Identification of Hospital-Acquired Catheter-Associated Urinary Tract Infections From Medicare Claims: Sensitivity and Positive Predictive Value

Development and validation of models for detection of postoperative infections using structured electronic health records data and machine learning

BACKGROUND

Postoperative infections constitute more than half of all postoperative complications. Surveillance of these complications is primarily done through manual chart review, which is time consuming, expensive, and typically only covers 10% to 15% of all operations. Automated surveillance would permit the timely evaluation of and reporting of all operations.

METHODS

The goal of this study was to develop and validate parsimonious, interpretable models for conducting surveillance of postoperative infections using structured electronic health records data. This was a retrospective study using 30,639 unique operations from 5 major hospitals between 2013 and 2019. Structured electronic health records data were linked to postoperative outcomes data from the American College of Surgeons National Surgical Quality Improvement Program. Predictors from the electronic health records included diagnoses, procedures, and medications. Infectious complications included surgical site infection, urinary tract infection, sepsis, and pneumonia within 30 days of surgery. The knockoff filter, a penalized regression technique that controls type I error, was applied for variable selection. Models were validated in a chronological held-out dataset.

RESULTS

Seven percent of patients experienced at least one type of postoperative infection. Models selected contained between 4 and 8 variables and achieved >0.91 area under the receiver operating characteristic curve, >81% specificity, >87% sensitivity, >99% negative predictive value, and 10% to 15% positive predictive value in a held-out test dataset.

CONCLUSION

Surveillance and reporting of postoperative infection rates can be implemented for all operations with high accuracy using electronic health records data and simple linear regression models.

State and Government Administrative Databases: Medicare, National Inpatient Sample (NIS), and State Inpatient Databases (SID) Programs

The availability of large state and federally run administrative health-care databases provides potentially comprehensive population-wide information that can dramatically impact both medical and health-policy decision-making. Specific opportunities and important limitations exist with all administrative databases based on what information is collected and how reliably specific data elements are reported. Access to patient identifiable-level information can be critical for certain long-term outcome studies but can be difficult (although not impossible) due to patient privacy protections, while more easily available de-identified information can provide important insights that may be more than sufficient for some short-term operative or in-hospital outcome questions. The first section of this paper by Sarah K. Meier and Benjamin D. Pollock discusses Medicare and the different data files available to health-care researchers. They describe what is and is not generally available from even the most granular Medicare Standard Analytic Files, and provide an analysis of the strengths and weaknesses of Medicare administrative data as well as the resulting best and inappropriate uses of these data. In the second section, the Nationwide Inpatient Sample and complementary State Inpatient Database programs are reviewed by Steven M. Kurtz and Edmund Lau, with insights into the origins of these programs, the data elements that are recorded relating to the operative procedure and hospital stay, and examples of the types of studies that optimally utilize these data sources. They also detail the limitations of these databases and identify studies that they are not well-suited for, especially those involving linkage or longitudinal studies over time. Both sections provide useful guidance on the best uses and pitfalls related to these important large representative national administrative data sources.

Systematic Undercoding of Diagnostic Procedures in National Inpatient Sample (NIS): A Threat to Validity Due to Surveillance Bias

BACKGROUND AND OBJECTIVES

Health services research often relies on readily available data, originally collected for administrative purposes and used for public reporting and pay-for-performance initiatives. We examined the prevalence of underreporting of diagnostic procedures for acute myocardial infarction (AMI), deep venous thrombosis (DVT), and pulmonary embolism (PE), used for public reporting and pay-for-performance initiatives.

METHOD

We retrospectively identified procedures for AMI, DVT, and PE in the National Inpatient Sample (NIS) database between 2012 and 2016. From January 1, 2012, through September 30, 2015, the NIS used the International Classification of Diseases, Ninth Revision (ICD-9) coding scheme. From October 1, 2015, through December 31, 2016, the NIS used the International Classification of Diseases, Tenth Revision (ICD-10) coding scheme. We grouped the data by ICD code definitions (ICD-9 or ICD-10) to reflect these code changes and to prevent any confounding or misclassification. In addition, we used survey weighting to examine the utilization of venous duplex ultrasound scan for DVT, electrocardiogram (ECG) for AMI, and chest computed tomography (CT) scan, pulmonary angiography, echocardiography, and nuclear medicine ventilation/perfusion () scan for PE.

RESULTS

In the ICD-9 period, by primary diagnosis, only 0.26% (n = 5930) of patients with reported AMI had an ECG. Just 2.13% (n = 7455) of patients with reported DVT had a peripheral vascular ultrasound scan. For patients with PE diagnosis, 1.92% (n = 12 885) had pulmonary angiography, 3.92% (n = 26 325) had CT scan, 5.31% (n = 35 645) had cardiac ultrasound scan, and 0.45% (n = 3025) had scan. In the ICD-10 period, by primary diagnosis, 0.04% (n = 345) of reported AMI events had an ECG and 0.91% (n = 920) of DVT events had a peripheral vascular ultrasound scan. For patients with PE diagnosis, 2.08% (n = 4805) had pulmonary angiography, 0.63% (n = 1460) had CT scan, 1.68% (n = 3890) had cardiac ultrasound scan, and 0.06% (n = 140) had scan. Small proportions of diagnostic procedures were observed for any diagnoses of AMI, DVT, or PE.

CONCLUSIONS

Our findings question the validity of using NIS and other administrative databases for health services and outcomes research that rely on certain diagnostic procedures. Unfortunately, the NIS does not provide granular data that can control for differences in diagnostic procedure use, which can lead to surveillance bias. Researchers and policy makers must understand and acknowledge the limitations inherent in these databases, when used for pay-for-performance initiatives and hospital benchmarking.

Uncontrolled diabetes mellitus increases risk of infection in patients with advanced cirrhosis

BACKGROUND

Diabetes mellitus (DM) is common in patients with cirrhosis and is associated with increased risk of infection.

AIM

To analyze the impact of uncontrolled DM on infection and mortality among inpatients with advanced cirrhosis.

METHODS

This study utilized the Nationwide Inpatient Sample from 1998 to 2014. We defined advanced cirrhosis using a validated ICD-9-CM algorithm requiring a diagnosis of cirrhosis and clinically significant portal hypertension or decompensation. The primary outcome was bacterial infection. Secondary outcomes included inpatient mortality stratified by elderly age (age≥70). Multivariable logistic regression analyzed outcomes.

RESULTS

906,559 (29.2%) patients had DM and 109,694 (12.1%) were uncontrolled. Patients who had uncontrolled DM were younger, had less ascites, but more encephalopathy. Bacterial infection prevalence was more common in uncontrolled DM (34.2% vs. 28.4%, OR 1.33, 95% CI 1.29-1.37, p<0.001). Although uncontrolled DM was not associated with mortality, when stratified by age, elderly patients with uncontrolled DM had a significantly higher risk of inpatient mortality (OR 1.62, 95% CI 1.46-1.81).

CONCLUSIONS

Uncontrolled DM is associated with increased risk of infection, and when combined with elderly age is associated with increased risk of inpatient mortality. Glycemic control is a modifiable target to improve morbidity and mortality in patients with advanced cirrhosis.

Hospital-Acquired Condition Reduction Program Is Not Associated With Additional Patient Safety Improvement

In 2013 the Centers for Medicare and Medicaid Services announced that it would begin levying penalties against hospitals with the highest rates of hospital-acquired conditions through the Hospital-Acquired Condition Reduction Program. Whether the program has been successful in improving patient safety has not been independently evaluated. We used clinical registry data on rates of hospital-acquired conditions in 2010-18 from a large surgical collaborative in Michigan to estimate the impact of the policy. While rates of all such conditions declined from 133.4 per 1,000 discharges in the pre-program period to 122.2 in the post-program period, greater improvements were observed for nontargeted measures. We conclude that the program did not improve patient safety in Michigan beyond existing trends. These findings raise questions about whether the program will lead to improvements in patient safety as intended.

Identification of postoperative complications using electronic health record data and machine learning

BACKGROUND

Using the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) complication status of patients who underwent an operation at the University of Colorado Hospital, we developed a machine learning algorithm for identifying patients with one or more complications using data from the electronic health record (EHR).

METHODS

We used an elastic-net model to estimate regression coefficients and carry out variable selection. International classification of disease codes (ICD-9), common procedural terminology (CPT) codes, medications, and CPT-specific complication event rate were included as predictors.

RESULTS

Of 6840 patients, 922 (13.5%) had at least one of the 18 complications tracked by NSQIP. The model achieved 88% specificity, 83% sensitivity, 97% negative predictive value, 52% positive predictive value, and an area under the curve of 0.93.

CONCLUSIONS

Using machine learning on EHR postoperative data linked to NSQIP outcomes data, a model with 163 predictors from the EHR identified complications well at our institution.

Role of Post-Acute Care in Readmissions for Preexisting Healthcare-Associated Infections

OBJECTIVES

Although preventable, healthcare-associated infections (HAIs) are commonly observed in post-acute care settings for at-risk older adults and are a leading cause of hospital readmissions. However, whether HAIs resulting in avoidable readmissions for preexisting HAIs (the same HAI as at the index admission) are more common for patients discharged to post-acute care as opposed to home is unknown. We examined the risk of preexisting HAI readmissions according to patient discharge disposition and comorbidity level.

DESIGN

We used 2013-2014 national hospital discharge data to estimate the likelihood of readmissions for preexisting HAIs according to patients' discharge disposition and whether the likelihood varies according to patient comorbidity level, across four common types of HAIs (not including respiratory infections).

PARTICIPANTS

A total of 702 304 hospital discharges for Medicare beneficiaries 65 years or older.

MEASUREMENTS

Our outcome was a 30-day preexisting, or "linked," HAI readmission (readmission involving the same HAI diagnosis as at the index admission). Patient discharge disposition was skilled nursing facility (SNF), home health care, and home care without home health care ("home").

RESULTS

Of 702 304 index admissions involving HAI treatment, 353 073 (50%) were discharged to a SNF, 179 490 (26%) to home health care, and 169 872 (24%) to home. Overall, 17 523 (2.5%) of preexisting HAIs resulted in linked HAI readmissions, which were more common for Clostridioides difficile infections (4.0%) and urinary tract infections (2.4%) than surgical site infections (1.1%; P < .001). Being discharged to a SNF compared to home or to home health care was associated with a 1.15 percentage point (95% confidence interval = -1.29 to -1.00), or 38%, lower risk of a linked HAI readmission. This risk difference was observed to increase with greater patient comorbidity.

CONCLUSIONS

SNF discharges were associated with fewer avoidable readmissions for preexisting HAIs compared with home discharges. Further research to identify modifiable mechanisms that improve posthospital infection care at home is needed. J Am Geriatr Soc 68:370-378, 2020.

Identification of urinary tract infections using electronic health record data

BACKGROUND

Population ascertainment of postoperative urinary tract infections (UTIs) is time-consuming and expensive, as it often requires manual chart review. Using the American College of Surgeons National Surgical Quality Improvement Program UTI status of patients who underwent an operation at the University of Colorado Hospital, we sought to develop an algorithm for identifying UTIs using data from the electronic health record.

METHODS

Data were split into training (operations occurring between 2013-2015) and test (operations in 2016) sets. A binomial generalized linear model with an elastic-net penalty was used to fit the model and carry out variables selection. International classification of disease codes, common procedural terminology codes, antibiotics, catheterization, and common procedural terminology-specific UTI event rates were included as predictors. The Youden's J statistic was used to determine the optimal classification threshold.

RESULTS

Of 6,840 patients, 134 (2.0%) had a UTI. The model achieved 92% specificity, 80% sensitivity, 100% negative predictive value, 16% positive predictive value, and an area under the curve of 0.94 using a decision threshold of 0.03.

CONCLUSIONS

A model with 14 predictors from the electronic health record identifies UTIs well, and it could be used to scale up UTI surveillance or to estimate the impact of large-scale interventions on UTI rates.

Comparison of hospital surgical site infection rates and rankings using claims versus National Healthcare Safety Network surveillance data

National policies target healthcare-associated infections using medical claims and National Healthcare Safety Network surveillance data. We found low concordance between the 2 data sources in rates and rankings for surgical site infection following colon surgery in 155 hospitals, underscoring the limitations in evaluating hospital quality by claims data.

The Association of Inpatient Occupancy with Hospital-Acquired Clostridium difficile Infection

Few studies have evaluated the relationship between high hospital occupancy and hospital-acquired complications. We evaluated the association between inpatient occupancy and hospital-acquired Clostridium difficile infection (CDI) using a novel measure of hospital occupancy. We analyzed administrative data from California hospitals from 2008-2012 for Medicare recipients aged 65 years with a discharge diagnosis of acute myocardial infarction, heart failure, or pneumonia. Using daily census data, we constructed patient-level measures of occupancy on admission day and average occupancy during hospitalization (range: 0-1), which were split into 4 groups. We used logistic regression with cluster standard errors to estimate the adjusted and unadjusted relationship of occupancy with hospital-acquired CDI. Across 327 hospitals, 558,344 discharges met our inclusion criteria. Higher admission day occupancy was associated with significantly lower adjusted likelihood of CDI. Compared to the 0-0.25 occupancy group, patients admitted on a day of 0.51-0.75 occupancy had 0.86 odds of CDI (95% CI 0.75-0.98). The 0.76-1.00 admission occupancy group had 0.87 odds of CDI (95% CI 0.75-1.01). With regard to average occupancy, intermediate levels of occupancy 0.26-0.50 (odds ratio [OR] = 3.04, 95% CI 2.33-3.96) and 0.51-0.75 (OR = 3.28, 95% CI 2.51-4.28) had over 3-fold increased adjusted odds of CDI relative to the low occupancy group; the high occupancy group did not have signifcantly different odds of CDI compared to the low occupancy group (OR = 0.96, 95% CI 0.70-1.31). These findings should prompt exploration of how hospitals react to occupancy changes and how those care processes translate into hospital-acquired complications in order to inform best practices.

Impact of the 2012 Medicaid Health Care–Acquired Conditions Policy on Catheter-Associated Urinary Tract Infection and Vascular Catheter–Associated Infection Billing Rates

In July 2012, the Centers for Medicare & Medicaid Services ceased hospital Medicaid reimbursements for certain health care–acquired conditions. Using billing data from 2008–2014, we found no impact of this policy on rates of 2 targeted conditions, vascular catheter–associated infections and catheter-associated urinary tract infections, among Medicaid or non-Medicaid patients.

Validity and Reliability of Administrative Coded Data for the Identification of Hospital-Acquired Infections: An Updated Systematic Review with Meta-Analysis and Meta-Regression Analysis

OBJECTIVE

To conduct an updated assessment of the validity and reliability of administrative coded data (ACD) in identifying hospital-acquired infections (HAIs).

METHODS

We systematically searched three libraries for studies on ACD detecting HAIs compared to manual chart review. Meta-analyses were conducted for prosthetic and nonprosthetic surgical site infections (SSIs), Clostridium difficile infections (CDIs), ventilator-associated pneumonias/events (VAPs/VAEs) and non-VAPs/VAEs, catheter-associated urinary tract infections (CAUTIs), and central venous catheter-related bloodstream infections (CLABSIs). A random-effects meta-regression model was constructed.

RESULTS

Of 1,906 references found, we retrieved 38 documents, of which 33 provided meta-analyzable data (N = 567,826 patients). ACD identified HAI incidence with high specificity (≥93 percent), prosthetic SSIs with high sensitivity (95 percent), and both CDIs and nonprosthetic SSIs with moderate sensitivity (65 percent). ACD exhibited substantial agreement with traditional surveillance methods for CDI (κ = 0.70) and provided strong diagnostic odds ratios (DORs) for the identification of CDIs (DOR = 772.07) and SSIs (DOR = 78.20). ACD performance in identifying nosocomial pneumonia depended on the ICD coding system (DORICD-10/ICD-9-CM  = 0.05; p = .036). Algorithmic coding improved ACD's sensitivity for SSIs up to 22 percent. Overall, high heterogeneity was observed, without significant publication bias.

CONCLUSIONS

Administrative coded data may not be sufficiently accurate or reliable for the majority of HAIs. Still, subgrouping and algorithmic coding as tools for improving ACD validity deserve further investigation, specifically for prosthetic SSIs. Analyzing a potential lower discriminative ability of ICD-10 coding system is also a pending issue.

Validity of the Agency for Health Care Research and Quality Patient Safety Indicators and the Centers for Medicare and Medicaid Hospital-acquired Conditions: A Systematic Review and Meta-Analysis

BACKGROUND

The Agency for Health Care Research and Quality Patient Safety Indicators (PSIs) and Centers for Medicare and Medicaid Services Hospital-acquired Conditions (HACs) are increasingly being used for pay-for-performance and public reporting despite concerns over their validity. Given the potential for these measures to misinform patients, misclassify hospitals, and misapply financial and reputational harm to hospitals, these need to be rigorously evaluated. We performed a systematic review and meta-analysis to assess PSI and HAC measure validity.

METHODS

We searched MEDLINE and the gray literature from January 1, 1990 through January 14, 2015 for studies that addressed the validity of the HAC measures and PSIs. Secondary outcomes included the effects of present on admission (POA) modifiers, and the most common reasons for discrepancies. We developed pooled results for measures evaluated by ≥3 studies. We propose a threshold of 80% for positive predictive value or sensitivity for pay-for-performance and public reporting suitability.

RESULTS

Only 5 measures, Iatrogenic Pneumothorax (PSI 6/HAC 17), Central Line-associated Bloodstream Infections (PSI 7), Postoperative hemorrhage/hematoma (PSI 9), Postoperative deep vein thrombosis/pulmonary embolus (PSI 12), and Accidental Puncture/Laceration (PSI 15), had sufficient data for pooled meta-analysis. Only PSI 15 (Accidental Puncture and Laceration) met our proposed threshold for validity (positive predictive value only) but this result was weakened by considerable heterogeneity. Coding errors were the most common reasons for discrepancies between medical record review and administrative databases. POA modifiers may improve the validity of some measures.

CONCLUSION

This systematic review finds that there is limited validity for the PSI and HAC measures when measured against the reference standard of a medical chart review. Their use, as they currently exist, for public reporting and pay-for-performance, should be publicly reevaluated in light of these findings.

Development of administrative data algorithms to identify patients with critical limb ischemia

Administrative data have been used to identify patients with various diseases, yet no prior study has determined the utility of International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM)-based codes to identify CLI patients. CLI cases (n=126), adjudicated by a vascular specialist, were carefully defined and enrolled in a hospital registry. Controls were frequency matched to cases on age, sex and admission date in a 2:1 ratio. ICD-9-CM codes for all patients were extracted. Algorithms were developed using frequency distributions of these codes, risk factors and procedures prevalent in CLI. The sensitivity for each algorithm was calculated and applied within the hospital system to identify CLI patients not included in the registry. Sensitivity ranged from 0.29 to 0.92. An algorithm based on diagnosis and procedure codes exhibited the best overall performance (sensitivity of 0.92). Each algorithm had differing CLI identification characteristics based on patient location. Administrative data can be used to identify CLI patients within a health system. The algorithms, developed from these data, can serve as a tool to facilitate clinical care, research, quality improvement, and population surveillance.

Costs of Venous Thromboembolism, Catheter-Associated Urinary Tract Infection, and Pressure Ulcer

OBJECTIVE

To estimate differences in the length of stay (LOS) and costs for comparable pediatric patients with and without venous thromboembolism (VTE), catheter-associated urinary tract infection (CAUTI), and pressure ulcer (PU).

METHODS

We identified at-risk children 1 to 17 years old with inpatient discharges in the Nationwide Inpatient Sample. We used a high dimensional propensity score matching method to adjust for case-mix at the patient level then estimated differences in the LOS and costs for comparable pediatric patients with and without VTE, CAUTI, and PU.

RESULTS

Incidence rates were 32 (VTE), 130 (CAUTI), and 3 (PU) per 10 000 at-risk patient discharges. Patients with VTE had an increased 8.1 inpatient days (95% confidence interval [CI]: 3.9 to 12.3) and excess average costs of $27 686 (95% CI: $11 137 to $44 235) compared with matched controls. Patients with CAUTI had an increased 2.4 inpatient days (95% CI: 1.2 to 3.6) and excess average costs of $7200 (95% CI: $2224 to $12 176). No statistical differences were found between patients with and without PU.

CONCLUSIONS

The significantly extended LOS highlights the substantial morbidity associated with these potentially preventable events. Hospitals seeking to develop programs targeting VTE and CAUTI should consider the improved turnover of beds made available by each event prevented.

Accuracy of administrative data for surveillance of healthcare-associated infections: a systematic review

OBJECTIVE

Measuring the incidence of healthcare-associated infections (HAI) is of increasing importance in current healthcare delivery systems. Administrative data algorithms, including (combinations of) diagnosis codes, are commonly used to determine the occurrence of HAI, either to support within-hospital surveillance programmes or as free-standing quality indicators. We conducted a systematic review evaluating the diagnostic accuracy of administrative data for the detection of HAI.

METHODS

Systematic search of Medline, Embase, CINAHL and Cochrane for relevant studies (1995-2013). Methodological quality assessment was performed using QUADAS-2 criteria; diagnostic accuracy estimates were stratified by HAI type and key study characteristics.

RESULTS

57 studies were included, the majority aiming to detect surgical site or bloodstream infections. Study designs were very diverse regarding the specification of their administrative data algorithm (code selections, follow-up) and definitions of HAI presence. One-third of studies had important methodological limitations including differential or incomplete HAI ascertainment or lack of blinding of assessors. Observed sensitivity and positive predictive values of administrative data algorithms for HAI detection were very heterogeneous and generally modest at best, both for within-hospital algorithms and for formal quality indicators; accuracy was particularly poor for the identification of device-associated HAI such as central line associated bloodstream infections. The large heterogeneity in study designs across the included studies precluded formal calculation of summary diagnostic accuracy estimates in most instances.

CONCLUSIONS

Administrative data had limited and highly variable accuracy for the detection of HAI, and their judicious use for internal surveillance efforts and external quality assessment is recommended. If hospitals and policymakers choose to rely on administrative data for HAI surveillance, continued improvements to existing algorithms and their robust validation are imperative.

Impact of the Centers for Medicare and Medicaid Services Hospital-Acquired Conditions Policy on Billing Rates for 2 Targeted Healthcare-Associated Infections

BACKGROUND

The 2008 Centers for Medicare & Medicaid Services hospital-acquired conditions policy limited additional payment for conditions deemed reasonably preventable.

OBJECTIVE

To examine whether this policy was associated with decreases in billing rates for 2 targeted conditions, vascular catheter-associated infections (VCAI) and catheter-associated urinary tract infections (CAUTI).

STUDY POPULATION

Adult Medicare patients admitted to 569 acute care hospitals in California, Massachusetts, or New York and subject to the policy. DESIGN We used an interrupted times series design to assess whether the hospital-acquired conditions policy was associated with changes in billing rates for VCAI and CAUTI.

RESULTS

Before the policy, billing rates for VCAI and CAUTI were increasing (prepolicy odds ratio per quarter for VCAI, 1.17 [95% CI, 1.11-1.23]; for CAUTI, 1.19 [1.16-1.23]). The policy was associated with an immediate drop in billing rates for VCAI and CAUTI (odds ratio for change at policy implementation for VCAI, 0.75 [95% CI, 0.69-0.81]; for CAUTI, 0.87 [0.79-0.96]). In the postpolicy period, we observed a decreasing trend in the billing rate for VCAI and a leveling-off in the billing rate for CAUTI (postpolicy odds ratio per quarter for VCAI, 0.98 [95% CI, 0.97-0.99]; for CAUTI, 0.99 [0.97-1.00]).

CONCLUSIONS

The Centers for Medicare & Medicaid Services hospital-acquired conditions policy appears to have been associated with immediate reductions in billing rates for VCAI and CAUTI, followed by a slight decreasing trend or leveling-off in rates. These billing rates, however, may not correlate with changes in clinically meaningful patient outcomes and may reflect changes in coding practices.

Combining structured and unstructured data to identify a cohort of ICU patients who received dialysis

OBJECTIVE

To develop a generalizable method for identifying patient cohorts from electronic health record (EHR) data-in this case, patients having dialysis-that uses simple information retrieval (IR) tools.

METHODS

We used the coded data and clinical notes from the 24,506 adult patients in the Multiparameter Intelligent Monitoring in Intensive Care database to identify patients who had dialysis. We used SQL queries to search the procedure, diagnosis, and coded nursing observations tables based on ICD-9 and local codes. We used a domain-specific search engine to find clinical notes containing terms related to dialysis. We manually validated the available records for a 10% random sample of patients who potentially had dialysis and a random sample of 200 patients who were not identified as having dialysis based on any of the sources.

RESULTS

We identified 1844 patients that potentially had dialysis: 1481 from the three coded sources and 1624 from the clinical notes. Precision for identifying dialysis patients based on available data was estimated to be 78.4% (95% CI 71.9% to 84.2%) and recall was 100% (95% CI 86% to 100%).

CONCLUSIONS

Combining structured EHR data with information from clinical notes using simple queries increases the utility of both types of data for cohort identification. Patients identified by more than one source are more likely to meet the inclusion criteria; however, including patients found in any of the sources increases recall. This method is attractive because it is available to researchers with access to EHR data and off-the-shelf IR tools.

Trends in catheter-associated urinary tract infections among a national cohort of hospitalized adults, 2001-2010

BACKGROUND

Catheter-associated urinary tract infections (CAUTIs) have become a major public health concern in the United States. This study provides national estimates of CAUTI incidence, mortality, and associated hospital length of stay (LOS) over a 10-year period.

METHODS

This was a retrospective analysis of the National Hospital Discharge Surveys from 2001 to 2010. Adults age ≥18 years with an International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) procedure code for urinary catheter placement or other major procedure were included. Urinary tract infections were identified by ICD-9-CM code. Data weights were applied to derive national estimates. Predictors of CAUTI were identified using a logistic regression model.

RESULTS

These data represent 70.4 million catheterized patients, 3.8 million of whom developed a CAUTI. The incidence of CAUTIs decreased from 9.4 cases/100 catheterizations in 2001 to 5.3 cases/100 catheterizations in 2010. Mortality in patients with a CAUTI declined from 5.4% in 2001 to 3.7% in 2010. Median (interquartile range [IQR]) hospital LOS also declined, from 9 days (IQR, 5-16 days) in 2001 to 7 days (IQR, 4-12 days) in 2010. Independent predictors of CAUTI included female sex, emergency hospital admission, transfer from another facility, and Medicaid payment (P < .0001 for all variables).

CONCLUSIONS

The incidence of CAUTIs in US hospitals declined over the study period. Furthermore, patients with these infections experienced lower hospital mortality and shorter hospital LOS.

Identification of device-associated infections utilizing administrative data

BACKGROUND

Health care-associated infections are a cause of significant morbidity and mortality in US hospitals. Recent changes have broadened the scope of health care-associated infections surveillance data to use in public reporting and of administrative data for determining Medicare reimbursement adjustments for hospital-acquired conditions.

METHODS

Infection surveillance results for catheter-associated urinary tract infections (CAUTI), central line-associated bloodstream infections (CLABSI), and ventilator-associated pneumonia were compared with infections identified by hospital administrative data. The sensitivity and specificity of administrative data were calculated, with surveillance data considered the gold standard.

RESULTS

The sensitivity of administrative data diagnosis codes for CAUTI, CLABSI, and ventilator-associated pneumonia were 0%, 21%, and 25%, respectively. The incorporation of additional diagnosis codes in definitions increased the sensitivity of administrative data somewhat with little decrease in specificity. Positive predictive values for definitions corresponding to Centers for Medicare and Medicaid services-defined hospital-acquired conditions were 0% for CAUTI and 41% for CLABSI.

CONCLUSIONS

Although infection surveillance methods and administrative data are widely used as tools to identify health care-associated infections, in our study administrative data failed to identify the same infections that were detected by surveillance. Hospitals, already incentivized by the use of performance measures to improve the quality of patient care, should also recognize the need for ongoing scrutiny of appropriate quality measures.

Medicare non-payment of hospital-acquired infections: infection rates three years post implementation

BACKGROUND

Medicare ceased payment for some hospital-acquired infections beginning October 1, 2008, following provisions in the Medicare Modernization Act of 2003 and the Deficit Reduction Act of 2005.

OBJECTIVE

We examined the association of this policy with declines in rates of vascular catheter-associated infections (VCAI) and catheter-associated urinary tract infection (CAUTI).

DATA

Discharge data from the Florida Agency for Healthcare Administration from 2007 to 2011.

STUDY DESIGN

We compared rates of hospital-acquired vascular catheter-associated infections (HA-VCAI) and catheter-associated urinary tract infections (HA-CAUTI) before and after implementation of the new policy (January 2007 to September 2008 vs. October 2008 to September 2011). This pre-post, retrospective, interrupted time series study was further analyzed with a generalized hierarchical logistic regression, by estimating the probability of a patient acquiring these infections in the hospital, post-policy compared to pre-policy.

PRINCIPAL FINDINGS

Pre-policy, 0.12% of admitted patients were diagnosed with CAUTI; of these, 32% were HA-CAUTI. Similarly, 0.24% of admissions were diagnosed as VCAI; of these, 60% were HA-VCAI. Post-policy, 0.16% of admissions were CAUTIs; of these, 31% were HA-CAUTI. Similarly, 0.3% of admissions were VCAIs and, of these, 45% were HA-VCAI. There was a statistically significant decrease in HA-VCAIs (OR: 0.571 (p < 0.0001)) post-policy, but the reduction in HA-CAUTI (OR: 0.968 (p < 0.4484)) was not statistically significant.

CONCLUSIONS

The results suggest Medicare non payment policy is associated with both a decline in the rate of hospital-acquired VCAI (HA-VCAI) per quarter, and the probability of acquiring HA-VCAI post- policy. The strength of the association could be overestimated, because of concurrent ongoing infection control interventions.

Postoperative Urinary Tract Infection and Short-Term Outcomes and Costs in Head and Neck Cancer Surgery

Objectives

Catheter-associated urinary tract infections (UTIs) have been identified as a preventable “never event” by the Centers for Medicare & Medicaid Services. We sought to determine the relationship between UTI and in-hospital mortality, postoperative complications, length of stay, and costs in head and neck cancer (HNCA) surgery.

Study Design

Cross-sectional analysis using cross-tabulations and multivariate regression modeling.

Setting

The Nationwide Inpatient Sample database.

Subjects and Methods

Discharge data for 93,663 patients who underwent an ablative procedure for a malignant oral cavity, laryngeal, hypopharyngeal, or oropharyngeal neoplasm in 2003-2008 were analyzed.

Results

Urinary tract infection was diagnosed in 2% of patients, with catheter-associated UTI coded in only 20 patients. Patients with UTI were more likely to be older than 80 years (odds ratio [OR], 3.3; P = .008), be female (OR, 1.9; P < .001), have advanced comorbidity (OR, 1.8; P < .012), undergo major surgical procedures (OR, 1.7; P = .001), and have predisposing bladder and prostate conditions (OR, 3.8; P < .001), surgical complications (OR, 2.3; P < .001), and acute medical complications (OR, 3.1; P < .001). Urinary tract infection was associated with significantly increased length of hospitalization and hospital-related costs, after controlling for all other variables.

Conclusion

Urinary tract infection is unusual in HNCA surgical patients but is more common with extent of surgery and age and is significantly associated with postoperative complications, length of hospitalization, and hospital-related costs. Catheter-associated UTI is likely underestimated because of difficulty in distinguishing between a catheter-associated UTI and postoperative UTI in patients undergoing major surgical procedures, who routinely undergo perioperative urinary catheterization. Patients with HNCA are a high-risk group for this “never event,” particularly as the population ages.

Effect of nonpayment for preventable infections in U.S. hospitals

BACKGROUND

In October 2008, the Centers for Medicare and Medicaid Services (CMS) discontinued additional payments for certain hospital-acquired conditions that were deemed preventable. The effect of this policy on rates of health care-associated infections is unknown.

METHODS

Using a quasi-experimental design with interrupted time series with comparison series, we examined changes in trends of two health care-associated infections that were targeted by the CMS policy (central catheter-associated bloodstream infections and catheter-associated urinary tract infections) as compared with an outcome that was not targeted by the policy (ventilator-associated pneumonia). Hospitals participating in the National Healthcare Safety Network and reporting data on at least one health care-associated infection before the onset of the policy were eligible to participate. Data from January 2006 through March 2011 were included. We used regression models to measure the effect of the policy on changes in infection rates, adjusting for baseline trends.

RESULTS

A total of 398 hospitals or health systems contributed 14,817 to 28,339 hospital unit-months, depending on the type of infection. We observed decreasing secular trends for both targeted and nontargeted infections long before the policy was implemented. There were no significant changes in quarterly rates of central catheter-associated bloodstream infections (incidence-rate ratio in the postimplementation vs. preimplementation period, 1.00; P=0.97), catheter-associated urinary tract infections (incidence-rate ratio, 1.03; P=0.08), or ventilator-associated pneumonia (incidence-rate ratio, 0.99; P=0.52) after the policy implementation. Our findings did not differ for hospitals in states without mandatory reporting, nor did it differ according to the quartile of percentage of Medicare admissions or hospital size, type of ownership, or teaching status.

CONCLUSIONS

We found no evidence that the 2008 CMS policy to reduce payments for central catheter-associated bloodstream infections and catheter-associated urinary tract infections had any measurable effect on infection rates in U.S. hospitals. (Funded by the Agency for Healthcare Research and Quality.).

Adoption of policies to prevent catheter-associated urinary tract infections in United States intensive care units

BACKGROUND

Little is known about whether recommended strategies to prevent catheter-associated urinary tract infection (CAUTI) are being implemented in intensive care units (ICU) in the United States.

OBJECTIVES

Our objectives were to describe the presence of and adherence to CAUTI prevention policies in ICUs, to identify variations in policies based on organizational characteristics, and to determine whether a relationship exists between prevention policies and CAUTI incidence rates.

METHODS

Four hundred forty-one hospitals that participate in the National Healthcare Safety Network were surveyed in spring 2008.

RESULTS

Two hundred fifty hospitals provided information for 415 ICUs (response rate, 57%). A small proportion of ICUs surveyed had policies supporting bladder ultrasound (26%, n = 106), condom catheters (20%, n = 82), catheter removal reminders (12%, n = 51), or nurse-initiated catheter discontinuation (10%, n = 39). ICUs in hospitals with ≥ 500 beds were half as likely as those in smaller hospitals to have adopted at least 1 CAUTI prevention policy (odds ratio, 0.52; 95% confidence interval: 0.33-0.86), and ICUs in hospitals where the infection control director reported always having access to key decision makers for planning were more than twice as likely as those with less access to have adopted a policy (odds ratio, 2.41; 95% confidence interval: 1.56-3.72).

CONCLUSION

Little attention is currently placed on CAUTI prevention in ICUs in the United States. Further research is needed to elucidate relationships between adherence to CAUTI prevention recommendations and CAUTI incidence rates.

Chief nursing officers' perspectives on Medicare's hospital-acquired conditions non-payment policy: implications for policy design and implementation

BACKGROUND

Preventable adverse events from hospital care are a common patient safety problem, often resulting in medical complications and additional costs. In 2008, Center for Medicare and Medicaid Services (CMS) implemented a policy, mandated by the Deficit Reduction Act of 2005, targeting a list of these 'reasonably' preventable hospital-acquired conditions (HACs) for reduced reimbursement. Extensive debate ensued about the potential adverse effects of the policy, but there was little discussion of its impact on hospitals' quality improvement (QI) activities. This study's goals were to understand organizational responses to the HAC policy, including internal and external influences that moderated the success or failure of QI efforts.

METHODS

We employed a qualitative descriptive design. Representatives from 14 Nurses Improving Care of Health System Elders (NICHE) hospitals participated in semi-structured interviews addressing the impact of the HAC policy generally, and for two indicator conditions: central-line associated bloodstream infection (CLABSI) and catheter-associated urinary tract infection (CAUTI). Within-case analysis identified the key components of each institution's response to the policy; across-case analysis identified themes. Exemplar cases were used to explicate findings.

RESULTS

Interviewees reported that the HAC policy is one of many internal and external factors motivating hospitals to address HACs. They agreed the policy focused attention on prevention of HACs that had previously received fewer dedicated resources. The impact of the policy on prevention activities, barriers, and facilitators was condition-specific. CLABSI efforts were in place prior to the policy, whereas CAUTI efforts were less mature. Nearly all respondents noted that pressure ulcer detection and documentation became a larger focus stemming from the policy change. A major challenge was the determination of which conditions were 'hospital-acquired.' One opportunity arising from the policy has been the focus on nursing leadership in patient safety efforts.

CONCLUSIONS

While the CMS's HAC policy was just one of many factors influencing QI efforts, it may have served the important role of drawing attention and resources to the targeted conditions-particularly those not previously in the spotlight. The translational research paradigm is helpful in the interpretation of the findings, illustrating how the policy can advance prevention efforts for HACs at earlier phases of research translation as well as pitfalls associated with earlier phase implementation. To maximize their impact, such policies should consider condition-specific contextual factors influencing policy uptake and provide condition-specific implementation support.

Rural relevant quality measures for critical access hospitals

PURPOSE

To identify current and future relevant quality measures for Critical Access Hospitals (CAHs).

METHODS

Three criteria (patient volume, internal usefulness for quality improvement, and external usefulness for public reporting and payment reform) were used to analyze quality measures for their relevance for CAHs. A 6-member panel with expertise in rural hospital quality measurement and improvement provided input regarding the final measure selection.

FINDINGS

The relevant quality measures for CAHs include measures that are ready for reporting now and measures that need specifications to be finalized and/or a data reporting mechanism to be established. They include inpatient measures for specific medical conditions, global measures that address appropriate care across multiple medical conditions, and Emergency Department measures.

CONCLUSIONS

All CAHs should publicly report on relevant quality measures. Acceptance of a single consolidated set of quality measures with common specifications for CAHs by all entities involved in regulation, accreditation, and payment; a phased process to implement the relevant measures; and the provision of technical assistance would help CAHs meet the challenge of reporting.

Increasing burden of methicillin-resistant Staphylococcus aureus hospitalizations at US academic medical centers, 2003-2008

OBJECTIVE

The incidence of invasive methicillin-resistant Staphylococcus aureus (MRSA) infections in the United States decreased during 2005-2008, but noninvasive community-associated MRSA (CA-MRSA) infections also frequently lead to hospitalization. We estimated the incidence of all MRSA infections among inpatients at US academic medical centers (AMCs) per 1,000 admissions during 2003-2008.

DESIGN

Retrospective cohort study.

SETTING AND PARTICIPANTS

Hospitalized patients at 90% of nonprofit US AMCs during 2003-2008.

METHODS

Administrative data on MRSA infections from a hospital discharge database (University HealthSystem Consortium [UHC]) were adjusted for underreporting of the MRSA V09.0 International Classification of Diseases, Ninth Revision, Clinical Modification code and validated using chart reviews for patients with known MRSA infections in 2004-2005, 2006, and 2007.

RESULTS

The mean sensitivity of administrative data for MRSA infections at the University of Chicago Medical Center in three 12-month periods during 2004-2007 was 59.1%. On the basis of estimates of billing data sensitivity from the literature and the University of Chicago Medical Center, the number of MRSA infections per 1,000 hospital discharges at US AMCs increased from 20.9 (range, 11.1-47.7) in 2003 to 41.7 (range, 21.9-94.0) in 2008. At the University of Chicago Medical Center, among infections cultured more than 3 days prior to hospital discharge, CA-MRSA infections were more likely to be captured in the UHC billing-derived data than were healthcare-associated MRSA infections.

CONCLUSIONS

The number of hospital admissions for any MRSA infection per 1,000 hospital admissions overall increased during 2003-2008. Use of unadjusted administrative hospital discharge data or surveillance for invasive disease far underestimates the number of MRSA infections among hospitalized patients.

Enhancing Medicare's hospital-acquired conditions policy to encompass readmissions

BACKGROUND

The current Medicare policy of non-payment to hospitals for Hospital-Acquired Conditions (HAC) seeks to avoid payment for preventable complications identified within a single admission. The financial impact ($1 million-$50 million/yr) underestimates the true financial impact of HACs when readmissions are taken into account.

OBJECTIVE

Define and quantify acute inpatient readmissions arising directly from, or completing the definition of, the current HACs.

RESEARCH DESIGN

Observational study.

SUBJECTS

All non-federal inpatient admissions to California hospitals, July 2006 to June 2007 with a recorded Social Security number.

MEASURES

Readmission to acute care within 1 day for acute complications of poor glycemic control; 7 days for iatrogenic air emboli, incompatible blood transfusions, catheter-associated urinary tract infections and vascular catheter-associated infections; 30 days for deep vein thromboses or pulmonary emboli following hip or knee replacement surgery; and 183 days for foreign objects retained after surgery, mediastinitis following coronary artery bypass grafts, injuries sustained during inpatient care, infections following specific joint or bariatric surgery procedures, and pressure ulcers stages III & IV.

RESULTS

An additional estimated $103 million in payments would be withheld if Medicare expands the policy to include non-payment for HAC related readmissions. The majority (90%) of this impact involves mediastinitis, post-orthopedic surgery infection, or fall related injury.

CONCLUSIONS

Limiting the current HAC policy focus to complications identified during the index admission omits consideration of many complications only identified in a subsequent admission. Non-payment for HAC-related readmissions would enhance incentives for prevention by increasing the frequency with which hospitals are held accountable for HACs.

Guidelines to prevent catheter-associated urinary tract infection: 1980 to 2010

OBJECTIVES

We set out to review and compare guidelines to prevent catheter-associated urinary tract infection (CAUTI), examine the association between recent federal initiatives and CAUTI guidelines, and recommend practices for preventing CAUTI that are associated with strong evidence and are consistent across guidelines.

BACKGROUND

Catheter-associated urinary tract infections are the most common healthcare-associated infection, and a cause of significant morbidity and mortality in critically ill patients.

METHODS

A search of the English-language literature for guidelines in the prevention of adult CAUTI, published between 1980 and 2010, was conducted in Medline and the National Guideline Clearinghouse.

RESULTS

Many recommendations were consistent across 8 guidelines, including limited use of urinary catheters, the insertion of catheters aseptically, and the maintenance of a closed drainage system. The weight of evidence for some endorsed practices was limited, and different grading systems made comparisons across recommendations difficult. Federal initiatives are closely aligned with the 4 most recent guidelines.

CONCLUSION

Additional research into the prevention of CAUTI is needed, as is a harmonization of guideline grading systems for recommendations.

Accuracy of a urinary catheter surveillance protocol

BACKGROUND

Many hospitals are increasing surveillance for catheter-associated urinary tract infections, which requires documentation of urinary catheter device-days. However, device-days are usually obtained by chart review or nursing reports. The aim of this study was to demonstrate that chart review can provide accurate urinary catheter data compared with physical inspection of the urinary catheter at the bedside.

METHODS

We compared 2 methods for collecting urinary catheter data over a 6-month period on 10 wards at our VA hospital. For the chart reviews, we created a daily bed-occupancy roster from the electronic medical record. Catheter data were extracted from the daily progress notes for each patient using a standardized review process. Bedside reviews were conducted by visiting the ward and verifying the presence and type of urinary catheters. Agreement between the 2 methods was calculated.

RESULTS

We obtained urinary catheter data by both methods in 621 cases. The presence or type of urinary catheter differed between chart and bedside review in only 10 cases (1.6%). Chart review had a sensitivity of 100%, a specificity of 97.7%, raw agreement of 98.4%, and a κ value of 0.96.

CONCLUSIONS

Individual chart review in the electronic medical record provided very accurate data on urinary catheter use.

The Medicare policy of payment adjustment for health care-associated infections: perspectives on potential unintended consequences

In 2008, the Centers for Medicare & Medicaid Services introduced a new policy to adjust payment to hospitals for health care-associated infections (HAIs) not present on admission. Interviews with 36 hospital infection preventionists across the United States explored the perspectives of these key stakeholders on the potential unintended consequences of the current policy. Responses were analyzed using an iterative coding process where themes were developed from the data. Participants' descriptions of unintended impacts of the policy centered around three themes. Results suggest the policy has focused more attention on targeted HAIs and has affected hospital staff; relatively fewer systems changes have ensued. Some consequences of the policy, such as infection preventionists having less time to devote to HAIs other than those in the policy or having less time to implement prevention activities, may have undesirable effects on HAI rates if hospitals do not recognize and react to potential time and resource gaps.

Total Abdominal Colectomy Has a Similar Short-Term Outcome Profile Regardless of Indication: Data from the National Surgical Quality Improvement Program

The purpose of this study was to evaluate the 30-day postoperative complications rate in patients undergoing elective total abdominal colectomy (TAC) for chronic constipation, neoplastic disorders, and inflammatory bowel disease (IBD) using the American College of Surgeons National Quality Improvement Database (ACS-NSQIP). The 2007 ACS-NSQIP sample was used to identify the Current Procedural Terminology codes for TAC and International Classification of Diseases, 9th Revision codes for chronic constipation, neoplasia, and IBD. Preoperative and intraoperative variables and postoperative complications were compared among the three diagnosis groups. Wilcoxon rank sum and Fisher exact tests were used for analysis. P < 0.05 was considered significant. Seven hundred forty-four patients were identified; chronic constipation was found in 107 (14.4%) patients, neoplasia in 312 (42.3%), and IBD in 322 (43.3%). Patients with constipation were predominantly females (85.2%). The neoplastic group was older and had greater body mass index when compared with the other groups. Patients with IBD presented greater use of steroids, lower albumin and hematocrit levels, and higher morbidity probability. Constipated patients had more neurologic and renal complications when compared with the IBD group ( P = 0.01). None of the other categories of complications were statistically different among the diagnosis groups. With the exception of urinary tract infection being higher in the constipation patients compared with IBD (10 vs 4%, P = 0.03), there were no statistically significant differences among the other short-term specific complications. The 30-day complication rate after TAC is similar for chronic constipation, neoplasia, and IBD.

A comparison of methods to detect urinary tract infections using electronic data

BACKGROUND

The use of electronic medical records to identify common health care-associated infections (HAIs), including pneumonia, surgical site infections, bloodstream infections, and urinary tract infections (UTIs), has been proposed to help perform HAI surveillance and guide infection prevention efforts. Increased attention on HAIs has led to public health reporting requirements and a focus on quality improvement activities around HAIs. Traditional surveillance to detect HAIs and focus prevention efforts is labor intensive, and computer algorithms could be useful to screen electronic data and provide actionable information.

METHODS

Seven computer-based decision rules to identify UTIs were compared in a sample of 33,834 admissions to an urban academic health center. These decision rules included combinations of laboratory data, patient clinical data, and administrative data (for example, International Statistical Classification of Diseases and Related Health Problems, Ninth Revision [ICD-9] codes).

RESULTS

Of 33,834 hospital admissions, 3,870 UTIs were identified by at least one of the decision rules. The use of ICD-9 codes alone identified 2,614 UTIs. Laboratory-based definitions identified 2,773 infections, but when the presence of fever was included, only 1,125 UTIs were identified. The estimated sensitivity of ICD-9 codes was 55.6% (95% confidence interval [CI], 52.5%-58.5%) when compared with a culture- and symptom-based definition. Of the UTIs identified by ICD-9 codes, 167/1,125 (14.8%) also met two urine-culture decision rules.

DISCUSSION

Use of the example of UTI identification shows how different algorithms may be appropriate, depending on the goal of case identification. Electronic surveillance methods may be beneficial for mandatory reporting, process improvement, and economic analysis.

Hospital-acquired catheter-associated urinary tract infection: documentation and coding issues may reduce financial impact of Medicare's new payment policy

OBJECTIVE

To evaluate whether hospital-acquired catheter-associated urinary tract infections (CA-UTIs) are accurately documented in discharge records with the use of International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes so that nonpayment is triggered, as mandated by the Centers for Medicare and Medicaid Services (CMS) Hospital-Acquired Conditions Initiative.

METHODS

We conducted a retrospective medical record review of 80 randomly selected adult discharges from May 2006 through September 2007 from the University of Michigan Health System (UMHS) with secondary-diagnosis urinary tract infections (UTIs). One physician-abstractor reviewed each record to categorize UTIs as catheter associated and/or hospital acquired; these results (considered "gold standard") were compared with diagnosis codes assigned by hospital coders. Annual use of the catheter association code (996.64) by UMHS coders was compared with state and US rates by using Healthcare Cost and Utilization Project data.

RESULTS

Patient mean age was 58 years; 56 (70%) were women; median length of hospital stay was 6 days; 50 patients (62%) used urinary catheters during hospitalization. Hospital coders had listed 20 secondary-diagnosis UTIs (25%) as hospital acquired, whereas physician-abstractors indicated that 37 (46%) were hospital acquired. Hospital coders had identified no CA-UTIs (code 996.64 was never used), whereas physician-abstractors identified 36 CA-UTIs (45%; 28 hospital acquired and 8 present on admission). Catheter use often was evident only from nursing notes, which, unlike physician notes, cannot be used by coders to assign discharge codes. State and US annual rates of 996.64 coding (approximately 1% of secondary-diagnosis UTIs) were similar to those at UMHS.

CONCLUSIONS

Hospital coders rarely use the catheter association code needed to identify CA-UTI among secondary-diagnosis UTIs. Coders often listed a UTI as present on admission, although the medical record indicated that it was hospital acquired. Because coding of hospital-acquired CA-UTI seems to be fraught with error, nonpayment according to CMS policy may not reliably occur.

Medical complications in patients with stroke: data validity in a stroke registry and a hospital discharge registry

Background:

Stroke patients frequently experience medical complications; yet, data on incidence, causes, and consequences are sparse.

Objective:

To examine the data validity of medical complications among patients with stroke in a population-based clinical registry and a hospital discharge registry.

Methods:

We examined the predictive values, sensitivity and specificity of medical complications among patients admitted to specialized stroke units and registered in the Danish National Indicator Project (DNIP) and the Danish National Registry of Patients (NRP) between January 2003 and December 2006 (n = 8,024). We retrieved and reviewed medical records from a random sample of patients (n = 589, 7.3%).

Results:

We found substantial variation in the data quality of stroke-related medical complication diagnoses both within the specific complications and between the registries. The positive predictive values ranged from 39.0%–87.1% in the DNIP, and from 0.0%–92.9% in the NRP. The negative predictive values ranged from 71.6%–98.9% in the DNIP and from 63.3% to 97.4% in the NRP. In both registries the specificity of the diagnoses was high. The sensitivity ranged from 23.5% (95% confidence interval [CI]: 14.9–35.4) for falls to 62.9% (95% CI: 54.9–70.4) for urinary infection in the DNIP, and from 0.0 (95% CI: 0.0–4.99) for falls to 18.1% (95% CI: 2.3–51.8) for pressure ulcer in the NRP.

Conclusion:

The DNIP may be useful for studying medical complications among patients with stroke.

Recurrent venous thromboembolism after surgery-provoked versus unprovoked thromboembolism

SUMMARY BACKGROUND

The incidence of recurrent venous thromboembolism (VTE) varies depending on the nature of the initial provoking risk factor(s).

OBJECTIVES

To compare the incidence and time course of recurrent VTE after unprovoked VTE vs. VTE provoked by nine different types of surgery.

METHODS

Retrospective analysis of linked California hospital and emergency department discharge records. Between 1997 and 2007, all surgery-provoked VTE cases had a first-time VTE event diagnosed within 60 days after undergoing a major operation. The incidence of recurrent VTE was compared during specified follow-up periods by matching each surgery-provoked case with three unprovoked cases based on age, race, gender, VTE event, calendar year and co-morbidity.

RESULTS

The 4-year Kaplan-Meier cumulative incidence of recurrent VTE was 14.7% (95%CI: 14.2-15.1) in the matched unprovoked VTE group vs. 7.6% (CI: 7.0-8.2) in 11 797 patients with surgery-provoked VTE (P < 0.001). The overall risk reduction was 48%, which ranged from 64% lower risk (P < 0.001) after coronary bypass surgery to 25% lower risk (P = 0.06) after disc surgery. The risk of recurrent VTE 1-5 years after the index event was significantly lower in the surgery group (HR = 0.47, CI: 0.41-0.53). Within the surgery-provoked group, the risk of recurrent VTE was similar in men and women (HR = 1.0, CI: 0.8-1.3).

CONCLUSIONS

The risk of recurrent VTE after surgery-provoked VTE was approximately 50% lower than after unprovoked VTE, confirming the view that provoked VTE is associated with a lower risk of recurrent VTE. However, there was appreciable heterogeneity in the relative risk of recurrent VTE associated with different operations.