Population mobility, globalization, and antimicrobial drug resistance.

Population mobility is a main factor in globalization of public health threats and risks, specifically distribution of antimicrobial drug-resistant organisms. Drug resistance is a major risk in healthcare settings and is emerging as a problem in community-acquired infections. Traditional health policy approaches have focused on diseases of global public health significance such as tuberculosis, yellow fever, and cholera; however, new diseases and resistant organisms challenge existing approaches. Clinical implications and health policy challenges associated with movement of persons across barriers permeable to products, pathogens, and toxins (e.g., geopolitical borders, patient care environments) are complex. Outcomes are complicated by high numbers of persons who move across disparate and diverse settings of disease threat and risk. Existing policies and processes lack design and capacity to prevent or mitigate adverse health outcomes. We propose an approach to global public health risk management that integrates population factors with effective and timely application of policies and processes.

Identification of hospital-acquired catheter-associated urinary tract infections from Medicare claims: sensitivity and positive predictive value.

BACKGROUND AND OBJECTIVE: Hospital-acquired catheter-associated urinary tract infection (CAUTI) is one of the first 6 conditions Medicare is targeting to reduce payment associated with hospital-acquired conditions under Congressional mandate. This study was to determine the positive predictive value (PPV) and sensitivity in identifying patients in Medicare claims who had urinary catheterization and who had hospital-acquired CAUTIs. RESEARCH DESIGN: CAUTIs identified by ICD-9-CM codes in Medicare claims were compared with those revealed by medical record abstraction in random samples of Medicare discharges in 2005 to 2006. Hospital discharge abstracts (2005) from the states of New York and California were used to estimate the potential impact of a present-on-admission (POA) indicator on PPV. RESULTS: ICD-9-CM procedure codes for urinary catheterization appeared in only 1.4% of Medicare claims for patients who had urinary catheters. As a proxy, claims with major surgery had a PPV of 75% and sensitivity of 48%, and claims with any surgical procedure had a PPV of 53% and sensitivity of 79% in identifying urinary catheterization. The PPV and sensitivity for identifying hospital-acquired CAUTIs varied, with the PPV at 30% and sensitivity at 65% in claims with major surgery. About 80% of the secondary diagnosis codes indicating UTIs were flagged as POA, suggesting that the addition of POA indicators in Medicare claims would increase PPV up to 86% and sensitivity up to 79% in identifying hospital-acquired CAUTIs. CONCLUSIONS: The validity in identifying urinary catheter use and CAUTIs from Medicare claims is limited, but will be increased substantially upon addition of a POA indicator.

Cardiac device implantation in the United States from 1997 through 2004: a population-based analysis.

OBJECTIVE: Use of cardiac devices has been increasing rapidly along with concerns over their safety and effectiveness. This study used hospital administrative data to assess cardiac device implantations in the United States, selected perioperative outcomes, and associated patient and hospital characteristics. METHODS: We screened hospital discharge abstracts from the 1997-2004 Healthcare Cost and Utilization Project Nationwide Inpatient Samples. Patients who underwent implantation of pacemaker (PM), automatic cardioverter/defibrillator (AICD), or cardiac resynchronization therapy pacemaker (CRT-P) or defibrillator (CRT-D) were identified using ICD-9-CM procedure codes. Outcomes ascertainable from these data and associated hospital and patient characteristics were analyzed. MEASUREMENTS AND MAIN RESULTS: Approximately 67,000 AICDs and 178,000 PMs were implanted in 2004 in the United States, increasing 60% and 19%, respectively, since 1997. After FDA approval in 2001, CRT-D and CRT-P reached 33,000 and 7,000 units per year in the United States in 2004. About 70% of the patients were aged 65 years or older, and more than 75% of the patients had 1 or more comorbid diseases. There were substantial decreases in length of stay, but marked increases in charges, for example, the length of stay of AICD implantations halved (from 9.9 days in 1997 to 5.2 days in 2004), whereas charges nearly doubled (from $66,000 in 1997 to $117,000 in 2004). Rates of in-hospital mortality and complications fluctuated slightly during the period. Overall, adverse outcomes were associated with advanced age, comorbid conditions, and emergency admissions, and there was no consistent volume-outcome relationship across different outcome measures and patient groups. CONCLUSIONS: The numbers of cardiac device implantations in the United States steadily increased from 1997 to 2004, with substantial reductions in length of stay and increases in charges. Rates of in-hospital mortality and complications changed slightly over the years and were associated primarily with patient frailty.

Observed association between antidepressant use and pneumonia risk was confounded by comorbidity measures.

OBJECTIVE: A prior study suggested that antidepressants might increase the risk of hospitalization for pneumonia in the elderly. This study sought to confirm or refute this hypothesis. STUDY DESIGN AND SETTING: Case-control study of persons aged 65 and above nested in the UK General Practice Research Database. RESULTS: We identified 12,044 cases of the hospitalization for pneumonia (the primary outcome) and 48,176 controls. The odds ratio (OR) for any antidepressant use, adjusting for age, sex, and calendar year was 1.61 (95% confidence interval 1.46-1.78). After further adjustment for comorbidity measures, the OR was 0.89 (0.79-1.00). We also identified 159 cases of hospitalization for aspiration pneumonia (the secondary outcome) and 636 controls. The OR for any antidepressant use, adjusted for age, sex, and calendar year was 1.45 (0.65-3.24). After further adjustment for comorbidity measures, the OR was 0.63 (0.23-1.71). CONCLUSION: These findings refute the prior hypothesis that use of antidepressants by elderly patients increases the risk of hospitalization for pneumonia or for aspiration pneumonia. Decisions regarding use of antidepressants in elderly persons should not be affected by concern about pneumonia risk. Data-derived hypotheses should be independently confirmed before being acted upon.

An analysis of administrative data found that proximate clinical event ratios provided a systematic approach to identifying possible iatrogenic risk factors or complications.

OBJECTIVE: A method to generate hypotheses about iatrogenic risk factors and complications from administrative data was developed and tested using hospitalization of the elderly for depression as a model. STUDY DESIGN AND SETTING: Hospital claims were selected for 30,998 elderly inpatients admitted for the first time for depression. Common principal diagnoses and procedures in hospitalizations within 90 days of the index depression admission were tallied. For each of these proximate clinical events, the ratio of how many happened before the index admission to how many occurred afterward was calculated. Ratios diverging markedly from unity were identified to generate hypotheses about possible risk factors associated with depression and complications associated with its management. RESULTS: Hospitalization for degenerative joint disease or back problems; abdominal pain or gastritis and duodenitis; coronary artery disease; or cerebrovascular disease was more common before an index depression admission than after it, as were coronary artery surgery, total knee replacement, and cholecystectomy. Admissions for fracture of the femoral neck--an established iatrogenic complication--were disproportionately likely after the index admission. So were admissions for aspiration pneumonia or acute respiratory failure. CONCLUSION: Proximate clinical event ratios provide a systematic approach to screening administrative data to identify candidates for further evaluation as possible iatrogenic risk factors or complications.

Systematic screening of secondary diagnoses in Medicare administrative data to identify candidate risk factors for the principal diagnosis.

PURPOSE: Secondary diagnoses in Medicare hospital discharge claims may include risk factors for the principal diagnosis. However, risk ratios for the principal diagnosis as a function of secondary diagnoses cannot be calculated because no comparable data exist for beneficiaries who are not hospitalized. METHODS: Hospital discharge rates, as proxies for incidence rates, can be calculated by race and sex from Medicare claims and denominator files. If the prevalence of a risk factor is higher in one population group than another, that risk factor will be overrepresented among patients from the group at higher risk. RESULTS: This imbalance is reflected in what is termed the odds difference, OD=[(r+r')/r][f(2)/(1- f(2))-f(1)/(1-f(1))], in which r is the background incidence rate, and r' is the additional risk conferred by a factor that is present in fractions f(1) and f(2) in the two groups. Unlike the risk ratio, the odds difference can be calculated from claims data. Given f(1) and f(2), the odds difference is directly proportional to the risk ratio, RR=(r+r')/r. CONCLUSIONS: Ranking common secondary diagnoses by the magnitude of their odds difference between groups with disparate discharge rates for a given principal diagnosis may disclose secondary diagnoses that merit evaluation as candidate direct or indirect risk factors.

Using science to advance wound care practice: lessons from the literature.

Wound care professionals can improve clinical, patient-oriented wound outcomes and do so cost-effectively by using scientific evidence to meet patient and wound care goals and needs. A review of the literature was conducted to define evidence-based wound management, describe the potential of science to improve outcomes in wound care, and summarize strategies, tactics, and tools for wound care providers and recipients to utilize science to their mutual benefit. In addition, changes in the availability of randomized and nonrandomized and clinical and preclinical evidence during the past 50 years were examined using MEDLINE database searches of English-language publications, combining the search terms wound, ulcer, or burn limited by the terms randomized or clinical for each decade since 1960. The number of published, nonrandomized wound studies has increased exponentially during the last five decades but, more recently, evidence from randomized controlled trials also has become available. Moreover, while many questions remain unanswered, a substantial number of publications have shown the use of available evidence-based guidelines and wound care strategies improves outcomes of care while saving time and money. The application of science-based wound care in clinical practice is increasing slowly; expensive techniques supported by limited or inconsistent evidence are still in use and add to wound care costs without certainty they improve outcomes. The literature provides compelling evidence that patients with a wide variety of diagnoses benefit when opinion-based care is replaced by clinical wisdom applied on a substrate of best available evidence. Patients with wounds deserve no less.

Projected cost-effectiveness of new vaccines for adolescents in the United States.

BACKGROUND: Economic assessments that guide policy making on immunizations are becoming increasingly important in light of new and anticipated vaccines for adolescents. However, important considerations that limit the utility of these assessments, such as the diversity of approaches used, are often overlooked and should be better understood. OBJECTIVE: Our goal was to examine economic studies of adolescent vaccines and compare cost-effectiveness outcomes among studies on a particular vaccine, across adolescent vaccines, and between new adolescent vaccines versus vaccines that are recommended for young children. METHODS: A systematic review of economic studies on immunizations for adolescents was conducted. Studies were identified by searching the Medline, Embase, and EconLit databases. Each study was reviewed for appropriateness of model design, baseline setup, sensitivity analyses, and input variables (ie, epidemiologic, clinical, cost, and quality-of-life impact). For comparison, the cost-effectiveness outcomes reported in key studies on vaccines for younger children were selected. RESULTS: Vaccines for healthy adolescents were consistently found to be more costly than the health care or societal cost savings they produced and, in general, were less cost-effective than vaccines for younger children. Among the new vaccines, pertussis and human papillomavirus vaccines were more cost-effective than meningococcal vaccines. Including herd-immunity benefits in studies significantly improved the cost-effectiveness estimates for new vaccines. Differences in measurements or assumptions limited further comparisons. CONCLUSION: Although using the new adolescent vaccines is unlikely to be cost-saving, vaccination programs will result in sizable health benefits.