Costs and outcomes of acute kidney injury (AKI) following cardiac surgery.

BACKGROUND: Acute kidney injury (AKI) is a recognized complication of cardiac surgery; however, the variability in costs and outcomes reported are due, in part, to different criteria for diagnosing and classifying AKI. We determined costs, resource use and mortality rate of patients. We used the serum creatinine component of the RIFLE system to classify AKI. METHODS: A retrospective cohort study was conducted from the electronic data repository at the University of Pittsburgh Medical Center of patients who underwent cardiac surgery and had an elevation (>or=0.5 mg/dl) of serum creatinine postoperatively. Data were compared to age- and APACHE III-matched controls. Cost, mortality and resource use of AKI patients were determined postoperatively for each of the three RIFLE classes on the basis of changes in serum creatinine. RESULTS: Of the 3741 admissions, 258 (6.9%) had AKI and were classified as RIFLE-R 138 (3.7%), RIFLE-I 70 (1.9%) and RIFLE-F 50 (1.3%). Total and departmental level costs, length of stay (LOS) and requirement for renal replacement therapy (RRT) were higher in AKI patients compared to controls. Statistically significant differences in all costs, mortality rate and requirement for RRT were seen in the patients stratified into RIFLE-R, RIFLE-I and RIFLE-F. Even patients with the smallest change in serum creatinine, namely RIFLE-R, had a 2.2-fold greater mortality, a 1.6-fold increase in ICU LOS and 1.6-fold increase in total postoperative costs compared to controls. DISCUSSION: Costs, LOS and mortality are higher in postoperative cardiac surgery patients who develop AKI using RIFLE criteria, and these values increase as AKI severity worsens.

Quality-adjusted life years was a poor predictor of women's willingness to pay in acute and chronic conditions: results of a survey.

OBJECTIVE: We investigated the relationship between quality-adjusted life years (QALYs) and willingness to pay (WTP) in acute and chronic conditions. STUDY DESIGN AND SETTING: Face-to-face interviews were used to collect data in a convenience sample of women. Participants completed one interview evaluating preferences for an acute condition, post-chemotherapy nausea and vomiting (PCNV), and the other interview for a chronic condition (breast cancer). Preferences were elicited for QALYs using visual analogue scale (VAS), and standard gamble in addition to WTP. Because QALYs and WTP are purportedly based on the same underlying theoretical foundations, WTP was regressed onto change in QALYs, age, income, and health status. RESULTS: Regression analysis reported statistically significant models for all breast cancer (P < .001) and PCNV (P < .05) conditions tested. However, QALY was not a significant predictor of WTP. CONCLUSION: The results of this study indicate QALYs was a poor predictor of WTP for the conditions tested. Linear combinations of change in QALYs, age, income, and health status were a better predictor of WTP for chronic than acute conditions. This can be attributed to violations of underlying assumptions in measurement of QALYs with acute conditions and to problems with the use of WTP with chronic conditions.

Economic impact of asthma therapy with fluticasone propionate, montelukast, or zafirlukast in a managed care population.

STUDY OBJECTIVE: To compare asthma-related health care expenditures among patients newly prescribed fluticasone propionate 44 or 110 microg, montelukast 5 or 10 mg, or zafirlukast 20 mg. DESIGN: Retrospective cohort analysis of medical and pharmacy claims. SETTING: University-affiliated health outcomes research center. PATIENTS: Seven hundred eighty-one patients (aged > or = 4 yrs) with asthma treated with controller therapy for 9 months (postindex period), with no claim for an inhaled corticosteroid or leukotriene modifier in the previous 9 months (preindex period). INTERVENTION: Asthma-related medical and pharmacy data from insurance claims of four managed care plans (two Northeastern, one Midwestern, and one Western) were tabulated over the pre- and postindex periods. MEASUREMENTS AND MAIN RESULTS: Numbers of patients identified were 284 beginning fluticasone propionate; 302, montelukast; and 195, zafirlukast. Fluticasone propionate treatment was associated with significantly (p<0.001) lower risk-adjusted asthma-related charges compared with montelukast and zafirlukast treatment: $528, $967, and $1359, respectively In this cohort, fluticasone propionate also was associated with fewer hospitalizations, less need for additional controller agents, and longer maintenance on the index drug compared with montelukast and zafirlukast. CONCLUSIONS: Based on these real-world data, as well as established national and international asthma guidelines, consideration should be given to inhaled corticosteroid therapy, particularly fluticasone propionate, for first-line, long-term effective management of asthma.

Are health states 'timeless'? A case study of an acute condition: post-chemotherapy nausea and vomiting.

RATIONALE, AIMS AND OBJECTIVES: The objective was to test whether individuals' responses to standard gamble (SG) and visual analogue scale (VAS) questions do not depend on the time horizon of the health scenario presented. METHODS: Face-to-face interviews were conducted in a convenience sample of 18 women aged 22-50 years with no history of breast cancer or cancer requiring chemotherapy. Data were collected from March 2000 to June 2000 at a university in the Midwest of the United States of America. Preference weights were estimated using SG top-down titration method and VAS scaled from zero (death) to one (perfect health). Subjects were asked to rate their preferences if faced with two scenarios: post-chemotherapy nausea and vomiting (PCNV) occurring for 3 days (scenario 1), and PCNV lasting for the rest of their lives (scenario 2). Three PCNV health states of varying severity were tested: complete alleviation, partial alleviation, and no alleviation. RESULTS: Paired-t-test analysis showed statistically significantly lower preference weights (P < 0.05) when the health state was for the rest of the respondent's life vs. 3 days. Mean SG weights for scenario 1 vs. scenario 2 were: 0.968 vs. 0.927 (complete alleviation), 0.942 vs. 0.810 (partial alleviation) and 0.866 vs. 0.644 (no alleviation). Mean VAS weights for scenario 1 vs. scenario 2 were: 0.741 vs. 0.676 (complete alleviation), 0.490 vs. 0.307 (partial alleviation) and 0.276 vs. 0.136 (no alleviation). DISCUSSION AND CONCLUSIONS: For the majority of respondents the utility independence assumption for SG and VAS did not hold. Similar to Bala et al., the results of this study indicated that preference weights as measured by SG and VAS techniques were not 'timeless'. Regardless of the preference measure used, both SG and VAS yielded higher scores when PCNV lasted for a shorter period of time.

Perceived barriers to medical-error reporting: an exploratory investigation.

Medical-error reporting is an essential component for patient safety enhancement. Unfortunately, medical errors are largely underreported across healthcare institutions. This problem can be attributed to different factors and barriers present at organizational and individual levels that ultimately prevent individuals from generating the report. This study explored the factors that affect medical-error reporting among physicians and nurses at a large academic medical center located in the midwest United States. A nominal group session was conducted to identify the most relevant factors that act as barriers for error reporting. These factors were then used to design a questionnaire that explored the likelihood of the factors to act as barriers and their likelihood to be modified. Using these two parameters, the results were analyzed and combined into a Factor Relevance Matrix. The matrix identifies the factors for which immediate actions should be undertaken to improve medical-error reporting (immediate action factors). It also identifies factors that require long-term strategies (long-term strategy factors) as well as factors that the organization should be aware of but that are of lower priority (awareness factors). The strategies outlined in this study may assist healthcare organizations in improving medical-error reporting, as part of the efforts toward patient-safety enhancement. Although factors affecting medical-error reporting may vary between different organizations, the process used in identifying the factors and the Factor Relevance Matrix developed in this study are easily adaptable to any organizational setting.

Functional Assessment in Migraine (FAIM) questionnaire: development of an instrument based upon the WHO's International Classification of Functioning, Disability, and Health.

OBJECTIVE: The goal of this project was to develop a migraine functional measurement instrument, derived from the World Health Organization International Classification of Impairments, Disabilities, and Handicaps version 2 classification system, which focuses on functional outcomes, and is both reliable and valid. METHODS: The Functional Assessment in Migraine (FAIM) questionnaire was developed using a multistep approach to ensure the brevity, relevance, reliability, and validity of items. A test set of 71 Mental Functioning and 50 Activity and Participation items was generated and administered to migraineurs in the United States and Germany. A subset of 22 Mental Functioning and 28 Activity and Participation items that rated highly on frequency-weighted importance and showed strong psychometric properties was piloted to determine a final item set and to test reliability and validity. RESULTS: The final version of the FAIM included nine Mental Functioning items measuring the dimensions of Attention/Thought (5 items) and Perception (4 items), and a list of 28 Activity and Participation items from which respondents chose the five items most relevant to their lifestyle. Construct validity analysis of FAIM dimensions found significant positive correlations with self-reported symptom severity, moderately significant positive correlations with dimensions of the Migraine-Specific Quality of Life questionnaire and no significant correlation with Short Form Health Survey (SF-12) component scores. CONCLUSION: The FAIM offers physicians a brief and valid method of measuring the impact of migraine on mental functioning and activity and participation as defined by the WHO International Classification of Functioning, Disability, and Health. Additional testing is underway to assess its responsiveness to change.

Are the Naranjo criteria reliable and valid for determination of adverse drug reactions in the intensive care unit?

BACKGROUND: The Naranjo criteria are frequently used for determination of causality for suspected adverse drug reactions (ADRs); however, the psychometric properties have not been studied in the critically ill. OBJECTIVE: To evaluate the reliability and validity of the Naranjo criteria for ADR determination in the intensive care unit (ICU). METHODS: All patients admitted to a surgical ICU during a 3-month period were enrolled. Four raters independently reviewed 142 suspected ADRs using the Naranjo criteria (review 1). Raters evaluated the 142 suspected ADRs 3-4 weeks later, again using the Naranjo criteria (review 2). Inter-rater reliability was tested using the kappa statistic. The weighted kappa statistic was calculated between reviews 1 and 2 for the intra-rater reliability of each rater. Cronbach alpha was computed to assess the inter-item consistency correlation. The Naranjo criteria were compared with expert opinion for criterion validity for each rater and reported as a Spearman rank (r(s)) coefficient. RESULTS: The kappa statistic ranged from 0.14 to 0.33, reflecting poor inter-rater agreement. The weighted kappa within raters was 0.5402-0.9371. The Cronbach alpha ranged from 0.443 to 0.660, which is considered moderate to good. The r(s) coefficient range was 0.385-0.545; all r(s) coefficients were statistically significant (p < 0.05). CONCLUSIONS: Inter-rater reliability is marginal; however, within-rater evaluation appears to be consistent. The inter-item correlation is expected to be higher since all questions pertain to ADRs. Overall, the Naranjo criteria need modification for use in the ICU to improve reliability, validity, and clinical usefulness.

Effect of including (versus excluding) fates worse than death on utility measurement.

OBJECTIVES: Most studies typically measure health preferences excluding health states perceived as worse than death. The objective of this study is to test the impact of including (versus excluding) health states perceived to be worse than death on utility measurement using standard gamble (SG) and visual analogue scale (VAS) methods. METHODS: By means of a cross-sectional descriptive study design, women were asked to rate the utility of three hypothetical breast cancer health states: cure, treatment, and recurrence (n=119). Preference weights were estimated, allowing for negative utilities with death (perfect health) scaled at zero (1.0). RESULTS: Unpaired t-test analysis showed significantly greater change in SG and VAS weights for individuals perceiving cancer recurrence as worse than death than those perceiving death as least desirable state. Excluding negative utilities from the study resulted in significantly smaller changes in utility. Study results show that preference elicitation methods can be successfully adapted to acquire negative utilities. CONCLUSIONS: Changes in utility were greater when negative preferences were permitted. Addressing negative preference scores could significantly affect quality adjusted life year estimates in economic analyses.

Assessment of respondent acceptability of preference measures: discriminatory power of graphic positioning scale versus traditional scaling measures.

OBJECTIVE: The objective of this study was to compare discriminatory power of two different measures-graphic positioning scale (GPS) versus traditional scale (TS)-in assessing respondent acceptability of three preference measures: visual analog scale (VAS), standard gamble (SG), and willingness to pay (WTP). METHODS: Two face-to-face interviews were conducted at least 1 week apart in a convenience sample of women aged 22 to 50 years with no history of breast cancer or cancer requiring chemotherapy. Study participation required completion of two surveys: one evaluating health preferences for an acute condition (chemotherapy-induced nausea and vomiting) and one evaluating a chronic condition (breast cancer). Data were collected from March 2000 to June 2000 at Ohio State University. Respondents were randomized to either GPS or TS surveys. Data analysis was a two-step process. First, a four-way multivariate repeated-measures analysis of variance (MANOVA) was conducted to assess respondent acceptability of three-preference metrics-VAS, SG, and WTP-in health-care decision making. Each of the four dependent variables, difficulty, clarity, reasonableness, and comfort in use in decision making, was measured on 9-point Likert scale. Second, a mixed design univariate analysis of variance (ANOVA) was performed for each dependent variable to optimize MANOVA analysis. Univariate ANOVAs, 2 x (2 x 3), were composed of three independent variables: assessment (GPS/TS), condition (acute and chronic), and preferences (VAS, SG, WTP). RESULTS: Of 126 respondents, 119 were usable and complete. MANOVA results showed (P <.05) for two main effects, condition (F4,114 = 6.375) and preferences (F8,110 = 9.290), and two significant interactions, condition x assessment (F4,114 = 3.421) and condition x preferences (F8,110 = 2.087). CONCLUSION: GPS has higher discriminatory power than TS in assessing respondent attitudes toward health preference measures. Results showed that respondents had more difficulty and less comfort when making decisions for chronic than for acute conditions. Results also show that respondents regard WTP as a more reasonable decision-making tool when assessing acute interventions in preference to SG and vice versa for chronic conditions. Of VAS, SG, and WTP methods, VAS was perceived as being the easiest to understand. These results can be explained by direct versus indirect comparisons made with GPS and TS methods, respectively.