A systematic review of validated methods for identifying ventricular arrhythmias using administrative and claims data

Single-Level Anterolateral and Posterior Interbody Fusion Techniques are Associated With Equivalent Long-Term Lumbar Reoperations

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

This study compares reoperation rates and complications following single-level anterior lumbar interbody fusion (ALIF)/lateral lumbar interbody fusion (LLIF) and transforaminal lumbar interbody fusion (TLIF)/posterior lumbar interbody fusion (PLIF).

SUMMARY OF BACKGROUND DATA

ALIF, LLIF, TLIF, and PLIF are widely used for degenerative disc disease. Lumbar interbody fusions have high rates of reoperation, primarily related to adjacent segment pathology and pseudarthrosis.

MATERIALS AND METHODS

The PearlDiver database was queried for patients (2010-2021) who had single-level ALIF/LLIF or TLIF/PLIF with same-day, single-level posterior instrumentation. ALIF/LLIF were combined, and similarly, TLIF/PLIF were combined, given how these operations are indistinguishable from Current Procedural Terminology coding. All patients were followed for ≥2 years and excluded if they had spinal traumas, fractures, infections, or neoplasms before surgery. The two cohorts, ALIF/LLIF and TLIF/PLIF, were matched 1:1 based on age, sex, Elixhauser-comorbidity index, smoking status, and diabetes. The primary outcome was the incidence of all-cause subsequent lumbar operations. Secondary outcomes included 90-day surgical complications.

RESULTS

After 1:1 matching, each cohort contained 14,070 patients. All-cause subsequent lumbar operations were nearly identical at five-year follow-up (9.4% ALIF/LLIF vs. 9.5% TLIF/PLIF, P =0.91). Survival analysis using all-cause subsequent lumbar operations as the endpoint showed an equivalent 10-year survival rate of 86.0% (95%CI: 85.2-86.8). Within 90 days, TLIF/PLIF had more infections (1.3% vs. 1.7%, P =0.007) and dural injuries (0.2% vs. 0.4%, P =0.001). There was no difference in wound dehiscence, hardware complications, or medical complications.

CONCLUSION

As utilized in real-world clinical practice, single-level anterolateral versus posterior approaches for interbody fusion have no effect on long-term reoperation rates.

Lumbar Total Disc Replacement Leads to Increased Subsequent Facet Injections Compared to Anterolateral Lumbar Interbody Fusions

STUDY DESIGN

Retrospective Matched Cohort.

OBJECTIVE

Despite known consequences to the facet joints following lumbar total disc replacement (TDR), there is limited data on facet injection usage for persistent postoperative pain. This study uses real-world data to compare the usage of therapeutic lumbar facet injections as a measure of symptomatic facet arthrosis following single-level, stand-alone TDR vs anterolateral lumbar interbody fusion (ALIF/LLIF).

METHODS

The PearlDiver database was queried for patients (2010-2021) with lumbar degenerative disc disease who received either a single-level, stand-alone TDR or ALIF/LLIF. All patients were followed for ≥2 years and excluded if they had a history of facet injections or spinal trauma, fracture, infection, or neoplasm. The two cohorts were matched 1:1 based on age, sex, insurance, year of operation, and medical comorbidities. The primary outcome was the use of therapeutic lumbar facet injections at 1-, 2-, and 5-year follow-up. Secondary outcomes included subsequent lumbar surgeries and surgical complications.

RESULTS

After 1:1 matching, each cohort had 1203 patients. Lumbar facet injections occurred significantly more frequently in the TDR group at 1-year (6.07% vs 1.66%, P < .0001), 2-year (8.40% vs 3.74%%, P < .0001), and 5-year (11.47% vs 6.40%, P < .0001) follow-up. 5-year injection-free probability curves demonstrated an 87.1% injection-free rate for TDR vs 92.9% for ALIF/LLIF. There was no clinical difference in the incidence of subsequent lumbar surgeries or complications.

CONCLUSION

Compared with ALIF/LLIF, patients who underwent TDR received significantly more facet injections, suggesting a greater progression of symptomatic facet arthrosis. TDR was not protective against reoperations compared to ALIF/LLIF.

Revision Surgery Risk After Open Reduction and Internal Fixation Versus Acute Total Hip Arthroplasty in Geriatric Acetabular Fractures: A Nationwide Study

BACKGROUND

The aging population has contributed to a rising incidence of acetabular fractures in older patients, yet current evidence guiding surgical treatment is limited by small sample sizes. This study used a nationwide database to investigate outcomes in older patients undergoing open reduction and internal fixation (ORIF) versus acute total hip arthroplasty (THA).

METHODS

The PearlDiver database was queried for patients aged 60 years and older with an acute acetabular fracture who underwent ORIF or acute THA (2010 to 2021). ORIF patients were matched 1:1 to THA patients based on age, sex, US region, insurance plan, and Charlson Comorbidity Index score. Patients with less than 2 years of follow-up were excluded. The primary outcome was revision surgery.

RESULTS

Of 120,032 patients with an acetabular fracture, 3,768 (3.1%) underwent surgical treatment: 1,482 (39.3%) THA and 2,286 (60.7%) ORIF. Mean age was 71.0 ± 6.51 years. Mean follow-up duration was 5.2 ± 2.1 years. THA patients were slightly older (72.4 versus 70.2 years), had higher Charlson Comorbidity Index scores (3.3 versus 2.7), and had a higher percentage of female patients (62.5% versus 32.2%). After matching, 962 ORIF and 962 THA patients were included. ORIF patients had longer LOS (10.7 versus 8.1 days). ORIF patients were less likely to experience joint infections and periprosthetic fractures, but more likely to experience transfusions. The overall revision surgery rate within 10 years was 14.8% in the ORIF cohort and 6.2% in the THA cohort. In the ORIF cohort, 13.5% of patients had a delayed conversion to THA.

CONCLUSIONS

In this large national database, acute with or without internal fixation for geriatric acetabular fractures was associated with lower rates of revision surgery within 10 years when compared with a matched cohort undergoing ORIF. ORIF was associated with increased LOS, increased transfusion risk, and lower risk of joint infection and periprosthetic fracture.

LEVEL OF EVIDENCE

III.

Social Determinants of Health Mediate Racial Disparities in Cardiovascular Disease in Men With Prostate Cancer

Background

Cardiovascular disease (CVD) is a significant cause of morbidity and mortality in men with prostate cancer; however, data on racial disparities in CVD outcomes are limited.

Objectives

We quantified the disparities in CVD according to self-identified race and the role of the structural social determinants of health in mediating disparities in prostate cancer patients.

Methods

A retrospective cohort study of 3,543 prostate cancer patients treated with systemic androgen deprivation therapy (ADT) between 2008 and 2021 at a quaternary, multisite health care system was performed. The multivariable adjusted association between self-reported race (Black vs White) and incident major adverse cardiovascular events (MACE) after ADT initiation was evaluated using cause-specific proportional hazards. Mediation analysis determined the role of theme-specific and overall social vulnerability index (SVI) in explaining the racial disparities in CVD outcomes.

Results

Black race was associated with an increased hazard of MACE (HR: 1.38; 95% CI: 1.16-1.65; P < 0.001). The association with Black race was strongest for incident heart failure (HR: 1.79; 95% CI: 1.32-2.43), cerebrovascular disease (HR: 1.98; 95% CI: 1.37-2.87), and peripheral artery disease (HR: 1.76; 95% CI: 1.26-2.45) (P < 0.001). SVI, specifically the socioeconomic status theme, mediated 98% of the disparity in MACE risk between Black and White patients.

Conclusions

Black patients are significantly more likely to experience adverse CVD outcomes after systemic ADT compared with their White counterparts. These disparities are mediated by socioeconomic status and other structural determinants of health as captured by census tract SVI. Our findings motivate multilevel interventions focused on addressing socioeconomic vulnerability.

Assessing risk of recurrent small bowel obstruction after non-operative management in patients with history of intra-abdominal surgery: a population-based comprehensive analysis in Taiwan

BACKGROUND

Despite a significant 30% ten-year readmission rate for SBO patients, investigations into recurrent risk factors after non-operative management are scarce. The study aims to generate a risk factor scoring system, the 'Small Bowel Obstruction Recurrence Score' (SBORS), predicting 6-month recurrence of small bowel obstruction (SBO) after successful non-surgical management in patients who have history of intra-abdominal surgery.

METHODS

We analyzed data from patients aged ≥ 18 with a history of intra-abdominal surgery and diagnosed with SBO (ICD-9 code: 560, 568) and were successful treated non-surgically between 2004 and 2008. Participants were divided into model-derivation (80%) and validation (20%) group.

RESULTS

We analyzed 23,901 patients and developed the SBORS based on factors including the length of hospital stay > 4 days, previous operations > once, hemiplegia, extra-abdominal and intra-abdominal malignancy, esophagogastric surgery and intestino-colonic surgery. Scores > 2 indicated higher rates and risks of recurrence within 6 months (12.96% vs. 7.27%, OR 1.898, p < 0.001 in model-derivation group, 12.60% vs. 7.05%, OR 1.901, p < 0.001 in validation group) with a significantly increased risk of mortality and operative events for recurrent episodes. The SBORS model demonstrated good calibration and acceptable discrimination, with an area under curve values of 0.607 and 0.599 for the score generation and validation group, respectively.

CONCLUSIONS

We established the effective 'SBORS' to predict 6-month SBO recurrence risk in patients who have history of intra-abdominal surgery and have been successfully managed non-surgically for the initial obstruction event. Those with scores > 2 face higher recurrence rates and operative risks after successful non-surgical management.

Risk of Cardiovascular Events in Schizophrenic Patients Treated with Paliperidone Palmitate Once-Monthly Injection (PP1M): A Population-Based Retrospective Cohort Study in Taiwan

BACKGROUND

Schizophrenia is one of the leading causes of disability. Paliperidone palmitate once-monthly injection (PP1M) was developed to provide consistent drug delivery and improve medication adherence for maintenance treatment. It is well known that patients with schizophrenia have higher cardiovascular risks, however little is known about the cardiovascular risks of patients with schizophrenia treated with PP1M in Asia.

OBJECTIVE

This study aimed to estimate the incidence of cardiovascular events after initiating PP1M treatment and evaluate the cardiovascular risk associations compared with oral second-generation antipsychotics (SGAs).

METHODS

Data from Taiwan's National Health Insurance Research Database were used to identify a cohort of adult patients with schizophrenia who received any SGAs from 1 March 2012 to 31 December 2018. Patients who initiated PP1M treatment were enrolled for descriptive analysis of incidence rates. PP1M patients were propensity matched 1:1 to patients initiating a new oral SGA, for comparative analysis based on demographics, clinical characteristics and treatment history at baseline, in three-step matching procedures, following the prevalent new-user design to enhance comparability. Follow-up ended at the end of the treatment episode of index drug, death, last record available, or end of the study (31 December 2019). Study endpoints included serious cardiovascular events (including severe ventricular arrhythmia and sudden death), expanded serious cardiovascular events (which further included acute myocardial infarction and ischemic stroke), and cardiovascular hospitalizations. Risks of study endpoints between matched cohorts were compared using Cox regression.

RESULTS

Overall, 11,023 patients initiating PP1M treatment were identified (49.5% were females; mean age of 43.2 [12.2] years). Overall incidences for serious cardiovascular events, expanded serious cardiovascular events, and cardiovascular hospitalizations were 3.92, 7.88 and 51.96 per 1000 person-years, respectively. In matched cohort analysis (N = 10,115), the hazard ratios (HRs) between initiating PP1M and a new oral SGA for serious cardiovascular events, expanded serious cardiovascular events, and cardiovascular hospitalizations were 0.86 (95% confidence interval [CI] 0.55-1.36), 0.88 (95% CI 0.63-1.21), and 0.78 (95% CI 0.69-0.89), respectively.

CONCLUSION

This study reported the population-based incidence of cardiovascular events in schizophrenic patients initiating PP1M treatment. PP1M was not associated with increased risks of serious cardiovascular events but was potentially associated with lower risks of cardiovascular hospitalizations compared with oral SGAs.

Association between First-Generation Antihistamine Use in Children and Cardiac Arrhythmia and Ischemic Heart Disease: A Case-Crossover Study

Cardiotoxicity from first-generation H1-antihistamines has been debated since the 1990s. However, large-scale studies on this topic in a general pediatric population are lacking. This study aimed to assess the association between first-generation H1-antihistamine use and cardiovascular events in a nationwide pediatric population. In this case-crossover study, the main cohort included children with cardiovascular events from the National Health Insurance Service database (2008-2012 births in Korea) until 2018. The second cohort excluded children with specific birth histories or underlying cardiovascular diseases from the main cohort. Cardiovascular events of interest included cardiac arrhythmia and ischemic heart disease. Odds ratios (ORs) of cardiovascular events were estimated using conditional logistic regression models, comparing first-generation H1-antihistamine use during 0-15 days before cardiovascular events (hazard period) with use during 45-60 and 75-90 days before events (control periods). Among the participants, 1194 (59.9%) were aged 24 months to 6 years, and 1010 (50.7%) were male. Cardiovascular event risk was increased among users of first-generation H1-antihistamines (adjusted OR [aOR], 1.201; 95% confidence interval, 1.13-1.27). Significant odds of cardiovascular events persisted within 10 and 5 days (aOR, 1.25 and 1.25). In the second cohort, the association was comparable with that in the main cohort. Our findings indicate that cardiovascular event risk is increased in children who are administered first-generation H1-antihistamines.

Health Care Utilization and Costs in Systemic Therapies for Metastatic Melanoma from 2016 to 2020

BACKGROUND

Widespread implementation of immune checkpoint inhibitors (ICI) and targeted therapies for metastatic melanoma has led to a decline in melanoma-related mortality but increased healthcare costs. We aimed to determine how healthcare utilization varied by systemic, non-adjuvant melanoma treatment from 2016 to 2020.

PATIENTS AND METHODS

Adults with presumed stage IV metastatic melanoma receiving systemic therapy from 2016 to 2020 were identified in Optum, a nationwide commercial claims database. Treatment groups were nivolumab, pembrolizumab, ipilimumab+nivolumab (combination-ICI), or BRAF+MEK inhibitor (BRAFi+MEKi) therapy. Outcomes included hospitalizations, days hospitalized, emergency room (ER) visits, outpatient visits, and healthcare costs per patient per month (pppm). Multivariable regression models were used to analyze whether cost and utilization outcomes varied by treatment group, with nivolumab as reference.

RESULTS

Among 2018 adult patients with metastatic melanoma identified, mean (SD) age was 67 (15) years. From 2016 to 2020, nivolumab surpassed pembrolizumab as the most prescribed systemic melanoma therapy while combination-ICI and BRAFi+MEKi therapies remained stable. Relative to nivolumab, all other therapies were associated with increased total healthcare costs (combination-ICI: β = $47 600 pppm, 95%CI $42 200-$53 100; BRAFi+MEKi: β = $3810, 95%CI $365-$7260; pembrolizumab: β = $6450, 95%CI $4420-$8480). Combination-ICI and BRAFi+MEKi therapies were associated with more inpatient hospital days.

CONCLUSIONS

Amid the evolving landscape of systemic therapy for advanced melanoma, nivolumab monotherapy emerged as the most used and least costly systemic treatment from 2016 to 2020. Its sharp increase in use in 2018 and lower costs relative to pembrolizumab may in part be due to earlier adoption of less frequent dosing intervals.

A Literature Review: ECG-Based Models for Arrhythmia Diagnosis Using Artificial Intelligence Techniques

In the health care and medical domain, it has been proven challenging to diagnose correctly many diseases with complicated and interferential symptoms, including arrhythmia. However, with the evolution of artificial intelligence (AI) techniques, the diagnosis and prognosis of arrhythmia became easier for the physicians and practitioners using only an electrocardiogram (ECG) examination. This review presents a synthesis of the studies conducted in the last 12 years to predict arrhythmia's occurrence by classifying automatically different heartbeat rhythms. From a variety of research academic databases, 40 studies were selected to analyze, among which 29 of them applied deep learning methods (72.5%), 9 of them addressed the problem with machine learning methods (22.5%), and 2 of them combined both deep learning and machine learning to predict arrhythmia (5%). Indeed, the use of AI for arrhythmia diagnosis is emerging in literature, although there are some challenging issues, such as the explicability of the Deep Learning methods and the computational resources needed to achieve high performance. However, with the continuous development of cloud platforms and quantum calculation for AI, we can achieve a breakthrough in arrhythmia diagnosis.

Prognostic implication of premature ventricular contractions in patients without structural heart disease

AIMS

Premature ventricular contractions (PVCs) are a common form of arrhythmia associated with an unfavourable prognosis in patients with structural heart disease. However, the prognostic significance in absence of heart disease is debated. With this study, we aim to investigate whether subjects with PVC, without structural heart disease, have a worse prognosis than the general population.

METHODS AND RESULTS

Patients evaluated for PVC at a secondary care centre in Stockholm County from January 2010 to December 2016 were identified. We included patients without history of previous heart disease who had undergone echocardiography and exercise test with normal findings. Based on sex and age, we matched the PVC cohort to a four times bigger control group from the general population and compared the outcome in terms of mortality and cardiovascular morbidity during a median follow-up time of 5.2 years. We included 820 patients and 3,264 controls. Based on a non-inferiority analysis, the PVC group did not have a higher mortality than the control group (0.44, CI 0.27-0.72). Sensitivity analysis with propensity score matching confirmed this result.

CONCLUSIONS

PVC patients, who after thorough evaluation showed no signs of structural heart disease, did not have a worse prognosis when compared to an age- and sex- control group based on the general population.

Mortality Prediction Model before Surgery for Acute Mesenteric Infarction: A Population-Based Study

Surgery for acute mesenteric infarction (AMI) is associated with high mortality. This study aimed to generate a mortality prediction model to predict the 30-day mortality of surgery for AMI. We included patients ≥18 years who received bowel resection in treating AMI and randomly divided into the derivation and validation groups. After multivariable analysis, the ‘Surgery for acute mesenteric infarction mortality score’ (SAMIMS) system was generated and was including age >62-year-old (3 points), hemodialysis (2 points), congestive heart failure (1 point), peptic ulcer disease (1 point), diabetes (1 point), cerebrovascular disease (1 point), and severe liver disease (4 points). The 30-day-mortality rates in the derivation group were 4.4%, 13.4%, 24.5%, and 32.5% among very low (0 point), low (1−3 point(s)), intermediate (4−6 points), and high (7−13 points)-risk patients. Compared to the very-low-risk group, the low-risk (OR = 3.332), intermediate-risk (OR = 7.004), and high-risk groups (OR = 10.410, p < 0.001) exhibited higher odds of 30-day mortality. We identified similar results in the validation group. The areas under the ROC curve were 0.677 and 0.696 in the derivation and validation groups. Our prediction model, SAMIMS, allowed for the stratification of the patients’ 30-day-mortality risk of surgery for acute mesenteric infarction.

The Risk of Ventricular Dysrhythmia or Sudden Death in Patients Receiving Serotonin Reuptake Inhibitors With Methadone: A Population-Based Study

Background: Methadone is associated with ventricular dysrhythmias and sudden death. Serotonin reuptake inhibitors (SRIs) may increase the risk of these events either by inhibiting metabolism of methadone’s proarrhythmic (S)-enantiomer, additive QT interval prolongation, or both. We sought to determine whether certain SRIs were associated with a higher risk of methadone-related ventricular dysrhythmias or sudden death.

Methods: We conducted a nested case-control study of Ontario residents receiving methadone between April 1, 1996 and December 31, 2017. Cases, defined as patients who died of sudden cardiac death or were hospitalized with a ventricular dysrhythmia while on methadone, were matched with up to four controls who also received methadone on age, sex, and a disease risk score. We determined the odds ratio (OR) and p-value functions for the association between methadone-related cardiotoxicity and treatment with SRIs known to inhibit metabolism of (S)-methadone (paroxetine, fluvoxamine, sertraline) or prolong the QT interval (citalopram and escitalopram). Patients who were not treated with an SRI served as the reference group.

Results: During the study period, we identified 626 cases and 2,299 matched controls. Following multivariable adjustment, we found that recent use of sertraline, fluvoxamine or paroxetine (adjusted OR 1.30; 95% confidence intervals [CI] 0.90–1.86) and citalopram and escitalopram (adjusted OR 1.26; 95% CI 0.97–1.63) were associated with small increases in the risk methadone-related cardiac toxicity, an assertion supported by the corresponding p-value functions.

Interpretation: Certain SRIs may be associated with a small increase in cardiac toxicity in methadone-treated patients.

Dementia and in-hospital mortality: retrospective analysis of a nationwide administrative database of elderly subjects in Italy

AIMS

 To evaluate the relationship between comorbidity and in-hospital mortality in elderly patients affected by dementia.

METHODS

Data were obtained from the Italian Ministry of Health and included all discharge records from Italian hospitals concerning subjects aged ≥ 65 years admitted to acute Internal Medicine or Geriatrics wards between January 2015 and December 2016 (3.695.278 admissions). The variables analyzed included age, sex, and in-hospital death. Twenty-five homogeneous clusters of diseases were identified in discharge codes according to the ICD-9-CM classification.

RESULTS

Patients with dementia represented 7.5% of the sample (n. 278.149); they were older, more often males (51.9%), and had a higher in-hospital mortality (24.3%) compared to patients without dementia (9.7%). Dementia per se doubled the odds of death (OR 1.98; 95% CI 1.95-2.00), independent of age, sex, and comorbidities. Seven clusters of disease (pneumonia, heart failure, kidneys disease, cancer, infectious diseases, diseases of fluids/electrolytes and general symptoms) were associated with increased in-hospital mortality, independent of the presence/absence of dementia. Among patients with dementia, heart failure, pneumonia and kidney disease on their own substantially doubled/tripled mortality risk. The risk increased from 10.1% (none of selected conditions), up to 28.9% when only one of selected comorbidities was present, rising to 52.3% (OR: 9.34; p < 0.001) when two or more comorbidities were simultaneously diagnosed, besides general symptoms.

CONCLUSIONS

Our study confirmed an important increase of in-hospital mortality in older subjects with dementia. Despite a different comorbidity, the conditions associated with in-hospital mortality were substantially the same in patients with or without dementia. Heart failure, pneumonia, and kidney disease identified a high risk of in-hospital mortality among subjects with dementia.

Comparative safety of inhaled corticosteroids and macrolides in Medicare enrollees with bronchiectasis

Introduction

Bronchiectasis is an increasingly common chronic inflammatory airway disease. We evaluated secondary safety outcomes in a comparative effectiveness study of chronic inhaled corticosteroids (ICS) and macrolide monotherapy in bronchiectasis patients.

Methods

We conducted a retrospective study using US Medicare Parts A, B and D (but not C) 2006–2014 datasets. Among those with a pulmonologist-associated bronchiectasis claim (ICD-9-CM 494.0 or 494.1), without cystic fibrosis, we identified the first new use of either chronic (>28 days) ICS or macrolide monotherapy. For each drug exposure, we calculated crude incidence rates of the secondary safety outcomes: arrhythmia, myocardial infarction, sensorineural hearing loss, hip fracture and opportunistic infections. We calculated a propensity score (PS) for ICS use using demographic, clinical and utilisation characteristics and compared risks of macrolides versus ICS for each outcome using PS decile-adjusted Cox regression models.

Results

Of 285 043 Medicare patients with bronchiectasis, we identified 6500 (2%) macrolide and 83 589 (29%) ICS new users. Key covariates were balanced across exposure groups within decile. Myocardial infarction, hip fracture and opportunistic infection were not significantly associated with treatment. Macrolides were associated with a decreased risk of arrhythmia (adjusted hazard ratio (aHR) 0.87, 95% CI 0.80–0.94) and an increased risk of sensorineural hearing loss (aHR 1.38, 95% CI 1.56–1.22) compared to ICS.

Conclusions

Macrolides were not associated with an elevated risk of acute cardiac events compared to ICS. The increased risk of hearing loss in macrolide users compared to ICS users in older bronchiectasis patients should be balanced against known benefits of macrolides.

Comparison of risks of cardiac outcomes (arrhythmia and myocardial infarction), hearing loss, opportunistic infections and hip fracture between macrolide and ICS users with bronchiectasis using a robust propensity-score adjusted new-user methodologyhttps://bit.ly/3KIVp0O

Simple compared to covariate-constrained randomization methods in balancing baseline characteristics: a case study of randomly allocating 72 hemodialysis centers in a cluster trial

Background and aim

Some parallel-group cluster-randomized trials use covariate-constrained rather than simple randomization. This is done to increase the chance of balancing the groups on cluster- and patient-level baseline characteristics. This study assessed how well two covariate-constrained randomization methods balanced baseline characteristics compared with simple randomization.

Methods

We conducted a mock 3-year cluster-randomized trial, with no active intervention, that started April 1, 2014, and ended March 31, 2017. We included a total of 11,832 patients from 72 hemodialysis centers (clusters) in Ontario, Canada. We randomly allocated the 72 clusters into two groups in a 1:1 ratio on a single date using individual- and cluster-level data available until April 1, 2013. Initially, we generated 1000 allocation schemes using simple randomization. Then, as an alternative, we performed covariate-constrained randomization based on historical data from these centers. In one analysis, we restricted on a set of 11 individual-level prognostic variables; in the other, we restricted on principal components generated using 29 baseline historical variables.

We created 300,000 different allocations for the covariate-constrained randomizations, and we restricted our analysis to the 30,000 best allocations based on the smallest sum of the penalized standardized differences. We then randomly sampled 1000 schemes from the 30,000 best allocations. We summarized our results with each randomization approach as the median (25th and 75th percentile) number of balanced baseline characteristics. There were 156 baseline characteristics, and a variable was balanced when the between-group standardized difference was ≤ 10%.

Results

The three randomization techniques had at least 125 of 156 balanced baseline characteristics in 90% of sampled allocations. The median number of balanced baseline characteristics using simple randomization was 147 (142, 150). The corresponding value for covariate-constrained randomization using 11 prognostic characteristics was 149 (146, 151), while for principal components, the value was 150 (147, 151).

Conclusion

In this setting with 72 clusters, constraining the randomization using historical information achieved better balance on baseline characteristics compared with simple randomization; however, the magnitude of benefit was modest.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05590-1.

Comorbid depression in surgical cancer patients associated with non-routine discharge and readmission

OBJECTIVE

To characterize the rates of depression across primary cancer sites, and determine the effects of comorbid depression among surgical cancer patients on established quality of care indicators, non-routine discharge and readmission.

METHODS

Patients undergoing surgical resection for cancer were selected from the Nationwide Readmissions Database (2010-2014). Multivariable analysis adjusted for patient and hospital level characteristics to ascertain the effect of depression on post-operative outcomes and 30-day readmission rates. Non-routine discharge encompasses discharge to skilled nursing, inpatient rehabilitation, and intermediate care facilities, as well as discharge home with home health services.

RESULTS

Among 851,606 surgically treated cancer patients, 8.1% had a comorbid diagnosis of depression at index admission (n = 69,174). Prevalence of depression was highest among patients with cancer of the brain (10.9%), female genital organs (10.9%), and lung (10.5%), and lowest among those with prostate cancer (4.9%). Depression prevalence among women (10.9%) was almost twice that of men (5.7%). Depression was associated with non-routine discharge after surgery (OR 1.20, CI:1.18-1.23, p < 0.0001*) and hospital readmission within 30 days (OR 1.12, CI:1.09-1.15, p < 0.001*).

CONCLUSION

Rates of depression vary amongst surgically treated cancer patients by primary tumor site. Comorbid depression in these patients is associated with increased likelihood of non-routine discharge and readmission.

Short-term laboratory and related safety outcomes for the multiple sclerosis oral disease-modifying therapies: an observational study

BACKGROUND

Real-world safety data for the oral multiple sclerosis (MS) disease-modifying therapies (DMTs), dimethyl fumarate (DMF), fingolimod, and teriflunomide are important. We examined laboratory test abnormalities and adverse health conditions in new users.

METHODS

Linked laboratory and administrative health data were accessed for all persons with MS (PwMS) filling their first oral DMT prescription in two Canadian provinces. PwMS were followed from first prescription fill until discontinuation, death, emigration or study end. Proportions of PwMS, and incidence rates (IR)/100 person-years, were calculated for ≥1 event of elevated alanine aminotransferase (ALT) (>the upper limit of normal [ULN]; all DMTs), liver toxicity (ALT>3xULN; fingolimod); lymphopenia and proteinuria (DMF), and cardiac arrhythmia, hypertension and pneumonia (all DMTs).

RESULTS

Overall, 1,140 PwMS were followed for up to 2 years. De novo elevated alanine aminotransferase affected 13.2% (DMF), 12.4% (teriflunomide), and 30.0% (fingolimod) of users. Liver toxicity affected 2.8% of fingolimod, lymphopenia 3.1% of DMF, and proteinuria 2.9% of DMF users. The incidences of cardiac arrhythmia, pneumonia and hypertension ranged from <1 to 1.86/100 person-years depending on the DMT.

CONCLUSIONS

The short-term, real-world incidences of abnormal laboratory results or adverse events were consistent with the pivotal clinical trial findings. Longer-term safety data are still needed.

Increased complication and mortality among non-index hospital readmissions after brain tumor resection is associated with low-volume readmitting hospitals

OBJECTIVE

Fragmentation of care following craniotomy for tumor resection is increasingly common with the regionalization of neurosurgery. Hospital readmission to a hospital (non-index) other than the one from which patients received their original care (index) has been associated with increases in both morbidity and mortality for cancer patients. The impact of non-index readmission after surgical management of brain tumors has not previously been evaluated. The authors set out to determine rates of non-index readmission following craniotomy for tumor resection and evaluated outcomes following index and non-index readmissions.

METHODS

Retrospective analyses of data from cases involving resection of a primary brain tumor were conducted using data from the Nationwide Readmissions Database (NRD) for 2010-2014. Multivariate logistic regression was used to evaluate the independent association of patient and hospital factors with readmission to an index versus non-index hospital. Further analysis evaluated association of non-index versus index hospital readmission with mortality and major complications during readmission. Effects of readmission hospital procedure volume on mortality and morbidity were evaluated in post hoc analysis.

RESULTS

In a total of 17,459 unplanned readmissions, 84.4% patients were readmitted to index hospitals and 15.6% to non-index hospitals. Patient factors associated with increased likelihood of non-index readmission included older age (75+: OR 1.44, 95% CI 1.19-1.75), elective index admission (OR 1.19, 95% CI 1.08-1.30), increased Elixhauser comorbidity score ≥2 (OR 1.18, 95% CI 1.01-1.37), and malignant tumor diagnosis (OR 1.32, 95% CI 1.19-1.45) (all p < 0.04). Readmission to a non-index facility was associated with a 28% increase in major complications (OR 1.28, 95% CI 1.14-1.43, p < 0.001) and 21% increase in mortality (OR 1.21, 95% CI 1.02-1.44, p = 0.032) in initial analysis. Following a second multivariable logistic regression analysis including the readmitting hospital characteristics, low procedure volume of a readmitting facility was significantly associated with non-index readmission (p < 0.001). Readmission to a lower-procedure-volume facility was associated with a 46%-75% increase in mortality (OR 1.46-1.75, p < 0.005) and a 21%-35% increase in major complications (OR 1.21-1.34, p < 0.005). Following adjustment for volume at a readmitting facility, admission to a non-index facility was no longer associated with mortality (OR 0.90, 95% CI 0.71-1.14, p = 0.378) or major complications (OR 1.09, CI 0.94-1.26, p = 0.248).

CONCLUSIONS

Of patient readmissions following brain tumor resection, 15.6% occur at a non-index facility. Low procedure volume is a confounder for non-index analysis and is associated with an increased likelihood of major complications and mortality, as compared to readmission to high-procedure-volume hospitals. Further studies should evaluate interventions targeting factors associated with unplanned readmission.

Maternal, pregnancy, and neonatal outcomes for women with Marfan syndrome

BACKGROUND

Marfan syndrome (MFS) is an autosomal dominant hereditary disorder which affects cardiovascular structure and function. With medical advances, more women with MFS experience pregnancy, which may increase maternal and neonatal risk. Existing research has been limited by small or clinical samples. This study examines the association of MFS and adverse maternal, neonatal, and obstetric outcomes.

METHODS

We conducted a cross-sectional study using the discharge abstract database, containing all labor and delivery hospitalizations in Canada (excluding Quebec) from fiscal years 2004-2015 where women delivered a live- or stillbirth. We measured maternal and neonatal morbidity, preterm births (<37 weeks), small-for-gestational-age births, perinatal mortality, and adverse maternal cardiovascular events. For each outcome, we calculated the absolute risk for women with and without MFS and used generalized estimating equations with a logit function to calculate odds.

RESULTS

Overall, 2,682,461 women delivered a live or stillborn infant in Canada during the study period, with 135 birth events to women with MFS. Women with MFS did not have significantly higher odds of severe maternal morbidity during their delivery (aOR:1.3; 95%CI: 0.4-4.0). Similarly, their infants did not have significantly higher odds of neonatal morbidity. However, infants born to women with MFS were significantly more likely to be born preterm (aOR:2.6; 95%CI: 1.6-4.3) and to be small-for-gestational-age (aOR:1.8; 95%CI:1.0-3.1).

CONCLUSIONS

This population-based study indicates that, although some women with MFS may experience higher odds of maternal and/or neonatal morbidity during labor and delivery, the majority of women with MFS can have healthy births with proper clinical management.

Risk of cardiac events with azithromycin-A prediction model

Previous studies have suggested an increased risk of cardiac events with azithromycin, but the predictors of such events are unknown. We sought to develop and validate two prediction models to identify such predictors. We used data from Truven Marketscan Database (01/2009 to 06/2015). Using a split-sample approach, we developed two prediction models, which included baseline demographics, clinical conditions (Model 1), concurrent use of any drug (Model 1) and therapeutic class (Model 2) with a risk of QT-prolongation (CQT-Rx). Patients enrolled in a health plan for 365 days before and five days after dispensing of azithromycin (episodes). Cardiac events included syncope, palpitations, ventricular arrhythmias, cardiac arrest as a primary diagnosis for hospitalization including death. For each model, a backward elimination of predictors using logistic regression was applied to identify predictors in 100 random samples of the training cohort. Predictors prevalent in >50% of the models were included in the final model. A score for the Assessment of Cardiac Risk with Azithromycin (ACRA) was generated using the training cohort then tested in the validation cohort. A cohort of 20,134,659 episodes with 0.03% cardiac events were included. Over 60% included females with mean age of 40.1±21.3 years. Age, sex, history of syncope, cardiac dysrhythmias, non-specific chest pain, and presence of a CQT-Rx were included as predictors for Model-1 (c-statistic = 0.68). For Model-2 (c-statistic = 0.64), predictors included age, sex, anti-arrhythmic agents, anti-emetics, antidepressants, loop diuretics, and ACE inhibitors. ACRA score is available online (bit.ly/ACRA_2020). The ACRA score may help identify patients who are at higher risk of cardiac events following treatment with azithromycin. Providers should assess the risk-benefit of using azithromycin and consider alternative antibiotics among high-risk patients.

Readmission with venous thromboembolism after surgical treatment by primary cancer site

BACKGROUND

Venous thromboembolism (VTE) is a common, high-mortality condition among surgical cancer patients. Comprehensive analyses of VTE among postoperative cancer patients are lacking. We sought to determine the association between readmission with VTE and primary cancer diagnosis in a nationwide database at 90- and 180-days after initial admission for cancer surgery.

METHODS

Retrospective analyses of post-surgical cancer patients readmitted with VTE were conducted using data from the Nationwide Readmissions Database (NRD) (2010-2014). Multivariate logistic regression models adjusting for patient and hospital factors were used to determine 90- and 180-day readmission rates for VTE by cancer type. Patient factors associated with readmission were also examined.

RESULTS

Among a sample of 535,992 cancer patients undergoing tumor resection, readmission with VTE occurred in 1.7% within 90-days and 2.3% within 180-days. Patients readmitted for VTE experienced a 7% mortality rate. Highest rates of VTE readmission at 180 days occurred in brain (6.7%), pancreatic (5.6%), and respiratory and intrathoracic cancers (4.4%). Using pancreatic cancer as reference, brain cancer had the highest odds of readmission at 180-days (OR 2.23, 95% CI [1.95-2.55]).

CONCLUSION

Readmission with VTE among surgical cancer patients occurred in 2.3% of patients within 180 days. Among cancer types, primary brain cancer was independently associated with readmission with VTE.

Comparison of Cardiac Events Associated With Azithromycin vs Amoxicillin

IMPORTANCE

Conflicting evidence exists on the association between azithromycin use and cardiac events.

OBJECTIVE

To compare the odds of cardiac events among new users of azithromycin relative to new users of amoxicillin using real-world data.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study used data from Truven Health Analytics MarketScan database from January 1, 2009, to June 30, 2015. Patients receiving either amoxicillin or azithromycin and enrolled in a health care plan 365 days before (baseline period) the dispensing date (index date) were included in the study. Patients were matched 1:1 on high-dimensional propensity scores. Data were analyzed from October 1, 2018, to December 31, 2019.

EXPOSURES

New use of azithromycin compared with new use of amoxicillin.

MAIN OUTCOMES AND MEASURES

The primary outcome consisted of cardiac events, including syncope, palpitations, ventricular arrhythmias, cardiac arrest, or death as a primary diagnosis for hospitalization at 5, 10, and 30 days from the index date. Logistic regression models were used to estimate odds ratios (ORs) with 95% CIs.

RESULTS

After matching, the final cohort included 2 141 285 episodes of each index therapy (N = 4 282 570) (mean [SD] age of patients, 35.7 [22.3] years; 52.6% female). Within 5 days after therapy initiation, 1474 cardiac events (0.03%) occurred (708 in the amoxicillin cohort and 766 in the azithromycin cohort). The 2 most frequent events were syncope (1032 [70.0%]) and palpitations (331 [22.5%]). The odds of cardiac events with azithromycin compared with amoxicillin were not significantly higher at 5 days (OR, 1.08; 95% CI, 0.98-1.20), 10 days (OR, 1.05; 95% CI, 0.97-1.15), and 30 days (OR, 0.98; 95% CI, 0.92-1.04). Among patients receiving any concurrent QT-prolonging drug, the odds of cardiac events with azithromycin were 1.40 (95% CI, 1.04-1.87) greater compared with amoxicillin. Among patients 65 years or older and those with a history of cardiovascular disease and other risk factors, no increased risk of cardiac events with azithromycin was noted.

CONCLUSIONS AND RELEVANCE

This study found no association of cardiac events with azithromycin compared with amoxicillin except among patients using other QT-prolonging drugs concurrently. Although azithromycin is a safe therapy, clinicians should carefully consider its use among patients concurrently using other QT-prolonging drugs.

Patients With a History of a Cardiac Implantable Electronic Device Have a Higher Likelihood of 90-Day Cardiac Events After Total Joint Arthroplasty: A Matched Cohort Study

INTRODUCTION

We sought to identify the incidence of new 90-day cardiac events, 90-day mortality, 90-day unplanned readmissions, and 30-day emergency department (ED) visits after total joint arthroplasty (TJA) in patients with a history of a cardiac implantable electronic device (CIED) and compare these outcomes in TJA patients without a CIED.

METHODS

Kaiser Permanente's Cardiac Device and Total Joint Replacement Registries were used to identify elective primary TJA performed for osteoarthritis. TJA with a CIED was matched with TJA without a CIED (n = 365 pairs) on patient characteristics, demographics, and procedure type. A McNemar test was used to evaluate categorical outcomes.

RESULTS

Of the TJA with a CIED, there were 24 cardiac events (6.6%), 1 mortality (0.3%), 30 readmissions (8.2%), and 39 ED visits (10.7%). TJA patients with a CIED had a higher likelihood of cardiac events (odds ratio [OR] = 3.14, 95% confidence interval [CI] = 1.28 to 8.08). No difference was observed in mortality (OR = 0.50, 95% CI = 0.02 to 6.98), readmissions (OR = 1.26, 95% CI = 0.71 to 2.25), or ED visits (OR = 1.15, 95% CI = 0.71 to 1.88).

CONCLUSION

In our matched cohort study, TJA patients with a history of a CIED had a higher likelihood of incident 90-day cardiac events when compared with patients without a CIED without a difference observed for 90-day mortality, unplanned readmission, and 30-day ED visit.

LEVEL OF EVIDENCE

Level III.

Maternal, pregnancy, and neonatal outcomes for women with Turner syndrome

BACKGROUND

Turner syndrome (TS) occurs in approximately 1 in 2500 live female births and is caused by the partial or complete loss of one of the X chromosomes, resulting in abnormalities such as ovarian failure and infertility. However, pregnancy in women with TS may still occur via spontaneous pregnancy or through oocyte donation. Limited data exists on pregnancy in women with TS that could aid in clinical care.

METHODS

We conducted a population-based cross-sectional study using data from the Discharge Abstract Database (2004-2015), which contains all labor and delivery hospitalizations across Canada (excluding Quebec) where women delivered a live or stillborn infant. The odds of adverse maternal and neonatal outcomes for women with and without TS were calculated using backwards multivariable logistic regression with generalized estimating equations, adjusting for the Obstetric Comorbidity Index, mode of delivery, and year.

RESULTS

Overall, 2,682,284 women delivered a live or stillborn infant during the study period and 44 birth events occurred for women with TS. No severe maternal morbidity or adverse cardiovascular events occurred for women with TS at their labor and delivery hospitalization. However, infants born to women with TS were 3.6 times more likely (95% CI: 1.7-7.8) to experience neonatal morbidity than those born to women without TS. These infants also were more likely to have had a preterm birth (aOR: 2.9, 95% CI: 1.6-5.4) and to be small-for-gestational-age (aOR: 4.5, 95% CI: 2.4-8.4).

CONCLUSION

This study adds further understanding of the likelihood of adverse outcomes for pregnant women with TS.

Validity of administrative claims-based algorithms for ventricular arrhythmia and cardiac arrest in the pediatric population

PURPOSE

Identify administrative claims-based algorithms for capturing out-of-hospital ventricular arrhythmias (VA) and cardiac arrests (CA) due to cardiac causes in the pediatric population with high positive-predictive value (PPV).

METHODS

Within a single pediatric center, a retrospective cohort of patients hospitalized or seen in the emergency room for VA or CA were identified from the electronic health records. Eligible encounters were blindly reviewed and linked to administrative data, including ICD-9/ICD-10 codes. Test characteristics, including PPV, for different diagnostic and procedure codes were generated using a 50% training sample. The gold standard was definite or suspected out-of-hospital VA or CA due to cardiac cause verified based on clinical criteria. Algorithms with the highest PPV were then applied to a 50% validation sample to validate performance.

RESULTS

From 2004-2017, 598 encounters met eligibility criteria. 174 (29%) had an outcome of interest, with remainder being an inpatient event or CA due to other cause. Within the training sample (n = 263), VA codes in primary position had a PPV 94% (95%CI 81%-99%) with low sensitivity (44%, 95%CI 33%-56%). CA codes in any position or VA codes in nonprimary positions had low PPV (18%-19%, 31% respectively). Applying the top three performing algorithms to the validation sample (n = 252) yielded similar PPV values.

CONCLUSIONS

Contrary to adults, algorithms including a CA code do not perform well for identifying out-of-hospital VA and CA due to cardiac cause in the pediatric populations. Researchers should be aware of the potential implications for future pediatric drug safety studies for these outcomes.

Risk of Serious Ventricular Arrhythmia in Users of Gastrointestinal Medications: A Retrospective Cohort Study in China

INTRODUCTION

Clinical data have demonstrated prolongation of the QTc interval associated with domperidone use. The risk of serious ventricular arrhythmias (SVA) in clinical practice in China has not been investigated.

METHODS

The incidence of SVA and all-cause cardiac arrest associated with medications for gastrointestinal disorders in China was assessed in a retrospective cohort study using information from electronic medical record databases from the Xijing and Guangzhou general hospitals. Inpatients and outpatients with at least one prescription for domperidone, mosapride/itopride, metoclopramide, a proton pump inhibitor (PPI), or histamine H₂ receptor antagonist were identified in the hospital databases from January 1, 2009 to December 31, 2014.

RESULTS

The inpatient exposure cohorts included 66,282 inpatients at Xijing and 23,643 inpatients at Guangzhou hospitals. There were 67 cases of SVA and two cases of SVA at the respective hospitals during the study period. Three cases (all at Xijing) occurred in patients prescribed domperidone (incidence rate 2.9/100 person-years (PYs), 95% CI 0.9-9.0) compared to 1.3/100 PYs (95% CI 0.2-8.9) for mosapride/itopride and 5.6/100 PYs (95% CI 4.4-7.2) for PPIs. The hazard ratio adjusted for age, sex, and co-morbidities for SVA in patients prescribed domperidone compared to PPIs was 0.79 (95% CI 0.25-2.56). There were 44 cases of all-cause cardiac arrest at Xijing and 21 at Guangzhou hospital. Three patients had received domperidone and all had underlying cardiovascular diseases.

CONCLUSIONS

SVA and cardiac arrest are very rare events in patients prescribed medications for gastrointestinal disorders in China. We found no evidence that domperidone carried a higher risk of SVA compared to other gastrointestinal medications.

Characterizing Health Outcomes in Idiopathic Pulmonary Fibrosis using US Health Claims Data

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a life-threatening interstitial lung disease (ILD). Characterizing health outcomes of IPF patients is challenging due to disease rarity.

OBJECTIVE

This study aimed to identify the burden of disease in patients newly diagnosed with IPF.

METHODS

Patients with ≥1 claim with an IPF diagnosis were identified from a United States healthcare insurer's database (2000-2013). Patients with other known causes of ILD or aged <40 years were excluded. Subgroups were compared based on the 2011 change in International Classification of Diseases, 9th Revision (ICD-9) definition of IPF and occurrence of IPF testing. The prevalence and incidence of preselected health conditions of clinical interest were estimated.

RESULTS

Median age of newly diagnosed patients (n = 7,298) was 62 years (54.0% male). Restricting to patients with IPF diagnostic testing did not substantially affect cohort characteristics, nor did ICD-9 IPF coding change. Mean follow-up was 1.7 years; 16.8% of patients died; and a substantial proportion of patients were censored due to end of health plan enrollment (50.7%) and other causes of ILD (19.6%). The incidence of pulmonary hypertension, lung cancer, and claims-based algorithm proxy for acute respiratory worsening of unknown cause was 22.5, 17.6, and 12.6 per 1,000 person-years, respectively.

CONCLUSIONS

Patients with IPF had a high disease burden with a variety of health outcomes observed, including a high rate of mortality. Database censoring due to changes in enrollment or other ILD diagnoses limited follow-up. Altering cohort entry definitions, including IPF testing or ICD-9 IPF coding change, had little impact on cohort baseline characteristics.

Diagnostic Algorithms for Cardiovascular Death in Administrative Claims Databases: A Systematic Review

INTRODUCTION

Valid algorithms for identification of cardiovascular (CV) deaths allow researchers to reliably assess the CV safety of medications, which is of importance to regulatory science, patient safety, and public health.

OBJECTIVE

The aim was to conduct a systematic review of algorithms to identify CV death in administrative health plan claims databases.

METHODS

We searched MEDLINE, EMBASE, and Cochrane Library for English-language studies published between January 1, 2012 and October 17, 2017. We examined references in systematic reviews to identify earlier studies. Selection included any observational study using electronic health care data to evaluate the sensitivity, specificity, positive predictive value (PPV), or negative predictive value (NPV) of algorithms for CV death (sudden cardiac death [SCD], myocardial infarction [MI]-related death, or stroke-related death) among adults aged ≥ 18 years in the United States. Data were extracted by two independent reviewers, with disagreements resolved through further discussion and consensus. The Quality Assessment of Diagnostic Accuracy Studies-2 instrument was used to assess the risk of bias.

RESULTS

Five studies (n = 4 on SCD, n = 1 on MI- and stroke-related death) were included after a review of 2053 citations. All studies reported algorithm PPVs, with incomplete reporting on other accuracy parameters. One study was at low risk of bias, three studies were at moderate risk of bias, and one study was at unclear risk of bias. Two studies identified community-occurring SCD: one identified events using International Classification of Disease, Ninth Revision (ICD-9) codes on death certificates and other criteria from medical claims (PPV = 86.8%) and the other identified events resulting in hospital presentation using first-listed ICD-9 codes on emergency department or inpatient medical claims (PPV = 92.3%). Two studies used death certificates alone to identify SCD (PPV = 27% and 32%, respectively). One study used medical claims to identify CV death (PPV = 36.4%), coronary heart disease mortality (PPV = 28.3%), and stroke mortality (PPV = 34.5%).

CONCLUSION

Two existing algorithms based on medical claims diagnoses with or without death certificates can accurately identify SCD to support pharmacoepidemiologic studies. Developing valid algorithms identifying MI- and stroke-related death should be a research priority. PROSPERO 2017 CRD42017078745.

Capturing anaphylaxis through medical records: Are ICD and CPT codes sufficient?

OBJECTIVE

The identification of anaphylaxis cases is imperative for optimal clinicalprovider knowledge deficiencies in diagnosis and treatment and the efficacy of reimbursement codes, such as International Classification of Diseases (ICD) and current procedural terminology (CPT) codes, in detecting anaphylaxis.

DATA SOURCES

Pubmed.

STUDY SELECTIONS

Recent and clinically relevant literature on anaphylaxis and provider knowledge, ICD, CPT, Healthcare Common Procedural Coding System (HCPCS), and E-codes were selected and reviewed.

RESULTS

Reimbursement codes are used to detect anaphylaxis in administrative claims databases. Inaccurate recognition of the diagnosis by providers, underreporting, and cause identification are challenges faced by health researchers using reimbursement codes for anaphylaxis case identification. Anaphylactic shock-specific ICD codes were noted to have a positive predictive value (PPV) of 52% to 53% of anaphylaxis events compared with physician chart review, which was improved to 63% to 67.3% when used in conjunction with anaphylaxis symptom-specific ICD, CPT, HCPCS, and E-codes 31, 34, and 35.

CONCLUSION

Education of providers to properly diagnose and treat anaphylaxis requires systematic and educational investments. The ICD codes specific to anaphylactic shock have suboptimal PPV to identify anaphylaxis in administrative claims databases. Use of algorithms incorporating other reimbursement codes improve the PPV, but they are limited by inaccurate diagnoses and underreporting of anaphylaxis. Future ICD-11 reclassification may improve anaphylaxis detection by reimbursement codes.

Contemporary impacts of a cancer diagnosis on survival following in-hospital cardiac arrest

AIM

The objective of this study was to determine whether survival and post-arrest procedural utilization following in-hospital cardiac arrest (IHCA) differ in patients with and without comorbid cancer.

METHODS

We retrospectively reviewed all adult (age ≥18 years old) hospital admissions complicated by IHCA from 2003 to 2014 using the National Inpatient Sample (NIS) dataset. Utilizing propensity score matching using age, gender, race, insurance, all hospital level variables, HCUP mortality score, diabetes, hypertension and cardiopulmonary resuscitation use, rates of survival to hospital discharge and post-arrest procedural utilization were compared.

RESULTS

From 2003 to 2014, there were a total of 1,893,768 hospitalizations complicated by IHCA, of which 112,926 occurred in patients with history of cancer. In a propensity matched cohort from 2012 to 2014, those with cancer were less likely to survive the hospitalization (31% vs. 46%, p < 0.0001). Following an IHCA, rates of procedural utilization in patients with cancer were significantly less when compared to those without a concurrent malignancy: coronary angiography (4.0% vs. 13.0%), percutaneous coronary intervention (2.2% and 8.0%), targeted temperature management (0.8% vs. 6.0%); p < 0.0001 for all comparisons. This patient population was less likely to have acute coronary syndrome (12.6% vs. 27.0%) or congestive heart failure (24.5% vs. 38.2%); p < 0.0001 for both comparisons. Survival improved in both groups over the study period (p < 0.0001).

CONCLUSIONS

Patients with a history of cancer who sustain IHCA are less likely to receive post-arrest procedures and survive to hospital discharge. Given the expected rise in the rates of cancer survivorship, these findings highlight the need for broader application of potentially life-saving interventions to lower risk cancer patients who have sustained a cardiac arrest.

Challenges and Opportunities for Using Big Health Care Data to Advance Medical Science and Public Health

Methodological advancements in epidemiology, biostatistics, and data science have strengthened the research world's ability to use data captured from electronic health records (EHRs) to address pressing medical questions, but gaps remain. We describe methods investments that are needed to curate EHR data toward research quality and to integrate complementary data sources when EHR data alone are insufficient for research goals. We highlight new methods and directions for improving the integrity of medical evidence generated from pragmatic trials, observational studies, and predictive modeling. We also discuss needed methods contributions to further ease data sharing across multisite EHR data networks. Throughout, we identify opportunities for training and for bolstering collaboration among subject matter experts, methodologists, practicing clinicians, and health system leaders to help ensure that methods problems are identified and resulting advances are translated into mainstream research practice more quickly.

Is obstructive sleep apnea associated with ventricular tachycardia? A retrospective study from the National Inpatient Sample and a literature review on the pathogenesis of Obstructive Sleep Apnea

BACKGROUND

Obstructive sleep apnea (OSA) is a known independent risk factor for a multiple cardiovascular morbidities and mortality. The association of OSA and ventricular arrhythmias is less well understood. The aim of this analysis is to study the relationship between OSA and ventricular tachyarrhythmias.

HYPOTHESIS

OSA is associated with increased ventricular arrhythmias.

METHODS

Data from the national inpatient sample (NIS) 2012 to 2014, were reviewed. Discharges associated with OSA were identified as the target population using the relevant ICD-9-CM codes. The primary outcome was a diagnosis of ventricular tachycardia (VT) in the OSA population. Secondary outcomes include the rate of ventricular fibrillation (VF) and cardiac arrest. Multivariable analyses were performed to examine the association of VT with multiple potential confounding clinical variables.

RESULTS

Of 18 013 878 health encounters, 943 978 subjects (5.24%) had a diagnosis of OSA. VT and VF were more prevalent among patients with OSA compared to those without a diagnosis of OSA (2.24% vs 1.16%; P < 0.001 and 0.3% vs 0.2%; P < 0.001, respectively). Odds ratio for cardiac arrest in OSA group was not statistically significant (1, 95% confidence interval 0.97-1.02, P < 0.76). In unadjusted analyses, all examined comorbidities were significantly more common in those with OSA, including diabetes mellitus, hypertension, chronic kidney disease, acute coronary syndrome, and heart failure.

CONCLUSION

OSA is associated with increased rates of ventricular tachyarrhythmia.

Association of oral ciprofloxacin, levofloxacin, ofloxacin and moxifloxacin with the risk of serious ventricular arrhythmia: a nationwide cohort study in Korea

OBJECTIVE

To evaluate whether oral ciprofloxacin, levofloxacin, ofloxacin and moxifloxacin increase the risk of ventricular arrhythmia in Korea's general population.

DESIGN

Population-based cohort study using administrative claims data on a national scale in Korea.

SETTING

All primary, secondary and tertiary care settings from 1 January 2015 to 31 December 2015.

PARTICIPANTS

Patients who were prescribed the relevant study medications at outpatient visits.

PRIMARY OUTCOME MEASURES

Each patient group that was prescribed ciprofloxacin, levofloxacin, ofloxacin or moxifloxacin was compared with the group that was prescribed cefixime to assess the risk of serious ventricular arrhythmia (ventricular tachycardia, fibrillation, flutter and cardiac arrest). Using logistic regression analysis with inverse probability of treatment weighting using the propensity score, OR and 95% CI for serious ventricular arrhythmia were calculated for days 1-7 and 8-14 after the patients commenced antibiotic use.

RESULTS

During the study period, 4 888 890 patients were prescribed the study medications. They included 1 466 133 ciprofloxacin users, 1 141 961 levofloxacin users, 1 830 786 ofloxacin users, 47 080 moxifloxacin users and 402 930 cefixime users. Between 1 and 7 days after index date, there was no evidence of increased serious ventricular arrhythmia related to the prescription of ciprofloxacin (OR 0.72; 95% CI 0.49 to 1.06) and levofloxacin (OR 0.92; 95% CI 0.66 to 1.29). Ofloxacin had a 59% reduced risk of serious ventricular arrhythmia compared with cefixime during 1-7 days after prescription. Whereas the OR of serious ventricular arrhythmia after the prescription of moxifloxacin was 1.87 (95% CI 1.15 to 3.11) compared with cefixime during 1-7 days after prescription.

CONCLUSIONS

During 1-7 days after prescription, ciprofloxacin and levofloxacin were not associated with increased risk and ofloxacin showed reduced risk of serious ventricular arrhythmia. Moxifloxacin increased the risk of serious ventricular arrhythmia.

Cardiac sarcoidosis and ventricular arrhythmias. A rare association of a rare disease. A retrospective cohort study from the National Inpatient Sample and current evidence for management

BACKGROUND

Sarcoidosis is an increasingly recognized multi-systemic condition. Cardiac sarcoidosis is associated with ventricular arrhythmias and higher mortality rates. Little epidemiological data is available regarding the disease and associated ventricular arrhythmias.

METHODS

Data from the National Inpatient Sample (NIS) database 2012-2014, were reviewed. Dis-charges associated with sarcoidosis were identified as the target population using relevant ICD-9-CM codes. Primary outcome was a diagnosis of ventricular tachycardia (VT) in the sarcoidosis population. Secondary outcomes include rate of ventricular fibrillation (VF) and cardiac arrest. Subgroup analyses were performed to examine the association of VT with multiple potential confounding clinical variables.

RESULTS

Of 18,013,878 health encounters, 46,289 (0.26%) subjects had a diagnosis of sarcoidosis. VT and VF were more prevalent among patients with sarcoidosis compared to those without a diagnosis of sarcoidosis (2.29% vs. 1.22%; p < 0.001 and 0.25% vs. 0.21%; p < 0.001, respectively). Sarcoidosis was also associated with a higher prevalence of cardiac arrest (0.72% vs. 0.6%; p < 0.001). In unadjusted analyses, all examined comorbidities were significantly more common in those with sar-coidosis, including diabetes mellitus (31.6% vs. 21.25%; p < 0.001), hypertension (65.2% vs. 51.74%; p < 0.001), chronic kidney disease (21.09% vs. 14.02%; p < 0.001), heart failure (24.87% vs. 15%; p < 0.001) and acute coronary syndrome (4.32% vs. 3.35%; p < 0.001).

CONCLUSIONS

The present study showed that sarcoidosis was associated with increased rates of ven-tricular tachyarrhythmia, which can affect the overall disease morbidity and mortality.

Cardiovascular Events Following Treatment Initiation with Atypical Antipsychotic Medications in Publicly Insured U.S. Youth

OBJECTIVE

To assess the risk of incident cardiovascular events that led to hospitalizations or emergency department visits following atypical antipsychotic (AAP) treatment initiation in youth according to dose, duration of use, and concomitant use of leading psychotropic medication classes.

METHODS

We used computerized Medicaid claims to conduct a retrospective cohort study of youth (5-20 years) who initiated AAP treatment. AAP use was operationalized in a time-dependent manner according to current vs. former use, average daily dose (in risperidone dose equivalents), and duration of use. In a secondary analysis, concomitant use of (1) stimulants and (2) serotonin-reuptake inhibitors (SSRI/SNRIs) with AAPs was also assessed. To account for confounding, disease risk score methodology was used in discrete time failure models.

RESULTS

There were 74,700 youth who initiated AAP treatment (average follow-up = 24.8 months). During follow-up, the risk of cardiovascular events was significantly greater during current than former AAP use (RR = 1.55, 95% CI = 1.09-2.21). Furthermore, for current users of AAPs, the risk of cardiovascular events intensified with average daily dose (RR = 2.04, 95% CI = 1.11-3.77 for >3.75 mg/day vs. ≤1.25 mg/day). The risk of cardiovascular events did not significantly differ according to duration of AAP use. In AAP-treated youth, concomitant SSRI/SNRI use was associated with an increased risk of cardiovascular events (RR = 1.61, 95% CI = 1.01-2.57). By contrast, stimulant use concomitant with AAPs was not significantly associated with an increased risk of cardiovascular events.

CONCLUSIONS

In publicly insured U.S. youth, current AAP use was associated with an increased risk of incident cardiovascular events, which intensified with increasing dose and with concomitant SSRI/SNRI use. Prudent interpretation of these findings suggests that further research is needed to identify youth subpopulations with the greatest risk of developing AAP treatment-emergent cardiovascular events.

The effect of contralateral prophylactic mastectomy on breast-related charges: A 5-year analysis

BACKGROUND AND OBJECTIVES

The purpose of this study was to determine charges following unilateral mastectomy (UM) and bilateral mastectomy (BM) for patients with unilateral breast cancer (UBC). We hypothesized that BM may be associated with fewer charges over time.

METHODS

A retrospective review was conducted of patients with UBC treated between 2006 and 2010 with UM and BM in a large healthcare system. Institutional billing data were investigated for 5 years postoperatively to calculate the immediate and subsequent charges of all inpatient and outpatient breast-related care associated with the initial diagnosis for a subset of patients identified using propensity score matching method.

RESULTS

A subset of matched patients (n = 320) undergoing UM (n = 160) or BM (n = 160) were included in this analysis. At 1 year, there was a trend toward lower total charges following UM as compared with BM (median, $125 230 vs $138 467; P = .6075). However, during years 2 to 5, total charges were significantly higher following UM vs BM ($22 128 vs $13 478; P = .0116).

CONCLUSIONS

While initially higher, overall charges for BM are lower than UM between 2 and 5 years out from surgery. Further study is necessary to determine if this trend is sustained over the long term. These data can inform patient decision making regarding mastectomy for their breast cancer.

Electronic health record (EHR) based postmarketing surveillance of adverse events associated with pediatric off-label medication use: A case study of short-acting beta-2 agonists and arrhythmias

PURPOSE

Use electronic health record (EHR) data to (1) estimate the risk of arrhythmia associated with inhaled short-acting beta-2 agonists (SABA) in pediatric patients and (2) determine whether risk varied by on-label versus off-label prescribing.

METHODS

Retrospective cohort study of 335 041 children ≤18 years using EHR primary care data from 2 pediatric health systems (2011-2013). A series of monthly pseudotrials were created, using propensity score methodology to balance baseline characteristics between SABA-exposed (identified by prescription) and SABA-unexposed children. Association between SABA and subsequent arrhythmia for each health system was estimated through pooled logistic regression with separate estimates for children initiating under and over 4 years old (off-label and on-label, respectively).

RESULTS

Eleven percent of the cohort received a SABA prescription, 57% occurred under the age of 4 years (off-label). During the follow-up period, there were 283 first arrhythmia events, most commonly atrial tachyarrhythmias and premature ventricular/atrial contractions. In 1 health system, adjusted risk for arrhythmia was increased among exposed children (OR 1.89, 95% CI 1.31-2.73) without evidence of interaction between label status and risk. The absolute adjusted rate difference was 3.6/10 000 person-years of SABA exposure. The association between SABA exposure and arrhythmias was less strong in the second system (OR 1.26, 95% CI 0.30-5.33).

CONCLUSION

Using EHR data, we could estimate the risk of a rare event associated with medication use and determine difference in risk related to on-label versus off-label status. These findings support the value of EHR-based data for postmarketing drug studies in the pediatric population.

Palliative care utilization following out-of-hospital cardiac arrest in the United States

AIMS

Palliative care (PC) has become an integral component of comprehensive care provided to critically ill patients. Little is known about the utilization of palliative care following Out-of-Hospital Cardiac Arrest (OHCA) in the United States.

METHODS

We used the 2002-2013 National Inpatient Sample database to identify adults ≥18 years old with an ICD-9-CM principal diagnosis code of cardio-respiratory arrest or ventricular fibrillation (VF). Patients were categorized into two groups based on the presence of PC, then compared using Pearson χ² test for categorical variables and linear regression for continuous variables. Multiple linear and logistic regression models were conducted to identify factors associated with PC, and temporal trends in PC utilization.

RESULTS

Of the 154,177 patients hospitalized with OHCA in the U.S, 11,260 (7.3%) had PC consultations during hospitalization. PC Utilization increased from 1.5% in 2002 to 16.7% in 2013 (P-trend < 0.001). Patients who received Palliative care were older (mean age 70.7 ± 0.3 vs 65.9 ± 0.1), more likely to be female (45.8% vs 40.5%), and had higher Charlson comorbidity index ≥2 (55.8% vs 46.8%). In adjusted analyses, older age, female gender, Caucasian race, higher Charlson comorbidity index, multiorgan failure, metastatic cancer, non-shockable rhythm, admission to larger, urban and teaching hospitals were all associated with higher PC utilization.

CONCLUSION

We observed significant increase in the utilization of palliative care consultations following OHCA over the study period. This was influenced by multiple patient and hospital factors. Further investigations are needed to identify the appropriate cost-effective use of palliative care following cardiac arrest.

Algorithms used to identify ventricular arrhythmias and sudden cardiac death in retrospective studies: a systematic literature review

Drug-induced QT interval prolongation may increase the risk of sudden cardiac death or ventricular arrhythmias (SCD/VA), and therefore affects the safety profile of medications. Administrative databases can be used to inform pharmacoepidemiologic drug safety studies for such rare events. In order to compare event rates between studies, validated operational definitions of these events are needed. We conducted a systematic literature review in PubMed to identify algorithms for SCD/VA. Twenty-two studies were included in the review. Fifteen (68%) studies evaluated International Classification of Diseases, 9th revision (ICD-9) based medical data, of which six utilized a common, validated operational definition. This algorithm was based on principal hospitalization discharge diagnosis or first-listed emergency department visit diagnosis, with an average positive predictive value (PPV) of 85%. Four studies evaluated ICD-9 based death data, of which three utilized a common algorithm with an average PPV of 88%. Further validation of ICD, 10th revision algorithms are needed. In conclusion, we identified a validated algorithm for SCD/VA in medical data, as well as in death data. As such, to ensure comparability between new research and the existing literature, pharmacoepidemiologic research in this area should utilize common, validated algorithms, such as the ones identified in our review, to operationally define these events.

Antidepressants and the risk of arrhythmia in elderly affected by a previous cardiovascular disease: a real-life investigation from Italy

PURPOSE

The study aimed to fill existing knowledge gaps on the safety of antidepressant drugs (ADs) by estimating the risk of hospitalization for arrhythmia associated with use of selective serotonin reuptake inhibitors (SSRIs) and newer atypical ADs (NAAs) among elderly with previous cardiovascular (CV) events.

METHODS

The cohort was composed by 199,569 individuals aged ≥ 65 years from five Italian healthcare territorial units who were discharged for cardiovascular outcomes in the years 2008-2010. The 17,277 patients who experienced hospital admission for arrhythmia during follow-up were included as cases. Odds of current ADs use among cases (i.e., 14 days before hospital admission) was compared with (i) odds of current use of 1:5 matched controls (between-patients case-control) and with (ii) odds of previous use during 1:5 matched control periods (within-patient case-crossover). The risk of arrhythmia associated with ADs current use was modelled fitting a conditional logistic regression. A set of sensitivity analyses was performed to account for sources of systematic uncertainty.

RESULTS

Current users of SSRIs and NAAs were at increased risk of arrhythmia with case-control odds ratios (OR) of 1.37 (95% confidence interval, CI 1.18 to 1.58) and 1.41 (1.16 to 1.71) and case-crossover OR of 1.48 (1.20 to 1.81) and 1.72 (1.31 to 2.27). An increased risk of arrhythmia was associated with current use of trazodone (NAA) consistently in case-control and case-crossover designs.

CONCLUSIONS

Evidence that current use of SSRIs and NAAs is associated to an increased risk of arrhythmia among elderly with CV disease was consistently supplied by two observational approaches.

Regional Variation in Outcomes of Hospitalized Patients Having Out-of-Hospital Cardiac Arrest

The aim of this study was to investigate patient outcomes after hospitalization for out-of-hospital cardiac arrest in the United States. We used the 2002 to 2013 Nationwide Inpatient Sample database to identify adults ≥18 years with an International Classification of Diseases, Ninth Revision, Clinical Modification, principal diagnosis code of cardiorespiratory arrest (427.5) or ventricular fibrillation (VF) (427.41). In 4 predefined federal geographic regions: Northeast, Midwest, South, and West, means and proportions of survival, survival stratified by initial rhythm, hospital charges, and cost were estimated. Multiple linear and logistic regression models were conducted. Of the 154,177 patients with out-of-hospital cardiac arrest hospitalized in the United States, 25,873 (16.8%) were in the Northeast, 38,296 (24.8%) in the Midwest, 57,305 (37.2%) in the South, and 32,703 (21.2%) in the West. Variability in survival was noted in VF arrests; compared with the Northeast, survival was higher in the Midwest and South (adjusted odds ratio [AOR] 1.16, 95% confidence interval [CI] 1.02 to 1.32 and AOR 1.24, 95% CI 1.09 to 1.40, respectively), with no difference detected in the West (AOR 0.93, 95% CI 0.82 to 1.06). No variability in survival was noted after non-VF arrests (p >0.05). Hospital charges rose significantly across all regions of the United States (p-trend < 0.001) and were higher in the West compared with the Northeast (hospital charges >$109,000/admission, AOR 1.76; 95% CI 1.50 to 2.06). In conclusion, nationwide, we observed significant regional variability in survival of hospitalized patients after out of hospital VF cardiac arrest, no survival variability after non-VF arrests, and a steady increase in hospital charges.

Text mining applied to electronic cardiovascular procedure reports to identify patients with trileaflet aortic stenosis and coronary artery disease

BACKGROUND

Interrogation of the electronic health record (EHR) using billing codes as a surrogate for diagnoses of interest has been widely used for clinical research. However, the accuracy of this methodology is variable, as it reflects billing codes rather than severity of disease, and depends on the disease and the accuracy of the coding practitioner. Systematic application of text mining to the EHR has had variable success for the detection of cardiovascular phenotypes. We hypothesize that the application of text mining algorithms to cardiovascular procedure reports may be a superior method to identify patients with cardiovascular conditions of interest.

METHODS

We adapted the Oracle product Endeca, which utilizes text mining to identify terms of interest from a NoSQL-like database, for purposes of searching cardiovascular procedure reports and termed the tool "PennSeek". We imported 282,569 echocardiography reports representing 81,164 individuals and 27,205 cardiac catheterization reports representing 14,567 individuals from non-searchable databases into PennSeek. We then applied clinical criteria to these reports in PennSeek to identify patients with trileaflet aortic stenosis (TAS) and coronary artery disease (CAD). Accuracy of patient identification by text mining through PennSeek was compared with ICD-9 billing codes.

RESULTS

Text mining identified 7115 patients with TAS and 9247 patients with CAD. ICD-9 codes identified 8272 patients with TAS and 6913 patients with CAD. 4346 patients with AS and 6024 patients with CAD were identified by both approaches. A randomly selected sample of 200-250 patients uniquely identified by text mining was compared with 200-250 patients uniquely identified by billing codes for both diseases. We demonstrate that text mining was superior, with a positive predictive value (PPV) of 0.95 compared to 0.53 by ICD-9 for TAS, and a PPV of 0.97 compared to 0.86 for CAD.

CONCLUSION

These results highlight the superiority of text mining algorithms applied to electronic cardiovascular procedure reports in the identification of phenotypes of interest for cardiovascular research.

Relation Between Ventricular Premature Complexes and Incident Heart Failure

Ventricular premature complexes (VPCs) may represent a reversible cause of heart failure (HF); however, the type of patients most prone remains unknown. This study leverages a large population-based database to examine interactions that might prove clinically useful in risk-stratifying patients with VPCs. We used the California Healthcare Cost and Utilization Project to identify patients with VPCs and incident systolic HF from January 1, 2005, to December 31, 2009. We calculated hazard ratios for predictors of incident systolic HF using multivariable Cox proportional hazard models. Interactions with known risk factors were studied. Of the 16.8 million patients experiencing 48.1 million hospitalizations, 35,817 (0.2%) had a VPC diagnosis and 198,818 (1.2%) developed systolic HF. Incidence of systolic HF was 62.8 per 1,000 patient-years (95% confidence interval [CI] 61.2 to 64.4) in those with and 6.1 per 1,000 patient-years (95% CI 6.1 to 6.2) in those without VPCs (p <0.001). After adjusting for potential confounders, VPCs were associated with a nearly twofold risk of systolic HF (HR 1.8, 95% CI 1.8 to 1.9, p <0.001). Interaction analyses revealed a stronger relation between VPCs and HF among those with fewer cardiovascular risk factors. A VPC diagnosis in younger patients (<65 years) without coronary artery disease, hypertension, diabetes, or atrial fibrillation exhibited a sixfold increased risk of systolic HF (HR 6.5, 95% CI 5.5 to 7.7, p <0.001). In conclusion, these results suggest that a diagnosis of VPCs independently predicts incident systolic HF. This effect is most pronounced in younger patients without co-morbidities, suggesting that VPCs may be an important cause of "idiopathic" HF.

Allopurinol and the risk of ventricular arrhythmias in the elderly: a study using US Medicare data

BACKGROUND

There are no published human studies investigating whether the use of allopurinol, the most commonly used medication for the treatment of hyperuricemia in gout, the most common type of inflammatory arthritis in adults, has any beneficial effects on ventricular electrophysiology. The objective of our study was to assess whether allopurinol use is associated with a reduction in the risk of ventricular arrhythmias (VA).

METHODS

We used the 5% random sample of Medicare beneficiaries from 2006-2012 to examine new allopurinol use and the risk of incident VA. Multivariable Cox regression analyses were adjusted for demographics (age, race, sex), comorbidity, cardiac medications, and conditions associated with VA. We calculated hazard ratios (HR) and 95% confidence intervals (CI).

RESULTS

Of the 28,755 episodes of new allopurinol use, 2538 were associated with incident VA (8.8%). Among patients with incident VA, 54% were male, 78% were White, 75% had gout as the underlying diagnosis, and the mean Charlson-Romano comorbidity score was 4.8. The crude incidence of VA per 1,000,000 person-days declined as the duration of allopurinol use increased: 1-180 days, 151; 181 days to 2 years, 105; and > 2 years, 85. In multivariable-adjusted analyses, compared to non-use, allopurinol use was associated with lower HR of VA of 0.82 (95% CI, 0.76-0.90). Compared to allopurinol non-use, longer allopurinol use durations were significantly associated with lower multivariable-adjusted HR for VA: 1-180 days, 0.96 (95% CI, 0.85-1.08); 181 days to 2 years, 0.76 (95% CI, 0.68-0.85); and > 2 years, 0.72 (95% CI, 0.60-0.87). Multiple sensitivity analyses adjusting for cardiac conditions, anti-arrhythmic drugs and alternate definitions confirmed our findings with minimal/no attenuation of estimates.

CONCLUSION

Allopurinol use and use duration of more than 6 months were independently associated with a lower risk of VA. Future studies need to assess the pathophysiology of this potential benefit.

Comparative Risk of Ventricular Arrhythmia and Sudden Cardiac Death Across Antidepressants in Patients With Depressive Disorders

OBJECTIVE

We aimed to evaluate the risk of ventricular arrhythmia (VA) and/or sudden cardiac death (SCD) associated with antidepressant use.

METHODS

A cohort study was conducted using data from Taiwan's National Health Insurance Research Database from 2001 to 2012. A total of 793,460 new antidepressant users with depressive disorders were enrolled in the study. Outcomes were defined as the first principal diagnosis of VA or SCD in the emergency department or hospital discharge records. Cox proportional hazards models with stratification of propensity score deciles were used to evaluate the relative risk of VA/SCD for antidepressants compared with selective serotonin reuptake inhibitors (SSRIs).

RESULTS

A total of 245 VA/SCD events occurred. The incidence rate of VA/SCD among antidepressant users was 1.5 per 1000 person-years (95% confidence interval [CI], 1.3-1.7). Compared with SSRIs, the risk of VA/SCD was significantly lower for tricyclic or tetracyclic antidepressant (TCAs) (adjusted hazards ratio [aHR], 0.54; 95% CI, 0.36-0.83), but not other antidepressant classes. However, use of moderate- to high-dose TCAs carried a higher risk than low-dose TCAs (aHR, 4.37; 95% CI, 1.23-15.60). Antidepressant polypharmacy was associated with an increased risk of VA/SCD (aHR, 1.63; 95% CI, 1.07-2.49).

CONCLUSIONS

There was no difference in VA/SCD risk across antidepressant classes except that TCAs were associated with a lower risk than SSRIs. However, the observed comparative risk of TCAs might be attributable to low-dose TCA use, which is quite common in current clinical practice. It would be of importance to carry out further investigations to scrutinize the influence of antidepressants on VA/SCD.

Validity of peptic ulcer disease and upper gastrointestinal bleeding diagnoses in administrative databases: a systematic review protocol

INTRODUCTION

Administrative healthcare databases are useful to investigate the epidemiology, health outcomes, quality indicators and healthcare utilisation concerning peptic ulcers and gastrointestinal bleeding, but the databases need to be validated in order to be a reliable source for research. The aim of this protocol is to perform the first systematic review of studies reporting the validation of International Classification of Diseases, 9th Revision and 10th version (ICD-9 and ICD-10) codes for peptic ulcer and upper gastrointestinal bleeding diagnoses.

METHODS AND ANALYSIS

MEDLINE, EMBASE, Web of Science and the Cochrane Library databases will be searched, using appropriate search strategies. We will include validation studies that used administrative data to identify peptic ulcer disease and upper gastrointestinal bleeding diagnoses or studies that evaluated the validity of peptic ulcer and upper gastrointestinal bleeding codes in administrative data. The following inclusion criteria will be used: (a) the presence of a reference standard case definition for the diseases of interest; (b) the presence of at least one test measure (eg, sensitivity, etc) and (c) the use of an administrative database as a source of data. Pairs of reviewers will independently abstract data using standardised forms and will evaluate quality using the checklist of the Standards for Reporting of Diagnostic Accuracy (STARD) criteria. This systematic review protocol has been produced in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocol (PRISMA-P) 2015 statement.

ETHICS AND DISSEMINATION

Ethics approval is not required given that this is a protocol for a systematic review. We will submit results of this study to a peer-reviewed journal for publication. The results will serve as a guide for researchers validating administrative healthcare databases to determine appropriate case definitions for peptic ulcer disease and upper gastrointestinal bleeding, as well as to perform outcome research using administrative healthcare databases of these conditions.

TRIAL REGISTRATION NUMBER

CRD42015029216.

The rising prevalence and incidence of gout in British Columbia, Canada: Population-based trends from 2000 to 2012

OBJECTIVES

Gout is increasingly recognized as the most common form of inflammatory arthritis worldwide; however, no Canadian data on the disease burden of gout are available. We estimated the prevalence, incidence, prescription patterns, and comorbidity burden of gout in an entire Canadian province [British Columbia (BC)] over the last decade.

METHODS

We utilized PopulationData BC, a province-wide database, to estimate temporal trends in the prevalence and incidence of gout from 2000 to 2012, as well as according to age category. Annual estimates were age-sex-standardized using 2012 as the reference. We also examined annual trends in prescription patterns of common gout medications and assessed the comorbidity burden among gout patients in 2012.

RESULTS

The 2012 prevalence of gout was 3.8% among the overall population, and the incidence rate was 2.9 per 1000 person-years. Both gout prevalence and incidence increased substantially over the study period. This burden additionally increased according to age category, affecting over 8% of those ages 60-69 years in 2012. Approximately 22% of gout patients received a prescription for urate-lowering therapy (ULT), which remained stable over the study period, while colchicine and oral glucocorticoid use both increased modestly. By 2012, 72%, 52%, and 18% of prevalent gout patients had been diagnosed with hypertension, hyperlipidemia, and diabetes, respectively.

CONCLUSIONS

The burden of gout in BC, Canada, is substantial, and both the prevalence and incidence have increased over the past decade, while prescription of ULT remains low. These data support the need to improve gout prevention and care.