Natalie McCormick

Validity of myocardial infarction diagnoses in administrative databases: a systematic review.

Background Though administrative databases are increasingly being used for research related to myocardial infarction (MI), the validity of MI diagnoses in these databases has never been synthesized on a large scale. Objective To conduct the first systematic review of studies reporting on the validity of diagnostic codes for identifying MI in administrative data. Methods MEDLINE and EMBASE were searched (inception to November 2010) for studies: (a) Using administrative data to identify MI; or (b) Evaluating the validity of MI codes in administrative data; and (c) Reporting validation statistics (sensitivity, specificity, positive predictive value (PPV), negative predictive value, or Kappa scores) for MI, or data sufficient for their calculation. Additonal articles were located by handsearch (up to February 2011) of original papers. Data were extracted by two independent reviewers; article quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies tool. Results Thirty studies published from 1984–2010 were included; most assessed codes from the International Classification of Diseases (ICD)-9th revision. Sensitivity and specificity of hospitalization data for identifying MI in most [≥50%] studies was ≥86%, and PPV in most studies was ≥93%. The PPV was higher in the more-recent studies, and lower when criteria that do not incorporate cardiac troponin levels (such as the MONICA) were employed as the gold standard. MI as a cause-of-death on death certificates also demonstrated lower accuracy, with maximum PPV of 60% (for definite MI). Conclusions Hospitalization data has higher validity and hence can be used to identify MI, but the accuracy of MI as a cause-of-death on death certificates is suboptimal, and more studies are needed on the validity of ICD-10 codes. When using administrative data for research purposes, authors should recognize these factors and avoid using vital statistics data if hospitalization data is not available to confirm deaths from MI.

Validity of Diagnostic Codes for Acute Stroke in Administrative Databases: A Systematic Review

Objective To conduct a systematic review of studies reporting on the validity of International Classification of Diseases (ICD) codes for identifying stroke in administrative data. Methods MEDLINE and EMBASE were searched (inception to February 2015) for studies: (a) Using administrative data to identify stroke; or (b) Evaluating the validity of stroke codes in administrative data; and (c) Reporting validation statistics (sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), or Kappa scores) for stroke, or data sufficient for their calculation. Additional articles were located by hand search (up to February 2015) of original papers. Studies solely evaluating codes for transient ischaemic attack were excluded. Data were extracted by two independent reviewers; article quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies tool. Results Seventy-seven studies published from 1976–2015 were included. The sensitivity of ICD-9 430-438/ICD-10 I60-I69 for any cerebrovascular disease was ≥ 82% in most [≥ 50%] studies, and specificity and NPV were both ≥ 95%. The PPV of these codes for any cerebrovascular disease was ≥ 81% in most studies, while the PPV specifically for acute stroke was ≤ 68%. In at least 50% of studies, PPVs were ≥ 93% for subarachnoid haemorrhage (ICD-9 430/ICD-10 I60), 89% for intracerebral haemorrhage (ICD-9 431/ICD-10 I61), and 82% for ischaemic stroke (ICD-9 434/ICD-10 I63 or ICD-9 434&436). For in-hospital deaths, sensitivity was 55%. For cerebrovascular disease or acute stroke as a cause-of-death on death certificates, sensitivity was ≤ 71% in most studies while PPV was ≥ 87%. Conclusions While most cases of prevalent cerebrovascular disease can be detected using 430-438/I60-I69 collectively, acute stroke must be defined using more specific codes. Most in-hospital deaths and death certificates with stroke as a cause-of-death correspond to true stroke deaths. Linking vital statistics and hospitalization data may improve the ascertainment of fatal stroke.

Validity of heart failure diagnoses in administrative databases: a systematic review and meta-analysis.

Objective Heart failure (HF) is an important covariate and outcome in studies of elderly populations and cardiovascular disease cohorts, among others. Administrative data is increasingly being used for long-term clinical research in these populations. We aimed to conduct the first systematic review and meta-analysis of studies reporting on the validity of diagnostic codes for identifying HF in administrative data. Methods MEDLINE and EMBASE were searched (inception to November 2010) for studies: (a) Using administrative data to identify HF; or (b) Evaluating the validity of HF codes in administrative data; and (c) Reporting validation statistics (sensitivity, specificity, positive predictive value [PPV], negative predictive value, or Kappa scores) for HF, or data sufficient for their calculation. Additional articles were located by hand search (up to February 2011) of original papers. Data were extracted by two independent reviewers; article quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies tool. Using a random-effects model, pooled sensitivity and specificity values were produced, along with estimates of the positive (LR+) and negative (LR−) likelihood ratios, and diagnostic odds ratios (DOR = LR+/LR−) of HF codes. Results Nineteen studies published from1999–2009 were included in the qualitative review. Specificity was ≥95% in all studies and PPV was ≥87% in the majority, but sensitivity was lower (≥69% in ≥50% of studies). In a meta-analysis of the 11 studies reporting sensitivity and specificity values, the pooled sensitivity was 75.3% (95% CI: 74.7–75.9) and specificity was 96.8% (95% CI: 96.8–96.9). The pooled LR+ was 51.9 (20.5–131.6), the LR− was 0.27 (0.20–0.37), and the DOR was 186.5 (96.8–359.2). Conclusions While most HF diagnoses in administrative databases do correspond to true HF cases, about one-quarter of HF cases are not captured. The use of broader search parameters, along with laboratory and prescription medication data, may help identify more cases.

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.

Do inhaled corticosteroids protect against lung cancer in patients with COPD? A systematic review

Inhaled corticosteroids (ICS) are commonly prescribed to COPD patients, particularly those with more advanced stages of the disease. These patients are also at increased risk of lung cancer. A systematic review was undertaken to identify studies that examined the association between lung cancer risk and ICS therapy in COPD patients. The search strategy was created in MEDLINE and extended to EMBASE as well as other relevant databases. Both randomized controlled trials (RCTs) and observational studies were considered for inclusion. Studies were required to have incident lung cancer or deaths from lung cancer as an outcome in order to be included in the review. Six studies met the inclusion criteria. Two observational studies directly addressed the specific research. Four RCTs presented sufficient data to calculate the relative risk of lung cancer in COPD patients. None of the identified RCTs showed a statistically significant association of ICS use with lung cancer risk. Observational studies showed a protective effect from ICS use, particularly at high doses. Given the observational evidence and the low numbers of lung cancer events in the RCTs, these results may be prone to type II error. The observational studies dealt with very specific patient populations and exposure definitions, which might not have adequately captured the complex relationship between ICS exposure and lung cancer risk. Results from RCTs suggest no effect of ICS on the risk of lung cancer. However, results from observational studies suggest the potential that ICS may confer a protective effect, particularly at high doses.

Trends in Gout and Rheumatoid Arthritis Hospitalizations in Canada from 2000‐2011

Gout and rheumatoid arthritis (RA) are the 2 most common forms of inflammatory arthritis worldwide. As hospitalizations for both conditions lead to substantial health resource use, contemporary inpatient trends and associated costs may provide important benchmarks of disease burden. However, relevant data are limited.

Incremental direct medical costs of systemic lupus erythematosus patients in the years preceding diagnosis: A general population-based study

Objective We estimated the incremental (extra) direct medical costs of a population-based cohort of newly diagnosed systemic lupus erythematosus (SLE) for five years before and after diagnosis, and the impact of sex and socioeconomic status (SES) on pre-index costs for SLE. Methods We identified all adults newly diagnosed with SLE over 2001–2010 in British Columbia, Canada, and obtained a sample of non-SLE individuals from the general population, matched on sex, age, and calendar-year of study entry. We captured costs for all outpatient encounters, hospitalisations, and dispensed medications each year. Using generalised linear models, we estimated incremental costs of SLE each year before/after diagnosis (difference in costs between SLE and non-SLE, controlling for covariates). Similar models were used to examine the impact of sex and SES on costs within SLE. Results We included 3632 newly diagnosed SLE (86% female, mean age 49.6 ± 15.9) and 18,060 non-SLE individuals. Over the five years leading up to diagnosis, per-person healthcare costs for SLE patients increased year-over-year by 35%, on average, with the biggest increases in the final two years by 39% and 97%, respectively. Per-person all-cause medical costs for SLE the year after diagnosis (Year + 1) averaged C

Excess Productivity Costs of Systemic Lupus Erythematosus, Systemic Sclerosis, and Sjogren's Syndrome: A General Population‐Based Study

12,019 (2013 Canadian) with 58% from hospitalisations, 24% outpatient, and 18% from prescription medications; Year + 1 costs for non-SLE averaged C

Socioeconomic Predictors of Incident Depression in Systemic Lupus Erythematosus

2412. Following adjustment for age, sex, urban/rural residence, socioeconomic status, and prior years comorbidity score, SLE was associated with significantly greater hospitalisation, outpatient, and medication costs than non-SLE in each year of study. Altogether, adjusted incremental costs of SLE rose from C

THU0647 Longitudinal study of long-term poverty and persistent depressive symptoms in sle

1131 per person in Year –5 (fifth year before diagnosis) to C