Comparing the long-term outcomes in chronic coronary syndrome patients with prior ST-segment and non-ST-segment elevation myocardial infarction: findings from the TIGRIS registry

OBJECTIVES

Compared with ST-segment elevation myocardial infarction (STEMI) patients, non-STEMI (NSTEMI) patients have more comorbidities and extensive coronary artery disease. Contemporary comparative data on the long-term prognosis of stable post-myocardial infarction subtypes are needed.

DESIGN

Long-Term rIsk, clinical manaGement and healthcare Resource utilisation of stable coronary artery dISease (TIGRIS) was a multinational, observational and longitudinal cohort study.

SETTING

Patients were enrolled from 350 centres, with >95% coming from cardiology practices across 24 countries, from 19 June 2013 to 31 March 2017.

PARTICIPANTS

This study enrolled 8277 stable patients 1-3 years after myocardial infarction with ≥1 additional risk factor.

OUTCOME MEASURES

Over a 2 year follow-up, cardiovascular events and deaths and self-reported health using the EuroQol 5-dimension questionnaire score were recorded. Relative risk of clinical events and health resource utilisation in STEMI and NSTEMI patients were compared using multivariable Poisson regression models, adjusting for prognostically relevant patient factors.

RESULTS

Of 7752 patients with known myocardial infarction type, 46% had NSTEMI; NSTEMI patients were older with more comorbidities than STEMI patients. NSTEMI patients had significantly poorer self-reported health and lower prevalence of dual antiplatelet therapy at hospital discharge and at enrolment 1-3 years later. NSTEMI patients had a higher incidence of combined myocardial infarction, stroke and cardiovascular death (5.6% vs 3.9%, p<0.001) and higher all-cause mortality (4.2% vs 2.6%, p<0.001) compared with STEMI patients. Risks were attenuated after adjusting for other patient characteristics. Health resource utilisation was higher in NSTEMI patients, although STEMI patients had more cardiologist visits.

CONCLUSIONS

Post-NSTEMI chronic coronary syndrome patients had a less favourable risk factor profile, poorer self-reported health and more adverse cardiovascular events during long-term follow-up than individuals post STEMI. Efforts are needed to recognise the risks of stable patients after NSTEMI and optimise secondary prevention and care.

TRIAL REGISTRATION NUMBER

NCT01866904.

Evolution of economic burden of heart failure by ejection fraction in newly diagnosed patients in Spain

OBJECTIVE

To describe healthcare resource utilization (HCRU) and costs, in patients with newly diagnosed heart failure (HF) according to ejection fraction (EF) in Spain.

METHODS

Retrospective cohort study that analyzed anonymized, integrated and computerised medical records in Spain. Patients with ≥ 1 new HF diagnosis between January 2013 and September 2019 were included and followed-up during a 4-year period. Rates per 100 person-years of HCRU and costs were estimated.

RESULTS

Nineteen thousand nine hundred sixty-one patients were included, of whom 43.5%, 26.3%, 5.1% and 25.1% had HF with reduced, preserved, mildly reduced and unknown EF, respectively. From year 1 to 4, HF rates of outpatient visits decreased from 1149.5 (95% CI 1140.8-1159.3) to 765.5 (95% CI 745.9-784.5) and hospitalizations from 61.7 (95% CI 60.9-62.7) to 15.7(14.7-16.7) per 100 person-years. The majority of HF-related healthcare resource costs per patient were due to hospitalizations (year 1-4: 63.3-38.2%), followed by indirect costs (year 1-4: 12.2-29.0%), pharmacy (year 1-4: 11.9-19.9%), and outpatient care (year 1-4: 12.6-12.9%). Mean (SD) per patient HF-related costs decreased from 2509.6 (3518.5) to 1234.6 (1534.1) Euros (50% cost reduction). At baseline, 70.1% were taking beta-blockers, 56.3% renin-angiotensin system inhibitors, 11.8% mineralocorticoid receptor antagonists and 8.9% SGLT2 inhibitors. At 12 months, these numbers were 72.3%, 65.4%, 18.9% and 9.8%, respectively.

CONCLUSIONS

Although the economic burden of HF decreased over time since diagnosis, it is still substantial. This reduction could be partially related to a survival bias (sick patients died early), but also to a better HF management. Despite that, there is still much room for improvement.

Evaluating clinical outcomes and prognosis in patients with cirrhosis and portal hypertension: a retrospective observational cohort study

OBJECTIVE

Cirrhosis describes the end-stage of chronic liver disease. Irreversible changes in the liver cause portal hypertension, which can progress to serious complications and death. Only a few studies with small sample sizes have investigated the prognosis of cirrhosis with portal hypertension. We used electronic healthcare records to examine liver-related outcomes in patients with diagnosed/suspected portal hypertension.

DESIGN

This retrospective observational cohort study used secondary health data between 1 January 2017 and 3 December 2020 from the TriNetX Network, a federated electronic healthcare records platform. Three patient groups with cirrhosis and diagnosed/suspected portal hypertension were identified ('most severe', 'moderate severity' and 'least severe'). Outcomes studied individually and as a composite were variceal haemorrhage, hepatic encephalopathy, complications of ascites and recorded mortality up to 24 months.

RESULTS

There were 13 444, 23 299, and 23 836 patients in the most severe, moderate severity and least severe groups, respectively. Mean age was similar across groups; most participants were white. The most common individual outcomes at 24 months were variceal haemorrhage in the most severe group, recorded mortality and hepatic encephalopathy in the moderate severity group, and recorded mortality in the least severe group. Recorded mortality rate was similar across groups. For the composite outcome, cumulative incidence was 59% in the most severe group at 6 months. Alcohol-associated liver disease and metabolic-associated steatohepatitis were significantly associated with the composite outcome across groups.

CONCLUSION

Our analysis of a large dataset from electronic healthcare records illustrates the poor prognosis of patients with diagnosed/suspected portal hypertension.

Long-term outcomes among stable post-acute myocardial infarction patients living in rural versus urban areas: insights from the prospective, observational TIGRIS registry

BACKGROUND

Insights on the differences in clinical outcomes, quality of life (QoL) and health resource utilisation (HRU) with different levels of care available to post-acute myocardial infarction (AMI) populations in rural and urban settings are limited.

METHODS

The long-Term rIsk, clinical manaGement, and healthcare Resource utilisation of stable coronary artery dISease (TIGRIS), a prospective, observational registry, enrolled 8452 patients aged ≥50 years 1-3 years post-AMI from June 2013 to November 2014 from 24 countries in Asia Pacific/Australia, Europe, North America and South America. Differences in QoL (measured using the EuroQol Research Foundation instrument) and HRU between patients in rural and urban settings were evaluated in this post hoc analysis. The incidence of clinical endpoints (cardiovascular (CV) death, AMI, unstable angina with urgent revascularisation and stroke; bleeding; and all-cause mortality) was analysed. Data were collected at baseline and every 6 months for 24 months.

RESULTS

There were fewer hospitalisations and visits to general practitioners (GPs) and cardiologists in the rural versus urban populations (adjusted event rate ratio (ERR)=0.90 (95% CI, 0.82 to 1.00, p=0.04); ERR=0.84 (95% CI, 0.78 to 0.92, p<0.001); ERR=0.86 (95% CI, 0.81 to 0.92, p<0.001), respectively). No statistically significant differences were observed between rural and urban populations in all-cause death, AMI, unstable angina with urgent revascularisation, CV death, stroke, major bleeding events and health-related QoL. The adjusted incidence rate ratio was 0.92 (95% CI, 0.74 to 1.15) for the composite of CV death, AMI and stroke.

CONCLUSIONS

Living in rural areas was associated with fewer GP/cardiologist visits and hospitalisations; no significant differences in clinical outcomes and QoL were observed.

TRIAL REGISTRATION NUMBER

NCT01866904.

Burden of Illness beyond Mortality and Heart Failure Hospitalizations in Patients Newly Diagnosed with Heart Failure in Spain According to Ejection Fraction

OBJECTIVE

The objective of this study was to describe the rates of adverse clinical outcomes, including all-cause mortality, heart failure (HF) hospitalization, myocardial infarction, and stroke, in patients newly diagnosed with HF to provide a comprehensive picture of HF burden.

METHODS

This was a retrospective and observational study, using the BIG-PAC database in Spain. Adults, newly diagnosed with HF between January 2013 and September 2019 with ≥1 HF-free year of enrolment prior to HF diagnosis, were included.

RESULTS

A total of 19,961 patients were newly diagnosed with HF (43.5% with reduced ejection fraction (EF), 26.3% with preserved EF, 5.1% with mildly reduced EF, and 25.1% with unknown EF). The mean age was 69.7 ± 19.0 years; 53.8% were men; and 41.0% and 41.5% of patients were in the New York Heart Association functional classes II and III, respectively. The baseline HF treatments included beta-blockers (70.1%), renin-angiotensin system inhibitors (56.3%), mineralocorticoid receptor antagonists (11.8%), and SGLT2 inhibitors (8.9%). The post-index incidence rates of all-cause mortality, HF hospitalization, and both combined were 102.2 (95% CI 99.9-104.5), 123.1 (95% CI 120.5-125.7), and 182 (95% CI 178.9-185.1) per 1000 person-years, respectively. The rates of myocardial infarction and stroke were lower (26.2 [95% CI 25.1-27.4] and 19.8 [95% CI 18.8-20.8] per 1000 person-years, respectively).

CONCLUSIONS

In Spain, patients newly diagnosed with HF have a high risk of clinical outcomes. Specifically, the rates of all-cause mortality and HF hospitalization are high and substantially greater than the rates of myocardial infarction and stroke. Given the burden of adverse outcomes, these should be considered targets in the comprehensive management of HF. There is much room for improving the proportion of patients receiving disease-modifying therapies.

Post-Authorization Safety Studies of Acute Liver Injury and Severe Complications of Urinary Tract Infection in Patients with Type 2 Diabetes Exposed to Dapagliflozin in a Real-World Setting

INTRODUCTION

At the time of dapagliflozin's approval in Europe (2012) to treat patients with type 2 diabetes mellitus, concerns regarding acute liver injury and severe complications of urinary tract infection (sUTI) led to two post-authorization safety (PAS) studies of these outcomes to monitor the safety of dapagliflozin in real-world use.

OBJECTIVE

To investigate the incidence of hospitalization for acute liver injury (hALI) or sUTI (pyelonephritis or urosepsis) among patients initiating dapagliflozin compared with other glucose-lowering drugs (GLDs).

METHODS

These two noninterventional cohort studies identified initiators of dapagliflozin and comparator GLDs in November 2012-February 2019 using data from three longitudinal, population-based data sources: Clinical Practice Research Datalink (UK), the HealthCore Integrated Research Database (USA), and the Medicare database (USA). Outcomes (hALI and sUTI) were identified with electronic algorithms. Incidence rates were estimated by exposure group. Incidence rate ratios (IRRs) were calculated comparing dapagliflozin to comparator GLDs, using propensity score trimming and stratification to address confounding. The sUTI analyses were conducted separately by sex.

RESULTS

In all data sources, hALI and sUTI incidence rates were generally lower in dapagliflozin initiators than comparator GLD initiators. The adjusted IRR (95% confidence interval) pooled across data sources for hALI was 0.85 (0.59-1.24) and for sUTI was 0.76 (0.60-0.96) in females and 0.74 (0.56-1.00) in males. Findings from sensitivity analyses were largely consistent with the primary analyses.

CONCLUSIONS

These real-world studies do not suggest increased risks of hALI or sUTI, and they suggest a potential decreased risk of sUTI with dapagliflozin exposure compared with other GLDs.

Healthcare resource utilization and costs among patients with heart failure with preserved, mildly reduced, and reduced ejection fraction in Spain

AIMS

To describe healthcare resource utilization (HCRU) of patients with heart failure with preserved (HFpEF), mildly reduced (HFmrEF), and reduced ejection fraction (HFrEF) in Spain.  METHODS: Adults with ≥ 1 HF diagnosis and ≥ 1 year of continuous enrolment before the corresponding index date (1/January/2016) were identified through the BIG-PAC database. Rate per 100 person-years of all-cause and HF-related HCRU during the year after the index date were estimated using bootstrapping with replacement.

RESULTS

Twenty-one thousand two hundred ninety-seven patients were included, of whom 48.5% had HFrEF, 38.6% HFpEF and 4.2% HFmrEF, with the rest being of unknown EF. Mean age was 78.8 ± 11.8 years, 53.0% were men and 83.0% were in NYHA functional class II/III. At index, 67.3% of patients were taking renin angiotensin system inhibitors, 61.2% beta blockers, 23.4% aldosterone antagonists and 5.2% SGLT2 inhibitors. Rates of HF-related outpatient visits and hospitalization were 968.8 and 51.6 per 100 person-years, respectively. Overall, 31.23% of patients were hospitalized, mainly because of HF (87.88% of total hospitalizations); HF hospitalization length 21.06 ± 17.49 days (median 16; 25th, 75th percentile 9-27). HF hospitalizations were the main cost component: inpatient 73.64%, pharmacy 9.67%, outpatient 9.43%, and indirect cost 7.25%. Rates of all-cause and HF-related HCRU and healthcare cost were substantial across all HF subgroups, being higher among HFrEF compared to HFmrEF and HFpEF patients.

CONCLUSIONS

HCRU and cost associated with HF are high in Spain, HF hospitalizations being the main determinant. Medication cost represented only a small proportion of total costs, suggesting that an optimization of HF therapy may reduce HF burden.

Prevalence, Characteristics, Management and Outcomes of Patients with Heart Failure with Preserved, Mildly Reduced, and Reduced Ejection Fraction in Spain

Objective: To estimate the prevalence, incidence, and describe the characteristics and management of patients with heart failure with preserved (HFpEF), mildly reduced (HFmrEF), and reduced ejection fraction (HFrEF) in Spain. Methods: Adults with ≥1 inpatient or outpatient HF diagnosis between 1 January 2013 and 30 September 2019 were identified through the BIG-PAC database. Annual incidence and prevalence by EF phenotype were estimated. Characteristics by EF phenotype were described in the 2016 and 2019 HF prevalent cohorts and outcomes in the 2016 HF prevalent cohort. Results: Overall, HF incidence and prevalence were 0.32/100 person-years and 2.34%, respectively, but increased every year. In 2019, 49.3% had HFrEF, 38.1% had HFpEF, and 4.3% had HFmrEF (in 8.3%, EF was not available). Compared with HFrEF, patients with HFpEF were largely female, older, and had more atrial fibrillation but less atherosclerotic cardiovascular disease. Among patients with HFrEF, 76.3% were taking renin-angiotensin system inhibitors, 69.5% beta-blockers, 36.8% aldosterone antagonists, 12.5% sacubitril/valsartan and 6.7% SGLT2 inhibitors. Patients with HFpEF and HFmrEF took fewer HF drugs compared to HFrEF. Overall, the event rates of HF hospitalization were 231.6/1000 person-years, which is more common in HFrEF patients. No clinically relevant differences were found in patients with HFpEF, regardless EF (50- < 60% vs. ≥60%). Conclusions: >2% of patients have HF, of which around 50% have HFrEF and 40% have HFpEF. The prevalence of HF is increasing over time. Clinical characteristics by EF phenotype are consistent with previous studies. The risk of outcomes, particularly HF hospitalization, remains high, likely related to insufficient HF treatment.

Differences between patients with type 1 diabetes with optimal and suboptimal glycaemic control: A real-world study of more than 30 000 patients in a US electronic health record database

AIMS

To use electronic health record data from real-world clinical practice to assess demographics, clinical characteristics and disease burden of adults with type 1 diabetes (T1D) in the United States.

MATERIALS AND METHODS

Retrospective observational study of adults with T1D for ≥24 months at their first visit with a T1D diagnosis code ("index date") between July 2014 and June 2016 in the Optum Humedica database. Demographic characteristics, acute complications (severe hypoglycaemia [SH], diabetic ketoacidosis [DKA]), microvascular complications, cardiovascular (CV) events and health care resource utilization during the 12 months before the index date ("baseline period") were compared between patients with optimal versus suboptimal glycaemic control (glycated haemoglobin [HbA1c] <7.0% vs. ≥7.0% [53 mmol/mol]) at the closest measurement to the index date.

RESULTS

Of 31 430 adults with T1D, 79.9% had suboptimal glycaemic control (mean HbA1c 8.8% [73 mmol/mol]). These patients were more likely to be younger, African American, uninsured or on Medicaid, obese, smokers, have uncontrolled hypertension and have depression. Despite worse glycaemic control and increased CV risk factors of uncontrolled hypertension, obesity and smoking, rates of coronary heart disease and stroke were not higher in these patients. Patients with suboptimal glycaemic control also experienced more diabetes complications (including SH, DKA and microvascular disease) and utilized more emergency care, with more emergency department visits and inpatient stays.

CONCLUSION

This real-world study of >30 000 adults with T1D showed that individuals with suboptimal versus optimal glycaemic control differed significantly in terms of health care coverage, comorbidities, diabetes-related complications, health care utilization and CV risk factors. However, suboptimal control was not associated with increased risk of CV outcomes.

Incidences of Severe Hypoglycemia and Diabetic Ketoacidosis and Prevalence of Microvascular Complications Stratified by Age and Glycemic Control in U.S. Adult Patients With Type 1 Diabetes: A Real-World Study

OBJECTIVE

To assess the burden of disease for adults with type 1 diabetes in a U.S. electronic health record database by evaluating acute and microvascular complications stratified by age and glycemic control.

RESEARCH DESIGN AND METHODS

This is a retrospective observational study of adults with type 1 diabetes (1 July 2014-30 June 2016) classified using a validated algorithm, with disease duration ≥24 months and, during a 12-month baseline period, not pregnant and having one or more insulin prescriptions and one or more HbA_1c measurements. Demographic characteristics, acute complications (severe hypoglycemia [SH], diabetic ketoacidosis [DKA]), and microvascular complications (neuropathy, nephropathy, retinopathy) were stratified by age (18-25, 26-49, 50-64, ≥65 years) and glycemic control (HbA_1c <7%, 7% to <9%, ≥9%).

RESULTS

Of 31,430 patients, ∼20% had HbA_1c <7%. Older patients had lower HbA_1c values than younger patients (P < 0.001). Patients with poor glycemic control had the highest annual incidence of SH (4.2%, 4.0%, and 8.3%) and DKA (1.3%, 2.8%, and 15.8%) for HbA_1c <7%, 7% to <9%, and ≥9% cohorts, respectively (both P < 0.001), and a higher prevalence of neuropathy and nephropathy (both P < 0.001).

CONCLUSIONS

For adults with type 1 diabetes, glycemic control appears worse than previously estimated. Rates of all complications increased with increasing HbA_1c. Compared with HbA_1c <7%, HbA_1c ≥9% was associated with twofold and 12-fold higher incidences of SH and DKA, respectively. Younger adults had more pronounced higher risks of SH and DKA associated with poor glycemic control than older adults.

Time to Treatment Intensification After Monotherapy Failure and Its Association With Subsequent Glycemic Control Among 93,515 Patients With Type 2 Diabetes

OBJECTIVE

The goal of this study was to evaluate the association between the timing of treatment intensification and subsequent glycemic control among patients with type 2 diabetes in whom monotherapy fails.

RESEARCH DESIGN AND METHODS

This retrospective analysis of the U.K. Clinical Practice Research Datalink database focused on patients with type 2 diabetes and one or more HbA_1c measurements ≥7% (≥53 mmol/mol) after ≥3 months of metformin or sulfonylurea monotherapy (first measurement meeting these criteria was taken as the study index date). Baseline (6 months before the index date) characteristics were stratified by time from the index date to intensification (early: <12 months; intermediate: 12 to <24 months; late: 24 to <36 months). Intensification was defined as initiating after the index date one or more noninsulin antidiabetes medication in addition to metformin or a sulfonylurea. Association between time to intensification and subsequent glycemic control (first HbA_1c <7% [<53 mmol/mol] after intensification) was evaluated using Kaplan-Meier analyses and Cox proportional hazard models that accounted for baseline differences.

RESULTS

Of the 93,515 patients who met the study criteria (mean age 60 years; ∼59% male; 80% taking metformin), 23,761 (25%) intensified <12 months after the index date; 11,908 (13%) intensified after 12 to <24 months; and 7,146 (8%) intensified after 24 to <36 months. Patients who intensified treatment ≥36 months after the index date (n = 9,638 [10%]) and those with no evidence of treatment intensification during the observable follow-up period (n = 41,062 [44%]) were not included in further analyses. The median times from intensification to control were 20.0, 24.1, and 25.7 months, respectively, for the early, intermediate, and late intensification cohorts. After adjustment for baseline differences, the likelihood of attaining glycemic control was 22% and 28% lower for patients in the intermediate and late intensification groups, respectively, compared with those intensifying early (P < 0.0001).

CONCLUSIONS

Earlier treatment intensification is associated with shorter time to subsequent glycemic control, independent of whether patients initiate first-line treatment with metformin or a sulfonylurea.

Long-term cardiovascular risk and costs for myocardial infarction survivors in a US commercially insured population

OBJECTIVE

To quantify clinical and cost long-term outcomes in cardiovascular stable post-myocardial-infarction patients.

RESEARCH DESIGN AND METHODS

Subjects with a history of myocardial infarction (MI) who were 50-64 years old and MI- and stroke-free for ≥12 months (index date) were identified in a large US claims database. Individuals were followed for up to 5 years (mean: 2.0 years) after their index date.

MAIN OUTCOME MEASURES

Rates of MI, stroke, all-cause death, and a composite of these were analyzed via Cox regression models, adjusted for covariates. Results are reported for the overall population and the subgroups of those with type 2 diabetes, additional prior MI, and non-end-stage renal disease. As a secondary endpoint healthcare costs were evaluated at baseline and during each year of follow-up. Results Over the follow-up period, which averaged 2 years, 7.6% of all 13,492 subjects (10.5% vs. 5.4% with and without the selected risk factors, respectively) experienced at least one of the outcome events. The cumulative incidence rates over the entire follow-up period for the primary composite outcome were 20.8% and 12.2% for those with and without the selected atherothrombotic risk factors, respectively. The cardiovascular-related per-person-per-year healthcare costs during follow-up were higher in those with ≥1 additional risk factor compared to those without: $15,247 versus $7521. Costs were elevated over baseline costs throughout follow-up.

LIMITATIONS

Administrative claims data lack clinical detail. Generalizability of results is limited to the US commercially insured population of a similar age to that included in this study.

CONCLUSIONS

High risk MI survivors who have been event free for ≥1 year remained at substantial risk of CV events and had increased healthcare costs for up to 5 years post-MI. These long-term risks have not been previously demonstrated in a working-age US population and suggest an unmet need for continuing secondary prevention long-term post-MI.

Log-Linear Modeling of Agreement among Expert Exposure Assessors

BACKGROUND

Evaluation of expert assessment of exposure depends, in the absence of a validation measurement, upon measures of agreement among the expert raters. Agreement is typically measured using Cohen's Kappa statistic, however, there are some well-known limitations to this approach. We demonstrate an alternate method that uses log-linear models designed to model agreement. These models contain parameters that distinguish between exact agreement (diagonals of agreement matrix) and non-exact associations (off-diagonals). In addition, they can incorporate covariates to examine whether agreement differs across strata.

METHODS

We applied these models to evaluate agreement among expert ratings of exposure to sensitizers (none, likely, high) in a study of occupational asthma.

RESULTS

Traditional analyses using weighted kappa suggested potential differences in agreement by blue/white collar jobs and office/non-office jobs, but not case/control status. However, the evaluation of the covariates and their interaction terms in log-linear models found no differences in agreement with these covariates and provided evidence that the differences observed using kappa were the result of marginal differences in the distribution of ratings rather than differences in agreement. Differences in agreement were predicted across the exposure scale, with the likely moderately exposed category more difficult for the experts to differentiate from the highly exposed category than from the unexposed category.

CONCLUSIONS

The log-linear models provided valuable information about patterns of agreement and the structure of the data that were not revealed in analyses using kappa. The models' lack of dependence on marginal distributions and the ease of evaluating covariates allow reliable detection of observational bias in exposure data.

Mesothelioma and employment in massachusetts: analysis of cancer registry data 1988-2003

BACKGROUND

Cancer registries can be used to monitor mesothelioma cases and to identify occupations and industries previously and newly associated with mesothelioma-causing asbestos exposure by using standard registry data on the "usual" occupation and industry of the case.

METHODS

We used the National Institute for Occupational Safety and Health's Standardized Occupational Industry Coding Software to code 564 mesothelioma cases for occupation and 543 for industry of the 1,424 incident mesothelioma in the Massachusetts Cancer Registry from 1988 to 2003. Additionally, we coded the occupation and industry of 80,184 comparison cancer cases (35% of comparison cases in our database). These were used to compute Standardized Morbidity Odds Ratios (SMORs).

RESULTS

Seventeen occupations and 11 industries had statistically significant elevated SMORs for mesothelioma. Occupations and industries historically associated with mesothelioma remained elevated in these results. However, we also found statistically significant elevated SMORs for several occupations and industries for which there was previously weak or no association such as chemical engineers, machine operators, and automobile mechanics and machine manufacturing, railroads, and the U.S. Postal Service.

CONCLUSIONS

Incident cases of mesothelioma do not appear to be declining in Massachusetts, as legacy exposures to asbestos continue to produce cases in individuals involved in shipbuilding and construction. Exposures in occupations and industries not previously associated with mesothelioma also contribute cases. Cancer registries, with improved data collection, should continue to be monitored for mesothelioma cases and asbestos exposures.

Abstract 172: Projected Number of HF Admissions Per Heart Failure Patient In The Medicare Population

OBJECTIVES: Heart Failure (HF) is a leading cause of morbidity and mortality. Hospitalization for HF appears to be steadily increasing. We sought to identify HF patients and understand their patterns of care in the “real-world” through analysis of a retrospective observational database.

METHODS: Patients in the Medicare 5% database with a primary inpatient diagnosis of HF (428.0, 428.9, 428.20-23, 428.30-33, 428.40-43) during CY05-08 were included. Maximum follow-up was 33 months (6 months baseline, 3 month index and 24 months follow-up ). Minimum follow-up was 9 months . To exclude prevalent cases, patients were required to have no HF diagnoses during baseline. The quarter of the initial HF inpatient diagnosis was designated the “index”. Patients were followed for up to 2 years (8 Quarters) after the “index” or until death or enrolment end. Sub-cohorts were defined based on HF events experienced during follow-up: 0, 1, or 2 or more.

RESULTS: 43,819 patients with new primary HF inpatient claims were identified in the study period. Within the 27 month follow-up (includes “index”), the identified HF patients had 140,802 inpatient hospitalizations (3.2 per patient), of which 67,339 (1.54 per patient) had a primary HF diagnosis (includes index HF hospitalization). Out of the 43,819 patients included, only 10,166 (23.2%) had one or more HF hospitalization within two years after the index period. Patients who experienced one or more than one HF admission after “index” tended to have experienced more all-cause admissions. Mortality was 10.3% during “index”; 25.3% in Year 1 and 14.0% in Year 2. Total mortality was 42.4% (18,562 out of 43,819).

CONCLUSIONS: These results suggest that an early HF patient could be expected to get admitted on average 3.2 times for any cause over the next 2 years; 1.54 times for HF (47.8% of total). Mortality after the index HF admission was >40% over the same period. Our results further underline HF as a major clinical and economic burden in the US. More importantly, our results demonstrate that most of the economic burden is driven by a relatively small percentage of patients (23.2%); successful intervention in this subgroup could drastically reduce the burden of HF to Medicare.

Use of statewide electronic emergency department data for occupational injury surveillance: a feasibility study in Massachusetts

BACKGROUND

Statewide datasets of emergency department (ED) visits may be useful for occupational injury surveillance. Using data from 12 hospitals, we evaluated two indicators of work-relatedness in reported ED data and the availability of employment information in medical charts.

METHODS

Workers' compensation as payer and/or "yes" in an injury-at-work field were used to define probable work-related (PWR) injury visits in the Massachusetts ED dataset. Charts were reviewed for a sample of 1,002 PWR and 250 probable nonwork-related (PNWR) cases.

RESULTS

Using chart information as the gold standard, indicators of work-relatedness had a sensitivity of 82%, specificity of 97%, and predictive value positive of 86%. Employer name was in charts for 89% of PWR and 42% of PNWR cases. Occupation was available for 34% of PWR cases.

CONCLUSION

Electronic ED data are useful for state surveillance of occupational injuries. Improvements in attribution of work-relatedness and collection of available employer identifiers and occupational information would enhance its usefulness. The performance of indicators of work-relatedness in ED datasets should be examined in different states.

Deployment to a combat zone and other risk factors for mental health-related disability discharge from the U.S. Army: 1994-2007

Combat exposure is associated with subsequent mental health symptoms, but progression to mental health disability is unclear. Army soldiers discharged with mental health disability (n = 4,457) were compared to two matched control groups: other disability discharge (n = 8,974) and routine discharge (n = 9,128). In multivariate logistic models, odds of mental health disability discharge versus other disability and routine discharge were significantly higher for soldiers deployed to combat zones; odds ratios increased with deployment time. Prior mental health hospitalization decreased these odds, though they remained significantly elevated. Mental health hospitalization with successful treatment may facilitate better coping during deployment. The frequency of disability after mental health hospitalization suggests remaining gaps in deployment-related mental health assessment and treatment.

Completeness and accuracy of International Classification of Disease (ICD) external cause of injury codes in emergency department electronic data

The accuracy of external cause of injury codes (E codes) for work-related and non-work-related injuries in Massachusetts emergency department data were evaluated. Medical records were reviewed and coded by a nosologist with expertise in E coding for a stratified random sample of 1000 probable work-related (PWR) and 250 probable non-work-related (PNWR) cases. Cause of injury E codes were present for 98% of reviewed cases and accurate for 65% of PWR cases and 57% of PNWR cases. Place of occurrence E codes were present in less than 30% of cases. Broad cause of injury categories were accurate for about 85% of cases. Non-specific categories (not elsewhere classified, not specified) accounted for 34% of broad category misclassifications. Among specified causes, machinery injuries were misclassified most often (39/60, 65%), predominantly as cut/pierce or struck by/against. E codes reliably identify the broad mechanism of injury, but inaccuracies and incompleteness suggest areas for training of hospital admissions staff, providers, and coders.

Case-by-case assessment of adult-onset asthma attributable to occupational exposures among members of a health maintenance organization

OBJECTIVE

In a general population of employed persons with health insurance, what proportion of adult-onset asthma is caused by occupational exposures?

METHOD

We conducted a 2-year prospective study to identify adult-onset asthma among health maintenance organization (HMO) members. Telephone interviews regarding occupational exposures, symptoms, medication use, and triggers were used to assess likelihood of work-related asthma for each case. Weighted estimating equations were used to adjust the proportion of asthma attributable to workplace exposures for factors associated with interview participation.

RESULTS

Overall, 29% (95% confidence interval, 25-34%) of adult-onset asthma was attributable to workplace exposures; 26% (21-30%) and 22% (18-27%) of cases had asthma attributable to occupational irritant and sensitizer exposures, respectively.

CONCLUSIONS

Occupational exposures, including irritants, are important causes of adult-onset asthma.

Characteristics of work related asthma: results from a population based survey

OBJECTIVES

Many risk factors for asthma have been investigated, one of which is the workplace. Work related asthma is a frequently reported occupational respiratory disease yet the characteristics which distinguish it from non-work related asthma are not well understood. The purpose of this study was to examine differences between work related and non-work related asthma with respect to healthcare use and asthma control characteristics.

METHODS

Data from the Massachusetts Behavioral Risk Factor Surveillance System for 2001 and 2002 were used for this analysis. Work related status of asthma was determined by self-report of ever having been told by a physician that asthma was work related. Healthcare measures evaluated were emergency room visits and physician visits for worsening asthma and for routine care. Characteristics of asthma control evaluated were frequency of asthma symptoms, asthma attacks, difficulty sleeping, and asthma medication usage in the last 30 days and limited activity in the past 12 months.

RESULTS

The prevalence of lifetime and current asthma in Massachusetts were 13.0% and 9.2%, respectively. Approximately 6.0% (95% CI 4.8 to 7.3) of lifetime and 6.2% (95% CI 4.7 to 7.8) of current asthma cases were work related. In the past 12 months, individuals with work related current asthma were 4.8 times (95% CI 2.0 to 11.6) as likely to report having an asthma attack, 4.8 times (95% CI 1.8 to 13.1) as likely to visit the emergency room at least once, and 2.5 times (95% CI 1.1 to 6.0) as likely to visit the doctor at least once for worsening asthma compared to individuals with non-work related asthma.

CONCLUSIONS

Work related asthma is associated with increased frequency of asthma attacks and use of healthcare services. A better understanding of factors that contribute to differences in healthcare use and asthma control is needed to improve prevention and control strategies for individuals suffering from the disease.

A longitudinal study of adult-onset asthma incidence among HMO members

BACKGROUND

HMO databases offer an opportunity for community based epidemiologic studies of asthma incidence, etiology and treatment. The incidence of asthma in HMO populations and the utility of HMO data, including use of computerized algorithms and manual review of medical charts for determining etiologic factors has not been fully explored.

METHODS

We identified adult-onset asthma, using computerized record searches in a New England HMO. Monthly, our software applied exclusion and inclusion criteria to identify an "at-risk" population and "potential cases". Electronic and paper medical records from the past year were then reviewed for each potential case. Persons with other respiratory diseases or insignificant treatment for asthma were excluded. Confirmed adult-onset asthma (AOA) cases were defined as those potential cases with either new-onset asthma or reactivated mild intermittent asthma that had been quiescent for at least one year. We validated the methods by reviewing charts of selected subjects rejected by the algorithm.

RESULTS

The algorithm was 93 to 99.3% sensitive and 99.6% specific. Sixty-three percent (n = 469) of potential cases were confirmed as AOA. Two thirds of confirmed cases were women with an average age of 34.8 (SD 11.8), and 45% had no evidence of previous asthma diagnosis. The annualized monthly rate of AOA ranged from 4.1 to 11.4 per 1000 at-risk members. Physicians most commonly attribute asthma to infection (59%) and allergy (14%). New-onset cases were more likely attributed to infection, while reactivated cases were more associated with allergies. Medical charts included a discussion of work exposures in relation to asthma in only 32 (7%) cases. Twenty-three of these (72%) indicated there was an association between asthma and workplace exposures for an overall rate of work-related asthma of 4.9%.

CONCLUSION

Computerized HMO records can be successfully used to identify AOA. Manual review of these records is important to confirm case status and is useful in evaluation of provider consideration of etiologies. We demonstrated that clinicians attribute most AOA to infection and tend to ignore the contribution of environmental and occupational exposures.

An examination of the spatial working memory deficit following neurotoxic medial dorsal thalamic lesions in rats

The present study examined the performance of rats with neurotoxic lesions centred in the thalamic nucleus medialis dorsalis on standard and modified versions of the eight arm radial maze test. In Experiment 1, the thalamic lesions produced a borderline deficit in acquisition of the standard task, but subsequently had no effect when a delay was interposed after the first four arms had been entered. The same lesions had no effect on T-maze alternation, but they did impair radial-arm maze performance when intramaze and extramaze cues were set against each other. In Experiment 2, lesions of the dorsomedial thalamus impaired acquisition of the standard radial-arm maze task, but combining the results from Experiments 1 and 2 showed that this acquisition deficit was confined to those animals in which bilateral damage extended into the adjacent anterior thalamic nuclei. In addition, lesions of the dorsomedial thalamus disrupted radial-arm maze performance when the task was modified to compare working memory and reference memory and increased activity and exploration. These changes were not associated with anterior thalamic damage. Finally, the thalamic lesions did not affect performance on a test of spontaneous object recognition. It is concluded that lesions of medialis dorsalis do not disrupt spatial memory but do affect other processes that can interact with task performance. These include a failure of extramaze cues to overshadow intramaze cues, a change in activity and exploration levels and deficits in with-holding spatial responses.

Neurotoxic lesions of the dorsomedial thalamus impair the acquisition but not the performance of delayed matching to place by rats: a deficit in shifting response rules

This study examined the acquisition of a T-maze matching to place task by rats with neurotoxic lesions of the thalamic nucleus medialis dorsalis. This test of spatial working memory also entails learning a task rule that is contrary to the animals' innate preference. The rats next performed the same matching task over different retention delays. Finally, they were trained on a reversal of the task rule, i.e., to nonmatch to place. Although the lesions produced a clear acquisition impairment on the matching task, there was no evidence of a loss of working memory. A series of control tasks found no appreciable effect on a conditioned cue preference task or on open field activity. The pattern of results shows that medialis dorsalis lesions lead to a selective increase in perseverative behavior that can retard task acquisition. This perseverative deficit closely resembles that observed after prefrontal damage in rats, strongly indicating dysfunction in a common system.

Evolution of post and core systems

Post and core systems have evolved dramatically over the past few years. Some procedures based on the use of resin-composite systems seem destined for failure in the long term. New glass ionomer based systems, employing resin hybrid materials should give rise to fewer complications and prove simpler to use. Nevertheless, intelligent case selection and the application of sound basic design principles are required to make the best use of any system.

The effects of selective lesions within the anterior thalamic nuclei on spatial memory in the rat

Groups of rats received cytotoxic lesions centred in either the anterior thalamic nucleus (AM), the anterior ventral and anterior dorsal thalamic nuclei (AV/AD), or all three nuclei combined (ANT.T). These lesions were made by injecting N-methyl-D-aspartate acid (NMDA). These rats, and a group of surgical controls (SHAM), were trained on a rewarded forced-alternation task in a T-maze. While the selective AM and AV/AD lesions produced an initial acquisition impairment, only the animals with combined lesions (ANT.T) showed a persistent deficit throughout the 16 acquisition sessions. Subsequent testing with a cross-maze confirmed that the SHAM, AV/AD, and AM groups were able to use allocentric cues, while the ANT.T group were impaired. In contrast none of the three anterior groups were impaired on a subsequent egocentric discrimination and reversal task run in the same apparatus. A final test using the eight arm radial-maze, revealed marked deficits in the ANT.T group as well as milder deficits in the AV/AD group. The results from these experiments help to confirm the importance of the anterior thalamic nuclei for allocentric tasks, but suggest that no region is pre-eminently important. The findings also help to account for other studies which have reported that anterior thalamic lesions have seemingly mild effects on tests of spatial memory.

A comparison of the effects of anterior thalamic, mamillary body and fornix lesions on reinforced spatial alternation

The effects of cytotoxic lesions in either the anterior thalamic nuclei or the mamillary bodies were compared with those of fornix lesions on a test of spatial working memory. All three lesions impaired acquisition of a forced alternation task in a T-maze, but the disruptive effects of the mamillary body lesions were significantly less than those following either fornix or anterior thalamic damage. When the alternation task was changed, so as to increase proactive interference, the impairment associated with mamillary body damage became more evident and was now equal in severity to that in the animals with anterior thalamic lesions. The fornix lesion group were the most impaired. In contrast, all three groups performed normally on a test of object recognition. The results add weight to the view that hippocampal--anterior thalamic connections are critical for normal spatial memory and that the relative contribution of the mamillary bodies is task dependent.

The effects of lesions to the fornix and dorsomedial thalamus on concurrent discrimination learning by rats

Rats with lesions in either the fornix or the thalamic nucleus medialis dorsalis were unimpaired on the acquisition of two object discrimination tasks. The same animals were then tested on a concurrent learning task in which various object discriminations were presented at different rates during the same session. This arrangement was primarily designed to minimise any response bias effects. Animals were able to acquire the various concurrent tasks, even when only one trial per day was given for a particular discrimination. It was found that fornix lesions had little or no effect and only produced a mild impairment when the rate of stimulus presentation resembled that used in typical concurrent tasks. Lesions of medialis dorsalis produced a more general, but again mild, deficit. In a final task, the animals were trained to discriminate between two stimuli composed of common elements arranged in different spatial combinations. Fornix lesions impaired acquisition of this spatial configural discrimination, while lesions of medialis dorsalis had a variable effect. The results indicate that fornix lesions can spare concurrent discrimination learning, and that any deficits may be related to interference effects associated with common elements in the stimuli. Lesions in medialis dorsalis appear to affect the initial learning of reward-based performance rules.

Removal of the hippocampus and transection of the fornix produce comparable deficits on delayed non-matching to position by rats

Rats with radiofrequency lesions of the fimbria/fornix or with extensive aspiration lesions of the hippocampal region (the hippocampus proper, dentate gyrus, and subicular complex) were tested on their performance of a delayed non-matching to position task which had been learnt before surgery. On a given trial, one of two sample levers was presented in a random manner. Following a response on this lever and a subsequent delay, both levers were presented and reward was now contingent on a response on the lever that was not used as the sample. Both lesions produced equivalent performance deficits on this test of spatial working memory, the pattern of these deficits being consistent with a mnemonic impairment. The lack of difference between these two groups on a variety of performance measures indicates that hippocampal connections passing through the fornix are not only necessary for this test, but that non-fornical hippocampal connections appear unable on their own to maintain accurate responding.

Ovarian follicular response of mares to GnRH agonist (leuprolide acetate) treatment after pituitary suppression

Follicular growth and ovulation were monitored in 18 horse mares during a control cycle and during a cycle in which the mares received a GnRH agonist, leuprolide acetate (LA; 200 or 400 mug), twice daily until ovulation. Prior to both of these cycles, follicular growth was suppressed using a 10-day estrogen-progesterone treatment regimen, with prostaglandin F-2alpha (10 mg) administered on Day 10. Four of the mares treated with LA remained anovulatory for at least 3 weeks after the end of treatment and were excluded from statistical analysis. The dosage of LA did not affect response. Treatment with LA significantly (P=0.0375) increased the percentage of large follicles per ovulation (i.e., follicles greater than 30 mm in diameter on the day on which the largest follicle reached 35 mm) and also increased (P=0.0539) the diameter of the second largest follicle. However LA did not significantly alter the number of ovulations. Mean daily concentrations of luteinizing hormone (LH) were not significantly different during treatment and control cycles. The LH in blood samples collected repeatedly on Day 19 after the start of estrogen-progesterone treatment did not show a difference in frequency or amplitude of pulses between treatment and control cycles. Mares were artificially inseminated during estrus and the embryos were recovered. Fewer embryos were recovered per ovulation from mares after treatment with LA (26%) than during the control cycle (64%). Results indicate that treatment with LA either suppressed follicular activity or induced multiple follicular growth.

Medial dorsal thalamic lesions and working memory in the rat

Pigmented rats of the DA strain with either radiofrequency or ibotenic acid lesions of the thalamic nucleus medialis dorsalis were postoperatively given nonspatial and spatial tests of working memory. In the nonspatial task, delayed nonmatching-to-sample, rats with both types of thalamic lesions showed acquisition impairments. The subgroup of rats with nucleus medialis dorsalis lesions that were able to reach the acquisition criterion did, however, perform normally when the retention interval was extended to 60 s. In the spatial task, delayed forced-alternation, rats were tested with differing retention intervals and with both spaced and massed trials. Damage to nucleus medialis dorsalis had no effect on acquisition or on spaced trials, but a slight deficit was found in the animals with radiofrequency lesions under the massed trial condition. Much clearer deficits were, however, present in those animals in which the lesion extended appreciably into the anterior thalamic nuclei. The findings indicate that while cellular damage to nucleus medialis dorsalis may disrupt learning, some impairments in tests of spatial working memory attributed to this nucleus may reflect damage to the adjacent anterior thalamic nuclei.

The effects of mammillary body and combined amygdalar-fornix lesions on tests of delayed non-matching-to-sample in the rat

A series of experiments compared the effects of mammillary body lesions with those of combined damage to the amygdala and fornix on 2 tests of working memory, both of which used the delayed non-matching-to-sample rule. This comparison was based on evidence of the involvement of these regions in anterograde amnesic syndromes. The mammillary body lesions had no effect on the acquisition or subsequent performance of a non-spatial recognition task and had only a mild effect on the acquisition of a spatial forced-alternation task. Although the animals with combined amygdalar plus fornix lesions were able to master the non-spatial recognition task they were impaired when the levels of proactive interference were increased. The same animals were also severely impaired on the forced-choice alternation task. The overall pattern of results is seen as mirroring those found in primates and points to an underlying similarity in the mnemonic roles of these limbic regions.

Ultrasound as an aid to diagnosis of granulosa cell tumour in the mare

The ultrasonic appearance of seven cases of granulosa cell tumour is described, and compared with an ovarian haematoma and an ovarian serous cystadenoma. The granulosa cell tumours varied from being uniformly dense to having one or several large fluid filled cysts. Some tumours resembled the haematoma or cystadenoma and also, in some aspects, normal ovarian structures such as corpora haemorrhagica or follicles in early pregnancy. There was no typical ultrasonographic appearance of the granulosa cell tumours which enabled definitive diagnosis. However, ultrasound may be a diagnostic aid when used in conjunction with the history and findings on rectal palpation.

Cervical hyperplasia with prolapse in a mare

Cervical hyperplasia with prolapse through the vulvar lips was documented in a mare. Postmortem examination indicated that the mass originated from the cervical wall. The surface of the prolapsed mass had histologic features of normal cervix. Cervical hyperplasia can be considered in a list of differential diagnoses in cases of prolapse of the internal genitalia in mares.

The future of esthetic dentistry

The materials and techniques of esthetic dentistry are provoking reconsideration of the basic principles of operative dentistry. Cavity preparations can be minimized, demands on retention are altered, and prevention can be practiced. Problems remain, particularly in bonding and sealing to dentin. The newer materials have yet to prove themselves in terms of durability, especially in regard to fracture and wear.

The effects of hippocampal lesions upon spatial and non-spatial tests of working memory

A series of experiments examined the proposal that the primary effect of hippocampal damage in rats is to disrupt working memory. Although extensive hippocampal lesions produced a severe impairment in forced-choice alternation--a test of spatial working memory--the same lesions did not impair the acquisition of a non-spatial test of working memory--delayed non-matching-to-sample. This test of object recognition required the rats to select that arm in a Y-maze which contained unfamiliar stimuli. Rats with hippocampal lesions were able to learn and perform this task at normal rates, even with retention delays of as long as 60 s. Two additional experiments helped confirm that the animals had indeed learnt a non-spatial test of working memory. The final experiment examined whether hippocampal lesions resulted in an increased sensitivity to proactive interference. It was found that repetition of test stimuli within a session, which increased interference, did attenuate recognition performance but there was no evidence that the animals with hippocampal lesions were differentially affected.

Influence of airway and airspace sizes on particle deposition in excised donkey lungs

Tests of aerosol deposition with breath holding and of lung function were performed on the excised lungs of three donkeys following regional in vivo radioaerosol deposition tests. Corrosion casts were made of the lungs to determine the dimensions of the tracheobronchial (TB) tree, and histological sections were taken to determine average alveolar airspace size. Static lung function tests, i.e., static compliance and specific compliance (Cstat and Cspec), agreed well with the predicted and reported in vivo values, as did the slope of Phase III from the single breath nitrogen washout (SBNW). Dynamic tests, i.e., dynamic compliance (Cdyn) and pulmonary resistance (Rpulm), displayed larger inter- and intra-subject variation, and showed poor agreement with reported in vivo values. Breathholding tests using 0.55 micron diameter aerosol indicated a mean respiratory airspace dimension of 0.16 mm, while the mean alveolar diameter from the lung sections was 0.19 mm. Breathholding tests with 1.18 micron aerosol indicated a mean small airway size of 0.65 mm, corresponding to the sizes of small airways on the corrosion casts. The donkeys have larger central airways but smaller peripheral airways than humans, and greater tracheobronchial deposition efficiency for 5 micron diameter particles. Tracheobronchial deposition in donkeys appears to be concentrated more distally than in humans, and may be related to the monopodal airway branching pattern in the former.

Safety aspects of mandibular lingual surgery

Mandibular lingual surgery is commonly used in periodontal practice. There are inherent risks in such surgery which are illustrated by a case report described here. This was a case in which an emergency tracheotomy was needed after a minor procedure which involved lingual tissues. The potential problems of any form of lingual surgery are discussed. Various other surgical procedures in this region are examined in order to establish some surgical principles which may be of use to periodontists.