Computerized definitions showed high positive predictive values for identifying hospitalizations for congestive heart failure and selected infections in Medicaid enrollees with rheumatoid arthritis

Prevalence and Factors Associated with De-escalation of Anti-TNFs in Older Adults with Rheumatoid Arthritis: A Medicare Claims-Based Observational Study

OBJECTIVE

The aim was to evaluate prevalence and factors associated with anti-tumor necrosis factor (anti-TNF) de-escalation in older adults with rheumatoid arthritis (RA).

METHODS

We identified adults ≥ 66 years of age with RA on anti-TNF therapy within 6 months after RA diagnosis with at least 6-7 months duration of use (proxy for stable use), using 20% Medicare data from 2008-2017. Patient demographic and clinical characteristics, including concomitant use of glucocorticoid (GC), were collected. Anti-TNF use was categorized as either de-escalation (identified by dosing interval increase, dose reduction, or cessation of use) or continuation. We used (1) an observational cohort design with Cox regression to assess patient characteristics associated with de-escalation and (2) a case-control design with propensity score-adjusted logistic regression to assess the association of de-escalation with different clinical conditions and concomitant medication use.

RESULTS

We identified 5106 Medicare beneficiaries with RA on anti-TNF, 65.5% of whom had de-escalation. De-escalation was more likely with older age (hazard ratio [HR] 1.01, 95% confidence interval [CI] 1.01-1.02) or greater comorbidity (HR 1.07, 95% CI 1.05-1.09), but was less likely with low-income subsidy status (HR 0.85, 95% CI 0.78-0.92), adjusting for patient sex and race/ethnicity. Lower odds of de-escalation were associated with serious infection (odds ratio [OR] 0.79, 95% CI 0.66-0.94), new heart failure diagnosis (OR 0.70, 95% CI 0.52-0.95), and long-term GC use (OR 0.84, 95% CI 0.74-0.95), whereas higher odds were associated with concomitant methotrexate use (OR 1.16, 95% CI 1.03-1.31).

CONCLUSIONS

Anti-TNFs are de-escalated in two-thirds of older adults with RA in usual care. Further study is needed on RA outcomes after anti-TNF de-escalation.

Frailty and Risk of Serious Infections in Patients With Rheumatoid Arthritis Treated With Biologic or Targeted-Synthetic Disease-Modifying Antirheumatic Drugs

OBJECTIVE

It remains unknown whether frailty status portends an increased risk of adverse outcomes in patients with rheumatoid arthritis (RA) initiating biologic or targeted-synthetic (b/ts) disease-modifying antirheumatic drugs (DMARDs). The objective of our study was to evaluate the association between frailty and serious infections in a younger population of patients (<65 years old) with RA who initiated b/tsDMARDs.

METHODS

Using MarketScan data, we identified new users of tumor necrosis factor inhibitors (TNFi), non-TNFi biologic DMARDs, or Janus kinase inhibitors (JAKi) between 2008 and 2019 among those with RA. Patients' baseline frailty risk score was calculated using a Claims-Based Frailty Index (≥0.2 defined as frail) 12 months prior to drug initiation. The primary outcome was time to serious infection; secondarily, we examined time-to-any infection and all-cause hospitalizations. We used Cox proportional hazards to estimate adjusted hazard ratios and 95% confidence intervals (95% CIs) and assessed the significance of interaction terms between frailty status and drug class.

RESULTS

A total of 57,980 patients, mean (±SD) age 48.1 ± 10.1 were included; 48,139 (83%) started TNFi, 8,111 (14%) non-TNFi biologics, and 1,730 (3%) JAKi. Among these, 3,560 (6%) were categorized as frail. Frailty was associated with a 50% increased risk of serious infections (adjusted hazard ratio [95% CI] 1.5, 1.2-1.9) and 40% higher risk of inpatient admissions (1.4 [1.3-1.6]) compared with nonfrail patients among those who initiated TNFi. Frailty was also associated with a higher risk of any infection relative to nonfrail patients among those on TNFi (1.2 [1.1-1.3]) or non-TNFi (1.2 [1.0-1.4]) or JAKi (1.4 [1.0-2.0]).

CONCLUSION

Frailty is an important predictor for the risk of adverse outcomes among patients with RA treated with biologic or targeted-synthetic DMARDs.

Best Practices for Identifying Hospitalized Lower Respiratory Tract Infections Using Administrative Data: A Systematic Literature Review of Validation Studies

INTRODUCTION

Estimating the burden of lower respiratory tract infections (LRTIs) increasingly relies on administrative databases using International Classification of Diseases (ICD) codes, but no standard methodology exists. We defined best practices for ICD-based algorithms that estimate LRTI incidence in adults.

METHODS

We conducted a systematic review of validation studies assessing the use of ICD code-based algorithms to identify hospitalized LRTIs in adults, published in Medline, EMBASE, and LILACS between January 1996 and January 2022, according to PRISMA guidelines. We assessed sensitivity, specificity, and other accuracy measures of different algorithms.

RESULTS

We included 26 publications that used a variety of ICD code-based algorithms and gold standard criteria, and 18 reported sensitivity and/or specificity. Sensitivity was below 80% in 72% (38/53) of algorithms and specificity exceeded 90% in 77% (37/48). Algorithms for all-cause LRTI (n = 18) that included only pneumonia codes in primary position (n = 3) had specificity greater than 90% but low sensitivity (55-72%). Sensitivity increased by 5-15%, with minimal loss in specificity, with the addition of primary codes for severe pneumonia (e.g. sepsis) while pneumonia codes were in secondary position, and by 13% with codes from LRTI-related infections (e.g. viral) or other respiratory diseases (e.g. empyema). Sensitivity increased by 8% when pneumonia codes were in any position, but specificity was not reported. In hospital-acquired pneumonia and pneumococcal-specific pneumonia, algorithms containing only nosocomial- or pathogen-specific ICD codes had poor sensitivity, which improved when broader pneumonia codes were added, in particular codes for unspecified organisms.

CONCLUSION

Our systematic review highlights that most ICD code-based algorithms are relatively specific, but miss a substantial number of hospitalized LRTI adult cases. Best practices to estimate LRTI incidence in this population include the use of all pneumonia ICD codes for any LRTI outcome and, to a lesser extent, those for other LRTI-related infections or respiratory diseases.

Initiation of Disease-Modifying Antirheumatic Drugs in Older Medicare Beneficiaries With New Diagnosis of Late-Onset Rheumatoid Arthritis

OBJECTIVE

Older adults with rheumatoid arthritis (RA) account for up to one-third of the RA population and are less likely to receive optimal treatment. For the subgroup of older adults with late-onset RA (LORA), who experience more symptomatic and progressive disease, suboptimal treatment could be more consequential than the general population who age with RA. We evaluated use of disease-modifying antirheumatic drugs (DMARDs) in older adults with a new diagnosis of LORA.

METHODS

In this retrospective observational study, we identified adults 66 years of age or older with a new diagnosis of LORA using Medicare data from 2008 to 2017. Information on baseline patient characteristics and DMARD initiation during the first 12 months after LORA diagnosis were collected. We also assessed concomitant use of glucocorticoids (GCs).

RESULTS

We identified 33,373 older adults with new diagnosis of LORA. Average age at LORA diagnosis was 76.7 (SD 7.6); 75.4% were female, 76.9% were White, and 35.6% had low-income subsidy (LIS). Less than one-third were initiated on a DMARD (28.9%). In multivariable analyses, DMARD initiation was associated with younger age, fewer comorbidities, and absence of LIS status. Concomitant long-term (>3 months) GC use was higher among those on any DMARD (44.3%) compared with those without (15.2%).

CONCLUSIONS

DMARD initiation after new diagnosis of LORA is low despite current clinical practice guidelines recommending early aggressive initiation of treatment. Long-term GC use is common among those on any DMARDs, raising concern for suboptimal DMARD use. Further studies are needed to understand drivers of DMARD use in older adults.

Risk of infection from glucocorticoid and methotrexate interaction in patients with rheumatoid arthritis using biologics: A retrospective cohort study

AIMS

This retrospective cohort study aimed to evaluate the effect of the interaction between methotrexate and glucocorticoids on the risk of developing bacterial infections in patients with rheumatoid arthritis (RA) using biological disease-modifying antirheumatic drugs (bDMARDs).

METHODS

We used the 2005-2018 JMDC claims database, a nationwide claims database in Japan. From the database of 7 175 048 patients, study patients were obtained by applying the following exclusion criteria: no use of bDMARDs; without information on the date of prescription; without RA as a disease; other than the new users of bDMARDs; and age <18 years. The exposures were glucocorticoids and methotrexate, and the outcome was bacterial infection. The interaction effects were examined using multivariate Cox regression analysis. Bacterial infections were identified according to antibiotic prescription and International Statistical Classification of Diseases and Related Health Problems, 10th revision codes.

RESULTS

A total of 2837 RA patients were identified, with a median age of 50 years. The incidence of infection was 16.8% (95% confidence interval: 15.5-18.3). The interaction term for the doses of glucocorticoids and methotrexate was significant. Additionally, a higher dose of glucocorticoid was a significant risk factor for developing bacterial infections on the side of high doses of methotrexate. The incidence of bacterial infections tended to increase significantly with increasing methotrexate doses coprescribed with glucocorticoids ≥5 mg or glucocorticoid doses coprescribed with methotrexate ≥8 mg.

CONCLUSION

Our results indicate a potential association between methotrexate dose and bacterial infections during bDMARDs administration with glucocorticoids in patients with RA.

Effectiveness and Safety of Biologic Therapy in Hispanic Vs Non-Hispanic Patients With Inflammatory Bowel Diseases: A CA-IBD Cohort Study

BACKGROUND & AIMS

There are limited data on outcomes of biologic therapy in Hispanic patients with inflammatory bowel diseases (IBDs). We compared risk of hospitalization, surgery, and serious infections in Hispanic vs non-Hispanic patients with IBD in a multicenter, electronic health record-based cohort of biologic-treated patients.

METHODS

We identified adult patients with IBD who were new users of biologic agents (tumor necrosis factor α [TNF-α] antagonists, ustekinumab, vedolizumab) from 5 academic institutions in California between 2010 and 2017. We compared the risk of all-cause hospitalization, IBD-related surgery, and serious infections in Hispanic vs non-Hispanic patients using 1:4 propensity score matching and survival analysis.

RESULTS

We compared 240 Hispanic patients (53% male; 45% with ulcerative colitis; 73% TNF-α antagonist-treated; 20% with prior biologic exposure) with 960 non-Hispanic patients (51% male; 44% with ulcerative colitis; 67% TNF-α antagonist-treated; 27% with prior biologic exposure). After propensity score matching, Hispanic patients were younger (37 ± 15 vs 40 ± 16 y; P = .02) and had a higher burden of comorbidities (Elixhauser index, >0; 37% vs 26%; P < .01), without any differences in patterns of medication use, burden of inflammation, and hospitalizations. Within 1 year of biologic initiation, Hispanic patients had higher rates of hospitalizations (31% vs 23%; adjusted hazard ratio [aHR], 1.32; 95% CI, 1.01-1.74) and IBD-related surgery (7.1% vs 4.6%; aHR, 2.00; 95% CI, 1.07-3.72), with a trend toward higher risk of serious infections (8.8% vs 4.9%; aHR, 1.74; 95% CI, 0.99-3.05).

CONCLUSIONS

In a multicenter, propensity score-matched cohort of biologic-treated patients with IBD, Hispanic patients experienced higher rates of hospitalization, surgery, and serious infections. Future studies are needed to investigate the biological, social, and environmental drivers of these differences.

Effect of Obesity on Risk of Hospitalization, Surgery, and Serious Infection in Biologic-Treated Patients With Inflammatory Bowel Diseases: A CA-IBD Cohort Study

INTRODUCTION

Obesity is variably associated with treatment response in biologic-treated patients with inflammatory bowel diseases (IBD). We evaluated the association between obesity and risk of hospitalization, surgery, or serious infections in patients with IBD in new users of biologic agents in a large, multicenter, electronic health record (EHR)-based cohort (CA-IBD).

METHODS

We created an EHR-based cohort of adult patients with IBD who were new users of biologic agents (tumor necrosis factor [TNF-α] antagonists, ustekinumab, and vedolizumab) between January 1, 2010, and June 30, 2017, from 5 health systems in California. Patients were classified as those with normal body mass index (BMI), overweight, or obese based on the World Health Organization classification. We compared the risk of all-cause hospitalization, IBD-related surgery, or serious infections among patients with obesity vs those overweight vs those with normal BMI, using Cox proportional hazard analyses, adjusting for baseline demographic, disease, and treatment characteristics.

RESULTS

Of 3,038 biologic-treated patients with IBD (69% with Crohn's disease and 76% on TNF-α antagonists), 28.2% (n = 858) were overweight, and 13.7% (n = 416) were obese. On a follow-up after biologic initiation, obesity was not associated with an increased risk of hospitalization (adjusted hazard ratio [aHR] vs normal BMI, 0.90; [95% confidence interval, 0.72-1.13]); IBD-related surgery (aHR, 0.62 [0.31-1.22]); or serious infection (aHR, 1.11 [0.73-1.71]). Similar results were observed on stratified analysis by disease phenotype (Crohn's disease vs ulcerative colitis) and index biologic therapy (TNF-α antagonists vs non-TNF-α antagonists).

DISCUSSION

In a multicenter, EHR-based cohort of biologic-treated patients with IBD, obesity was not associated with hospitalization, surgery, or serious infections. Further studies examining the effect of visceral obesity on patient-reported and endoscopic outcomes are needed.

Comparative Risk of Serious Infections With Tumor Necrosis Factor α Antagonists vs Vedolizumab in Patients With Inflammatory Bowel Diseases

BACKGROUND AND AIMS

We conducted a retrospective cohort study comparing the risk of serious infections between patients treated with tumor necrosis factor-a (TNFa) antagonists vs. vedolizumab in patients with inflammatory bowel diseases (IBD).

METHODS

Using an administrative claims database, we identified patients with IBD who were new-users of either TNFa antagonists or vedolizumab between 2014-2018 and had insurance coverage for at least 1y before and after treatment initiation. We compared the risk of serious infections (infections requiring hospitalization) between patients treated with vedolizumab or TNFa antagonists using marginal structural Cox proportional hazard models adjusted for baseline disease characteristics, healthcare utilization, comorbidities, and time-varying use of corticosteroids, immunomodulators and opiates.

RESULTS

We included 4881 patients treated with TNFa antagonists (age, 41 ± 15y, 60% with Crohn's disease [CD]) of whom 434 developed serious infections over 5786 person-year [PY] follow-up, and 1106 patients treated with vedolizumab (age, 44 ± 16y, 39% with CD) of whom 86 developed serious infections over 1040-PY follow-up. Vedolizumab was associated with 46% lower risk of serious infections as compared with TNFa antagonists in patients with ulcerative colitis (HR,0.54 [95% CI,0.35-0.83), but no significant differences were observed in patients with CD (HR,1.30 [0.80-2.11]). Vedolizumab was associated with lower risk of extra-intestinal serious infections in patients with UC, but higher risk of gastrointestinal serious infections in patients with CD.

CONCLUSIONS

In an observational study of patients with IBD, vedolizumab was associated with lower risk of serious infections as compared with TNFa antagonists, in patients with UC, but not in patients with CD.

Risk of Serious Infection With Low-dose Glucocorticoids in Patients With Rheumatoid Arthritis: An Instrumental Variable Analysis

BACKGROUND

Low-dose glucocorticoids are commonly used in the treatment of rheumatoid arthritis (RA). Observational studies have found an increased risk of serious infection associated with low-dose glucocorticoids, but concerns about residual confounding remain.

METHODS

We identified adults with RA on stable immunomodulatory therapy for >6 months receiving no glucocorticoids or ≤5 mg/day using Medicare data from 2006 to 2015. We used provider preference for glucocorticoids as an instrumental variable (IV) to assess associations between low-dose glucocorticoid use and the risk of infection requiring hospitalization using a cause-specific proportional hazards model.

RESULTS

We identified 163,603 qualifying treatment episodes among 120,656 patients. Glucocorticoids ≤5 mg/day were used by 25,373/81,802 (31.0%) of patients seen by a rheumatologist with low provider preference for glucocorticoids and by 36,087/81,801 (44.1%) of patients seen by a rheumatologist with high provider preference for glucocorticoids (adjusted odds ratio 1.81, 95% confidence interval 1.77, 1.84 for association between provider preference and glucocorticoids). Chronic obstructive pulmonary disease, opioids, antibiotics, previous emergency department visits, hospitalizations, and infections requiring hospitalization infections were unbalanced with regard to exposure but not to the IV. The incidence of infection requiring hospitalization was 8.0/100 person-years among patients unexposed to glucocorticoids versus 11.7/100 person-years among those exposed. The association between glucocorticoids and infection requiring hospitalization from IV analysis (hazard ratio 1.26 [1.02-1.56]) was similar to results from a standard multivariable model (hazard ratio 1.24 [1.21-1.28]).

CONCLUSIONS

Among patients with RA on stable immunomodulatory therapy, IV analysis based on provider preference demonstrated an increased risk of infection requiring hospitalization associated with low-dose glucocorticoids, similar to a traditional analysis.

Serious Infections in Patients With Gout in the US: A National Study of Incidence, Time Trends, and Outcomes

OBJECTIVE

To study the epidemiology of serious infections in patients hospitalized with gout.

METHODS

We identified patients with gout hospitalized with a primary diagnosis of pneumonia, sepsis/bacteremia, urinary tract infection (UTI), skin and soft tissue infections (SSTIs), or opportunistic infections (OIs) in a US National Inpatient Sample from 1998 to 2016 and examined factors associated with utilization and mortality.

RESULTS

We noted 1,140,085 hospitalizations of patients with serious infections and gout (11% of all hospitalizations of patients with gout; 1998-2000 [8.9%], 2015-2016 [14.5%]). Compared to patients without gout, patients with gout hospitalized with serious infections were older (median age 65 versus 74 years), more of them had a Charlson-Deyo comorbidity index score ≥2 (42% versus 65%), and fewer were female (53% versus 35%) or non-White (40% versus 35%), respectively. The most common infection was pneumonia (52%) in 1998-2000 and sepsis (52%) in 2015-2016. Median hospital charges and hospital stays were higher for patients with sepsis and OIs in 2015-2016 ($41,000-$42,000; 5.1-5.5 days) versus those with UTI, pneumonia, or SSTIs ($15,000-$17,000; 3.0-3.9 days). Compared to patients with sepsis, the multivariable-adjusted odds of health care utilization and in-hospital mortality were significantly lower for patients with UTI, SSTIs, and pneumonia, and non-home discharge or in-hospital mortality were lower in patients with OIs. Among patients hospitalized with infections, older age, Medicaid coverage, a higher Charlson-Deyo comorbidity index score, Black race, and Northeast and nonrural hospital location were associated with significantly higher health care utilization and mortality, while female sex, Medicare insurance, and lower income were associated with higher utilization.

CONCLUSION

Given an increasing rate of serious infections, especially sepsis and pneumonia, in individuals with gout, development of effective interventions targeting factors associated with health care utilization and mortality will improve outcomes and reduce burden.

Obesity Is Not Associated With an Increased Risk of Serious Infections in Biologic-Treated Patients With Inflammatory Bowel Diseases

INTRODUCTION

Obesity has been associated with adverse disease-related outcomes and inferior treatment response to biologic agents in patients with inflammatory bowel diseases (IBDs), but its impact on the risk of treatment-related complications is unknown. We performed a cohort study examining the association between obesity and risk of serious infections in biologic-treated patients with IBD.

METHODS

Using an administrative claims database, in a cohort of biologic-treated patients with IBD between 2014 and 2018 with follow-up 1 year before and after treatment initiation, we compared the risk of serious infections (infections requiring hospitalization) between obese vs nonobese patients (based on validated administrative claims) using Cox proportional hazard analysis.

RESULTS

We included 5,987 biologic-treated patients with IBD (4,881 on tumor necrosis factor-α antagonists and 1,106 on vedolizumab), of whom 524 (8.8%) were classified as obese. Of the 7,115 person-year follow-up, 520 patients developed serious infection. Risk of serious infection was comparable in obese vs nonobese patients (8.8% vs 8.5%; unadjusted hazard ratio, 1.15; 95% confidence interval, 0.86-1.54). After adjusting for age, comorbidities, disease characteristics, health care utilization, use of corticosteroids, immunomodulators, and opiates, obesity was not associated with an increased risk of serious infection (adjusted hazard ratio, 0.74 [95% confidence interval, 0.55-1.01]). Similar results were seen on stratified analysis by disease phenotype (Crohn's disease and ulcerative colitis) and index biologic therapy (tumor necrosis factor-α antagonists and vedolizumab).

DISCUSSION

After adjusting for comorbid conditions and disease characteristics, obesity is not independently associated with an increased risk of serious infections in biologic-treated patients with IBD.

Investigating changes in disease activity as a mediator of cardiovascular risk reduction with methotrexate use in rheumatoid arthritis

OBJECTIVE

Examine the association of methotrexate (MTX) use with cardiovascular disease (CVD) in rheumatoid arthritis (RA) using marginal structural models (MSM) and determine if CVD risk is mediated through modification of disease activity.

METHODS

We identified incident CVD events (coronary artery disease (CAD), stroke, heart failure (HF) hospitalisation, CVD death) within a multicentre, prospective cohort of US Veterans with RA. A 28-joint Disease Activity Score with C-reactive protein (DAS28-CRP) was collected at regular visits and medication exposures were determined by linking to pharmacy dispensing data. MSMs were used to estimate the treatment effect of MTX on risk of incident CVD, accounting for time-varying confounders between receiving MTX and CVD events. A mediation analysis was performed to estimate the indirect effects of methotrexate on CVD risk through modification of RA disease activity.

RESULTS

Among 2044 RA patients (90% male, mean age 63.9 years, baseline DAS28-CRP 3.6), there were 378 incident CVD events. Using MSM, MTX use was associated with a 24% reduced risk of composite CVD events (HR 0.76, 95% CI 0.58 to 0.99) including a 57% reduction in HF hospitalisations (HR 0.43, 95% CI 0.24 to 0.77). Individual associations with CAD, stroke and CVD death were not statistically significant. In mediation analyses, there was no evidence of indirect effects of MTX on CVD risk through disease activity modification (HR 1.03, 95% CI 0.80 to 1.32).

CONCLUSIONS

MTX use in RA was associated with a reduced risk of CVD events, particularly HF-related hospitalisations. These associations were not mediated through reductions in RA disease activity, suggesting alternative MTX-related mechanisms may modify CVD risk in this population.

Validity of ICD-10-CM diagnoses to identify hospitalizations for serious infections among patients treated with biologic therapies

PURPOSE

Identifying hospitalizations for serious infections among patients dispensed biologic therapies within healthcare databases is important for post-marketing surveillance of these drugs. We determined the positive predictive value (PPV) of an ICD-10-CM-based diagnostic coding algorithm to identify hospitalization for serious infection among patients dispensed biologic therapy within the FDA's Sentinel Distributed Database.

METHODS

We identified health plan members who met the following algorithm criteria: (1) hospital ICD-10-CM discharge diagnosis of serious infection between July 1, 2016 and August 31, 2018; (2) either outpatient/emergency department infection diagnosis or outpatient antimicrobial treatment within 7 days prior to hospitalization; (3) inflammatory bowel disease, psoriasis, or rheumatological diagnosis within 1 year prior to hospitalization, and (4) were dispensed outpatient biologic therapy within 90 days prior to admission. Medical records were reviewed by infectious disease clinicians to adjudicate hospitalizations for serious infection. The PPV (95% confidence interval [CI]) for confirmed events was determined after further weighting by the prevalence of the type of serious infection in the database.

RESULTS

Among 223 selected health plan members who met the algorithm, 209 (93.7% [95% CI, 90.1%-96.9%]) were confirmed to have a hospitalization for serious infection. After weighting by the prevalence of the type of serious infection, the PPV of the ICD-10-CM algorithm identifying a hospitalization for serious infection was 80.2% (95% CI, 75.3%-84.7%).

CONCLUSIONS

The ICD-10-CM-based algorithm for hospitalization for serious infection among patients dispensed biologic therapies within the Sentinel Distributed Database had 80% PPV for confirmed events and could be considered for use within pharmacoepidemiologic studies.

Accuracy of Administrative Database Algorithms for Hospitalized Pneumonia in Adults: a Systematic Review

BACKGROUND

Administrative data algorithms (ADAs) to identify pneumonia cases are commonly used in the analysis of pneumonia burden, trends, etiology, processes of care, outcomes, health care utilization, cost, and response to preventative and therapeutic interventions. However, without a good understanding of the validity of ADAs for pneumonia case identification, an adequate appreciation of this literature is difficult. We systematically reviewed the quality and accuracy of published ADAs to identify adult hospitalized pneumonia cases.

METHODS

We reviewed the Medline, EMBase, and Cochrane Central databases through May 2020. All studies describing ADAs for adult hospitalized pneumonia and at least one accuracy statistic were included. Investigators independently extracted information about the sampling frame, reference standard, ADA composition, and ADA accuracy.

RESULTS

Thirteen studies involving 24 ADAs were analyzed. Compliance with a 38-item study-quality assessment tool ranged from 17 to 29 (median, 23; interquartile range [IQR], 20 to 25). Study setting, design, and ADA composition varied extensively. Inclusion criteria of most studies selected for high-risk populations and/or increased pneumonia likelihood. Reference standards with explicit criteria (clinical, laboratorial, and/or radiographic) were used in only 4 ADAs. Only 2 ADAs were validated (one internally and one externally). ADA positive predictive values ranged from 35.0 to 96.5% (median, 84.8%; IQR, 65.3 to 89.1%). However, these values are exaggerated for an unselected patient population because pneumonia prevalences in the study cohorts were very high (median, 66%; IQR, 46 to 86%). ADA sensitivities ranged from 31.3 to 97.8% (median, 65.1%; IQR 52.5-72.4).

DISCUSSION

ADAs for identification of adult pneumonia hospitalizations are highly heterogeneous, poorly validated, and at risk for misclassification bias. Greater standardization in reporting ADA accuracy is required in studies using pneumonia ADA for case identification so that results can be properly interpreted.

Frailty and Risk of Serious Infections in Biologic-treated Patients With Inflammatory Bowel Diseases

BACKGROUND

Identifying biologic-treated patients with inflammatory bowel diseases (IBDs) at higher risk of serious infections is a priority. We conducted a retrospective cohort study evaluating frailty and risk of serious infections in biologic-treated patients with IBD.

METHODS

Using an administrative claims database, we identified biologic-treated patients with IBD between 2014 and 2018 with follow-up 1 year before and after treatment initiation. Using a validated claims-based hospital frailty risk scoring system, patients were classified as frail and nonfrail. We compared the risk of serious infections (infections requiring hospitalization) between frail and nonfrail patients using Cox proportional hazard analysis adjusting for age, comorbidities, disease characteristics, health care utilization, use of corticosteroids, immunomodulators, and opiates.

RESULTS

We included 5987 biologic-treated patients with IBD (4881 on TNFα antagonists, 1106 on vedolizumab), of whom 2350 (39.3%) were classified as frail; over 7115 person-years of follow-up was included, and 520 patients developed serious infection. Frailty was not associated with increased risk of serious infection (adjusted hazard ratio [aHR], 1.12; 95% CI, 0.93-1.36), whereas advanced age (older than 60 years), high comorbidity burden, corticosteroid use, opiate use, and prior serious infection were associated with increased risk of serious infection. On stratified analysis, frailty was associated with increased risk of serious infections in vedolizumab-treated patients (aHR, 1.69; 95% CI, 1.03-2.79) but not in TNFα antagonist-treated patients (aHR, 1.03; 95% CI, 0.83-1.27).

CONCLUSIONS

In biologic-treated patients with IBD, frailty assessed using a claims-based frailty index was not independently associated with increased risk of serious infections. Future studies evaluating objective and biological measures of frailty are warranted to risk-stratify older patients with IBD.

Hospitalized Infections in Lupus: A Nationwide Study of Types of Infections, Time Trends, Health Care Utilization, and In-Hospital Mortality

OBJECTIVE

To examine the time trends in hospitalized infections in patients with systemic lupus erythematosus (SLE), and the factors associated with health care utilization and in-hospital mortality.

METHODS

US National Inpatient Sample data from 1998-2016 were used to examine the epidemiology, time trends, and outcomes of 5 common hospitalized infections in patients with SLE, namely, pneumonia, sepsis/bacteremia, urinary tract infection (UTI), skin and soft tissue infections (SSTIs), and opportunistic infections (OIs). Time trends were compared using the Cochran-Armitage test. Multivariable-adjusted logistic regression models were used to examine the factors associated with health care utilization (hospital stay >3 days, hospital charges above the median, or discharge to a nonhome setting) and in-hospital mortality.

RESULTS

Hospitalization rates per 100,000 claims among SLE patients in 1998-2000 versus in 2015-2016 were as follows: for OIs, 1.13 versus 1.61 (1.2-fold increase); for SSTIs, 4.78 versus 12.2 (2.5-fold increase); for UTI, 1.94 versus 6.12 (3.2-fold increase); for pneumonia, 15.09 versus 17.05 (1.1-fold increase); and for sepsis, 6.31 versus 39.64 (6.3-fold increase). In 2011-2012, sepsis surpassed pneumonia as the most common hospitalized infection in patients with SLE. In multivariable-adjusted models, a diagnosis of sepsis, older age, a Deyo-Charlson common comorbidities score of ≥2, having Medicare or Medicaid insurance, and urban hospital location were significantly associated with increased odds of in-hospital mortality and with all health care utilization outcomes. African American race was significantly associated with increased odds of health care utilization.

CONCLUSION

The results of this study indicate that the rates of hospitalized infections increased over time in patients with SLE, and that pneumonia was surpassed by sepsis as the most common hospitalized infection. In addition, associations of risk factors with poorer outcomes were identified. These findings may help inform patients, providers, and policy makers with regard to the burden of infection in SLE, and could lead to interventions/pathways to improve outcomes.

Hospitalized Infections in People With Osteoarthritis: A National US Study

OBJECTIVE

To study the incidence, time trends, and outcomes of serious infections in people with osteoarthritis (OA).

METHODS

We used 1998-2016 US National Inpatient Sample (NIS) data. Using recommended weights, we examined the epidemiology of 5 types of serious infections requiring hospitalization in people with OA (opportunistic infections [OIs], skin and soft tissue infections [SSTIs], urinary tract infections [UTIs], pneumonia, and sepsis/bacteremia). We performed multivariable-adjusted logistic regression analyses to analyze factors associated with healthcare utilization (hospital charges, length of hospital stay, discharge to nonhome setting), and in-hospital mortality.

RESULTS

Of all serious infection hospitalizations, 46,708,154 were without OA and 3,258,416 had OA. People with OA were 16.4 years older, more likely to be female (52% vs 65%), White (59% vs 70%), have a Deyo-Charlson Comorbidity Index (DCCI) ≥ 2 (42% vs 51%), receive Medicare (54% vs 80%), and less likely to receive care at an urban teaching hospital (45% vs 39%). Serious infection rates per 100,000 NIS hospitalizations increased from the study period of 1998-2000 to 2015-2016: OI (from 4.5 to 7.2); SSTI (from 48.4 to 145.9); UTI (from 8.4 to 104.6); pneumonia (from 164.0 to 224.3); and sepsis (from 39.4 to 436.3). In multivariable-adjusted analyses, older age, higher DCCI, sepsis, northeast region, urban hospital, and medium or large hospital bed size were significantly associated with higher healthcare utilization outcomes and in-hospital mortality; Medicaid insurance, non-White race, and female sex were significantly associated with higher healthcare utilization.

CONCLUSION

Serious infection rates have increased in people with OA. Association of demographic, clinic, and hospital variables with serious infection outcomes identifies potential targets for future interventions.

Serious infections in people with systemic sclerosis: a national US study

Objective

To study incidence, time trends, and outcomes of serious infections in systemic sclerosis (SSc).

Methods

We used the 1998–2016 US National Inpatient Sample data. We examined the epidemiology, time trends, and outcomes of five serious infections (opportunistic infections (OI), skin and soft tissue infections (SSTI), urinary tract infection (UTI), pneumonia, and sepsis/bacteremia) in hospitalized people with SSc. We performed multivariable-adjusted logistic regression analyses to analyze independent association of factors with healthcare utilization (hospital charges, length of hospital stay, discharge to non-home setting) and in-hospital mortality.

Results

There were 49,904,955 hospitalizations with serious infections in people without SSc and 61,615 in those with SSc. During 1998–2016, the most common serious infections in SSc were pneumonia (45%), sepsis (32%), SSTI (19%), UTI (3%), and OI (3%). In 2013–2014, sepsis surpassed pneumonia as the most common serious infection; by 2015–2016, sepsis was 1.8 times more common than pneumonia. Over the study period, hospital charges increased, while length of hospital stay and in-hospital mortality decreased, overall and for each serious infection. Multivariable-adjusted analyses showed that sepsis, age ≥ 80 years, and Deyo-Charlson score ≥ 2 were associated with significantly higher odds of healthcare utilization and in-hospital mortality, and Medicare or Medicaid insurance payer, Northeast location, urban teaching or non-teaching hospital, and medium or large hospital bed size with significantly higher odds of healthcare utilization.

Conclusions

Outcomes in people with SSc hospitalized with serious infections have improved over time, except higher hospital charges. Identification of factors associated with higher healthcare utilization and in-hospital mortality allows for developing interventions to improve outcomes.

Epidemiology, Time Trends, and Outcomes of Serious Infections in Patients With Vasculitis: A Nineteen-Year National Study

OBJECTIVE

To examine the epidemiology, time trends, and outcomes and types of serious infections in people with vasculitis in the US.

METHODS

We identified people with vasculitis who were hospitalized with a primary diagnosis of pneumonia, sepsis/bacteremia, urinary tract infection (UTI), skin and soft tissue infections, or opportunistic infections in the 1998-2016 US National Inpatient Sample. We used adjusted logistic regression to examine the predictors of a hospital stay >3 days, total hospital charges greater than the median, discharge to a non-home setting, and in-hospital mortality.

RESULTS

We noted 111,345 serious infections in patients with vasculitis (14% of all vasculitis hospitalizations). Among the patients, the mean age was 67.3 years, the Deyo-Charlson comorbidity index score was ≥2 in 54%, 37% were male, and 67% were White. The serious infection hospitalization rate per 100,000 US National Inpatient Sample claims in 1998-2000 versus 2015-2016 (and rates of increase) in patients with vasculitis was as follows: overall, 12.14 versus 25.15 (2.1-fold); opportunistic infections, 0.78 versus 0.83 (1.1-fold); skin and soft tissue infections, 1.38 versus 2.52 (1.8-fold); UTI, 0.35 versus 1.48 (4.2-fold); pneumonia, 7.10 versus 6.23 (0.9-fold); and sepsis, 2.53 versus 14.10 (5.6-fold). Pneumonia was the most common serious infection in 1998-2000 (58%) versus sepsis in 2015-2016 (56%). Sepsis, older age, Deyo-Charlson comorbidity index score of ≥2, urban hospital, or medium/large hospital (by number of beds) were associated with higher health care utilization and in-hospital mortality rates; Northeast region and Medicare and Medicaid payer type were associated with higher rates of health care utilization.

CONCLUSION

Serious infection hospitalization rates are increasing in patients with vasculitis except among those with pneumonia. Sepsis was the most common serious infection in 2015-2016. Several patient and hospital factors are associated with health care utilization and mortality in serious infection hospitalization in vasculitis.

Serious infections in people with polymyalgia rheumatica (PMR) or giant cell arteritis (GCA): a time-trend national US study

OBJECTIVE

To assess incidence, time-trends, and outcomes of serious infections in people with polymyalgia rheumatica (PMR) or giant cell arteritis (GCA).

METHODS

We examined the 1998-2016 US National Inpatient Sample for serious infections in PMR or GCA, namely, opportunistic infections (OI), skin and soft tissue infections (SSTI), urinary tract infection (UTI), pneumonia, and sepsis/bacteremia. Multivariable-adjusted logistic regressions assessed association of the type of infection, demographics, comorbidity, and hospital characteristics with healthcare utilization and mortality.

RESULTS

Hospitalized with serious infections, those with PMR or GCA were 2 decades older than people without PMR or GCA, and more likely to be female or white or have higher Deyo-Charlson index score or higher income. Sepsis rates in the general population, PMR, and GCA cohorts were 10.2%, 17.7%, and 18.9% in 2015-2016, respectively. Incidence rates of serious infections/100,000 NIS claims in PMR and GCA in 2015-2016 were as follows (rounded off): OI, < 1 and < 1; SSTI, 4 and 1; UTI, 4 and 1; pneumonia, 9 and 2; and sepsis, 20 and 4, respectively. Sepsis surpassed pneumonia as the most common serious infection in 2011-2012. In multivariable-adjusted analyses in the PMR cohort, sepsis, female sex, Deyo-Charlson comorbidity score ≥ 2, Medicare or Medicaid insurance, urban hospital location, and large hospital bed size were associated with significantly higher healthcare utilization and/or in-hospital mortality. Similar associations were noted in the GCA cohort.

CONCLUSIONS

Incidence of serious infections, especially sepsis, increased in both PMR and GCA cohorts over time. Interventions to improve serious infection outcomes in PMR/GCA are needed. Key Points • PMR/GCA patients with hospitalized serious infections were 2 decades older than the general population. • Sepsis surpassed pneumonia as the commonest hospitalized serious infection in PMR/GCA in 2011-2012. • Sepsis, female sex, comorbidity, Medicare/Medicaid insurance, and urban location were associated with higher healthcare utilization and in-hospital mortality.

Comparing the burdens of opportunistic infections among patients with systemic rheumatic diseases: a nationally representative cohort study

Objective

To estimate and compare the burdens of opportunistic infections and herpes zoster in real-world practice among patients with various systemic rheumatic diseases.

Methods

This 13-year cohort study used national health insurance data to compare the incidence rates (IRs) of nine opportunistic infections among patients with five rheumatic diseases. The analyses were stratified according to follow-up duration using Poisson regression, and Cox models were used to compare the risk of first opportunistic infection.

Results

During 2000–2013, we identified 76,966 patients who had polymyositis/dermatomyositis (PM/DM, 2270 cases), systemic lupus erythematosus (SLE, 15,961 cases), systemic sclerosis (SSc, 2071 cases), rheumatoid arthritis (RA, 38,355 cases), or primary Sjögren’s syndrome (pSS, 18,309 cases). The IR of opportunistic infections was highest for PM/DM cases (61.3/1000 person-years, 95% confidence interval [CI] 56.6–66.2), followed by SLE cases (43.1/1000 person-years, 95% CI 41.7–44.5), SSc cases (31.6/1000 person-years, 95% CI 28.3–35.1), RA cases (25.0/1000 person-years, 95% CI 24.4–25.7), and pSS cases (24.1/1000 person-years, 95% CI 23.1–25.2). Multivariable Cox analysis revealed that, relative to SLE, PM/DM was associated with a significantly higher risk of opportunistic infections (hazard ratio 1.18, 95% CI 1.08–1.29). The risk of opportunistic infections was highest during the first year after the diagnosis of all five rheumatic diseases.

Conclusions

The risk of opportunistic infection was highest for PM/DM, followed by SLE, SSc, RA, and pSS. Careful observation and preventive therapy for opportunistic infections may be warranted in selected PM/DM patients, especially during the first year after the diagnosis.

Long-acting Opioid Use and the Risk of Serious Infections: A Retrospective Cohort Study

BACKGROUND

Although evidence from animal and human studies indicates opioid analgesics increase susceptibility to infections, it is unclear whether the risk varies by specific opioid. We compared the risk of serious infection among patients initiating long-acting opioid analgesics with and without previously reported immunosuppressive properties.

METHODS

We conducted a retrospective cohort study of Tennessee Medicaid enrollees age ≥18 years initiating long-acting opioids (1995-2015). Hospitalizations for serious infection were identified using validated coding algorithms. We used multivariable Poisson regression models to calculate adjusted incidence rate ratios (aIRR) and 95% confidence intervals (CI) to compare the infection risk among patients using long-acting opioids with known immunosuppressive properties (morphine, fentanyl, methadone) to the infection risk among patients using long-acting opioids without known immunosuppressive properties (oxycodone, oxymorphone, tramadol) accounting for demographics, opioid dose, comorbidities and pain conditions, medication use, frailty indicators, and healthcare encounter history using exposure propensity scores. We further compared users of individual long-acting opioids to long-acting morphine users (considered the prototypical immunosuppressive opioid).

RESULTS

Among the 61 240 patients initiating opioids with immunosuppressive properties and 22 811 patients initiating opioids without immunosuppressive properties, we identified 1906 serious infections. Nonimmunosuppressive opioid users had a lower rate of infections than immunosuppressive opioid users (aIRR:0.78 [CI: 0.66-0.91]). Among individual opioids, oxycodone users had a lower rate of infection than morphine users (aIRR:0.73 [CI: 0.60-0.89]). There were no significant differences in the infection risk between other opioids and morphine.

CONCLUSION

The risk of serious infections among long-acting opioid users varies by opioid type. Providers should carefully consider the risk of serious infections when making pain management decisions.

Comparative risks of chronic inhaled corticosteroids and macrolides for bronchiectasis

Introduction

Non-cystic fibrosis (CF) bronchiectasis (“bronchiectasis”) is a chronic airway disease for which little data exist to inform treatment decisions. We sought to compare the risks of respiratory infections in chronic users of inhaled corticosteroids (ICSs) versus macrolide monotherapy.

Methods

We identified a cohort of US Medicare enrollees with a bronchiectasis diagnosis (International Classification of Diseases, Ninth Revision, Clinical Modification code 494.0 or 494.1) between 2006 and 2014, excluding CF. We defined chronic new use as the first ≥28-day prescription of ICS therapy or macrolide monotherapy. We compared the characteristics of the exposure cohorts using standardised mean differences (SMDs) and computed a propensity score (PS) to account for treatment differences. The risks of acute exacerbation, hospitalised respiratory infection, all-cause hospitalisation and mortality were compared using PS decile-adjusted Cox regression models.

Results

We identified 83 589 new users of ICSs and 6500 new users of macrolides from 285 043 included Medicare enrollees with bronchiectasis. The crude incidence of hospitalised respiratory infection was 12.6 (ICS therapy) and 10.3 (macrolide monotherapy) per 100 patient-years. The PS-adjusted HRs comparing ICS with macrolide new users were 1.39 (95% CI 1.23–1.57) for hospitalised respiratory infection, 1.56 (95% 1.49–1.64) for acute exacerbation and 1.09 (95% 0.95–1.25) for mortality.

Interpretation

Among patients with bronchiectasis, the use of ICSs was associated with an increased risk of hospitalised respiratory infections compared with macrolide monotherapy.

Improved Quality of Life With Anti-TNF Therapy Compared With Continued Corticosteroid Utilization in Crohn's Disease

BACKGROUND

Corticosteroids (CS) and anti-TNF drugs are used to treat Crohn's disease (CD). In this study, we assessed the net health benefit of initiating anti-TNF therapy relative to additional CS use in CD using a novel combination of a retrospective cohort study and a simulation model.

METHODS

Using Medicaid data from 2001 to 2005 and Medicare data from 2006 to 2013, beneficiaries were identified with CD and CS use who subsequently received either an anti-TNF or reached a cumulative dose of >3000 mg CS during the year. By using overall and latent class-specific remission-time equivalent (RTE) estimates derived from discrete-choice experiments, mean 12-month cumulative RTEs were calculated after propensity score adjustment for baseline characteristics. A Markov model was constructed using transition probabilities derived from the retrospective cohort to perform additional sensitivity analyses of RTE estimates, analytic assumptions, and transition probabilities. Cumulative RTEs were calculated via Monte Carlo simulation in this model.

RESULTS

In the retrospective cohort, 1563 new anti-TNF initiators and 1563 propensity score-matched prolonged CS users were identified. Anti-TNF use was associated with greater mean RTEs at the end of 1 year (5.34 vs 4.54, incremental benefit: 0.79; 95% CI, 0.53-1.07). This benefit persisted in all latent classes. In the Markov model, anti-TNF therapy was the preferred strategy, and the results were robust in multiple sensitivity analysis and latent class analysis.

CONCLUSIONS

In both a retrospective cohort study and a simulation model, anti-TNF use was associated with improved quality of life, measured as RTEs, when compared with continued CS utilization for CD.

Validation of discharge diagnosis codes to identify serious infections among middle age and older adults

OBJECTIVES

Hospitalisations for serious infections are common among middle age and older adults and frequently used as study outcomes. Yet, few studies have evaluated the performance of diagnosis codes to identify serious infections in this population. We sought to determine the positive predictive value (PPV) of diagnosis codes for identifying hospitalisations due to serious infections among middle age and older adults.

SETTING AND PARTICIPANTS

We identified hospitalisations for possible infection among adults >=50 years enrolled in the Tennessee Medicaid healthcare programme (2008-2012) using International Classifications of Diseases, Ninth Revision diagnosis codes for pneumonia, meningitis/encephalitis, bacteraemia/sepsis, cellulitis/soft-tissue infections, endocarditis, pyelonephritis and septic arthritis/osteomyelitis.

DESIGN

Medical records were systematically obtained from hospitals randomly selected from a stratified sampling framework based on geographical region and hospital discharge volume.

MEASURES

Two trained clinical reviewers used a standardised extraction form to abstract information from medical records. Predefined algorithms served as reference to adjudicate confirmed infection-specific hospitalisations. We calculated the PPV of diagnosis codes using confirmed hospitalisations as reference. Sensitivity analyses determined the robustness of the PPV to definitions that required radiological or microbiological confirmation. We also determined inter-rater reliability between reviewers.

RESULTS

The PPV of diagnosis codes for hospitalisations for infection (n=716) was 90.2% (95% CI 87.8% to 92.2%). The PPV was highest for pneumonia (96.5% (95% CI 93.9% to 98.0%)) and cellulitis (91.1% (95% CI 84.7% to 94.9%)), and lowest for meningitis/encephalitis (50.0% (95% CI 23.7% to 76.3%)). The adjudication reliability was excellent (92.7% agreement; first agreement coefficient: 0.91). The overall PPV was lower when requiring microbiological confirmation (45%) and when requiring radiological confirmation for pneumonia (79%).

CONCLUSIONS

Discharge diagnosis codes have a high PPV for identifying hospitalisations for common, serious infections among middle age and older adults. PPV estimates for rare infections were imprecise.

Validation of an algorithm to identify heart failure hospitalisations in patients with diabetes within the veterans health administration

OBJECTIVES

We aimed to validate an algorithm using both primary discharge diagnosis (International Classification of Diseases Ninth Revision (ICD-9)) and diagnosis-related group (DRG) codes to identify hospitalisations due to decompensated heart failure (HF) in a population of patients with diabetes within the Veterans Health Administration (VHA) system.

DESIGN

Validation study.

SETTING

Veterans Health Administration-Tennessee Valley Healthcare System PARTICIPANTS: We identified and reviewed a stratified, random sample of hospitalisations between 2001 and 2012 within a single VHA healthcare system of adults who received regular VHA care and were initiated on an antidiabetic medication between 2001 and 2008. We sampled 500 hospitalisations; 400 hospitalisations that fulfilled algorithm criteria, 100 that did not. Of these, 497 had adequate information for inclusion. The mean patient age was 66.1 years (SD 11.4). Majority of patients were male (98.8%); 75% were white and 20% were black.

PRIMARY AND SECONDARY OUTCOME MEASURES

To determine if a hospitalisation was due to HF, we performed chart abstraction using Framingham criteria as the referent standard. We calculated the positive predictive value (PPV), negative predictive value (NPV), sensitivity and specificity for the overall algorithm and each component (primary diagnosis code (ICD-9), DRG code or both).

RESULTS

The algorithm had a PPV of 89.7% (95% CI 86.8 to 92.7), NPV of 93.9% (89.1 to 98.6), sensitivity of 45.1% (25.1 to 65.1) and specificity of 99.4% (99.2 to 99.6). The PPV was highest for hospitalisations that fulfilled both the ICD-9 and DRG algorithm criteria (92.1% (89.1 to 95.1)) and lowest for hospitalisations that fulfilled only DRG algorithm criteria (62.5% (28.4 to 96.6)).

CONCLUSIONS

Our algorithm, which included primary discharge diagnosis and DRG codes, demonstrated excellent PPV for identification of hospitalisations due to decompensated HF among patients with diabetes in the VHA system.

Fludrocortisone Is Associated With a Higher Risk of All-Cause Hospitalizations Compared With Midodrine in Patients With Orthostatic Hypotension

BACKGROUND

Orthostatic hypotension causes ≈80 000 hospitalizations per year in the United States. Treatments for orthostatic hypotension include fludrocortisone, a mineralocorticoid analog that promotes sodium reabsorption; and midodrine, an α-1 adrenergic agonist that is a direct vasoconstrictor. Although both medications are used to treat orthostatic hypotension, few studies have compared their relative safety.

METHODS AND RESULTS

We compared incidence rates of hospitalizations for all causes, and for congestive heart failure between users of fludrocortisone and users of midodrine in a retrospective cohort study of Tennessee Medicaid adult enrollees (1995-2009). Adjusted incidence rate ratios were calculated using negative binomial regression models. Subgroup analyses based on history of congestive heart failure were conducted. We studied 1324 patients initiating fludrocortisone and 797 patients initiating midodrine. Compared with fludrocortisone users, midodrine users had higher prevalence of cardiovascular conditions. Incidence rates of all-cause hospitalizations for fludrocortisone and midodrine users were 1489 and 1330 per 1000 person-years, respectively (adjusted incidence-rate ratio 1.20, 95% confidence interval, 1.02-1.40). The respective rates of heart failure-related hospitalization were 76 and 84 per 1000 person-years (adjusted incidence-rate ratio: 1.33, 95% confidence interval, 0.79-2.56). Among patients with a history of congestive heart failure, the rates of all-cause hospitalization for fludrocortisone and midodrine were 2448 and 1820 per 1000 person-years (adjusted incidence-rate ratio: 1.42, 95% confidence interval, 1.07-1.90), and the respective rates of heart failure exacerbation-related hospitalizations were 297 and 263 per 1000 person-years (adjusted incidence-rate ratio: 1.48, 95% confidence interval, 0.69-3.16).

CONCLUSIONS

Compared with users of midodrine, users of fludrocortisone had higher rates of all-cause hospitalizations, especially among patients with congestive heart failure.

Identification of Acute Decompensated Heart Failure Hospitalizations Using Administrative Data

Hospitalization for acute decompensated heart failure (ADHF) is an important outcome in clinical trials and heart failure registries; however, the optimal strategy to identify these hospitalizations using International Classification of Diseases, Ninth Revision (ICD-9) codes is uncertain. We sought to identify diagnostic codes that improve ascertainment of ADHF hospitalizations. Heart failure-related ICD-9 principal discharge codes were used to identify 2,202 hospitalizations within the Minneapolis Veterans Affairs Medical Center from 2009 to 2014. Two independent reviewers adjudicated 447 of these hospitalizations to determine the accuracy of each code. We then applied our findings to an unadjusted nationwide sample containing the same ICD-9 codes of interest, from which overall positive predictive value (PPV), sensitivity, and accuracy were calculated. Use of 428.x alone resulted in a PPV of 91.3% (95% confidence interval [CI] 91.0 to 91.7), sensitivity of 97.5% (95% CI 97.3 to 97.6), and accuracy of 89.7% (95% CI 89.4 to 90.0). Combining 428.x with 402.x1, 404.x1, 415, and 518.4 resulted in improved sensitivity (99.2%; 95% CI 99.0 to 99.3) and accuracy (90.7%; 95% CI 90.4 to 91.1) while maintaining a PPV of 91.1% (95% CI 90.7 to 91.4). Excluding chronic heart failure codes (428.22, 428.32, and 428.42) from the proposed strategy resulted in an improvement of PPV to 92.3% (95% CI 92.0 to 92.6), although sensitivity and accuracy decreased to 96.6% (95% CI 96.3 to 96.8) and 90.0% (95% CI 89.6 to 90.3), respectively. In conclusion, a combination of codes including 428.x, 402.x1, 404.x1, 415, and 518.4 improves sensitivity and overall accuracy in ascertaining ADHF events compared with 428.x alone. This strategy could be further improved by manual adjudication of chronic heart failure codes.

Sepsis surveillance from administrative data in the absence of a perfect verification

PURPOSE

Past studies of sepsis epidemiology did not address misclassification bias due to imperfect verification of sepsis detection methods to estimate the true prevalence.

METHODS

We examined 273,126 hospitalizations from 2008 to 2012 at a tertiary-care center to develop surveillance-aimed sepsis detection criteria, based on the presence of the sepsis-explicit International Classification of Diseases, Ninth Revision, Clinical Modification codes (995.92 or 785.52), blood culture orders, and antibiotics administration. We used Bayesian multinomial latent class models to estimate the true prevalence of sepsis, while adjusting for the imperfect sensitivity and specificity and the conditional dependence among the individual criteria.

RESULTS

The apparent annual prevalence of sepsis hospitalizations based on explicit International Classification of Diseases, Ninth Revision, Clinical Modification codes were 1.5%, 1.4%, 1.6%, 2.2%, and 2.5% for the years 2008 to 2012. Bayesian posterior estimates for the true prevalence of sepsis suggested that it remained stable from 2008, 19.2% (95% credible interval [CI]: 17.9%, 22.9%), to 2012, 17.8% (95% CI: 16.8%, 20.2%). The sensitivity of sepsis-explicit codes, however, increased from 7.6% (95% CI: 6.4%, 8.4%) in 2008 to 13.8% (95% CI: 12.2%, 14.9%) in 2012.

CONCLUSIONS

The true prevalence of sepsis remained high, but stable despite an increase in the sensitivity of sepsis-explicit codes in administrative data.

Opioid Analgesics and the Risk of Serious Infections Among Patients With Rheumatoid Arthritis: A Self-Controlled Case Series Study

OBJECTIVE

Animal studies and in vitro human studies suggest that certain opioid analgesics impair crucial immune functions. This study was undertaken to determine whether opioid use is associated with increased risk of serious infection in patients with rheumatoid arthritis (RA).

METHODS

We conducted a self-controlled case series analysis on a retrospective cohort of 13,796 patients with RA enrolled in Tennessee Medicaid in 1995-2009. Within-person comparisons of the risk of hospitalization for serious infection during periods of opioid use versus non-use were performed using conditional Poisson regression. Fixed confounders were accounted for by design; time-varying confounders included age and use of disease-modifying antirheumatic drugs, glucocorticoids, and proton-pump inhibitors. In additional analyses, risks associated with new opioid use, use of opioids known to have immunosuppressive properties, use of long-acting opioids, and different opioid dosages were assessed. Sensitivity analyses were performed to account for potential protopathic bias and confounding by indication.

RESULTS

Among 1,790 patients with RA who had at least 1 hospitalization for serious infection, the adjusted incidence rate of serious infection was higher during periods of current opioid use compared to non-use, with an incidence rate ratio (IRR) of 1.39 (95% confidence interval [95% CI] 1.19-1.62). The incidence rate was also higher during periods of long-acting opioid use, immunosuppressive opioid use, and new opioid use compared to non-use (IRR 2.01 [95% CI 1.52-2.66], IRR 1.72 [95% CI 1.33-2.23], and IRR 2.38 [95% CI 1.65-3.42], respectively). Results of sensitivity analyses were consistent with the main findings.

CONCLUSION

In within-person comparisons of patients with RA, opioid use was associated with an increased risk of hospitalization for serious infection.

National Lupus Hospitalization Trends Reveal Rising Rates of Herpes Zoster and Declines in Pneumocystis Pneumonia

OBJECTIVE

Infection is a leading cause of morbidity and mortality in systemic lupus erythematosus (SLE). Therapeutic practices have evolved over the past 15 years, but effects on infectious complications of SLE are unknown. We evaluated trends in hospitalizations for severe and opportunistic infections in a population-based SLE study.

METHODS

Data derive from the 2000 to 2011 United States National Inpatient Sample, including individuals who met a validated administrative definition of SLE. Primary outcomes were diagnoses of bacteremia, pneumonia, opportunistic fungal infection, herpes zoster, cytomegalovirus, or pneumocystis pneumonia (PCP). We used Poisson regression to determine whether infection rates were changing in SLE hospitalizations and used predictive marginals to generate annual adjusted rates of specific infections.

RESULTS

We identified 361,337 SLE hospitalizations from 2000 to 2011 meeting study inclusion criteria. Compared to non-SLE hospitalizations, SLE patients were younger (51 vs. 62 years), predominantly female (89% vs. 54%), and more likely to be racial/ethnic minorities. SLE diagnosis was significantly associated with all measured severe and opportunistic infections. From 2000 to 2011, adjusted SLE hospitalization rates for herpes zoster increased more than non-SLE rates: 54 to 79 per 10,000 SLE hospitalizations compared with 24 to 29 per 10,000 non-SLE hospitalizations. Conversely, SLE hospitalizations for PCP disproportionately decreased: 5.1 to 2.5 per 10,000 SLE hospitalizations compared with 0.9 to 1.3 per 10,000 non-SLE hospitalizations.

CONCLUSIONS

Among patients with SLE, herpes zoster hospitalizations are rising while PCP hospitalizations are declining. These trends likely reflect evolving SLE treatment strategies. Further research is needed to identify patients at greatest risk for infectious complications.

Validation and optimisation of an ICD-10-coded case definition for sepsis using administrative health data

OBJECTIVE

Administrative health data are important for health services and outcomes research. We optimised and validated in intensive care unit (ICU) patients an International Classification of Disease (ICD)-coded case definition for sepsis, and compared this with an existing definition. We also assessed the definition's performance in non-ICU (ward) patients.

SETTING AND PARTICIPANTS

All adults (aged ≥ 18 years) admitted to a multisystem ICU with general medicosurgical ICU care from one of three tertiary care centres in the Calgary region in Alberta, Canada, between 1 January 2009 and 31 December 2012 were included.

RESEARCH DESIGN

Patient medical records were randomly selected and linked to the discharge abstract database. In ICU patients, we validated the Canadian Institute for Health Information (CIHI) ICD-10-CA (Canadian Revision)-coded definition for sepsis and severe sepsis against a reference standard medical chart review, and optimised this algorithm through examination of other conditions apparent in sepsis.

MEASURES

Sensitivity (Sn), specificity (Sp), positive predictive value (PPV) and negative predictive value (NPV) were calculated.

RESULTS

Sepsis was present in 604 of 1001 ICU patients (60.4%). The CIHI ICD-10-CA-coded definition for sepsis had Sn (46.4%), Sp (98.7%), PPV (98.2%) and NPV (54.7%); and for severe sepsis had Sn (47.2%), Sp (97.5%), PPV (95.3%) and NPV (63.2%). The optimised ICD-coded algorithm for sepsis increased Sn by 25.5% and NPV by 11.9% with slightly lowered Sp (85.4%) and PPV (88.2%). For severe sepsis both Sn (65.1%) and NPV (70.1%) increased, while Sp (88.2%) and PPV (85.6%) decreased slightly.

CONCLUSIONS

This study demonstrates that sepsis is highly undercoded in administrative data, thus under-ascertaining the true incidence of sepsis. The optimised ICD-coded definition has a higher validity with higher Sn and should be preferentially considered if used for surveillance purposes.

Burden of Serious Infections in Adults With Systemic Lupus Erythematosus: A National Population-Based Study, 1996-2011

OBJECTIVE

To compare rates of hospitalization for serious infections, trends in rates from 1996 to 2011, and in-hospital mortality between patients with systemic lupus erythematosus (SLE) and those without SLE in a national sample.

METHODS

We analyzed hospitalizations for pneumonia, bacteremia/sepsis, urinary tract infections, skin infections, and opportunistic infections among adults in the Nationwide Inpatient Sample. We compared rates of hospitalization yearly among patients with SLE and the general population. We also computed odds ratios (ORs) for in-hospital mortality.

RESULTS

In 1996, the estimated number of hospitalizations for pneumonia in patients with SLE was 4,382, followed by sepsis (2,305), skin infections (1,422), urinary tract infections (643), and opportunistic infections (370). Rates were much higher in patients with SLE than in those without SLE, with age-adjusted relative risks ranging from 5.7 (95% confidence interval [95% CI] 5.5-6.0) for pneumonia to 9.8 (95% CI 9.1-10.7) for urinary tract infection in 1996. Risks increased over time, so that by 2011, all relative risks exceeded 12.0. Overall risk of in-hospital mortality was higher in SLE only for opportunistic infections (adjusted OR 1.52 [95% CI 1.12-2.07]). However, in pneumonia and sepsis, mortality risks were higher in SLE among those who required mechanical ventilation.

CONCLUSION

Hospitalization rates for serious infections in SLE increased substantially between 1996 and 2011, reaching over 12 times higher than in patients without SLE in 2011. Reasons for this acceleration are unclear. In-hospital mortality was higher among patients with SLE and opportunistic infections and those with pneumonia or sepsis who required mechanical ventilation.

Low Completeness of Bacteraemia Registration in the Danish National Patient Registry

Bacteraemia is associated with significant morbidity and mortality and timely access to relia-ble information is essential for health care administrators. Therefore, we investigated the complete-ness of bacteraemia registration in the Danish National Patient Registry (DNPR) containing hospital discharge diagnoses and surgical procedures for all non-psychiatric patients. As gold standard we identified bacteraemia patients in three defined areas of Denmark (~2.3 million inhabitants) from 2000 through 2011 by use of blood culture data retrieved from electronic microbiology databases. Diagnoses coded according to the International Classification of Diseases, version 10, and surgical procedure codes were retrieved from the DNPR. The codes were categorized into seven groups, ranked a priori according to the likelihood of bacteraemia. Completeness was analysed by contin-gency tables, for all patients and subgroups. We identified 58,139 bacteraemic episodes in 48,450 patients; 37,740 episodes (64.9%) were covered by one or more discharge diagnoses within the sev-en diagnosis/surgery groups and 18,786 episodes (32.3%) had a code within the highest priority group. Completeness varied substantially according to speciality (from 17.9% for surgical to 36.4% for medical), place of acquisition (from 26.0% for nosocomial to 36.2% for community), and mi-croorganism (from 19.5% for anaerobic Gram-negative bacteria to 36.8% for haemolytic strepto-cocci). The completeness increased from 25.1% in 2000 to 35.1% in 2011. In conclusion, one third of the bacteraemic episodes did not have a relevant diagnosis in the Danish administrative registry recording all non-psychiatric contacts. This source of information should be used cautiously to iden-tify patients with bacteraemia.

A population-based study of infection-related hospital mortality in patients with dermatomyositis/polymyositis

OBJECTIVE

Dermatomyositis (DM) and polymyositis (PM) are debilitating inflammatory myopathies associated with significant mortality. We evaluated the relative contribution of infection to hospital mortality in a large population-based study of individuals with PM/DM.

METHODS

Data derive from the 2007 to 2011 Healthcare Cost and Utilization Project National Inpatient Samples and include all hospital discharges that met a validated administrative definition of PM/DM. The primary outcome was hospital mortality. Variables for infections and comorbidities were generated from discharge diagnoses using validated administrative definitions. Logistic regression was used to investigate the relationship between infection and mortality in individuals with PM/DM, adjusting for sociodemographics, utilization variables, and comorbidities. Relative risks (RRs) were calculated to compare the overall prevalence of specific infections and associated mortality in PM/DM hospitalizations with those seen in the general hospitalized population.

RESULTS

A total of 15,407 hospitalizations with PM/DM met inclusion criteria for this study and inpatient mortality was 4.5% (700 deaths). In adjusted logistic regression analyses, infection (odds ratio [OR] 3.4, 95% confidence interval [95% CI] 2.9-4.0) was the strongest predictor of hospital mortality among individuals with PM/DM. Bacterial infection (OR 3.5, 95% CI 3.0-4.1), comprised primarily of pneumonia and bacteremia, and opportunistic fungal infections (OR 2.5, 95% CI 1.5-4.0) were independently associated with hospital mortality. The overall burden of infection in hospitalizations with PM/DM was significantly increased in comparison with the general hospitalized population (RR 1.5, 95% CI 1.4-1.6).

CONCLUSION

Among hospitalized individuals with PM/DM, infection is the leading cause of mortality. Strategies to mitigate infection risk in both the clinic and hospital settings should be evaluated to improve disease outcomes.

Validity of administrative data in recording sepsis: a systematic review

Introduction

Administrative health data have been used to study sepsis in large population-based studies. The validity of these study findings depends largely on the quality of the administrative data source and the validity of the case definition used. We systematically reviewed the literature to assess the validity of case definitions of sepsis used with administrative data.

Methods

Embase and MEDLINE were searched for published articles with International Classification of Diseases (ICD) coded data used to define sepsis. Abstracts and full-text articles were reviewed in duplicate. Data were abstracted from all eligible full-text articles, including ICD-9- and/or ICD-10-based case definitions, sensitivity (Sn), specificity (Sp), positive predictive value (PPV) and negative predictive value (NPV).

Results

Of 2,317 individual studies identified, 12 full-text articles met all eligibility criteria. A total of 38 sepsis case definitions were tested, which included over 130 different ICD codes. The most common ICD-9 codes were 038.x, 790.7 and 995.92, and the most common ICD-10 codes were A40.x and A41.x. The PPV was reported in ten studies and ranged from 5.6% to 100%, with a median of 50%. Other tests of diagnostic accuracy were reported only in some studies. Sn ranged from 5.9% to 82.3%; Sp ranged from 78.3% to 100%; and NPV ranged from 62.1% to 99.7%.

Conclusions

The validity of administrative data in recording sepsis varied substantially across individual studies and ICD definitions. Our work may serve as a reference point for consensus towards an improved and harmonized ICD-coded definition of sepsis.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-015-0847-3) contains supplementary material, which is available to authorized users.

Non-viral opportunistic infections in new users of tumour necrosis factor inhibitor therapy: results of the SAfety Assessment of Biologic ThERapy (SABER) study

OBJECTIVES

To determine among patients with autoimmune diseases in the USA whether the risk of non-viral opportunistic infections (OI) was increased among new users of tumour necrosis factor α inhibitors (TNFI), when compared to users of non-biological agents used for active disease.

METHODS

We identified new users of TNFI among cohorts of rheumatoid arthritis (RA), inflammatory bowel disease and psoriasis-psoriatic arthritis-ankylosing spondylitis patients during 1998-2007 using combined data from Kaiser Permanente Northern California, two pharmaceutical assistance programmes for the elderly, Tennessee Medicaid and US Medicaid/Medicare programmes. We compared incidence of non-viral OI among new TNFI users and patients initiating non-biological disease-modifying antirheumatic drugs (DMARD) overall and within each disease cohort. Cox regression models were used to compare propensity-score and steroid- adjusted OI incidence between new TNFI and non-biological DMARD users.

RESULTS

Within a cohort of 33 324 new TNFI users we identified 80 non-viral OI, the most common of which was pneumocystosis (n=16). In the combined cohort, crude rates of non-viral OI among new users of TNFI compared to those initiating non-biological DMARD was 2.7 versus 1.7 per 1000-person-years (aHR 1.6, 95% CI 1.0 to 2.6). Baseline corticosteroid use was associated with non-viral OI (aHR 2.5, 95% CI 1.5 to 4.0). In the RA cohort, rates of non-viral OI among new users of infliximab were higher when compared to patients newly starting non-biological DMARD (aHR 2.6, 95% CI 1.2 to 5.6) or new etanercept users (aHR 2.9, 95% CI 1.5 to 5.4).

CONCLUSIONS

In the USA, the rate of non-viral OI was higher among new users of TNFI with autoimmune diseases compared to non-biological DMARD users.

A systematic review of validated methods for identifying patients with rheumatoid arthritis using administrative or claims data

PURPOSE

To review the evidence supporting the validity of billing, procedural, or diagnosis code, or pharmacy claim-based algorithms used to identify patients with rheumatoid arthritis (RA) in administrative and claim databases.

METHODS

We searched the MEDLINE database from 1991 to September 2012 using controlled vocabulary and key terms related to RA and reference lists of included studies were searched. Two investigators independently assessed the full text of studies against pre-determined inclusion criteria and extracted the data. Data collected included participant and algorithm characteristics.

RESULTS

Nine studies reported validation of computer algorithms based on International Classification of Diseases (ICD) codes with or without free-text, medication use, laboratory data and the need for a diagnosis by a rheumatologist. These studies yielded positive predictive values (PPV) ranging from 34 to 97% to identify patients with RA. Higher PPVs were obtained with the use of at least two ICD and/or procedure codes (ICD-9 code 714 and others), the requirement of a prescription of a medication used to treat RA, or requirement of participation of a rheumatologist in patient care. For example, the PPV increased from 66 to 97% when the use of disease-modifying antirheumatic drugs and the presence of a positive rheumatoid factor were required.

CONCLUSIONS

There have been substantial efforts to propose and validate algorithms to identify patients with RA in automated databases. Algorithms that include more than one code and incorporate medications or laboratory data and/or required a diagnosis by a rheumatologist may increase the PPV.

Systematic review of validation studies of the use of administrative data to identify serious infections

OBJECTIVE

To conduct a systematic review of the literature on the validation of algorithms identifying infections in administrative data for future use in populations with rheumatic diseases.

METHODS

Medline and EMBase were searched using the themes "administrative data" and "infection" between 1950 and October 2012. Inclusion criteria consisted of validation studies of administrative data identifying infections in adult populations. Article quality was assessed using a validated tool.

RESULTS

A total of 5,941 articles were identified, 90 articles underwent detailed review, and 24 studies were included. The majority (17 of 24) examined bacterial infections and 9 examined opportunistic infections. Eighteen studies were from the US and all but 4 studies used International Classification of Diseases, Ninth Revision codes. Rheumatoid arthritis patients were studied in 6 of 24 articles. The studies on bacterial infections in general reported highly variable sensitivity and positive predictive value (PPV) for the diagnosis of infections using administrative data (sensitivity range 4.4-100%, PPV range 21.7-100%). Algorithms to identify opportunistic infections similarly had a highly variable sensitivity (range 20-100%) and PPV (range 1.3-100%). Thirteen studies compared the diagnostic accuracy of different algorithms, which revealed that strategies including a comprehensive algorithm using a greater number of diagnostic codes or codes in any position had the highest sensitivity for the diagnosis of infection. Algorithms that incorporated microbiologic or pharmacy data in combination with diagnostic codes had improved PPV for identification of tuberculosis.

CONCLUSION

Algorithms for identifying infections using administrative data should be selected based on the purpose of the study, with careful consideration as to whether a high sensitivity or PPV is required.

A systematic review of validated methods for identifying heart failure using administrative data

PURPOSE

To identify and describe the validity of algorithms used to detect heart failure (HF) using administrative and claims data sources.

METHODS

A systematic review of PubMed and Iowa Drug Information Service searches of the English language was performed to identify studies published between 1990 and 2010 that evaluated the validity of algorithms for the identification of patients with HF using and claims data. Abstracts and articles were reviewed by two study investigators to determine their relevance on the basis of predetermined criteria.

RESULTS

The initial search strategy identified 887 abstracts. Of these, 499 full articles were reviewed and 35 studies included data to evaluate the validity of identifying patients with HF. Positive predictive values (PPVs) were in the acceptable to high range, with most being very high (>90%). Studies that included patients with a primary hospital discharge diagnosis of International Classification of Diseases, Ninth Revision, code 428.X had the highest PPV and specificity for HF. PPVs for this algorithm ranged from 84% to 100%. This algorithm, however, may compromise sensitivity because many HF patients are managed on an outpatient basis. The most common 'gold standard' for the validation of HF was the Framingham Heart Study criteria.

CONCLUSIONS

The algorithms and definitions used to identify HF using administrative and claims data perform well, particularly when using a primary hospital discharge diagnosis. Attention should be paid to whether patients who are managed on an outpatient basis are included in the study sample. Including outpatient codes in the described algorithms would increase the sensitivity for identifying new cases of HF.

The health services burden of heart failure: an analysis using linked population health data-sets

BACKGROUND

The burden of patients with heart failure on health care systems is widely recognised, although there have been few attempts to quantify individual patterns of care and differences in health service utilisation related to age, socio-economic factors and the presence of co-morbidities. The aim of this study was to assess the typical profile, trajectory and resource use of a cohort of Australian patients with heart failure using linked population-based, patient-level data.

METHODS

Using hospital separations (Admitted Patient Data Collection) with death registrations (Registry of Births, Deaths and Marriages) for the period 2000-2007 we estimated age- and gender-specific rates of index admissions and readmissions, risk factors for hospital readmission, mean length of stay (LOS), median survival and bed-days occupied by patients with heart failure in New South Wales, Australia.

RESULTS

We identified 29,161 index admissions for heart failure. Admission rates increased with age, and were higher for males than females for all age groups. Age-standardised rates decreased over time (256.7 to 237.7/100,000 for males and 235.3 to 217.1/100,000 for females from 2002-3 to 2006-7; p = 0.0073 adjusted for gender). Readmission rates (any cause) were 27% and 73% at 28-days and one year respectively; readmission rates for heart failure were 11% and 32% respectively. All cause mortality was 10% and 28% at 28 days and one year. Increasing age was associated with more heart failure readmissions, longer LOS and shorter median survival. Increasing age, increasing Charlson comorbidity score and male gender were risk factors for hospital readmission. Cohort members occupied 954,888 hospital bed-days during the study period (any cause); 383,646 bed-days were attributed to heart failure admissions.

CONCLUSIONS

The rates of index admissions for heart failure decreased significantly in both males and females over the study period. However, the impact on acute care hospital beds was substantial, with heart failure patients occupying almost 200,000 bed-days per year in NSW over the five year study period. The strong age-related trends highlight the importance of stabilising elderly patients before discharge and community-based outreach programs to better manage heart failure and reduce readmissions.

Geographic distribution of endemic fungal infections among older persons, United States

TOC summary: Incidence was highest for histoplasmosis and blastomycosis in the Midwest and for coccidioidomycosis in the West.

To investigate the epidemiology and geographic distribution of histoplasmosis, coccidioidomycosis, and blastomycosis in older persons in the United States, we evaluated a random 5% sample of national Medicare data from 1999 through 2008. We calculated national, regional, and state-based incidence rates and determined 90-day postdiagnosis mortality rates. We identified 776 cases (357 histoplasmosis, 345 coccidioidomycosis, 74 blastomycosis). Patient mean age was 75.7 years; 55% were male. Histoplasmosis and blastomycosis incidence was highest in the Midwest (6.1 and 1.0 cases/100,000 person-years, respectively); coccidioidomycosis incidence rate was highest in the West (15.2). On the basis of available data, for 86 (11.1%) cases, there was no patient exposure to a traditional disease-endemic area. Knowledge of areas where endemic mycosis incidence is increased may affect diagnostic or prevention measures for older adults at risk.

ADHD medications and risk of serious cardiovascular events in young and middle-aged adults

CONTEXT

More than 1.5 million US adults use stimulants and other medications labeled for treatment of attention-deficit/hyperactivity disorder (ADHD). These agents can increase heart rate and blood pressure, raising concerns about their cardiovascular safety.

OBJECTIVE

To examine whether current use of medications prescribed primarily to treat ADHD is associated with increased risk of serious cardiovascular events in young and middle-aged adults.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective, population-based cohort study using electronic health care records from 4 study sites (OptumInsight Epidemiology, Tennessee Medicaid, Kaiser Permanente California, and the HMO Research Network), starting in 1986 at 1 site and ending in 2005 at all sites, with additional covariate assessment using 2007 survey data. Participants were adults aged 25 through 64 years with dispensed prescriptions for methylphenidate, amphetamine, or atomoxetine at baseline. Each medication user (n = 150,359) was matched to 2 nonusers on study site, birth year, sex, and calendar year (443,198 total users and nonusers).

MAIN OUTCOME MEASURES

Serious cardiovascular events, including myocardial infarction (MI), sudden cardiac death (SCD), or stroke, with comparison between current or new users and remote users to account for potential healthy-user bias.

RESULTS

During 806,182 person-years of follow-up (median, 1.3 years per person), 1357 cases of MI, 296 cases of SCD, and 575 cases of stroke occurred. There were 107,322 person-years of current use (median, 0.33 years), with a crude incidence per 1000 person-years of 1.34 (95% CI, 1.14-1.57) for MI, 0.30 (95% CI, 0.20-0.42) for SCD, and 0.56 (95% CI, 0.43-0.72) for stroke. The multivariable-adjusted rate ratio (RR) of serious cardiovascular events for current use vs nonuse of ADHD medications was 0.83 (95% CI, 0.72-0.96). Among new users of ADHD medications, the adjusted RR was 0.77 (95% CI, 0.63-0.94). The adjusted RR for current use vs remote use was 1.03 (95% CI, 0.86-1.24); for new use vs remote use, the adjusted RR was 1.02 (95% CI, 0.82-1.28); the upper limit of 1.28 corresponds to an additional 0.19 events per 1000 person-years at ages 25-44 years and 0.77 events per 1000 person-years at ages 45-64 years.

CONCLUSIONS

Among young and middle-aged adults, current or new use of ADHD medications, compared with nonuse or remote use, was not associated with an increased risk of serious cardiovascular events. Apparent protective associations likely represent healthy-user bias.

Initiation of tumor necrosis factor-α antagonists and the risk of hospitalization for infection in patients with autoimmune diseases

CONTEXT

Although tumor necrosis factor (TNF)-α antagonists are increasingly used in place of nonbiologic comparator medications, their safety profile remains incomplete.

OBJECTIVES

To determine whether initiation of TNF-α antagonists compared with nonbiologic comparators is associated with an increased risk of serious infections requiring hospitalization.

DESIGN, SETTING, AND PATIENTS

Within a US multi-institutional collaboration, we assembled retrospective cohorts (1998-2007) of patients with rheumatoid arthritis (RA), inflammatory bowel disease (IBD), and psoriasis, psoriatic arthritis, or ankylosing spondylitis (psoriasis and spondyloarthropathies) combining data from Kaiser Permanente Northern California, New Jersey and Pennsylvania Pharmaceutical Assistance programs, Tennessee Medicaid, and national Medicaid/Medicare. TNF-α antagonists and nonbiologic regimens were compared in disease-specific propensity score (PS)-matched cohorts using Cox regression models with nonbiologics as the reference. Baseline glucocorticoid use was evaluated as a separate covariate.

MAIN OUTCOME MEASURE

Infections requiring hospitalization (serious infections) during the first 12 months after initiation of TNF-α antagonists or nonbiologic regimens.

RESULTS

Study cohorts included 10,484 RA, 2323 IBD, and 3215 psoriasis and spondyloarthropathies matched pairs using TNF-α antagonists and comparator medications. Overall, we identified 1172 serious infections, most of which (53%) were pneumonia and skin and soft tissue infections. Among patients with RA, serious infection hospitalization rates were 8.16 (TNF-α antagonists) and 7.78 (comparator regimens) per 100 person-years (adjusted hazard ratio [aHR], 1.05 [95% CI, 0.91-1.21]). Among patients with IBD, rates were 10.91 (TNF-α antagonists) and 9.60 (comparator) per 100 person-years (aHR, 1.10 [95% CI, 0.83-1.46]). Among patients with psoriasis and spondyloarthropathies, rates were 5.41 (TNF-α antagonists) and 5.37 (comparator) per 100 person-years (aHR, 1.05 [95% CI, 0.76-1.45]). Among patients with RA, infliximab was associated with a significant increase in serious infections compared with etanercept (aHR, 1.26 [95% CI, 1.07-1.47]) and adalimumab (aHR, 1.23 [95% CI, 1.02-1.48]). Baseline glucocorticoid use was associated with a dose-dependent increase in infections.

CONCLUSION

Among patients with autoimmune diseases, compared with treatment with nonbiologic regimens, initiation of TNF-α antagonists was not associated with an increased risk of hospitalizations for serious infections.

Initiation of rheumatoid arthritis treatments and the risk of serious infections

OBJECTIVE

In clinical trials of RA patients on traditional DMARDs, the addition of TNF-alpha antagonists increased infections compared with addition of placebo. Our objective was to compare serious infections following initiation of different RA regimens. Prior comparative studies of DMARD initiation have yielded conflicting results.

METHODS

We estimated hospitalization rates for infections following initiation of TNF-alpha antagonists, other DMARDs and oral glucocorticoids in Tennessee Medicaid-enrolled RA patients (1995-2005). Exposure time was measured using pharmacy information and infections were identified using validated definitions. Initiation of RA regimens was compared using Cox regression models with MTX as the reference. Sensitivity analyses excluded glucocorticoid users, applied a first exposure carried forward approach, restricted observations to 2002-05 and first episodes of use and explored effects of unmeasured confounders.

RESULTS

We identified 28 906 new episodes of medication use, including TNF-alpha antagonists (8%), MTX alone (15%) and glucocorticoids alone (57%). Compared with MTX initiation, TNF-alpha antagonist initiation did not significantly increase the risk of hospitalizations for pneumonia [adjusted hazard ratio (aHR) 1.61; 95% CI 0.85, 3.03] or any infection (aHR 1.31; 95% CI 0.78, 2.19). Initiation of LEF, SSZ or HCQ did not increase serious infections, compared with MTX. Both initiation and concurrent glucocorticoid use were associated with a dose-dependent increase in serious infections. Sensitivity analyses showed consistent results.

CONCLUSIONS

Compared with initiation of MTX alone, initiation of TNF-alpha antagonists was not associated with a large increase in the risk of serious infections. Glucocorticoid use was associated with a dose-dependent increase in the risk of these infections.