Alabama coronary artery bypass grafting project: results of a statewide quality improvement initiative.

CONTEXT: Efforts to improve quality of care in the cardiac surgery field have focused on reducing the risk-adjusted mortality associated with common surgical procedures, such as coronary artery bypass grafting (CABG). However, the best methodological approach to improvement is under debate. OBJECTIVE: To test an intervention to improve performance of CABG surgery. DESIGN AND SETTING: Quality improvement project based on baseline (July 1, 1995-June 30, 1996) and follow-up (July 1-December 31, 1998) performance measurements from medical record review for all 20 Alabama hospitals that provided CABG surgery. PATIENTS: Medicare patients discharged after CABG surgery in Alabama (n = 5784), a comparison state (n = 3214), and a national sample (n = 3758). INTERVENTION: Confidential hospital-specific performance feedback and assistance with multimodal improvement interventions, including the option to share relevant experience with peers. MAIN OUTCOME MEASURES: Duration of intubation, reintubation rate, aspirin therapy at discharge, use of the internal mammary artery (IMA), hospital readmission rate, and risk-adjusted in-hospital mortality. RESULTS: Proportion of extubation within 6 hours increased from 9% to 41% in Alabama, decreased from 40% to 39% in the comparison state, and increased from 12% to 25% in the national sample. Use of IMA increased from 73% to 84%, 48% to 55%, and 74% to 81%, respectively, in the 3 samples, but aspirin use increased only in Alabama (from 88% to 92%). The amount of improvement in all 3 of these process measures was greater in Alabama than in the other samples (IMA use for Alabama vs comparison state was P =.001 and for Alabama vs national sample, P =.02; and P<.001 for all other comparisons). Risk-adjusted mortality decreased in Alabama (4.9% to 2.9%), but this decrease was not statistically significantly different from mortality changes in the other groups (odds ratio, 0.76; 95% confidence interval, 0.54-1.07 vs national sample). CONCLUSION: Confidential peer-based regional performance feedback and process-oriented analysis of shared experience are associated with some improvement in quality of care for patients who underwent CABG surgery.

Sagittal diameter in comparison with single slice CT as a predictor of total visceral adipose tissue volume.

BACKGROUND: Abdominal obesity has an important biological and epidemiological relationship to disease. The gold standard for measurement of visceral adipose tissue (VAT) is assessment by computerized tomography (CT) or magnetic resonance imaging (MRI), but because of simplicity and ease in collection, anthropometric variables are a desirable alternative to estimate VAT. OBJECTIVE: To compare the abilities of a single slice CT scan through the L4-L5 interspace (L4-L5 VAT), sagittal diameter, and body mass index (BMI) to estimate total volume VAT. Total volume VAT (the gold standard) was measured by total abdominal CT scanning, with a mean of 42 CT slices per patient. Estimation of VAT in subjects of similar body size was emphasized. DESIGN: Retrospective study of subjects undergoing complete abdominal and pelvic CT scanning for clinical reasons. SUBJECTS: 40 subjects (20 men and 20 women) mean age 56.5y, with a balanced selection for BMI < 27 and > 27. RESULTS: In univariate regression models, L4-L5 VAT explained the largest proportion of the variance in total VAT (R2=0.87 [P<0.001]), though age (R2=0.11 [P=0.04]), BMI (R2=0.37 [P<0.001]), and sagittal diameter (R2=0.50 [P < 0.001]) were also statistically significantly related to total VAT. When limited to individuals with a BMI > or= 27 however, L4-L5 VAT explained a large proportion of the variance in total VAT (R2=0.87 [P < 0.001]) whereas sagittal diameter was only of borderline significance (R2=0.20 [P=0.06]), and BMI was not associated with total VAT (R2=0.04 [P=NS]). In multiple regression analyses, L4-L5 VAT area explained a large proportion of the variance (0.84-0.90), and once in the model, BMI, sagittal diameter, and age did not additionally contribute significantly to the explained variance in total VAT. CONCLUSIONS: Abdominal sagittal diameter is poorly correlated to total VAT for men and women with a BMI > 27. Within a 2 cm range of sagittal diameter, there is nearly a three-fold variability in total VAT.

Effect of sample storage on quantitation of lipoprotein(a) by an enzyme-linked immunosorbent assay.

This study evaluated the effect of storage on the quantitation of lipoprotein (Lp)(a) in 25 serum samples. Aliquots of serum were stored for up to three years at either -20 degrees C or -70 degrees C and Lp(a) subsequently analyzed using an enzyme-linked immunosorbent assay kit. Concentrations of Lp(a) declined during storage, and the temperatures employed elicited significantly different (P < 0.05) values within 12 mon which further diverged during three years of storage. Compared to baseline values, significant decreases (P < 0.05) in Lp(a) levels were evident after six months of storage at -20 degrees C with apparent losses (geometric mean) reaching 36.9% (95% confidence interval: 30.9%, 42.9%) after three years. Similarly, significantly lower (P < 0.05) Lp(a) values were recorded after six months of storage at -70 degrees C and at three years the decrease (geometric mean) was 19.1% (95% confidence interval: 14.3%, 24.0%). The losses, after three years, in terms of the arithmetic mean were 53.5 and 26.2% at -20 and -70 degrees C, respectively. Phenotype analysis suggested that large isoforms are more susceptible to degradation than smaller moieties. This may be related to the observation that apparent losses are reduced in samples containing over 8 mg/dL Lp(a). Nevertheless, Lp(a) levels in stored samples retained a strong correlation with the baseline values. These results must be considered specific for the storage conditions and analytical procedures employed.

Hospitalized pneumonia. Outcomes, treatment patterns, and costs in urban and rural areas.

OBJECTIVES: To describe discharge rates, geographic and patient characteristics, treatment patterns, costs, and outcomes of patients hospitalized with community-acquired pneumonia (CAP) in Pennsylvania hospitals and compare these patients from rural and urban counties. DESIGN: A retrospective database study. PATIENTS: Adult patients (age > or = 18) with an ICD-9-CM diagnosis of pneumonia discharged from 193 Pennsylvania hospitals (n = 36,222) in 1991 from the MediQual Systems Pennsylvania database. MEASUREMENTS: Patient characteristics included a pneumonia-specific severity index, microbiologic etiology, and a number of comorbid conditions. Treatment indicators included the specialty of the admitting physician, length of stay, admittance to an intensive care unit, and mechanical ventilation. Cost indicators included charges and estimated costs. Outcomes measured were inpatient mortality and discharge disposition. Counties in Pennsylvania were classified into seven urban or rural groups, and patients were classified by the county of residence. RESULTS: The discharge rate for CAP was 4.0 per 1,000 and did not vary systematically across urban or rural counties. Most patients were treated in local hospitals. The average distance between residence and hospital was 5.4 miles and varied with urban or rural classification (range 2.5-9.3 miles). Among CAP patients, 37.8% were at low risk of mortality, with no systematic differences across rural or urban patients with respect to pneumonia severity. Rural patients were more likely to be treated by a family physician and somewhat less likely to be admitted to an intensive care unit or to be mechanically ventilated. Costs of treating rural patients were lower. In-hospital mortality rates, with controls for admission severity, were comparable or better for rural patients than for urban patients. CONCLUSIONS: Patients with CAP are treated in hospitals located in counties similar to ones in which they reside. The cost of treatment was lower for rural patients than for urban patients, but outcomes were not different.

Does visceral adipose tissue differ from subcutaneous adipose tissue in fatty acid content?

OBJECTIVE: To determine whether intra-abdominal adipose tissue differs from subcutaneous adipose tissue in fatty acid content. DESIGN: Cross-sectional study of patients undergoing exploratory laparotomy, with adipose tissue sampling from subcutaneous, omental, mesenteric and retroperitoneal sites. SUBJECTS: Nineteen subjects, 8 men and 11 women, with a mean age of 64 (range 39-80), mean weight 78.9 kg (range 51-157) and mean body mass index of 27.5 (range 19.2-51.4). Fourteen of the 19 were undergoing surgery for colorectal cancer. MEASUREMENTS: Fatty acid content was assessed by gas chromatography and was compared between sites and between patients using general linear modeling. Spearman correlation coefficients were used to assess the association between subcutaneous and visceral adipose tissue. RESULTS: For each of 17 fatty acids analyzed, there was a statistically significant difference in mean fatty acid values across individuals (p < 0.001). For seven of the fatty acids, there was a borderline or significant difference in mean fatty acid values across site, but there was no consistent pattern for one site differing from the others. Subcutaneous adipose tissue fatty acid content was highly correlated to visceral adipose tissue for saturated, unsaturated and trans fatty acids (p < 0.05 for 13 of 17 fatty acids). Variability across individuals was much greater than across site. The total explained variability (R2) for each fatty acid ranged between 49 and 93%, with the vast majority contributed by differences between individuals. CONCLUSION. Fatty acid content of subcutaneous abdominal adipose tissue is a good approximation of visceral adipose tissue. Because variability in fatty acid content is much larger between individuals than within a single individual across sites, subcutaneous abdominal adipose tissue fatty acid content can be used as a distinguishing characteristic among human populations.

Prognosis and outcomes of patients with community-acquired pneumonia. A meta-analysis.

OBJECTIVE: To systematically review the medical literature on the prognosis and outcomes of patients with community-acquired pneumonia (CAP). DATA SOURCES: A MEDLINE literature search of English-language articles involving human subjects and manual reviews of article bibliographies were used to identify studies of prognosis in CAP. STUDY SELECTION: Review of 4573 citations revealed 122 articles (127 unique study cohorts) that reported medical outcomes in adults with CAP. DATA EXTRACTION: Qualitative assessments of studies' patient populations, designs, and patient outcomes were performed. Summary univariate odds ratios (ORs) and rate differences (RDs) and their associated 95% confidence intervals (CIs) were computed to estimate a summary effect size for the association of prognostic factors and mortality. DATA SYNTHESIS: The overall mortality for the 33,148 patients in all 127 study cohorts was 13.7%, ranging from 5.1% for the 2097 hospitalized and ambulatory patients (in six study cohorts) to 36.5% for the 788 intensive care unit patients (in 13 cohorts). Mortality varied by pneumonia etiology, ranging from less than 2% to greater than 30%. Eleven prognostic factors were significantly associated with mortality using both summary ORs and RDs: male sex (OR = 1.3; 95% CI, 1.2 to 1.4), pleuritic chest pain (OR = 0.5; 95% CI, 0.3 to 0.8), hypothermia (OR = 5.0; 95% CI, 2.4 to 10.4), systolic hypotension (OR = 4.8; 95% CI, 2.8 to 8.3), tachypnea (OR = 2.9; 95% CI, 1.7 to 4.9), diabetes mellitus (OR = 1.3; 95% CI, 1.1 to 1.5), neoplastic disease (OR = 2.8; 95% CI, 2.4 to 3.1), neurologic disease (OR = 4.6; 95% CI, 2.3 to 8.9), bacteremia (OR = 2.8; 95% CI, 2.3 to 3.6), leukopenia (OR = 2.5, 95% CI, 1.6 to 3.7), and multilobar radiographic pulmonary infiltrate (OR = 3.1; 95% CI, 1.9 to 5.1). Assessments of other clinically relevant medical outcomes such as morbid complications (41 cohorts), symptoms resolution (seven cohorts), return to work or usual activities (five cohorts), or functional status (one cohort) were infrequently performed. CONCLUSIONS: Mortality for patients hospitalized with CAP was high and was associated with characteristics of the study cohort, pneumonia etiology, and a variety of prognostic factors. Generalization of these findings to all patients with CAP should be made with caution because of insufficient published information on medical outcomes other than mortality in ambulatory patients.

Efficacy of pneumococcal vaccination in adults. A meta-analysis of randomized controlled trials.

BACKGROUND: Because of the prevalence of pneumococcal pneumonia, the substantial morbidity and mortality associated with many pneumococcal infections, and an increase in the incidence of antibiotic resistance among pneumococcal isolates, considerable efforts for disease prevention have been made using a polyvalent polysaccharide pneumococcal vaccine. Despite numerous clinical trials of the vaccine, its efficacy in the prevention of pneumococcal infections and other clinically relevant medical outcomes in adults remains uncertain. METHODS: To assess quantitatively the efficacy of pneumococcal vaccination, a MEDLINE literature search, manual reviews of article bibliographies, and communications with pneumococcal vaccine investigators were used to identify randomized controlled trials of the pneumococcal vaccine. Independent review of 594 articles revealed nine randomized trials with 12 vaccine and control study groups that evaluated clinically relevant outcomes in adults. To estimate a summary effect size for all outcomes, Mantel-Haenszel odds ratios (ORs) and Dersimonian and Laird rate differences (RDs) and their associated 95% confidence intervals (CIs) were computed. RESULTS: Summary ORs demonstrated a statistically significant protective effect of the vaccine for four pneumococcal infection-related outcomes: definitive pneumococcal pneumonia (OR = 0.34; 95% CI = 0.24 to 0.48), definitive pneumococcal pneumonia for vaccine-containing pneumococcal antigen types only (vaccine types only) (OR = 0.17; 95% CI = 0.09 to 0.33), presumptive pneumococcal pneumonia (OR = 0.47; 95% CI = 0.35 to 0.63), and presumptive pneumococcal pneumonia (vaccine types only) (OR = 0.39; 95% CI = 0.26 to 0.59). The summary RDs, which account for heterogeneity among studies, confirmed a statistically significant protective effect for two of these same outcomes: definitive pneumococcal pneumonia (RD = 4/1000; 95% CI = 0/1000 to 7/1000) and definitive pneumococcal pneumonia (vaccine types only) (RD = 8/1000; 95% CI = 1/1000 to 16/1000). Summary ORs and RDs failed to demonstrate a protective effect for pneumonia (all causes), bronchitis, and mortality (all causes) or mortality due to pneumonia or pneumococcal infection. Subgroup analyses showed that for all four pneumococcal infection-related outcomes, vaccine efficacy differed for high- and low-risk subjects, demonstrating efficacy for low-risk subjects and lack of efficacy for high-risk subjects. CONCLUSIONS: Pneumococcal vaccination appears efficacious in reducing bacteremic pneumococcal pneumonia in low-risk adults. However, evidence from randomized controlled trials fails to demonstrate vaccine efficacy for pneumococcal infection-related or other medical outcomes in the heterogeneous group of subjects currently labeled as high risk.