rheumatic autoimmune diseases (auto group) were compared to propensity score-matched patients without rheumatic autoimmune diseases (non-auto group). From 1/2019 to 1/2023, 58 (4.3%) of 1,363 patients who received CD19-targeted CAR T-cell therapy had concurrent rheumatic autoimmune diseases. Both groups had similar incidence, severity, and management of cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). Moreover, the two groups had similar time-to-next treatment or death (hazard ratio [HR] 0.97, 95% confidence interval [CI] 0.60 to 1.59, log-rank p = 0.91) and overall survival (HR 0.90, 95%CI 0.46 to 1.78, p = 0.76). Following CAR T-cell infusion, patients with rheumatic autoimmune diseases achieved decreased inflammatory markers, seronegative conversion of autoantibodies, as well as reduced use of steroids and disease-modifying anti-rheumatic drugs. In conclusion, the safety and efficacy of CAR T-cell therapy were not affected in patients with rheumatic autoimmune diseases. Moreover, they achieved better biochemical control of underlying rheumatic diseases.

Discrepancies in ICD-9/ICD-10-based codes used to identify three common diseases in cancer patients in real-world settings and their implications for disease classification in breast cancer patients and patients without cancer: a literature review and descriptive study

Background

International Classification of Diseases, Ninth/Tenth revisions, clinical modification (ICD-9-CM, ICD-10-CM) are frequently used in the U.S. by health insurers and disease registries, and are often recorded in electronic medical records. Due to their widespread use, ICD-based codes are a valuable source of data for epidemiology studies, but there are challenges related to their accuracy and reliability. This study aims to 1) identify ICD-9/ICD-10-based codes reported in literature/web sources to identify three common diseases in elderly patients with cancer (anemia, hypertension, arthritis), 2) compare codes identified in the literature/web search to SEER-Medicare's 27 CCW Chronic Conditions Algorithm ("gold-standard") to determine their discordance, and 3) determine sensitivity of the literature/web search codes compared to the gold standard.

Methods

A literature search was performed (Embase, Medline) to find sources reporting ICD codes for at least one disease of interest. Articles were screened in two levels (title/abstract; full text). Analysis was performed in SAS Version 9.4.

Results

Of 106 references identified, 29 were included that reported 884 codes (155 anemia, 80 hypertension, 649 arthritis). Overall discordance between the gold standard and literature/web search code list was 32.9% (22.2% for ICD-9; 35.7% for ICD-10). The gold standard contained codes not found in literature/web sources, including codes for hypertensive retinopathy/encephalopathy, Page Kidney, spondylosis/spondylitis, juvenile arthritis, thalassemia, sickle cell disorder, autoimmune anemias, and erythroblastopenia. Among a cohort of non-cancer patients (N=684,376), the gold standard identified an additional 129 patients with anemia, 33,683 with arthritis, and 510 with hypertension compared to the literature/web search. Among a cohort of breast cancer patients (N=303,103), the gold standard identified an additional 59 patients with anemia, 10,993 with arthritis, and 163 with hypertension. Sensitivity of the literature/web search code list was 91.38-99.96% for non-cancer patients, and 93.01-99.96% for breast cancer patients.

Conclusion

Discrepancies in codes used to identify three common diseases resulted in variable differences in disease classification. In all cases, the gold standard captured patients missed using the literature/web search codes. Researchers should use standardized, validated coding algorithms when available to increase consistency in research and reduce risk of misclassification, which can significantly alter the findings of a study.

Association between parental autoimmune disease and childhood atopic dermatitis varied by sex: a nationwide case-control study

Atopic dermatitis (AD) is a common inflammatory skin disorder induced by dysfunction of immune suppression sharing similar pathogenesis to autoimmune diseases. To explore the association between autoimmune diseases and AD in children, we linked the birth data from National Birth Registry with National Health Insurance Research Database. There were 1,174,941 children obtained from 2006 to 2012 birth cohort. A total of 312,329 children diagnosed with AD before 5 years old were compared to 862,612 children without AD in the control group. Conditional logistic regression was utilized to calculate adjusted odds ratio (OR) and Bonferroni-corrected confidence interval (CI) for overall significance level of 0.05. In 2006-2012 birth cohort, the prevalence rate of AD was 26.6% (95% CI 26.5, 26.7) before 5 years of age. Having parental autoimmune disease (including rheumatoid arthritis, systemic lupus erythematosus, Sjogren's syndrome, ankylosing spondylitis, and psoriasis) was associated with a significant higher risk of children AD development. The other associated factors were maternal obstetric complications (including gestational diabetes mellitus and cervical incompetence), parental systemic diseases (including anemia, hypertension, diabetes mellitus, chronic obstructive pulmonary disease, hyperthyroidism, and obstructive sleep apnea), and parental allergic disease (including asthma and AD). The subgroup analysis showed similar results between children's sexes. Moreover, maternal autoimmune disease had higher impact on the risk of developing AD in the child compared with paternal autoimmune disease. In conclusion, parental autoimmune diseases were found to be related to their children's AD before 5 years old.

The prevalence of rheumatoid arthritis in Western Australia

BACKGROUND

Rheumatoid arthritis (RA) is the most common form of autoimmune arthritis, but the prevalence in Australia is unknown. We estimated RA period prevalence and identified factors associated with frequent RA hospitalisations, using linked administrative health and state-specific Australian Pharmaceutical Benefits Scheme (PBS) datasets in Western Australia (WA) from 1995 to 2014.

METHODS

This was a longitudinal population-based cohort study using two independent datasets to identify prevalent RA patients. RA prevalence was calculated per 1000 hospital separations and biological therapy users. RA patients were identified in the WA linked health dataset using ICD codes 714.0-714.9 and M05.00-M06.99. Dispensing data on biological therapy for RA were obtained from PBS records and converted to defined daily doses /1000 population/day. Multivariable logistic regression was used to analyse factors associated with frequent RA hospitalisations (> 2/year), controlling for sex, age, and geographic locations. Potential interactions were assessed using logistic regression in a stepwise approach.

RESULTS

A total of 17,125 RA patients had 50,353 hospital separations between 1995 and 2014, averaging three hospitalisations per patient over 20 years. The RA period prevalence was 3.4 per 1000 separations (0.34%; 95% CI 0.33-0.34), while the RA period prevalence based on biological therapy use was 0.36% (95% CI 0.35-0.37). The corrected RA prevalence based on biological therapy usage was 0.36% (95% CI 0.35-0.37) for the 2005-2009 and increased to 0.72% (95% CI 0.70-0.74) in 2010-2014 period. Associated factors for frequent RA hospitalisations were being female [1.21 (95% CI 1.15-1.26)], aged 60-69 years [4.45 (95% CI 3.74-5.30)], living in rural areas [1.12 (95% CI 1.02-1.24)]. The odd ratio of interaction between these associated factors was 1.34 (95% CI 1.16-1.55).

CONCLUSION

The minimal prevalence of RA in Western Australia is 0.34-0.36%, which falls within the literature range. Older female RA patients in rural were more likely to be hospitalised, suggesting unmet primary care for needs.

PheValuator 2.0: Methodological improvements for the PheValuator approach to semi-automated phenotype algorithm evaluation

PURPOSE

Phenotype algorithms are central to performing analyses using observational data. These algorithms translate the clinical idea of a health condition into an executable set of rules allowing for queries of data elements from a database. PheValuator, a software package in the Observational Health Data Sciences and Informatics (OHDSI) tool stack, provides a method to assess the performance characteristics of these algorithms, namely, sensitivity, specificity, and positive and negative predictive value. It uses machine learning to develop predictive models for determining a probabilistic gold standard of subjects for assessment of cases and non-cases of health conditions. PheValuator was developed to complement or even replace the traditional approach of algorithm validation, i.e., by expert assessment of subject records through chart review. Results in our first PheValuator paper suggest a systematic underestimation of the PPV compared to previous results using chart review. In this paper we evaluate modifications made to the method designed to improve its performance.

METHODS

The major changes to PheValuator included allowing all diagnostic conditions, clinical observations, drug prescriptions, and laboratory measurements to be included as predictors within the modeling process whereas in the prior version there were significant restrictions on the included predictors. We also have allowed for the inclusion of the temporal relationships of the predictors in the model. To evaluate the performance of the new method, we compared the results from the new and original methods against results found from the literature using traditional validation of algorithms for 19 phenotypes. We performed these tests using data from five commercial databases.

RESULTS

In the assessment aggregating all phenotype algorithms, the median difference between the PheValuator estimate and the gold standard estimate for PPV was reduced from -21 (IQR -34, -3) in Version 1.0 to 4 (IQR -3, 15) using Version 2.0. We found a median difference in specificity of 3 (IQR 1, 4.25) for Version 1.0 and 3 (IQR 1, 4) for Version 2.0. The median difference between the two versions of PheValuator and the gold standard for estimates of sensitivity was reduced from -39 (-51, -20) to -16 (-34, -6).

CONCLUSION

PheValuator 2.0 produces estimates for the performance characteristics for phenotype algorithms that are significantly closer to estimates from traditional validation through chart review compared to version 1.0. With this tool in researcher's toolkits, methods, such as quantitative bias analysis, may now be used to improve the reliability and reproducibility of research studies using observational data.

Systematic review: development of a consensus code set to identify cirrhosis in electronic health records

BACKGROUND

Electronic health records (EHRs) collate longitudinal data that can be used to facilitate large-scale research in patients with cirrhosis. However, there is no consensus code set to define the presence of cirrhosis in EHR. This systematic review aims to evaluate the validity of diagnostic coding in cirrhosis and to synthesise a comprehensive set of ICD-10 codes for future EHR research.

METHOD

MEDLINE and EMBASE databases were searched for studies that used EHR to identify cirrhosis and cirrhosis-related complications. Validated code sets were summarised, and the performance characteristics were extracted. Citation analysis was done to inform development of a consensus code set. This was then validated in a cohort of patients.

RESULTS

One thousand six hundred twenty-six records were screened, and 18 studies were identified. The positive predictive value (PPV) was the most frequently reported statistical estimate and was ≥80% in 17/18 studies. Citation analyses showed continued variation in those used in contemporary research practice. Nine codes were identified as those most frequently used in the literature and these formed the consensus code set. This was validated in diverse patient populations from Europe and North America and showed high PPV (83%-89%) and greater sensitivity for the identification of cirrhosis than the most often used code set in the recent literature.

CONCLUSION

There is variation in code sets used to identify cirrhosis in contemporary research practice. A consensus set has been developed and validated, showing improved performance, and is proposed to align EHR study designs in cirrhosis to facilitate international collaboration and comparisons.

Trends in hospitalizations for vertebral compression fracture in ankylosing spondylitis: data from the National Inpatient Sample 2000-2014

Ankylosing spondylitis (AS) patients are at increased risk of vertebral compression fractures (VCF). Our objective was to examine the yearly trend of VCF hospitalizations in AS patients as compared to rheumatoid arthritis (RA) and the general population. National Inpatient Sample (NIS) database (2000-2014) was used to identify adult (≥ 18 years) hospitalizations, based on validated ICD-9 diagnosis codes. The rate of VCF hospitalizations, as a primary diagnosis, was assessed in three mutually exclusive groups: AS, RA, and the general population. The prevalence of VCF hospitalization was highest in AS (2.70%), compared to 0.77% in RA and 0.35% in the general population. Over the 15-year period, VCF hospitalization in AS was noted to have an increasing trend (Annual Percent Change (APC) = 4.73, p < 0.05) in contrast to the stable trend in the general population (APC = 0.34, p = NS) and a declining trend in RA (APC -3.61, p < 0.05). VCF related to AS was also associated with a longer hospital stay as compared to the general population (8.1 days vs. 5.1 days, p < 0.05) and higher inpatient mortality (3.4% vs. 1.0%, p < 0.05). A higher rate of VCF hospitalization along with an increasing trend was noted in AS as compared to RA and compared to the general population. Better screening approaches and treatment strategies for AS patients with VCF risk are urgently needed to reduce hospitalizations and related complications. Key Points • An increasing trend of VCF hospitalization was noted in AS, in contrast to a declining trend in RA and a stable trend in the general population. • VCF in AS was associated with longer hospital stay and higher inpatient mortality than in RA and the general population.

Validity of Algorithms for Identification of Individuals Suffering from Chronic Noncancer Pain in Administrative Databases: A Systematic Review

BACKGROUND

Secondary analysis of health administrative databases is indispensable to enriching our understanding of health trajectories, health care utilization, and real-world risks and benefits of drugs among large populations.

OBJECTIVES

This systematic review aimed at assessing evidence about the validity of algorithms for the identification of individuals suffering from nonarthritic chronic noncancer pain (CNCP) in administrative databases.

METHODS

Studies reporting measures of diagnostic accuracy of such algorithms and published in English or French were searched in the Medline, Embase, CINAHL, AgeLine, PsycINFO, and Abstracts in Social Gerontology electronic databases without any dates of coverage restrictions up to March 1, 2018. Reference lists of included studies were also screened for additional publications.

RESULTS

Only six studies focused on commonly studied CNCP conditions and were included in the review. Some algorithms showed a ≥60% combination of sensitivity and specificity values (back pain disorders in general, fibromyalgia, low back pain, migraine, neck/back problems studied together). Only algorithms designed to identify fibromyalgia cases reached a ≥80% combination (without replication of findings in other studies/databases).

CONCLUSIONS

In summary, the present investigation informs us about the limited amount of literature available to guide and support the use of administrative databases as valid sources of data for research on CNCP. Considering the added value of such data sources, the important research gaps identified in this innovative review provide important directions for future research. The review protocol was registered with PROSPERO (CRD42018086402).

Prevalence of rheumatoid arthritis in Edmonton and Northern Alberta

OBJECTIVE

The purpose of this study was to compare and contrast the prevalence of rheumatoid arthritis in Northern Alberta estimated by health administrative data and data from a rheumatologist-based prescription database.

METHODS

The study was performed using administrative health data from the province of Alberta through the local health authority. The cases and population identified in the database were reported from the year 2016. Rheumatology prescribing data was accessed through the Physician Learning Program and based on Alberta health billing data of actively practicing rheumatologists between the years 2012 and 2016. Ethics was provided by the Conjoint Health Research Ethics Boards at the University of Calgary (REB 13-0459).

RESULTS

The total population of the area examined was determined to be 2,086,181. The administrative health database identified 42,354 cases of RA based on their case definition with a prevalence of 2.08%. Based on rheumatologist diagnosis and prescribing data, the number of cases identified was 11,273 cases of RA with a prevalence of 0.542%. The average percentage of identified RA patients being seen by a rheumatologist was determined to be 26.7% with the range of 19.8 to 39.9%.

CONCLUSION

In conclusion, this study compares and contrasts the prevalence of rheumatoid arthritis reported by administrative data versus identification by specialists. Our study again illustrates that accuracy of case definitions when studying chronic conditions such as rheumatoid arthritis is paramount. The results also suggest a lack of access to rheumatologist services in Northern Alberta and reiterate the need for ongoing recruitment of new rheumatologists as has been highlighted previously. Key Points • The main contribution of this paper is to compare and contrast the prevalence of rheumatoid arthritis as reported by administrative data versus identification by specialists. • Our study also shows the distribution of rheumatoid arthritis in a large geographical area and illustrates a lack of access to subspecialty care in certain regions.

Use of Disease-modifying Antirheumatic Drugs, Biologics, and Corticosteroids in Older Patients With Rheumatoid Arthritis Over 20 Years

OBJECTIVE

To examine changes in prescribing patterns, especially the use of corticosteroids (CS), in patients with rheumatoid arthritis (RA) over 2 decades.

METHODS

This was a secondary analysis of health administrative data using a previously validated dataset and case definition for RA. Cases were matched 1:4 by age and sex to controls within a population of approximately 1 million inhabitants with access to universal health care. Longitudinal data for incident and prevalent RA cases were studied between 1997 and 2017.

RESULTS

There were 8240 RA cases (all ≥ 65 yrs) with a mean (SD) age 72.2 (7.5) years and 70.6% were female. Over 20 years, annual utilization of coxibs in prevalent RA cases fell with a concomitant increase in disease-modifying antirheumatic drugs (DMARDs) and biologics. Over the same period, CS use was largely unchanged. Approximately one-third of patients had at least 1 annual prescription for CS, most frequently prednisone. The mean annual dose showed a modest reduction and the duration of utilization in each year shortened. Rheumatologists prescribed CS less frequently and in lower doses than other physician groups. For incident RA cases, there was a significant fall in annual prescribed dose of prednisone by rheumatologists over time.

CONCLUSION

In older adults with RA, the utilization of DMARDs and biologics has increased over the past 20 years. However, the use of CS has persisted. Renewed efforts are required to minimize their use in the long-term pharmacological management of RA.

Prevalence of Rheumatoid Arthritis and Drug Dispensing Patterns Among Medicaid and Medicaid-Medicare Dually Eligible Beneficiaries in Puerto Rico

OBJECTIVE

To estimate the prevalence of rheumatoid arthritis (RA) in Puerto Rico, to describe disease-modifying antirheumatic drug (DMARD) dispensing patterns by prescriber specialty, and to illustrate the impact of RA case definition on the estimated prevalence.

METHODS

This study estimated the prevalence of RA in Puerto Rico during 2016 among Medicaid and Medicaid-Medicare dually eligible beneficiaries of the Mi Salud health care plan, a federally funded health insurance program. DMARD dispensing and cost patterns were described and stratified by provider specialty. A sensitivity analysis was conducted to evaluate the effect of RA case definition on estimated prevalence.

RESULTS

The prevalence of RA in 2016 was estimated to be 2 cases per 1,000 beneficiaries, with 3 per 1,000 beneficiaries among females, 4.5 times that of males. In total, 44% of beneficiaries received conventional synthetic DMARDs (csDMARDs) only, 32% received biologic or targeted synthetic DMARDs (b/tsDMARDs) only, and 24% received a combination of csDMARDs and b/tsDMARDs. Rheumatologists and a combination of specialties accounted for the highest median number of dispensed DMARDs, with 14 each. A sensitivity analysis revealed that when RA cases with ≥3 medical claims were restricted to having ≥1 DMARD claim, the estimated prevalence changed from 6 to 3 cases per 1,000 beneficiaries.

CONCLUSION

The prevalence of RA in Puerto Rico in this study is lower than reported in the mainland US, possibly due to more stringent criteria to define RA. DMARD dispensing and cost patterns are similar to those found in other studies. Claims algorithms that identify RA have higher validity when pharmacy data is included.

Treatment Patterns of Newly Diagnosed Rheumatoid Arthritis Patients from a Commercially Insured Population

INTRODUCTION

To describe treatment patterns in newly diagnosed rheumatoid arthritis (RA) patients in a large, nationally representative managed-care database.

METHODS

Newly diagnosed RA patients were identified from 07/01/2006-08/31/2014. Patients had ≥ 1 RA diagnosis by a rheumatologist, or ≥ 2 non-rheumatologist RA diagnoses ≥ 30 days apart, or RA diagnosis followed by a disease-modifying antirheumatic drug (DMARD) prescription fill within 1 year. Patients were ≥ 18 years old at index (earliest date fulfilling diagnostic criteria) and had ≥ 6 and 12 months of pre- and post-index health plan enrollment, respectively. Patterns of DMARD treatment, including conventional synthetic DMARDs (csDMARD), tumor necrosis factor inhibitors (TNFi), non-TNFi, and Janus kinase inhibitors (JAKi), were captured during follow-up.

RESULTS

Of the 63,101 RA patients identified, 73% were female; mean age was 57 years. During an average of 3.5 ± 2.1 years of follow-up, 45% of patients never received a DMARD, 52% received a csDMARD (94 ± 298 mean ± SD days from index), 16% a TNFi (315 ± 448 days), 4% a non-TNFi (757 ± 660 days), and < 1% a JAKi. Among DMARD recipients, the most common treatment patterns were: receiving csDMARDs only (68%), adding a TNFi as second-line therapy after initiation of a csDMARD (12%), and receiving only a TNFi (6%) during follow-up. Among those not on DMARDs, the all-cause usage of an opioid was 56% and 19% had chronic opioid use (≥ 180 days supplied).

CONCLUSIONS

Despite American College of Rheumatology recommendations for DMARD treatment of RA, nearly half of newly diagnosed RA patients received no DMARD therapy during follow-up. These data identify a treatment gap in RA management.

FUNDING

Eli Lilly & Company.

A Longitudinal Study of Ambulatory Physician Encounters, Emergency Room Visits, and Hospitalizations by Patients with Rheumatoid Arthritis: A 13-year Population Health Study

Objective.

To determine total physician encounters, emergency room (ER) visits, and hospitalizations in an incident cohort of rheumatoid arthritis (RA) cases and matched control patients over 13 years.

Methods.

A retrospective cohort study was performed using administrative healthcare data from about 1 million people with access to universal healthcare. Using the International Classification of Diseases, 9th ed (ICD-9) and ICD-10 diagnostic codes, 7 RA case definitions were used. Each case was matched by age and sex to 4 randomly selected controls. Data included physician billings, ER visits, and hospital discharges over 13 years.

Results.

The number of incident RA cases varied from 3497 to 27,694, depending on the case definition. The mean age varied from 54.3 to 65.0 years, and the proportion of women from 67.8% to 71.3%. The number of physician encounters by patients with RA was significantly higher than by controls. It was highest in the index year and declined promptly thereafter for all case definitions and by 12.2%–46.8% after 10 years. Encounters with subspecialty physicians fell by 61% (rheumatologists) and 34% (internal medicine). In contrast, clinical encounters with family physicians and other physicians fell by only 9%. Visits to the ER and hospital admissions were also significantly higher in RA cases, particularly early in the disease, and fell significantly over the followup.

Conclusion.

In patients with RA, healthcare use is highest in the first year following the diagnosis, which is also the time of maximal involvement by rheumatologists. Use declines over time, and encounters with patients’ family physicians predominate over other physician groups.

Prevalence of rheumatoid arthritis in the United States adult population in healthcare claims databases, 2004-2014

This study aimed to determine the prevalence of rheumatoid arthritis in the United States (US) adult insured population from 2004 to 2014. This was an observational, retrospective, cross-sectional study based on US administrative health insurance claims databases (Truven Health MarketScan^® Research database and IMS PharMetrics Plus database). Trends in RA prevalence focusing on the 10-year period covering January 1, 2004-December 31, 2014 were analyzed using a validated algorithm for the identification of RA. Prevalence rates in the databases were determined and age- and gender-adjusted rates were projected to the US population in 2014. Analysis of data from the two databases indicated that the RA prevalence rate in commercially insured adult US population ranged from 0.41 to 0.54% from 2004 to 2014. The prevalence varied substantially by gender and age in each year and increased gradually across the years for most subgroups. In 2014, out of 31,316,902 adult patients with continuous enrollment in the Truven Health MarketScan^® Research database, 157,634 (0.50%) patients met our criteria for RA. Similarly, out of 35,083,356 adult patients in the IMS PharMetrics Plus database, 139,300 (0.50%) patients met our criteria for RA. In 2014, the overall age-adjusted prevalence of RA ranged from 0.53 to 0.55% (0.29-0.31% for males and 0.73-0.78% for females). The prevalence of RA in the US appeared to increase during the period from 2004 to 2014, affecting a conservative estimate of 1.28-1.36 million adults in 2014.