Complication rates following reverse and anatomic shoulder replacement in treatment of glenohumeral arthritis: a 10-year Medicare review study.

BACKGROUND: We sought to compare the complication rates after anatomic total shoulder arthroplasty (aTSA) and reverse shoulder arthroplasty (RSA) for primary glenohumeral arthritis in a Medicare population. METHODS: Patients who underwent a shoulder arthroplasty were identified from the 5% subset of Medicare parts A/B between 2009 and 2019. Patients with less than 1-year follow-up were excluded. A total of 8846 patients with a diagnosis of glenohumeral arthritis were then subdivided into those who received aTSA (5935 patients) and RSA (2911 patients). A multivariate Cox regression analysis was then performed comparing complication rates at 3 months, 6 months, 1 year, 2 years, and 5 years. RESULTS: Statistically significant increased rates of instability (hazard ratio [HR] = 1.46), fracture of the scapula (HR = 7.76), infections (HR = 1.45), early revision (HR = 1.79), and all complications (HR = 1.32) were seen in the RSA group. There was no significant difference in revision rate at 5 years between the 2 groups. There was no difference in patient characteristics or comorbid conditions (smoking status, diabetes, Charlson score, etc.) or hospital characteristics (location, teaching status, public vs. private, etc.) between the 2 groups. CONCLUSION: An increased rate of early complications was observed with the use of RSA compared with aTSA for the treatment of primary glenohumeral arthritis, including instability, scapula fracture, infection, and all cause complication. No difference in revision rate between RSA and aTSA at 5 years was observed.

Environmental chamber studies of eye and respiratory irritation from use of a peracetic acid-based hospital surface disinfectant.

Objective: To characterize personal exposures and measures of eye and respiratory tract irritation in controlled environmental chamber studies of 44 healthy adult volunteers simulating upper-bound use of peracetic acid (PAA)-based surface disinfectant for terminal cleaning of hospital patient rooms. Design: Experimental, within-subject, double-blinded cross-over design. Methods: Objective and subjective exposure effects were assessed for PAA and its components: acetic acid (AA) and hydrogen peroxide (HP). Deionized water was included as a control. Breathing-zone concentrations of PAA, AA, and HP were assessed for 8 female multiday volunteers (5 consecutive days) and 36 single-day volunteers (32 females and 4 males). Wetted cloths were used to wipe high-touch surfaces for 20 minutes per trial. Also, 15 objective measures of tissue injury or inflammation and 4 subjective odor or irritation scores were assessed. Results: Disinfectant trials showed 95th percentile breathing zone concentrations of 101 ppb PAA, 500 ppb AA, and 667 ppb HP. None of the volunteers observed over 75 test days exhibited significant increases in IgE or objective measures of eye and respiratory tract inflammation. Subjective ratings for disinfectant and AA-only trials showed similar increases for odor intensity and nose irritation, with lower ratings for eye and throat irritation. Females were 2.5-fold more likely than males to assign moderate + irritation ratings. Conclusions: Simulated upper-bound hospital use of PAA-based disinfectant led to no significant increases in objective markers of tissue injury, inflammation, or allergic sensitization, and no frank signs of eye or respiratory tract irritation.

Incidence of Instability Following Primary Total Hip Arthroplasty Continues to Decline in the Medicare Population.

BACKGROUND: Instability has been the primary cause of failure following primary total hip arthroplasty (THA) leading to revision hip surgery. The purpose of this study was to determine if instability rates have further declined following advances in primary THA, including dual mobility articulations, direct anterior approaches, advanced technologies, and improved knowledge of the hip-spine relationships. METHODS: Using the 5% Medicare Part B claims data from 1999 to 2019, we identified 81,573 patients who underwent primary THA for osteoarthritis. Patients who experienced instability at 3 months, 6 months, 1 year, and 2 years were identified. Multivariate cox regression analyses evaluated the effect of patient and procedure characteristics on the risk of instability. RESULTS: Instability at 1 year following primary THA declined from approximately 4% in 2000 to 2.3% in 2010 and 1.6% in 2018. The leading cause of revision surgery was infection (18.6%), followed by periprosthetic fracture (14%), mechanical loosening (11.5%), and instability (9.4%). High-risk groups for instability continue to include increased age, higher Charlson index, obesity, lumbar spine pathology, and neurocognitive disorders. CONCLUSION: Instability is no longer the leading etiology of failure following primary THA with a decline of approximately 40% over the past decade. Infection, periprosthetic fracture, mechanical loosening, and then instability are now the leading causes of failure. Multiple factors may play a role in the decline of instability, including increased use of dual mobility articulations, direct anterior approaches, improved knowledge of the hip-spine relationships, and use of advanced technologies.

Manipulation Following Primary Total Knee Arthroplasty is Associated With Increased Rates of Infection and Revision.

BACKGROUND: Stiffness following total knee arthroplasty (TKA) is a disabling complication and manipulation under anesthesia (MUA) is often performed as an early intervention. Few studies have focused on the revision risk, infection risk, demographics, and clinical outcomes in Medicare patients undergoing MUA following primary TKA. METHODS: We reviewed 142,440 patients who had primary TKA from a national database and identified 3,652 patients (2.6%) who underwent MUA. Patient demographics and comorbid conditions were evaluated to identify risk factors. Incidence of revision and periprosthetic joint infection (PJI) at 1-, 2-, and 5-year time points in a cohort of MUA patients was compared to patients who did not undergo MUA. Multivariate Cox regressions were used for statistical analyses. RESULTS: The incidence of MUA was higher in Black versus White individuals (4.1 versus 2.5%, P < .001). Revision risk was significantly greater in the MUA group at 1-, 2-, and 5-year time points with a hazard ratio (HR) of, 3.81, 3.90, and 3.22 respectively, P < .001. One- and 2-year revision risk was significantly greater when MUA occurred at 6 to 12 months post-TKA when compared to <3 months, P < .05. Risk of PJI was significantly greater in the MUA group with a HR of 2.2, 2.2, and 2.1 at 1, 2, and 5 years, respectively P < .001. CONCLUSION: The incidence of MUA was 2.6%. There was an increased incidence of revision surgery and PJI in patients undergoing MUA. Patients at increased risk for stiffness following TKA should be closely monitored and treated with early intervention to minimize risk of poor outcomes.

Robotic-Arm Assisted Total Knee Arthroplasty: Cost Savings Demonstrated at One Year.

Purpose: Robotic-arm assisted total knee arthroplasty (RATKA) has the potential to enhance radiographic, clinical, and patient-reported outcomes. The purpose of this study was to compare resource utilization, episode-of-care (EOC) costs, readmissions, and complications of robotic-arm assisted total knee arthroplasty (RATKA) and manual TKA (MTKA). Methods: TKA procedures were identified from a private payer claims database. RATKA procedures required both a robotic arm-assisted procedure code and a 60-day pre-operative computed tomography scan. Propensity score matching (1:5 RATKA to MTKA) was performed, based on various patient characteristics and comorbidities. After matching, 4452 patients (742 RATKA and 3710 MTKA) were analyzed for 90-day and one-year EOC costs, index TKA costs, lengths of stay (LOS), discharge statuses, rehabilitation utilizations, as well as 90-day and one-year readmissions- and knee-related complications. Results: RATKA patients had shorter LOS (mean 1.56 versus 1.91 days; p < 0.001), lower index costs by $1762 ($32,747 versus $34,509; p = 0.003), and higher discharges to home rates (51.8 versus 47.8%; p = 0.049) than MTKA patients. RATKA patients had less 90-day (68.5 versus 72.0%; p = 0.048) and one-year (70.8 versus 75.0%; p = 0.016) home health utilizations. The RATKA cohort had lower 90-day ($39,260 versus $41,458; p = 0.001) and one-year ($51,462 versus $54,171; p = 0.011) EOC costs. No significant differences in readmission and overall complication rates were observed (p > 0.05). Conclusion: RATKA was associated with lower index costs and EOC costs at both 90 days and one year. These patients had shorter LOS, were discharged home more frequently, and used less home health services. Cost savings were demonstrated for RATKA beyond the 90-day period with an increase in savings between 90-day and one-year time points. These data may be of importance to payers and providers interested in the longer-term value of RATKA.

Monitored and Modeled Ambient Air Concentrations of Ethylene Oxide: Contextualizing Health Risk for Potentially Exposed Populations in Georgia.

Recent studies have monitored and modeled long-term ambient air concentrations of ethylene oxide (EO) around emitting facilities in Georgia with the intent of informing risk management of potentially exposed nearby residential populations. Providing health context for these data is challenging because the U.S. Environmental Protection Agency's risk-specific concentrations lack practical utility in distinguishing a health significant increase in exposure. This study analyzes EO data for eight emitting facilities, using a previously published alternative exposure metric, the total equivalent concentration, which is based on U.S. Centers for Disease Control biomarker data for the non-smoking U.S. POPULATION: Mean concentrations for monitoring sites were compared to mean background concentrations to assess whether emissions contribute significantly to environmental concentrations. To assess the health significance of potential exposure at nearby residential locations, the 50th percentile concentration was added to the 50th percentile endogenous equivalent concentration and compared to the total equivalent concentration distribution for the non-smoking U.S. POPULATION: The findings demonstrate that impacts from nearby emission sources are small compared to mean background concentrations at nearby locations, and the total equivalent concentrations for exposed populations are generally indistinguishable from that of the 50th percentile for the non-smoking U.S.

Essential concepts for interpreting the dose-response of low-level arsenic exposure in epidemiological studies.

Scientifically robust selections of epidemiological studies and assessments of the dose-response of inorganic arsenic in the low-dose range must consider key issues specific to arsenic in order to reduce risk of bias. The abundance of toxicological, mechanistic, and epidemiological evidence on arsenic enables a nuanced assessment of risk of bias in epidemiological studies of low-level arsenic, as opposed to a generic evaluation based only on standard principles. Important concepts in this context include 1) arsenic metabolism and mode of action for toxicity and carcinogenicity; 2) effects of confounding factors such as diet, health status including nutritional deficiencies, use of tobacco and other substances, and body composition; 3) strengths and limitations of various metrics for assessing relevant exposures consistent with the mode of action; and 4) the potential for bias in the positive direction for the observed dose-response relationship as exposure increases in the low-dose range. As an example, evaluation of a recent dose-response modeling using eight epidemiological studies of inorganic arsenic and bladder cancer demonstrated that the pooled risk estimate was markedly affected by the single study that was ranked as having a high risk of bias, based on the above factors. The other seven studies were also affected by these factors to varying, albeit lesser, degrees that can influence the apparent dose-response in the low-dose range (i.e., drinking water concentration of 65 µg/L or dose of approximately ≤1 µg/kg-day). These issues are relevant considerations for assessing health risks of oral exposures to inorganic arsenic in the U.S. population, and setting evidence-based regulatory limits to protect human health.

Ethylene Oxide Exposure in U.S. Populations Residing Near Sterilization and Other Industrial Facilities: Context Based on Endogenous and Total Equivalent Concentration Exposures.

Given ubiquitous human exposure to ethylene oxide (EO), regardless of occupation or geography, the current risk-specific concentrations (RSCs: 0.0001-0.01 ppb) from the U.S. Environmental Protection Agency (EPA) cancer risk assessment for EO are not useful metrics for managing EO exposures to the general U.S. population. The magnitude of the RSCs for EO are so low, relative to typical endogenous equivalent metabolic concentrations (1.1-5.5 ppb) that contribute ~93% of total exposure, that the RSCs provide little utility in identifying excess environmental exposures that might increase cancer risk. EO monitoring data collected in the vicinity of eight EO-emitting facilities and corresponding background locations were used to characterize potential excess exogenous concentrations. Both 50th and 90th percentile exogenous exposure concentrations were combined with the 50th percentile endogenous exposure concentration for the nonsmoking population, and then compared to percentiles of total equivalent concentration for this population. No potential total exposure concentration for these local populations exceeded the normal total equivalent concentration 95th percentile, indicating that excess facility-related exposures are unlikely to require additional management to protect public health.

What Are the Migration Patterns for U.S. Primary Total Joint Arthroplasty Patients?

BACKGROUND: Evaluation of total joint arthroplasty (TJA) patient-reported outcomes and survivorship requires that records of the index and potential revision arthroplasty procedure are reliably captured. Until the goal of the American Joint Replacement Registry (AJRR) of more-complete nationwide capture is reached, one must assume that patient migration from hospitals enrolled in the AJRR to nonAJRR hospitals occurs. Since such migration might result in loss to followup and erroneous conclusions on survivorship and other outcomes of interest, we sought to quantify the level of migration and identify factors that might be associated with migration in a specific AJRR population. QUESTIONS/PURPOSES: (1) What are the out-of-state and within-state migration patterns of U.S. Medicare TJA patients over time? (2) What patient demographic and institutional factors are associated with these patterns? METHODS: Hospital records of Medicare fee-for-service beneficiaries enrolled from January 1, 2004 to December 31, 2015, were queried to identify primary TJA procedures. Because of the nationwide nature of the Medicare program, low rates of loss to followup among Medicare beneficiaries, as well as long-established enrollment and claims processing procedures, this database is ideal for examining patient migration after TJA. We identified an initial cohort of 5.33 million TJA records from 2004 to 2016; after excluding patients younger than 65 years of age, those enrolled solely due to disability, those enrolled in a Medicare HMO, or residing outside the United States, the final analytical dataset consisted of 1.38 million THAs and 3.03 million TKAs. The rate of change in state or county of residence, based on Medicare annual enrollment data, was calculated as a function of patient demographic and institutional factors. A multivariate Cox model with competing risk adjustment was used to evaluate the association of patient demographic and institutional factors with risk of out-of-state or out-of-county (within-state) migration. RESULTS: One year after the primary arthroplasty, 0.61% (95% confidence interval [CI], 0.60-0.61; p < 0.001 for this and all comparisons in this Results section) of Medicare patients moved out of state and another 0.62% (95% CI, 0.60-0.63) moved to a different county within the same state. Five years after the primary arthroplasty, approximately 5.41% (95% CI, 5.39-5.44) of patients moved out of state and another 5.50% (95% CI, 5.46-5.54) Medicare patients moved to a different county within the same state. Among numerous factors of interest, women were more likely to migrate out of state compared with men (hazard ratios [HR], 1.06), whereas black patients were less likely (HR, 0.82). Patients in the Midwest were less likely to migrate compared with patients in the South (HR, 0.74). Patients aged 80 and older were more likely to migrate compared with 65- to 69-year-old patients (HR, 1.19). Patients with higher Charlson Comorbidity Index scores compared with 0 were more likely to migrate (index of 5+; HR, 1.19). CONCLUSIONS: Capturing detailed information on patients who migrate out of county or state, with associated changes in medical facility, requires a nationwide network of participating registry hospitals. At 5 years from primary arthroplasty, more than 10% of Medicare patients were found to migrate out of county or out of state, and the rate increases to 18% after 10 years. Since it must be assumed that younger patients might exhibit even higher migration levels, these findings may help inform public policy as a "best-case" estimate of loss to followup under the current AJRR capture area. Our study reinforces the need to continue aggressive hospital recruitment to the AJRR, while future research using an increasingly robust AJRR database may help establish the migration patterns of nonMedicare patients. LEVEL OF EVIDENCE: Level III, therapeutic study.

Multimodal Pain Management of Femoral Neck Fractures Treated With Hemiarthroplasty.

The purpose of this study was to evaluate a multimodal pain management program incorporating periarticular injections of liposomal bupivacaine after hemiarthroplasty treatment of femoral neck fractures. This retrospective study selected patients treated with periarticular injections of liposomal bupivacaine within the multimodal pain management program (LBUP) (n = 100) and a control group of patients treated without local infiltration (n = 78). Similar pain control was achieved between both groups from day 1 to day 4 postsurgery (min p = .392). Length of stay was significantly lower for LBUP patients (4.8 days vs. 5.7 days, p = .013), and LBUP patients were significantly more likely to be ambulatory at discharge (82% vs. 69%, p = .013). LBUP patients were also less likely to need the intensive care unit (4% vs. 14%, p = .027). The percentage of patients with at least one opioid-related adverse event was lower in the LBUP group (3% vs. 8%, p = .156) as was the 90-day mortality rate (2% vs. 8%, p = .069), but the differences were not statistically significant. (Journal of Surgical Orthopaedic Advances 28(1):58-62, 2019).

An Assessment of the Cox Proportional Hazards Regression Model for Epidemiologic Studies.

The basic assumptions of the Cox proportional hazards regression model are rarely questioned. This study addresses whether hazard ratio, i.e., relative risk (RR), estimates using the Cox model are biased when these assumptions are violated. We investigated also the dependence of RR estimates on temporal exposure characteristics, and how inadequate control for a strong, time-dependent confounder affects RRs for a modest, correlated risk factor. In a realistic cohort of 500,000 adults constructed using the National Cancer Institute Smoking History Generator, we used the Cox model with increasing control of smoking to examine the impact on RRs for smoking and a correlated covariate X. The smoking-associated RR was strongly modified by age. Pack-years of smoking did not sufficiently control for its effects; simultaneous control for effect modification by age and time-dependent cumulative exposure, exposure duration, and time since cessation improved model fit. Even then, residual confounding was evident in RR estimates for covariate X, for which spurious RRs ranged from 0.980 to 1.017 per unit increase. Use of the Cox model to control for a time-dependent strong risk factor yields unreliable RR estimates unless detailed, time-varying information is incorporated in analyses. Notwithstanding, residual confounding may bias estimated RRs for a modest risk factor.

An analysis of fatal and non-fatal injuries and injury severity factors among electric power industry workers.

BACKGROUND: The electric power industry represents a unique subset of the U.S. workforce. We aimed to evaluate the relationships between occupational category, nature of injury, and injury severity among electric power industry workers. METHODS: The Occupational Health and Safety Database (1995-2013) was used to calculate injury rates, assess patterns of injury severity, and identify at-risk occupations in this population. RESULTS: Over the surveillance period, a total of 63,193 injuries were reported. Overall, and severe injury rates were 3.20 and 0.52 per 100 employee-years, respectively. The fatal injury rate was 3.29 per 100,000 employee-years. Line workers experienced the highest risk for fatal injuries and second highest for non-fatal severe injuries, following meter readers. The most severe non-fatal injuries were hernia and rupture; multiple injuries; and CTD/RSI. Fatal injuries were most commonly associated with vehicle collisions and contact with electric current. CONCLUSIONS: Industry specific surveillance and interventions tailored to high-risk occupations are needed to further reduce severe injuries in this population. Am. J. Ind. Med. 59:948-958, 2016. © 2016 Wiley Periodicals, Inc.

Postoperative Pain After Primary Total Knee Arthroplasty: Comparison of Local Injection Analgesic Cocktails and the Role of Demographic and Surgical Factors.

BACKGROUND: It has been reported that pain-related outcomes after total knee arthroplasty (TKA) may vary with different analgesic techniques and with patient demographics. The purposes of this study were to compare local infiltration of regular bupivacaine (periarticular infiltration [PAI] group) vs liposomal bupivacaine (LBUP group) and to examine the effect of patient characteristics on postoperative pain after TKA. METHODS: The study sample included 665 consecutive TKA cases performed between December 2011 and August 2013. The primary outcome measures were the average visual analog scale (VAS) pain score and the percent of VAS pain scores that indicated no pain. Multivariable regression analyses investigated the effect of age, race, ethnicity, body mass index, gender, surgeon, and analgesic protocol on outcomes. For the analgesic groups, the "PAI" group received injections of a cocktail including bupivacaine, ketorolac, and morphine, whereas the "LBUP" group received injections of LBUP. RESULTS: The regression analysis demonstrated that postoperative pain was higher in females (P < .001) and younger patients (P < .001). Although overall average VAS pain scores were not significantly different, when specific postoperative days were evaluated, the LBUP group had lower pain scores from day 1 to 5 (P < .014). There were no differences in VAS scores based on patient body mass index (P = .250), race (P = .205), or ethnicity (P = .961) in this sample. CONCLUSION: This multivariate regression analysis study showed that in patients undergoing primary TKA, postoperative pain was lower in males, older patients, and those treated with LBUP. Awareness of these factors may assist in developing patient-specific multimodal postoperative pain and education protocols that reduce opioid reliance and related adverse events.

How Do Demographic, Surgical, Patient, and Cultural Factors Affect Pain Control After Unicompartmental Knee Arthroplasty? A Multivariable Regression Analysis.

BACKGROUND: Controlling pain after unicompartmental knee arthroplasty (UKA) is essential for improving patient satisfaction, minimizing complications, and early rehabilitation. There is little literature available evaluating the effect of both treatment and patient characteristics on in-hospital pain after UKA. The purpose of this study was to examine the effect of patient and treatment characteristics on in-hospital pain after UKA. This study also evaluated the role of analgesic cocktail (traditional periarticular injection cocktail "[PAI]" vs cocktail including liposomal bupivacaine "[LBUP]"). METHODS: The study sample included 442 consecutive UKA cases performed between December 2011 and August 2013. The primary outcome measures were the average Visual Analog Scale pain score and the percent of pain scores during hospitalization that were 0, that is, "no pain." Multivariable regression analyses were implemented to investigate associations between patient demographics and analgesic group with the outcomes. For the analgesic groups, the "PAI" group received injections of a cocktail including Marcaine, ketorolac, and morphine, the "LBUP" group received injections of LBUP. RESULTS: Postoperative pain was higher in females (P < .001) and younger patients (P = .002). The patient group treated with LBUP injection technique had similar overall average Visual Analog Scale pain scores to patients in the PAI group (P = .729); however, there was also a significant improvement in pain scores over time (as the study progressed) for patients in the LBUP group relative to the PAI group (P = .003), potentially indicating better outcomes with more experience with the injection technique. When compared individually by day, the LBUP group had lower pain scores from day 1 to 3 (P < .024). CONCLUSION: The results showed that in patients undergoing UKA, postoperative pain was lower in males, older patients, patients with lower body mass index, and those treated with LBUP over the study period. Understanding these associations is necessary to effectively manage pain and encourage earlier ambulation and physiotherapy after UKA.

Association between a shelter-neuter-return program and cat health at a large municipal animal shelter.

OBJECTIVE To determine effects of a shelter-neuter-return (SNR) program on cat admissions and health at a large municipal animal shelter in Northern California. DESIGN Retrospective cohort study. ANIMALS 117,383 cats for which data were recorded in the San Jose Animal Care Center database between January 1, 2006, and December 31, 2013. PROCEDURES Shelter records were analyzed for trends in cat demographic data, shelter intake and outcome types, and prevalence of upper respiratory infection (URI) over the 8-year period and before and after initiation of an SNR program on March 8, 2010. RESULTS Number of cats admitted to the shelter each year decreased significantly over 8 years; beginning in 2010, duration of stay decreased. Proportion of cats euthanized decreased from 66.6% (28,976/43,517) in the pre-SNR period to 34.9% (11,999/34,380) in the post-SNR period, whereas prevalence of URI increased from 5.5% to 6.8%, and median duration of shelter stay decreased from 6 to 5 days for cats < 4 months of age and from 8 to 6 days for older cats. With implementation of the SNR program and a new treatment policy for cats with URI, more cats received treatment with less medication, yielding cost savings. CONCLUSIONS AND CLINICAL RELEVANCE Initiation of the SNR program was associated with a decreased number of cats admitted to the shelter and a lower proportion euthanized. With increased resources to care for cats with URI and changes in the URI treatment protocol, fewer cats were euthanized for URI and more cats were treated at lower cost and with a briefer shelter stay.

Evaluation and quantitative microbial risk assessment of a unique antimicrobial agent for hospital surface treatment.

BACKGROUND: It is generally agreed that contaminated hospital surfaces play a role in the transmission of hospital-acquired infections (HAIs). The ability of an antimicrobial agent, engineered at Emory University, to reduce bacterial bioburden on hospital surfaces was examined. A quantitative microbial risk assessment was also conducted to quantify the potential reduction of human health risks associated with application of this antimicrobial product. METHODS: A 1-arm, prospective observational study was conducted. High-frequency contact surfaces within 18 hospital patient rooms were sampled in between patient use. Negative binomial regression with repeated measures was used to examine log CFU/100 cm(2) reductions in total, gram-negative, and Staphylococcus aureus microorganisms. Standard risk assessment methods were used. RESULTS: Multivariate regression demonstrated significant reductions in gram-negative (P < .0001) and S aureus (P = .009) bacteria with increasing patient turnover. No reduction was observed in total bacteria (P = .93). Infection risks were reduced by 4 and 3 logs for gram-positive and gram-negative bacteria, respectively. These risk reductions, along with HAI survey studies, suggest that application of this antimicrobial product could prevent as many as 5%-10% of HAIs. CONCLUSIONS: This study was the first evaluation of a distinctive antimicrobial agent for hospital surface treatment. The findings provide support for the utility of an antimicrobial product in potentially reducing HAI transmission from contaminated environment surfaces.

Diesel engine exhaust and lung cancer mortality: time-related factors in exposure and risk.

To develop a quantitative exposure-response relationship between concentrations and durations of inhaled diesel engine exhaust (DEE) and increases in lung cancer risks, we examined the role of temporal factors in modifying the estimated effects of exposure to DEE on lung cancer mortality and characterized risk by mine type in the Diesel Exhaust in Miners Study (DEMS) cohort, which followed 12,315 workers through December 1997. We analyzed the data using parametric functions based on concepts of multistage carcinogenesis to directly estimate the hazard functions associated with estimated exposure to a surrogate marker of DEE, respirable elemental carbon (REC). The REC-associated risk of lung cancer mortality in DEMS is driven by increased risk in only one of four mine types (limestone), with statistically significant heterogeneity by mine type and no significant exposure-response relationship after removal of the limestone mine workers. Temporal factors, such as duration of exposure, play an important role in determining the risk of lung cancer mortality following exposure to REC, and the relative risk declines after exposure to REC stops. There is evidence of effect modification of risk by attained age. The modifying impact of temporal factors and effect modification by age should be addressed in any quantitative risk assessment (QRA) of DEE. Until there is a better understanding of why the risk appears to be confined to a single mine type, data from DEMS cannot reliably be used for QRA.

Use of electronic medical records (EMR) for oncology outcomes research: assessing the comparability of EMR information to patient registry and health claims data.

UNLABELLED: Electronic medical records (EMRs) are used increasingly for research in clinical oncology, epidemiology, and comparative effectiveness research (CER). OBJECTIVE: To assess the utility of using EMR data in population-based cancer research by comparing a database of EMRs from community oncology clinics against Surveillance Epidemiology and End Results (SEER) cancer registry data and two claims databases (Medicare and commercial claims). STUDY DESIGN AND SETTING: DEMOGRAPHIC, CLINICAL, AND TREATMENT PATTERNS IN THE EMR, SEER, MEDICARE, AND COMMERCIAL CLAIMS DATA WERE COMPARED USING SIX TUMOR SITES: breast, lung/bronchus, head/neck, colorectal, prostate, and non-Hodgkin's lymphoma (NHL). We identified various challenges in data standardization and selection of appropriate statistical procedures. We describe the patient and clinic inclusion criteria, treatment definitions, and consideration of the administrative and clinical purposes of the EMR, registry, and claims data to address these challenges. RESULTS: Sex and 10-year age distributions of patient populations for each tumor site were generally similar across the data sets. We observed several differences in racial composition and treatment patterns, and modest differences in distribution of tumor site. CONCLUSION: Our experience with an oncology EMR database identified several factors that must be considered when using EMRs for research purposes or generalizing results to the US cancer population. These factors were related primarily to evaluation of treatment patterns, including evaluation of stage, geographic location, race, and specialization of the medical facilities. While many specialty EMRs may not provide the breadth of data on medical care, as found in comprehensive claims databases and EMR systems, they can provide detailed clinical data not found in claims that are extremely important in conducting epidemiologic and outcomes research.

Identification of an autoantibody panel to separate lung cancer from smokers and nonsmokers.

BACKGROUND: Sera from lung cancer patients contain autoantibodies that react with tumor associated antigens (TAAs) that reflect genetic over-expression, mutation, or other anomalies of cell cycle, growth, signaling, and metabolism pathways. METHODS: We performed immunoassays to detect autoantibodies to ten tumor associated antigens (TAAs) selected on the basis of previous studies showing that they had preferential specificity for certain cancers. Sera examined were from lung cancer patients (22); smokers with ground-glass opacities (GGOs) (46), benign solid nodules (55), or normal CTs (35); and normal non-smokers (36). Logistic regression models based on the antibody biomarker levels among the high risk and lung cancer groups were developed to identify the combinations of biomarkers that predict lung cancer in these cohorts. RESULTS: Statistically significant differences in the distributions of each of the biomarkers were identified among all five groups. Using Receiver Operating Characteristic (ROC) curves based on age, c-myc, Cyclin A, Cyclin B1, Cyclin D1, CDK2, and survivin, we obtained a sensitivity = 81% and specificity = 97% for the classification of cancer vs smokers(no nodules, solid nodules, or GGO) and correctly predicted 31/36 healthy controls as noncancer. CONCLUSION: A pattern of autoantibody reactivity to TAAs may distinguish patients with lung cancer versus smokers with normal CTs, stable solid nodules, ground glass opacities, or normal healthy never smokers.

Histologic features are important prognostic indicators in early stages lung adenocarcinomas.

This study attempts to evaluate the clinicopathologic features of mixed subtype adenocarcinomas and the prognostic implications of histopathology classifications. Surgical specimens from 141 patients with clinical stage I or II lung adenocarcinoma during the period 1992-2004 were included. These cases were classified into four groups defined by the extent of the bronchioloalveolar carcinoma component: group I: pure bronchioloalveolar carcinoma; group II: mixed subtype with predominant bronchioloalveolar carcinoma component and < or = 5 mm invasive component; group III: mixed subtype with bronchioloalveolar carcinoma component and > 5 mm invasive component; group IV: invasive carcinoma with no bronchioloalveolar carcinoma component. Descriptive statistics were used to examine the groups with respect to age, tumor size, lymph node metastasis, and Ki-67 and p53 expression levels. Death rate for the groups was obtained by patient's charts and from the National Death Index database. The population was similar in age, tumor size and lymph node metastasis. Immunohistochemical results showed that the mean Ki-67 labeling and the amount of p53 overexpression had the same trend of increasing mean values or positive results from groups I to IV. The reported proportion of deaths ranged from 0% for groups I and II, 20% in patients with predominant invasive component with bronchioloalveolar carcinoma (group III), and 18% in patients with invasive carcinomas and no bronchioloalveolar carcinoma component (group IV). The difference between the proportion of patients with reported deaths in the time period of this study in the combined greater than 5 mm+pure invasive groups (groups III, IV), and the < 5 mm + noninvasive groups (groups I, II) is statistically significant. These results suggest that histological features may be useful in defining categories of lung adenocarcinomas with differing survival and prognostic features. These results are helpful in defining a subcategory of 'minimally invasive adenocarcinoma', which has features similar to bronchioloalveolar carcinoma.