Diagnosis Code For Rheumatoid Arthritis Research Articles

Changes in Characteristics of Patients Initiating and Discontinuing Advanced Therapies for Rheumatoid Arthritis Following the Release of Safety Data.

The objective of this study was to determine the impact of emerging safety data on practice patterns by describing the characteristics of patients initiating and discontinuing advanced therapies for rheumatoid arthritis (RA) before and after January 2021. This cohort study evaluated US veterans with RA between April 2019 and September 2022. This period was divided into two 664-day periods before and after January 2021. Eligible patients had ≥1 diagnosis code for RA and initiated a tumor necrosis factor inhibitor (TNFi), non-TNFi biologic, or JAK inhibitor (JAKi). We tested for interaction within regression models to determine whether changes in patient characteristics for tofacitinib recipients were different from changes observed for other therapies. We also evaluated factors associated with therapy discontinuation in Cox models adjusted for age, sex, and duration on therapy, including assessment for effect modification. When comparing patients with RA initiating tofacitinib before (n=2,111) with those initiating tofacitinib after (n=1,664) January 2021, there was a decrease in mean age (64.1 vs 63.0 years) and in the proportion with cardiovascular comorbidities (all P < 0.01). These changes were significantly different from those observed for patients initiating TNFi or non-TNFi biologics. Among active advanced therapy recipients, the likelihood of discontinuation was higher for tofacitinib than TNFi (hazard ratio 1.18, 95% confidence interval 1.10-1.26, P < 0.001). The higher rate of tofacitinib discontinuation was more pronounced in the presence of cardiovascular comorbidities (P < 0.05). Recent safety data significantly affected prescribing practices for advanced therapies, with a reduction in JAKi initiation and an increase in JAKi discontinuation among older patients and those at high cardiovascular risk.

Comparison of Rheumatoid Arthritis Information Recorded in UK CPRD Aurum and CPRD GOLD Databases (Companion Paper 3).

To report distribution of codes associated with a rheumatoid arthritis (RA) diagnosis recorded in Clinical Practice Research Datalink (CPRD) Aurum compared to the previously validated CPRD GOLD database as a critical step toward making decisions about CPRD Aurum's suitability for medical research. We analyzed the distribution of codes for RA diagnoses, labs, and treatments in the new CPRD Aurum database, compared to the CPRD GOLD database by selecting relevant indicators of RA diagnosis, treatment, and clinical care. We included all patients in England in CPRD Aurum and CPRD GOLD with an incident diagnosis code for RA on or after 1 January 2005 and at least two years recorded data before first RA diagnosis. We found 53,083 and 18,167 patients with a new diagnosis code for RA in CPRD Aurum and CPRD GOLD, respectively. In both databases approximately 67% were female with similar mean ages at first diagnosis. There were few differences in RA-related recording patterns between the two data sources. Before first RA diagnosis, CPRD Aurum patients had more RA-specific labs and other supporting clinical codes. After diagnosis, CPRD Aurum patients had more RA diagnoses coded and more often had 10+ general RA labs than patients in CPRD GOLD. More CPRD GOLD patients had 10+ prescriptions for conventional disease-modifying antirheumatic drugs (cDMARD) compared to CPRD Aurum. Otherwise, the distribution of drugs used to treat RA was similar between databases. The standardized incidence of RA was similar between databases. Overall, among patients with a diagnosis code for RA, recording of diagnoses, prescription drugs, and labs were similar between CPRD Aurum and CPRD GOLD. Slight differences were found for a few variables, but overall, we found consistency between the databases. In addition, standardized incidence of RA was similar between databases.

Changes in Patterns of Use of Advanced Therapies Following Emerging Data About Adverse Events in Patients With Rheumatoid Arthritis From the Veterans Affairs Health System.

To determine whether prescribing practices for Janus kinase inhibitors (JAKi), tumor necrosis factor inhibitors (TNFi), and non-TNFi biologic agents changed after the results of the Oral Rheumatoid Arthritis Trial (ORAL) Surveillance trial were released in January 2021. This is a retrospective study in adult patients with rheumatoid arthritis (RA) receiving advanced therapies within the Veterans Affairs Health System from January 2012 through September 2022. Eligible patients were required to have at least one diagnosis code for RA and to have received a biologic disease-modifying antirheumatic drug or JAKi. Treatment courses were defined from pharmacy dispensing data and the number of new courses of each advanced therapy was quantified over time. We assessed changes in the use of each therapy before and after the release of safety data (January 2021). A total of 88,253 individual drug courses (in 34,656 unique patients) were included in the study. There was a consistent increase in the number and proportion of new courses of JAKi leading up to January 2021, which was followed by a significant net decrease in JAKi use through September 2022. There was significantly less tofacitinib use after the release of safety data, with a significant difference in the slope of change in use with time. In contrast, whereas TNFi use declined leading up to 2021, its use significantly increased after January 2021. Changes in prescribing in response to new evidence emphasize the impact that safety trials have on prescribing practices. Ongoing study in this area, with attention to specific patient characteristics and risk profiles, will help characterize these changes in practice.

Comparing cardiovascular risk of patients with rheumatoid arthritis within the Social Security Disability Insurance with those commercially insured

ObjectiveTo compare cardiovascular disease (CVD) rates in rheumatoid arthritis (RA) beneficiaries of the Social Security Disability Insurance (SSDI) with commercially insured RA patients.MethodWe created three cohorts of RA patients aged < 65 years for SSDI and three for Marketscan using claims data from 2006 to 2016. The cohort definitions were as follows: (1) cohort 1: ≥ 2 diagnosis codes for RA occurring 7–365 days apart with ≥ 1 diagnosis code from a rheumatologist; (2) cohort 2: ≥ 1 diagnosis code for RA from a rheumatologist and a disease-modifying antirheumatic drugs (DMARDS); and (3) cohort 3: cohort 2, plus initiation of a new biologic/tofacitinib. We used Cox regression to determine the CVD risk comparing SSDI vs. Marketscan. Models were sequentially adjusted for age and sex (model 1); model 1 + diabetes, smoking, and high CVD risk (model 2); and model 2 + dual eligible (Medicare and Medicaid), subsidy, and state buy in (model 3).ResultsThere were 380,336 RA patients, mean age 53.3 (SD 8.1) years, 21–24% male. Prevalence of comorbidities was higher in SSDI vs. Marketscan. SSDI RA patients in cohort 2 (model 3) had higher CVD risk (HR 1.23 (1.14–1.33). In cohort 3 (model 3), CVD risk was not statistically significantly different between SSDI and Marketscan (HR 0.89 (0.69–1.15).ConclusionRA patient beneficiaries of the SSDI had higher risk for CVD events than those employed. The differences in CVD events between SSDI and Marketscan were partially attributable to differences in CVD risk factors.

Evaluating Quality of Care for Rheumatoid Arthritis for the Population of Alberta Using System-level Performance Measures

We evaluated 4 national rheumatoid arthritis (RA) system-level performance measures (PM) in Alberta, Canada. Incident and prevalent RA cases ≥ 16 years of age since 2002 were identified using a validated case definition applied in provincial administrative data. Performance was ascertained through analysis of health data between fiscal years 2012/13-2015/16. Measures evaluated were as follows: proportion of incident RA cases with a rheumatologist visit within 1 year of first RA diagnosis code (PM1); proportion of prevalent RA patients who were dispensed a disease-modifying antirheumatic drug (DMARD) annually (PM2); time from first visit with an RA code to DMARD dispensation and proportion of incident cases where the 14-day benchmark for dispensation was met (PM3); and proportion of patients seen in annual follow-up (PM4). There were 31,566 prevalent and 2730 incident RA cases (2012/13). Over the analysis period, the proportion of patients seen by a rheumatologist within 1 year of onset (PM1) increased from 55% to 63%; however, the proportion of RA patients dispensed DMARD annually (PM2) remained low at 43%. While the median time to DMARD from first visit date in people who received DMARD improved over time from 39 days to 28 days, only 38-41% of patients received treatment within the 14-day benchmark (PM3). The percentage of patients seen in yearly follow-up (PM4) varied between 73-80%. The existing Alberta healthcare system for RA is suboptimal, indicating barriers to accessing specialty care and treatment. Our results inform quality improvement initiatives required within the province to meet national standards of care.

Investigating the impact of disease and health record duration on the eMERGE algorithm for rheumatoid arthritis.

The study sought to determine the dependence of the Electronic Medical Records and Genomics (eMERGE) rheumatoid arthritis (RA) algorithm on both RA and electronic health record (EHR) duration. Using a population-based cohort from the Mayo Clinic Biobank, we identified 497 patients with at least 1 RA diagnosis code. RA case status was manually determined using validated criteria for RA. RA duration was defined as time from first RA code to the index date of biobank enrollment. To simulate EHR duration, various years of EHR lookback were applied, starting at the index date and going backward. Model performance was determined by sensitivity, specificity, positive predictive value, negative predictive value, and area under the curve (AUC). The eMERGE algorithm performed well in this cohort, with overall sensitivity 53%, specificity 99%, positive predictive value 97%, negative predictive value 74%, and AUC 76%. Among patients with RA duration <2 years, sensitivity and AUC were only 9% and 54%, respectively, but increased to 71% and 85% among patients with RA duration >10 years. Longer EHR lookback also improved model performance up to a threshold of 10 years, in which sensitivity reached 52% and AUC 75%. However, optimal EHR lookback varied by RA duration; an EHR lookback of 3 years was best able to identify recently diagnosed RA cases. eMERGE algorithm performance improves with longer RA duration as well as EHR duration up to 10 years, though shorter EHR lookback can improve identification of recently diagnosed RA cases.

Patterns of Tumor Necrosis Factor Inhibitor (TNFi) Biosimilar Use Across United States Rheumatology Practices.

ObjectiveIt is unclear if biosimilars of biologics for inflammatory arthritis are realizing their promise to increase competition and improve accessibility. This study evaluates biosimilar tumor necrosis factor inhibitor (TNFi) utilization across rheumatology practices in the United States and compares whether patients initiating biosimilars remain on these treatments at least as long as new initiators of bio‐originators.MethodsWe identified a cohort of patients initiating a TNFi biosimilar between January 2017 and September 2018 from an electronic health record registry containing data from 218 rheumatology practices and over 1 million rheumatology patients in the United States. We also identified a cohort of patients who initiated the bio‐originator TNFi during the same period. We calculated the proportion of biosimilar prescriptions compared with other TNFi's and compared persistence on these therapies, adjusting for age, sex, diagnoses codes, and insurance type.ResultsWe identified 909 patients prescribed the biosimilar infliximab‐dyyb, the only biosimilar prescribed, and 4413 patients with a new prescription for the bio‐originator infliximab. Biosimilar patients tended to be older, have a diagnosis code for rheumatoid arthritis, and covered by Medicare insurance. Over the study period, biosimilar prescriptions reached a maximum of 3.5% of all TNFi prescriptions. Patients persisted on the biosimilar at least as long as the bio‐originator infliximab (hazard ratio [HR] 0.83, P = 0.07).ConclusionThe uptake of biosimilars in the United States remains low despite persistence on infliximab‐dyyb being similar to the infliximab bio‐originator. These results add to clinical studies that should provide greater confidence to patients and physicians regarding biosimilar use.

PSY17 ASSESSING THE ECONOMIC BURDEN AND PREDICTORS OF HOSPITALIZATION AMONG US VETERAN PATIENTS WITH RHEUMATOID ARTHRITIS: A RETROSPECTIVE CASE-CONTROL STUDY

Rheumatoid arthritis (RA) is highly prevalent among US veterans. This study assessed health care costs and predictors of hospitalization among patients with RA in the US Veterans Health Administration (VHA) population (01APR2013-31MAR2018). Adult patients with ≥1 inpatient diagnosis code for RA (International Classification of Disease, 9th/10th Revision, Clinical Modification [ICD-9-CM] codes 714.0-714.4, 714.8, 714.9; ICD-10-CM: M05, M06, M08, M12) were identified (01APR2013-31MAR2017); the first diagnosis date was the index date. Non-RA patients were 1:1 propensity score matched to RA patients by age, sex, race, and index year. The index date for non-RA patients was randomly selected to reduce bias. Health care costs and hospitalizations during the 1-year post-index period were compared between RA and non-RA cohorts. Logistic regression was performed to identify predictors of hospitalization. This study included 100,847 matched pairs. The mean age was 66 years; most patients were Caucasian (73.28%) and male (89.79%). Compared with non-RA patients, RA patients had a significantly higher mean Charlson comorbidity index (CCI) score (1.7 vs 1.1) and a higher proportion of patients with ≥1 hospitalization (9.4% vs 3.3%; all p<0.0001). Mean inpatient ($3,430 vs $1,181), outpatient ($6,396 vs $2,719), pharmacy ($1,951 vs $679), and total health care costs ($11,776 vs $4,579; all p<0.0001) were nearly three times higher for patients with vs without RA. Logistic regression analysis results revealed the following independent hospitalization predictors: upper-middle age (55-64 years) (odds ratio [OR]: 1.22, 95% confidence interval [CI]: 1.16-1.28), male (OR: 1.13, 95% CI: 1.04-1.22), African American (OR: 1.23, 95% CI: 1.07-1.41), and higher CCI scores (OR: 1.24, 95% CI: 1.23-1.26). Over a 1-year period, RA patients in the US VHA population had more hospitalizations and higher economic burden than patients without RA. The risk of hospitalization was higher among older African American men with higher CCI scores.

Positive predictive value of first-time rheumatoid arthritis diagnoses and their serological subtypes in the Danish National Patient Registry.

PurposesTo assess whether the positive predictive value (PPV) of first-time rheumatoid arthritis (RA) diagnosis registration in the Danish National Patient Registry increases when data are linked to the RA treatment codes and to assess the PPV of first-time RA diagnoses according to RA serological subtypes.MethodsParticipants from the Danish Diet, Cancer, and Health cohort with at least one RA diagnosis, registered at one of the Central Denmark Region hospitals in the Danish National Patient Registry during the period 1977–2016, were identified. Register-based RA diagnoses were verified by scrutinizing medical records against RA classification criteria or clinical case RA. PPVs for overall RA, seropositive RA, and other RA were calculated for two models: first-time RA diagnosis registration ever in the Danish National Patient Registry and first-time RA diagnosis registration ever where subsequently a prescription had been redeemed for a synthetic disease-modifying antirheumatic drug.ResultsOverall, 205 of 311 first-time register-based RA diagnoses were verified (PPV: 61.9%; 95% CI: 56.9–67.0). Regarding RA serological subtypes, 93 of 150 register-based seropositive RA (PPV: 62.0; 95% CI: 53.9–69.5) and 36 of 144 other RA (PPV: 25.0; 95% CI: 18.5–32.8) were confirmed. When register-based RA diagnosis codes were linked to RA treatment codes, the PPVs increased substantially: the PPV for overall RA was 87.7% (95% CI: 82.5–91.5), the PPV for seropositive RA was 80.2% (95% CI: 71.6–86.7), and the PPV for other RA was 41.1% (95% CI: 30.2–52.9).ConclusionThe first-time RA diagnoses in the Danish National Patient Registry should be used with caution in epidemiology research. However, linking registry-based RA diagnoses to the subsequent RA treatment codes increases the probability of identifying true RA diagnoses, especially overall RA and seropositive RA.

Risk of malignancy in patients with rheumatoid arthritis after anti-tumor necrosis factor therapy: results from Korean National Health Insurance claims data.

Background/AimsInhibition of tumor necrosis factor (TNF) is an effective treatment for rheumatoid arthritis (RA), but safety concerns about malignancy remain. The aim of this study was to evaluate cancer risk in RA patients treated with TNF inhibitors (TNFi), based on Korean Nationwide Health Insurance claims data.MethodsPatients with seropositive RA were selected from the health insurance database containing all citizens’ medical information, based on both RA diagnosis codes and medications. Between 2010 and 2014, RA patients treated with conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs) and TNFi were enrolled and followed up. We compared the cancer incidence between patients treated with TNFi and csDMARDs using incidence rate ratios (IRRs) after adjustment for age, gender, and observational periods.ResultsOf 45,423 selected patients with seropositive RA, 2,337 were treated with TNFi and 43,086 were treated with csDMARDs. The TNFi group was younger and was followed-up for a longer duration. During the observational period, 1,732 and 49 cases of cancer were detected in patients treated with csDMARDs and TNFi, respectively. Old age and male sex were associated with cancer occurrence. Adjusted IRRs for all cancers and common cancers demonstrated that cancer incidence did not differ significantly between the TNFi group and csDMARDs group (IRR = 0.913 for all cancers, p = 0.546).ConclusionsThis study revealed that cancer incidence was similar in RA patients treated with TNFi and csDMARDs. Anti-TNF therapy may be a safe therapeutic option for RA treatment, in terms of malignancy.

Temporal trends in prevalence, incidence, and mortality for rheumatoid arthritis in Quebec, Canada: a population-based study.

Health administrative data are a potentially efficient resource to conduct population-based research and surveillance, including trends in incidence and mortality over time. Our objective was to explore time trends in incidence and mortality for rheumatoid arthritis (RA), as well as estimating period prevalence. Our RA case definition was based on one or more hospitalizations with a RA diagnosis code, or three or more RA physician-billing codes, over 2years, with at least one RA billing code by a rheumatologist, orthopedic surgeon, or internist. To identify incident cases, a "run-in" period of 5years (1996-2000) was used to exclude prevalent cases. Crude age and sex-specific incidence rates were calculated (using data from 2001 to 2015), and sex-specific incidence rates were also standardized to the 2001 age structure of the Quebec population. We linked the RA cohort (both prevalent and incident patients) to the vital statistics registry, and standardized mortality rate ratios were generated. Negative binomial regression was used to test for linear change in standardized incidence rates and mortality ratios. The linear trends in standardized incidence rates did not show significant change over the study period. Mortality in RA was significantly higher than the general population and this remained true throughout the study period. Our prevalence estimate suggested 0.8% of the Quebec population may be affected by RA. RA incidence appeared relatively stable, and mortality was substantially higher in RA versus the general population and remained so over the study period. This suggests the need to optimize long-term RA outcomes.

Temporal Trends in Use of Biologic DMARDs for Rheumatoid Arthritis in the United States: A Cohort Study of Publicly and Privately Insured Patients.

Ten biologic disease-modifying antirheumatic drugs (bDMARDs) are available as treatment for rheumatoid arthritis (RA), but relatively little is known about population-level time trends in the use of these agents. To describe time trends in the use of bDMARDs in RA patients with private or public insurance in the United States. Claims data from private (Optum Clinformatics, 2004-2015) and public (Medicaid Analytic eXtract [MAX], 2000-2010) insurance programs were used. Patients with RA diagnosis codes and continuous health plan enrollment for 1-year baseline and 1-year follow-up periods were identified into 2 separate cohorts: (1) patients not using any bDMARD or (2) patients using a single bDMARD during the baseline period. Initiation of the first bDMARD from group 1 and switch to a second bDMARD from group 2 was identified as the outcome of interest during the 1-year follow-up period. Using mixed-effects regression models, we calculated yearly rates of initiation and switch for bDMARDs, adjusted for case-mix. We also described the proportion of all initiations and switches accounted for by each agent. There were 113,031 RA patients with public insurance and 97,751 RA patients with private insurance who were included in the study. The rates of initiation of bDMARDs (per 100 patients) increased significantly over time in Medicaid data for incident RA patients (from 1.1 to 3.1, P = 0.0006) and prevalent RA patients (from 4.6 to 10.9, P = 0.008). In Optum Clinformatics data, the rates were stable, with 7.7 to 8.3 per 100 incident RA patients (P = 0.10) and 11.0 to 11.5 per 100 prevalent RA patients (P = 0.12). The rates of switching (per 100 patients) increased over time from 6.4 to 16.0 (P = 0.04) in Medicaid data and 9.1 to 17.0 (P = 0.00003) in Optum Clinformatics data. Use of etanercept as the most common first-line agent was stable at approximately 50% of all biologic initiations, but use of infliximab decreased and the use of newer agents increased. More RA patients used bDMARDs in recent years, and use of newer agents, including certolizumab, golumumab, and tocilizuamab, is rising, which highlights a need for further comparative safety and effectiveness research of these agents to better guide evidence-based decision making. This study was supported by an investigator-initiated research grant from Pfizer. The study was conducted by the authors independent of the sponsor. The sponsor was given the opportunity to make nonbinding comments on a draft of the manuscript, but the authors retained the right of publication and determined the final wording. Solomon receives salary support through research support to his hospital from Amgen, Pfizer, AstraZeneca, Genentech, Lilly, Bristol-Myers Squibb, and CORRONA. Kim receives research grants from AstraZeneca, Lilly, Pfizer, Bristol-Myers Squibb, and Genentech. Desai receives research grants from Merck. Study concept and design were contributed by Desai and Kim. Liu took the lead in data collection, along with Jin, Desai, and Kim. All authors contributed equally in the interpretation of the results. The manuscript was written and revised primarily by Desai, along with Kim and the other authors.

The Economic Burden of ACPA-Positive Status Among Patients with Rheumatoid Arthritis.

Anticitrullinated protein antibodies (ACPAs) are serological biomarkers associated with early, rapidly progressing rheumatoid arthritis (RA), including more severe disease and joint damage. ACPA testing has become a routine tool for RA diagnosis and prognosis. Furthermore, treatment efficacy has been shown to vary by ACPA-positive status. However, it is not clear if the economic burden of patients with RA varies by ACPA status. To determine if the economic burden of RA varies by patient ACPA status. IMS PharMetrics Plus health insurance claims and electronic medical record (EMR) data from 2010-2015 were used to identify patients with incident RA. Patients were aged ≥ 18 years, had ≥ 1 inpatient or ≥ 2 outpatient claims reporting an RA diagnosis code (ICD-9-CM code 714.0), and had an anticyclic citrullinated peptide (anti-CCP; a surrogate of ACPA) antibody test within 6 months of diagnosis. Incident patients were defined as those who had no claims with an RA diagnosis code in the 6 months before the first observed RA diagnosis. The primary outcome of interest was RA-related medical expenditures, defined as the sum of payer- and patient-paid amounts for all claims with an RA diagnosis code. Secondary outcomes included health care utilization metrics such as treatment with a disease-modifying antirheumatic drug (DMARD) and physician visits. Generalized linear regression models were used for each outcome, controlling for ACPA-positive status (defined as anti-CCP ≥ 20 AU/mL), age, sex, and Charlson Comorbidity Index score as explanatory variables. Of 647,171 patients diagnosed with RA, 89,296 were incident cases, and 47% (n = 42,285) had an anti-CCP test. After restricting this sample to patients with a linked EMR and reported anti-CCP test result, 859 remained, with 24.7% (n = 212) being ACPA-positive. Compared with ACPA-negative patients, adjusted results showed that ACPA-positive patients were more likely to use either conventional (71.2% vs. 49.6%; P < 0.001) or biologic (20.3% vs. 11.8%; P < 0.001) DMARDs during the first year after diagnosis and had more physician visits (5.58 vs. 3.91 times per year; P < 0.001). Annual RA-associated total expenditures were $7,941 for ACPA-positive and $5,243 for ACPA-negative patients (Δ = $2,698; P = 0.002). RA-associated medical expenditures were $4,380 for ACPA-positive and $3,427 for ACPA-negative patients (Δ = $954; P = 0.168), whereas DMARD expenditures were $3,560 and $1,817, respectively (Δ = $1,743; P = 0.001). RA-related economic burden is higher for patients who are ACPA-positive compared with those who are ACPA-negative. Providers may wish to inform patients diagnosed with ACPA-positive RA about the likely future disease and economic burden in hopes that both stakeholders can be more proactive in addressing them. Funding for this research was contributed by Bristol-Myers Squibb. Patel and Price are employees and stockholders of Bristol-Myers Squibb. Shafrin and Tebeka are employees of Precision Health Economics, a health care consulting firm that received funding from Bristol-Myers Squibb to conduct this study. Michaud has received a grant from Pfizer and is employed by the National Data Bank for Rheumatic Diseases, which has received funds from Amgen, Bristol-Myers Squibb, Eli Lilly, Janssen, Pfizer, and Regeneron. Study concept and design were contributed by Shafrin, Price, Patel, and Michaud. Shafrin, Price, and Patel collected the data, and all authors contributed equally to data analysis. The manuscript was written by Shafrin and Tebeka and revised by Shafrin, Price, Patel, and Michaud.

An administrative data validation study of the accuracy of algorithms for identifying rheumatoid arthritis: the influence of the reference standard on algorithm performance.

BackgroundWe have previously validated administrative data algorithms to identify patients with rheumatoid arthritis (RA) using rheumatology clinic records as the reference standard. Here we reassessed the accuracy of the algorithms using primary care records as the reference standard.MethodsWe performed a retrospective chart abstraction study using a random sample of 7500 adult patients under the care of 83 family physicians contributing to the Electronic Medical Record Administrative data Linked Database (EMRALD) in Ontario, Canada. Using physician-reported diagnoses as the reference standard, we computed and compared the sensitivity, specificity, and predictive values for over 100 administrative data algorithms for RA case ascertainment.ResultsWe identified 69 patients with RA for a lifetime RA prevalence of 0.9%. All algorithms had excellent specificity (>97%). However, sensitivity varied (75-90%) among physician billing algorithms. Despite the low prevalence of RA, most algorithms had adequate positive predictive value (PPV; 51-83%). The algorithm of “[1 hospitalization RA diagnosis code] or [3 physician RA diagnosis codes with ≥1 by a specialist over 2 years]” had a sensitivity of 78% (95% CI 69–88), specificity of 100% (95% CI 100–100), PPV of 78% (95% CI 69–88) and NPV of 100% (95% CI 100–100).ConclusionsAdministrative data algorithms for detecting RA patients achieved a high degree of accuracy amongst the general population. However, results varied slightly from our previous report, which can be attributed to differences in the reference standards with respect to disease prevalence, spectrum of disease, and type of comparator group.

Utilization and Adherence Patterns of Subcutaneously Administered Anti–Tumor Necrosis Factor Treatment Among Rheumatoid Arthritis Patients

BackgroundAdherence to therapy is a key requirement underlying achievement of clinical outcomes in randomized controlled drug registration trials. In postmarketing studies, comparison of adherence among therapies can become more complicated when drug dosing and administration schedules differ or when methods used to measure adherence are not consistently applied. ObjectiveThe objective of this exploratory study was to investigate a broad range of utilization and adherence outcomes associated with subcutaneous biologic treatments for rheumatoid arthritis (RA). MethodsAdult patients (aged ≥18 years) exhibiting ≥2 claims with an RA diagnosis (code 714.x), at least 24 months of continuous medical and pharmacy eligibility, and 30-day supplies of adalimumab, etanercept, or golimumab were selected from the Optum Insight Clinformatics database. Adherence and utilization measures were calculated and compared across treatment groups. ResultsA total of 1532 adalimumab, 2099 etanercept, and 261 golimumab patients met inclusion criteria. Compared with both adalimumab and etanercept patients, golimumab patients were significantly more likely to have a medication possession ratio of ≥0.80 (82% vs 71% vs 62%; P < 0.001) and significantly less likely to have ≥4 late medication refills (6.9% vs 17.7% vs 26.1%; P < 0.001 for all). Etanercept patients had significantly greater refill intervals (37.7 vs 34.9 and 35.1 days) and had the lowest proportion of adherent fills (70% vs 77% and 75%) compared with both golimumab and adalimumab patients (P < 0.001 for all). Bivariate effects were reproduced in multivariate models that controlled for treatment duration. ConclusionsA number of statistically significant medication adherence differences were observed among golimumab, adalimumab, and etanercept patients in treatment for RA. Overall, golimumab patients appeared to be the most adherent group. Findings may be partially attributable to golimumab patients’ likely increased disease severity, their prior experience with biologic medication, or golimumab’s once-monthly dosing schedule, which requires fewer administrations than both adalimumab and etanercept.

Increased Risk of Complications Following Total Joint Arthroplasty in Patients With Rheumatoid Arthritis

Most of the evidence regarding complications following total hip arthroplasty (THA) and total knee arthroplasty (TKA) are based on patients with osteoarthritis (OA); less is known about outcomes in rheumatoid arthritis (RA). Using a validated algorithm for identifying patients with RA, we undertook this study to compare the rates of complications among THA and TKA recipients between those with RA and those without RA. In patients who underwent a first primary elective THA or TKA between 2002 and 2009, those with RA were identified using a validated algorithm: a hospitalization with a diagnosis code for RA or 3 physician billing claims with a diagnosis code for RA, with at least 1 claim by a specialist (rheumatologist, orthopedic surgeon, or internist) in a 2-year period. Recipients with diagnostic codes suggesting an inflammatory arthritis, but not meeting RA criteria, were classified as having inflammatory arthritis. All remaining patients were deemed to have OA. Cox proportional hazards models, censored on death, were used to determine the relationship between the type of arthritis and the occurrence of specific complications, adjusting for potential confounders (age, sex, comorbidity, and provider volume). We identified 43,997 eligible THA recipients (3% with RA) and 71,793 eligible TKA recipients (4% with RA). Total joint arthroplasty recipients with RA had higher age and sex-standardized rates of dislocation following THA (2.45%, compared with 1.21% for recipients with OA) and higher age and sex-standardized rates of infection following TKA (1.26%, compared with 0.84% for recipients with OA). Controlling for potential confounders, recipients with RA remained at increased risk of dislocation within 2 years of THA (adjusted hazard ratio [HR] 1.91, P = 0.001) and remained at increased risk of infection within 2 years of TKA (adjusted HR 1.47, P = 0.03) relative to recipients with OA. Patients with RA are at higher risk of dislocation following THA and are at higher risk of infection following TKA relative to those with OA. Further research is warranted to elucidate explanations for these findings, including the roles of medication profile, implant choice, postoperative antibiotic protocol, and method of rehabilitation following joint replacement.

Accuracy of Canadian Health Administrative Databases in Identifying Patients With Rheumatoid Arthritis: A Validation Study Using the Medical Records of Rheumatologists

Health administrative data can be a valuable tool for disease surveillance and research. Few studies have rigorously evaluated the accuracy of administrative databases for identifying rheumatoid arthritis (RA) patients. Our aim was to validate administrative data algorithms to identify RA patients in Ontario, Canada. We performed a retrospective review of a random sample of 450 patients from 18 rheumatology clinics. Using rheumatologist-reported diagnosis as the reference standard, we tested and validated different combinations of physician billing, hospitalization, and pharmacy data. One hundred forty-nine rheumatology patients were classified as having RA and 301 were classified as not having RA based on our reference standard definition (study RA prevalence 33%). Overall, algorithms that included physician billings had excellent sensitivity (range 94-100%). Specificity and positive predictive value (PPV) were modest to excellent and increased when algorithms included multiple physician claims or specialist claims. The addition of RA medications did not significantly improve algorithm performance. The algorithm of "(1 hospitalization RA code ever) OR (3 physician RA diagnosis codes [claims] with ≥1 by a specialist in a 2-year period)" had a sensitivity of 97%, specificity of 85%, PPV of 76%, and negative predictive value of 98%. Most RA patients (84%) had an RA diagnosis code present in the administrative data within ±1 year of a rheumatologist's documented diagnosis date. We demonstrated that administrative data can be used to identify RA patients with a high degree of accuracy. RA diagnosis date and disease duration are fairly well estimated from administrative data in jurisdictions of universal health care insurance.

Treatment of rheumatoid arthritis in the Medicare Current Beneficiary Survey

IntroductionNumerous studies across different health systems have documented that many patients with rheumatoid arthritis (RA) do not receive disease-modifying anti-rheumatic drugs (DMARDs). Relatively little is known about correlates of DMARD use and whether there are socioeconomic and demographic disparities. We examined DMARD use during 2001 to 2006 in the Medicare Current Beneficiary Survey (MCBS), a longitudinal US survey of randomly selected Medicare beneficiaries.MethodsParticipants in MCBS with RA were included in the analyses, and DMARD use was based on an in-home assessment of all medications. Variables included as potential correlates of DMARD use in weighted regression models included race/ethnicity, insurance, income, education, rheumatology visit, region, age, gender, comorbidity index, and calendar year.ResultsThe cohort consisted of 509 MCBS participants with a diagnosis code for RA. Their median age was 70 years, 72% were female, and 24% saw a rheumatologist. Rates of DMARD use ranged from 37% among those <75 years of age to 25% of those age 75 to 84 and 4% of those age 85 and older. The multivariable adjusted predictors of DMARD use include: visit with a rheumatologist in the prior year (odds ratio, OR, 7.74, 95% CI, 5.37, 11.1) and older patient age (compared with <75 years, ages 75 to 84, OR 0.58, 95% CI 0.37, 0.92, and 85 and over, OR 0.09, 95% CI 0.02, 0.31). In those without a rheumatology visit, lower income and older age were associated with a significantly reduced probability of DMARD use; no association of DMARD use with income or age was observed for subjects seen by rheumatologists. Race and ethnicity were not significantly associated with receipt of DMARDs.ConclusionsAmong individuals not seeing rheumatologists, lower income and older age were associated with a reduced probability of DMARD use.

Adalimumab, etanercept, and infliximab utilization patterns and drug costs among rheumatoid arthritis patients

Objectives:To evaluate the utilization patterns of the anti-tumor necrosis factor (anti-TNF) agents Humira (adalimumab), Enbrel (etanercept), and Remicade (infliximab) in patients with rheumatoid arthritis (RA) and compare medication costs during the first year of treatment. (Humira is a registered trademark of Abbott Laboratories, IL; Enbrel is a registered trademark of Immunex Corporation, CA; and Remicade is a registered trademark of Janssen Biotech, Inc., PA).Methods:This retrospective analysis of medical and pharmacy claims included patients who were aged ≥18 years, had ≥2 RA diagnosis codes, and had ≥365 days of persistence with the index anti-TNF. Patients excluded had claims for anti-TNF agents within 6 months before the index date. Refill patterns for adalimumab and etanercept, number of infliximab infusions, time between infusions, and dose per infusion were analyzed for 12 months. Direct anti-TNF medication costs were compared among anti-TNFs for the initial treatment year.Results:Infliximab-treated patients (n = 457) were significantly older than adalimumab- (n = 337) or etanercept-treated patients (n = 902). Time between refills was longer than recommended for 28% and 30% of adalimumab and etanercept refill periods, respectively. Potential cumulative time without therapy was 33 days for adalimumab and 43 days for etanercept. Statistically significant differences in mean per-patient anti-TNF medication costs for the first year were reported for adalimumab, etanercept, and infliximab ($14,991, $13,361, and $18,139, respectively; p < 0.0001); however, a cost assessment using labeled dosing of the anti-TNF agents with optimal treatment compliance yielded comparable annual medication costs.Limitations:This analysis only evaluated utilization patterns for selected anti-TNF agents and was not inclusive of other medications that patients may have been using for RA. Absolute patient adherence could not be assessed due to lack of information on how patients were self-administering adalimumab and etanercept or if samples of the agents were made available.Conclusions:This study identified gaps in patients’ refills compared with prescriber recommendations. The infliximab-treated group had infusion patterns consistent with prescribing information. Potential clinical and economic implications of dose attenuation with adalimumab and etanercept should be explored further.

Analysis of drug and administrative costs allowed by U.S. Private and public third-party payers for 3 intravenous biologic agents for rheumatoid arthritis.

Rheumatoid arthritis (RA) is a common chronic condition with substantial morbidity that can now be treated with disease-modifying biologic agents that target tumor necrosis factor (TNF) or related mechanisms. The anti-TNF biologic agents are available in either intravenous (IV) or subcutaneous dose forms. The biologic agents with an indication for rheumatoid arthritis and administered only by IV infusion in medical offices include abatacept, infliximab, and rituximab. Although the literature on RA treatments, their outcomes, and aspects of their costs is substantial, the costs of administration by the IV route have not been directly studied. To assess the detailed costs of administering IV biologic agents for the treatment of RA in relation to the total cost of the medication itself in the United States. The sample included all patients with at least 1 medical claim with an ICD-9-CM diagnosis code for RA (codes 714.XX) in any claim field and at least 1 claim for infliximab, abatacept, or rituximab (HCPCS codes J1745, J0129, and J9310, respectively) at any time from January 1, 2006, through December 31, 2008, in a database associated with billing and claims administration for 72 U.S. medical clinics. Costs were determined using the payer allowed payment, which is the total contractual amount that the provider should receive, including the patient cost share. Costs were measured as the average cost per IV administration visit and in relation to the dose of medication billed. The authors verified that an RA diagnosis was present on 100% of infusion claims for the study drugs. Over the study period for claims with dates of service from January 1, 2006, through December 31, 2008, 72 medical clinics had claims for a total of 4,248 unique patients with RA and a total of 33,354 clinic visits in which these patients received at least 1 infusion of 1 of 3 biologic agents (26,586 for infliximab, 4,807 for abatacept, and 1,961 for rituximab). Mean (SD) total payment for all drugs and other cost components was $2,874 ($1,515) per visit, of which IV administration costs were $226 (7.9%); the mean cost of the biologic agent itself was $2,616 (91.0%), and other visit-related services were $33 (1.1%). For individual agents, the total costs of visits were $2,828, $1,827, and $6,076; and the costs of IV administration were $224, $171, and $390, respectively, for infliximab, abatacept, and rituximab. For patients who received an IV biologic agent to treat RA, IV administration costs accounted for 7.9% of the total cost of the visit.