Arterial blood gas and pulse oximetry in initial management of patients with community-acquired pneumonia.

OBJECTIVE: To identify the factors associated with the use of arterial blood gas (ABG) and pulse oximetry (PO) in the initial management of patients with community-acquired pneumonia (CAP) and arterial hypoxemia at presentation. PARTICIPANTS: A total of 944 outpatients and 1,332 inpatients with clinical and radiographic evidence of CAP prospectively enrolled from 5 study sites in the United States and Canada. ANALYSES: Separate multivariate logistic regression analyses were used to 1) compare measurement of ABG and PO within 48 hours of presentation across sites while controlling for patient differences, and 2) identify factors associated with arterial hypoxemia (PaO2 <60 mm Hg or SaO2 <90% for non-African Americans and <92% for African Americans) while breathing room air. RESULTS: Range of ABG use by site was from 0% to 6.4% (P =.06) for outpatients and from 49.2% to 77.3% for inpatients (P <.001), while PO use ranged from 9.4% to 57.8% for outpatients (P <.001) and from 47.9% to 85.1% for inpatients (P <.001). Differences among sites remained after controlling for patient demographic characteristics, comorbidity, and illness severity. In patients with 1 or more measurements of oxygenation at presentation, hypoxemia was independently associated with 6 risk factors: age >30 years (odds ratio [OR], 3.2; 95% confidence interval [CI], 1.7 to 5.9), chronic obstructive pulmonary disease (OR, 1.9; 95% CI, 1.4 to 2.6), congestive heart failure (OR, 1.5; 95% CI, 1.0 to 2.1), respiratory rate >24 per minute (OR, 2.3; 95% CI, 1.8 to 3.0), altered mental status (OR, 1.6; 95% CI, 1.1 to 2.3), and chest radiographic infiltrate involving >1 lobe (OR, 2.2; 95% CI, 1.7 to 2.9). The prevalence of hypoxemia among those tested ranged from 13% for inpatients with no risk factors to 54.6% for inpatients with > or =3 risk factors. Of the 210 outpatients who had > or =2 of these risk factors, only 64 (30.5%) had either an ABG or PO performed. In the 48 outpatients tested without supplemental O2 with > or =2 risk factors 8.3% were hypoxemic. CONCLUSIONS: In the initial management of CAP, use of ABG and PO varied widely across sites. Increasing the assessment of arterial oxygenation among patients with CAP is likely to increase the detection of arterial hypoxemia, particularly among outpatients.

Relation between length of hospital stay and costs of care for patients with community-acquired pneumonia.

PURPOSE: Patients with pneumonia often remain hospitalized after becoming clinically stable, without demonstrated benefits on outcome. The purposes of this study were to assess the relation between length of hospital stay and daily medical care costs and to estimate the potential cost savings associated with a reduced length of stay for patients with pneumonia. SUBJECTS AND METHODS: As part of a prospective study of adults hospitalized with community-acquired pneumonia at a community hospital and two university teaching hospitals, daily medical care costs were estimated by multiplying individual charges by department-specific cost-to-charge ratios obtained from each hospital's Medicare cost reports. RESULTS: The median total cost of hospitalization for all 982 inpatients was $5, 942, with a median daily cost of $836, including $491 (59%) for room and $345 (41%) for non-room costs. Average daily non-room costs were 282% greater on the first hospital day, 59% greater on the second day, and 19% greater on the third day than the average daily cost throughout the hospitalization (all P <0.05), and were 14% to 72% lower on the last 3 days of hospitalization. Average daily room costs remained relatively constant throughout the hospital stay, with the exception of the day of discharge. A projected mean savings of $680 was associated with a 1-day reduction in length of stay. CONCLUSIONS: Despite institutional differences in total costs, patterns of daily resource use throughout hospitalization were similar at all institutions. A 1-day reduction in length of stay might yield substantial cost-savings.

Clinical presentation, processes and outcomes of care for patients with pneumococcal pneumonia.

OBJECTIVE: To describe the presentation, resolution of symptoms, processes of care, and outcomes of pneumococcal pneumonia, and to compare features of the bacteremic and nonbacteremic forms of this illness. DESIGN: A prospective cohort study. SETTING: Five medical institutions in 3 geographic locations. PARTICIPANTS: Inpatients and outpatients with community-acquired pneumonia (CAP). MEASUREMENTS: Sociodemographic characteristics, respiratory and nonrespiratory symptoms, and physical examination findings were obtained from interviews or chart review. Severity of illness was assessed using a validated prediction rule for short-term mortality in CAP. Pneumococcal pneumonia was categorized as bacteremic; nonbacteremic, pure etiology; or nonbacteremic, mixed etiology. MAIN RESULTS: One hundred fifty-eight (6.9%) of 2,287 patients (944 outpatients, 1,343 inpatients) with CAP had pneumococcal pneumonia. Sixty-five (41%) of the 158 with pneumococcal pneumonia were bacteremic; 74 (47%) were nonbacteremic with S. pneumoniae as sole pathogen; and 19 (12%) were nonbacteremic with S. pneumoniae as one of multiple pathogens. The pneumococcal bacteremia rate for outpatients was 2.6% and for inpatients it was 6.6%. Cough, dyspnea, and pleuritic pain were common respiratory symptoms. Hemoptysis occurred in 16% to 22% of the patients. A large number of nonrespiratory symptoms were noted. Bacteremic patients were less likely than nonbacteremic patients to have sputum production and myalgias (60% vs 82% and 33% vs 57%, respectively; P <.01 for both), more likely to have elevated blood urea nitrogen and serum creatinine levels, and more likely to receive penicillin therapy. Half of bacteremic patients were in the low risk category for short-term mortality (groups I to III), similar to the nonbacteremic patients. None of the 32 bacteremic patients in risk groups I to III died, while 7 of 23 (30%) in risk group V died. Intensive care unit admissions and pneumonia-related mortality were similar between bacteremic and nonbacteremic groups, although 46% of the bacteremic group had respiratory failure compared with 32% and 37% for the other groups. The nonbacteremic pure etiology patients returned to household activities faster than bacteremic patients. Symptoms frequently persisted at 30 days: cough (50%); dyspnea (53%); sputum production (48%); pleuritic pain (13%); and fatigue (63%). CONCLUSIONS: There were few differences in the presentation of bacteremic and nonbacteremic pneumococcal pneumonia. About half of bacteremic pneumococcal pneumonia patients were at low risk for mortality. Symptom resolution frequently was slow.

Variation in length of hospital stay in patients with community-acquired pneumonia: are shorter stays associated with worse medical outcomes?

PURPOSE: To assess the variation in length of stay for patients hospitalized with community-acquired pneumonia and to determine whether patients who are treated in hospitals with shorter mean stays have worse medical outcomes. SUBJECTS AND METHODS: We prospectively studied a cohort of 1,188 adult patients with community-acquired pneumonia who had been admitted to one community and three university teaching hospitals. We compared patients' mean length of stay, mortality, hospital readmission, return to usual activities, return to work, and pneumonia-related symptoms among the four study hospitals. All outcomes were adjusted for baseline differences in severity of illness and comorbidity. RESULTS: Adjusted interhospital differences in mean length of stay ranged from 0.9 to 2.3 days (P <0.001). When the risk of each medical outcome was compared between patients admitted to the hospital with the shortest length of stay and those admitted to longer stay hospitals, there were no differences in mortality [relative risk (RR) = 0.7; 95% CI, 0.3 to 1.7], hospital readmission (RR = 0.8; 95% CI, 0.5 to 1.2), return to usual activities (RR = 1.1; 95% CI, 0.9 to 1.3), or return to work (RR = 1.2; 95% CI, 0.8 to 2.0) during the first 14 days after discharge, or in the mean number of pneumonia-related symptoms 30 days after admission (P = 0.54). CONCLUSIONS: We observed substantial interhospital variation in the lengths of stay for patients hospitalized with community-acquired pneumonia. The finding that medical outcomes were similar in patients admitted to the hospital with the shortest length of stay and those admitted to hospitals with longer mean lengths of stay suggests that hospitals with longer stays may be able to reduce the mean duration of hospitalization for this disease without adversely affecting patient outcomes.

Processes and outcomes of care for patients with community-acquired pneumonia: results from the Pneumonia Patient Outcomes Research Team (PORT) cohort study.

BACKGROUND: Although understanding the processes of care and medical outcomes for patients with community-acquired pneumonia is instrumental to improving the quality and cost-effectiveness of care for this illness, limited information is available on how physicians manage patients with this illness or on medical outcomes other than short-term mortality. OBJECTIVES: To describe the processes of care and to assess a broad range of medical outcomes for ambulatory and hospitalized patients with community-acquired pneumonia. METHODS: This prospective, observational study was conducted at 4 hospitals and 1 health maintenance organization in Pittsburgh, Pa, Boston, Mass, and Halifax, Nova Scotia. Data were collected via patient interviews and reviews of medical records for 944 outpatients and 1343 inpatients with clinical and radiographic evidence of community-acquired pneumonia. Processes of care and medical outcomes were assessed 30 days after presentation. RESULTS: Only 29.7% of outpatients had 1 or more microbiologic tests performed, and only 5.7% had an assigned microbiologic cause. Although 95.7% of inpatients had 1 or more microbiologic tests performed, a cause was established in only 29.6%. Six outpatients (0.6%) died, and 3 of these deaths were pneumonia related. Of surviving outpatients, 8.0% had 1 or more medical complications. At 30 days, 88.9% (nonemployed) to 95.6% (employed) of the surviving outpatients had returned to usual activities, yet 76.0% of outpatients had 1 or more persisting pneumonia-related symptoms. Overall, 107 inpatients (8.0%) died, and 81 of these deaths were pneumonia related. Most surviving inpatients (69.0%) had 1 or more medical complications. At 30 days, 57.3% (non-employed) to 82.0% (employed) of surviving inpatients had returned to usual activities, and 86.1% had 1 or more persisting pneumonia-related symptoms. CONCLUSIONS: In this study, conducted primarily at hospital sites with affiliated medical education training programs, virtually all outpatients and most inpatients had pneumonia of unknown cause. Although outpatients had an excellent prognosis, pneumonia-related symptoms often persisted at 30 days. Inpatients had substantial mortality, morbidity, and pneumonia-related symptoms at 30 days.

Time to clinical stability in patients hospitalized with community-acquired pneumonia: implications for practice guidelines.

CONTEXT: Many groups have developed guidelines to shorten hospital length of stay in pneumonia in order to decrease costs, but the length of time until a patient hospitalized with pneumonia becomes clinically stable has not been established. OBJECTIVE: To describe the time to resolution of abnormalities in vital signs, ability to eat, and mental status in patients with community-acquired pneumonia and assess clinical outcomes after achieving stability. DESIGN: Prospective, multicenter, observational cohort study. SETTING: Three university and 1 community teaching hospital in Boston, Mass, Pittsburgh, Pa, and Halifax, Nova Scotia. PATIENTS: Six hundred eighty-six adults hospitalized with community-acquired pneumonia. MAIN OUTCOME MEASURES: Time to resolution of vital signs, ability to eat, mental status, hospital length of stay, and admission to an intensive care, coronary care, or telemetry unit. RESULTS: The median time to stability was 2 days for heart rate (< or =100 beats/min) and systolic blood pressure (> or =90 mm Hg), and 3 days for respiratory rate (< or =24 breaths/min), oxygen saturation (> or =90%), and temperature (< or =37.2 degrees C [99 degrees F]). The median time to overall clinical stability was 3 days for the most lenient definition of stability and 7 days for the most conservative definition. Patients with more severe cases of pneumonia at presentation took longer to reach stability. Once stability was achieved, clinical deterioration requiring intensive care, coronary care, or telemetry monitoring occurred in 1% of cases or fewer. Between 65% to 86% of patients stayed in the hospital more than 1 day after reaching stability, and fewer than 29% to 46% were converted to oral antibiotics within 1 day of stability, depending on the definition of stability. CONCLUSIONS: Our estimates of time to stability in pneumonia and explicit criteria for defining stability can provide an evidence-based estimate of optimal length of stay, and outline a clinically sensible approach to improving the efficiency of inpatient management.

Variations in antimicrobial use and cost in more than 2,000 patients with community-acquired pneumonia.

PURPOSE: To assess the patterns of antimicrobial use, costs of antimicrobial therapy, and medical outcomes by institution in patients with community-acquired pneumonia. PATIENTS AND METHODS: The route, dose, and frequency of administration of all antimicrobial agents prescribed within 30 days of presentation were recorded for 927 outpatients and 1328 inpatients enrolled in the Pneumonia Patient Outcomes Research Team (PORT) multicenter, prospective cohort study. Total antimicrobial costs were estimated by summing drug costs, using average wholesale price for oral agents and institutional acquisition prices for parenteral agents, plus the costs associated with preparation and administration of parenteral therapy. Thirty-day outcome measures were mortality, subsequent hospitalization for outpatients, and hospital readmission for inpatients. RESULTS: Significant variation (P <0.05) in prescribing practices occurred for 17 of the 23 antimicrobial agents used in outpatients across 5 treatment sites, and for 18 of the 20 parenteral agents used in inpatients across 4 treatment sites. The median duration of antimicrobial therapy for treatment site ranged from 11 to 13 days for outpatients (P=0.01), and from 13 to 15 days for inpatients (P=0.49). The overall median cost of antimicrobial therapy was $12.90 for outpatients, and ranged from $10.80 to $58.90 among treatment sites (P <0.0001). The overall median cost of antimicrobial therapy was $228.70 for inpatients, and ranged from $183.70 to $315.60 among sites (P <0.0001). Mortality and hospital readmission for inpatients were not significantly different across sites after adjusting for baseline differences in patient demographic characteristics, comorbidity, and illness severity. Although subsequent hospitalization for outpatients differed by site, the rate was lowest for the site with the lowest antimicrobial costs. CONCLUSION: Variations in antimicrobial prescribing practices by treatment site exist for outpatients and inpatients with community-acquired pneumonia. Although variation in antimicrobial prescribing practices across institutions results in significant differences in antimicrobial costs, patients treated at institutions with the lowest antimicrobial costs do not demonstrate worse medical outcomes.

Patients hospitalized after initial outpatient treatment for community-acquired pneumonia.

STUDY OBJECTIVE: To determine the incidence, causes, and outcomes of patients hospitalized within 30 days of initiating outpatient treatment for community-acquired pneumonia (CAP). DESIGN: Patients were enrolled in the Pneumonia Patient Outcomes Research Team's multicenter, prospective cohort study of CAP. All hospitalizations within 30 days of study enrollment of patients initially treated as outpatients for CAP were recorded. Two physicians used a set of predetermined definitions to independently categorize the reasons for these subsequent hospitalizations. Thirty-day mortality rate and measures of resolution of pneumonia were assessed. The setting included three university teaching hospitals, a community teaching hospital, and a staff model medical practice within a health maintenance organization. RESULTS: Of the 944 enrollees with CAP initially treated in the outpatient setting, 71 (7.5%) were subsequently hospitalized within 30 days. The reason for subsequent hospitalization was CAP related in 40 patients and comorbidity related in 26 patients; 5 refused an initial offer of hospitalization. Ninety percent of pneumonia-related hospitalizations occurred within 10 days of initial presentation. Patients who were subsequently hospitalized required a median of 14 days to return to usual activities compared with 6 days for those who were not hospitalized (P<.0001). Patients with a subsequent hospitalization had a higher 30-day mortality rate, 4.2% compared with .3% (P<.01). CONCLUSION: A small proportion of patients with CAP initially treated in the outpatient setting are subsequently hospitalized. Such patients face a higher risk of delayed recovery or death. However, the vast majority of outpatients, whether subsequently hospitalized or not, had a successful resolution of their illness. Subsequent hospitalization by 10 days after initial outpatient treatment seems a reasonable screening tool for potentially unsatisfactory quality of care for patients with CAP.

Influence of age on symptoms at presentation in patients with community-acquired pneumonia.

BACKGROUND: Advanced age has become a well-recognized risk factor for death in patients with pneumonia. It may also be associated with reduced symptom reporting, raising the possibility that diagnosis and treatment may be delayed in older patients. OBJECTIVE: To evaluate the association between age and the presenting symptoms in patients with community-acquired pneumonia. METHODS: This study was conducted at inpatient and outpatient facilities at 3 university hospitals, 1 community hospital, and 1 staff-model health maintenance organization. Patients included adults (age > or = 18 years) with clinical and radiographic evidence of pneumonia, who were able to complete a baseline interview. The presence of 5 respiratory symptoms and 13 nonrespiratory symptoms were recorded during a baseline patient interview. A summary symptom score was computed as the total number of symptoms at presentation. RESULTS: The 1812 eligible study patients were categorized into 4 age groups: 18 through 44 years (43%), 45 through 64 years (25%), 65 through 74 years (17%), and 75 years or older (15%). For 17 of the 18 symptoms, there were significant decreases in reported prevalence with increasing age (P < .01). In a linear regression analysis, controlling for patient demographics, comorbidity, and severity of illness at presentation, older age remained associated with lower symptom scores (P < .001). CONCLUSIONS: Respiratory and nonrespiratory symptoms are less commonly reported by older patients with pneumonia, even after controlling for the increased comorbidity and illness severity in these older patients. Recognition of this phenomenon by clinicians and patients is essential given the increased mortality in elderly patients with pneumonia.

Measuring symptomatic and functional recovery in patients with community-acquired pneumonia.

OBJECTIVE: To determine the rates of resolution of symptoms and return to premorbid health status and assess the association of these outcomes with health care utilization in patients with community-acquired pneumonia. DESIGN: A prospective, multicenter cohort study. SETTING: Inpatient and outpatient facilities at three university hospitals, one community hospital, and one staff-model health maintenance organization. PATIENTS: Five hundred seventy-six adults (aged > or = 18 years) with clinical and radiographic evidence of pneumonia, judged by a validated pneumonia severity index to be at low risk of dying. MEASUREMENTS AND MAIN RESULTS: The presence and severity of five symptoms (cough, fatigue, dyspnea, sputum, and chest pain) were recorded through questionnaires administered at four time points: 0, 7, 30, and 90 days from the time of radiographic diagnosis of pneumonia. A summary symptom score was tabulated as the sum of the five individual severity scores. Patients also provided responses to the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) and reported the number of and reason for outpatient physician visits. Symptoms and health status 30 days before pneumonia onset (prepneumonia) were obtained at the initial interview. All symptoms, except pleuritic chest pain, were still commonly reported at 30 days, and the prevalence of each symptom at 90 days was still nearly twice prepneumonia levels. Physical health measures derived from the SF-36 Form declined significantly at presentation but continued to improve over all three follow-up time periods. Patients with elevated symptom scores at day 7 or day 30 were significantly more likely to report pneumonia-related ambulatory care visits at the subsequent day 30 or day 90 interviews, respectively. CONCLUSIONS: Disease-specific symptom resolution and recovery of the premorbid physical health status requires more than 30 days for many patients with pneumonia. Delayed resolution of symptoms is associated with increased utilization of outpatient physician visits.

Medical outcomes and antimicrobial costs with the use of the American Thoracic Society guidelines for outpatients with community-acquired pneumonia.

CONTEXT: The American Thoracic Society (ATS) published guidelines based on expert opinion and published data--but not clinically derived or validated--for treating adult outpatients with community-acquired pneumonia. OBJECTIVE: To compare medical outcomes and antimicrobial costs for patients whose antimicrobial therapy was consistent or inconsistent with ATS guidelines. DESIGN: Multicenter, prospective cohort study. SETTING: Emergency departments, medical clinics, and practitioner offices affiliated with 3 university hospitals, 1 community teaching hospital, and 1 health maintenance organization. PARTICIPANTS: A total of 864 immunocompetent, adult outpatients with community-acquired pneumonia: 546 aged 60 years or younger with no comorbidity and 318 older than 60 years or with 1 comorbidity or more. MAIN OUTCOME MEASURES: Patients' antimicrobial therapy was classified as being consistent or inconsistent with the ATS guidelines. Mortality, subsequent hospitalization, medical complications, symptom resolution, return to work and usual activities, health-related quality of life, and antimicrobial costs were compared among those treated consistently or inconsistently with the guidelines. RESULTS: Outpatients aged 60 years or younger with no comorbidity who were prescribed therapy consistent with ATS guidelines (ie, erythromycin with some exceptions) had 3-fold lower antimicrobial costs ($5.43 vs $18.51; P<.001) and no significant differences in medical outcomes. Outpatients older than 60 years or with 1 comorbidity or more who were prescribed therapy consistent with ATS guidelines (ie, second-generation cephalosporin, sulfamethoxazole-trimethoprim, or beta-lactam and beta-lactamase inhibitor with or without a macrolide) had 10-fold higher antimicrobial costs ($73.50 vs $7.50; P<.001); despite trends toward higher mortality and subsequent hospitalization, no significant differences in medical outcomes were observed. CONCLUSION: Our findings support the use of erythromycin as recommended by the ATS guidelines for outpatients aged 60 years or younger with no comorbidity. Although the antimicrobial therapy recommended in outpatients older than 60 years or with 1 comorbidity or more is more costly, this observational study provides no evidence of improved medical outcomes in the small subgroup who received ATS guideline-recommended therapy.

Early detection of prostate cancer. Part I: Prior probability and effectiveness of tests. The American College of Physicians.

PURPOSE: To estimate the prevalence of clinically important prostate cancer and to evaluate the effectiveness of digital rectal examination and measurement of prostate-specific antigen (PSA) in early detection of prostate cancer. DATA SOURCES: Relevant studies were identified from a structured MEDLINE search (1966 to 1995), reviews, bibliographies of retrieved articles, author files, and abstracts. STUDY SELECTION: Articles selected for analysis of test effectiveness were prospective cohort studies of early detection that did not have obvious selection bias. DATA EXTRACTION: Likelihood ratios for digital rectal examination and PSA measurement were estimated from studies that specified the age distribution of participants. DATA SYNTHESIS: In patients who have abnormalities on digital rectal examination, the risk for a large intracapsular tumor is increased twofold but the risk for extracapsular disease is increased threefold to ninefold. An elevation in PSA level greater than 4 ng/mL increases the odds of intracapsular tumors by as much as threefold and the odds of extracapsular tumors by threefold to fivefold. For studies in which biopsies were done if results of either test were abnormal, 18% to 26% of screened patients had suspicious results, cancer detection rates were approximately 4%, and the positive predictive value of the tests combined was 15% to 21%. Men who have lower urinary tract symptoms that are consistent with benign prostatic hyperplasia are not more likely to harbor prostate cancer; the specificity of PSA measurement is considerably lower among these men. CONCLUSIONS: Larger-volume tumors of the prostate are common among older men. Available tests for the early detection of cancer have limited specificity, which necessitates a relatively high biopsy rate. The positive predictive value of combined digital rectal examination and PSA measurement has been defined, but the negative predictive value is less clear. Measurement of PSA is the most sensitive noninvasive test for prostate cancer. However, digital rectal examination detects cancer that would otherwise be missed by PSA measurement.

Early detection of prostate cancer. Part II: Estimating the risks, benefits, and costs. American College of Physicians.

PURPOSE: To evaluate the potential benefits, harms, and economic consequences of digital rectal examination and measurement of prostate-specific antigen (PSA) for the early detection of prostate cancer. DATA SOURCES: Relevant studies were identified from a MEDLINE search (1966 to 1995), reviews, bibliographies of retrieved articles, author files, and abstracts. STUDY SELECTION: Probabilities for individual clinical outcomes were derived from various sources, including the largest screening study of community volunteers to data, analyses of Medicare claims, and recently published meta-analyses of the outcomes of alternative treatment strategies. Cost estimates were based on the 1992 Medicare fee schedule. DATA EXTRACTION: A cost-effectiveness model for one-time digital rectal examination and PSA measurement was constructed to examine the possible outcomes. RESULTS: If a favorable set of assumptions is used, one-time digital rectal examination and PSA measurement may increase average life expectancy by approximately 2 weeks at a reasonable marginal cost for men who are between 50 and 69 years of age. Considerable iatrogenic illness would occur. If less favorable assumptions are used, the estimated net benefit would decrease and cost-effectiveness ratios would dramatically increase. Even if favorable assumptions are used, the model suggests that screening adds only a few days to the average life expectancy of men who are older than 69 years of age. If the assumptions are less favorable, older men are harmed. CONCLUSIONS: The model suggests that screening may be reasonable in younger men if optimistic assumptions consistent with existing observational data are made. The lack of direct evidence showing a net benefit of screening for prostate cancer seems to mandate more clinician-patient discussion for this procedure than for many other routine tests.

A prediction rule to identify low-risk patients with community-acquired pneumonia.

BACKGROUND: There is considerable variability in rates of hospitalization of patients with community-acquired pneumonia, in part because of physicians' uncertainty in assessing the severity of illness at presentation. METHODS: From our analysis of data on 14,199 adult inpatients with community-acquired pneumonia, we derived a prediction rule that stratifies patients into five classes with respect to the risk of death within 30 days. The rule was validated with 1991 data on 38,039 inpatients and with data on 2287 inpatients and outpatients in the Pneumonia Patient Outcomes Research Team (PORT) cohort study. The prediction rule assigns points based on age and the presence of coexisting disease, abnormal physical findings (such as a respiratory rate of > or = 30 or a temperature of > or = 40 degrees C), and abnormal laboratory findings (such as a pH <7.35, a blood urea nitrogen concentration > or = 30 mg per deciliter [11 mmol per liter] or a sodium concentration <130 mmol per liter) at presentation. RESULTS: There were no significant differences in mortality in each of the five risk classes among the three cohorts. Mortality ranged from 0.1 to 0.4 percent for class I patients (P=0.22), from 0.6 to 0.7 percent for class II (P=0.67), and from 0.9 to 2.8 percent for class III (P=0.12). Among the 1575 patients in the three lowest risk classes in the Pneumonia PORT cohort, there were only seven deaths, of which only four were pneumonia-related. The risk class was significantly associated with the risk of subsequent hospitalization among those treated as outpatients and with the use of intensive care and the number of days in the hospital among inpatients. CONCLUSIONS: The prediction rule we describe accurately identifies the patients with community-acquired pneumonia who are at low risk for death and other adverse outcomes. This prediction rule may help physicians make more rational decisions about hospitalization for patients with pneumonia.

The hospital admission decision for patients with community-acquired pneumonia. Results from the pneumonia Patient Outcomes Research Team cohort study.

BACKGROUND: The hospital admission decision directly influences the magnitude of resource use in patients with community-acquired pneumonia, yet little information exists on how medical practitioners make this decision. OBJECTIVES: To determine which factors medical practitioners consider in making the hospital admission decision and which health care services they believe would allow ambulatory treatment of low-risk hospitalized patients with community-acquired pneumonia. METHODS: Medical practitioners responsible for the hospital admission decision for low-risk patients with community-acquired pneumonia were asked to describe patient characteristics at initial examination that influenced the hospitalization decision, and to identify the health care services that would have allowed initial outpatient treatment of hospitalized patients. RESULTS: A total of 292 medical practitioners completed questionnaires for 472 (76%) of the 624 low-risk patients eligible for this study. Although all patients had a predicted probability of death of less than 4%, practitioners estimated that 5% of outpatients and 41% of inpatients had an expected 30-day risk of death of more than 5%. Univariate analyses identified 3 practitioner-rated factors that were nearly universally associated with hospitalization: hypoxemia (odds ratio, 173.3; 95% confidence interval, 23.8-1265.0), inability to maintain oral intake (odds ratio, 53.3; 95% confidence interval, 12.8-222.5), and lack of patient home care support (odds ratio, 54.4; 95% confidence interval, 7.3-402.6). In patients without these 3 factors, logistic regression analysis demonstrated that practitioner-estimated risk of death of more than 5% had a strong independent association with hospitalization (odds ratio, 18.4; 95% confidence interval, 6.1-55.7). Practitioners identified home intravenous antibiotic therapy and home nursing observation as services that would have allowed outpatient treatment of more than half (68% and 59%, respectively) of the patients initially hospitalized for treatment. CONCLUSIONS: Practitioners' survey responses suggest that the availability of outpatient intravenous antimicrobial therapy and home nursing care would allow outpatient care for a large proportion of low-risk patients who are hospitalized for community-acquired pneumonia. These data also suggest that methods to improve practitioners' identification of low-risk patients with community-acquired pneumonia could decrease the hospitalization of such patients. Future studies are required to help physicians identify which low-risk patients could safely be treated in the outpatient setting on the basis of clinical information readily available at presentation.

The hospital discharge decision for patients with community-acquired pneumonia. Results from the Pneumonia Patient Outcomes Research Team cohort study.

BACKGROUND: The hospital discharge decision directly influences the length of stay in patients with community-acquired pneumonia, yet no information exists on how physicians make this decision. OBJECTIVES: To identify the factors physicians considered the factors responsible for extending length of hospital stay in clinically stable patients, and the outpatient medical services that would allow earlier hospital discharge for patients with community-acquired pneumonia. METHODS: Physicians responsible for the hospital discharge decision of patients with community-acquired pneumonia were asked to identify the factors responsible for extending stay in patients hospitalized beyond stability, and the medical services that could have allowed earlier hospital discharge to occur. RESULTS: For the 418 eligible patients with community-acquired pneumonia identified during the study, 332 questionnaires (79%) were completed by 168 physicians. Physicians believed 71 patients (22%) were discharged from the hospital 1 day or more (median, 2.5 days) after reaching clinical stability. The most common factors rated as being "very important" in delaying discharge were diagnostic evaluation or treatment of comorbid illness (56%), completion of a "standard course" of antimicrobials (15%), and delays with arrangements for long-term care (14%). Among the 302 patients with available information on both length of hospital stay and stability at discharge, median length of stay was 7.0 days for the 29 low-risk patients hospitalized beyond reaching clinical stability and 5.0 days for the remaining 128 low-risk patients (P < .005); median length of stay was 12.5 days for the 42 medium- and high-risk patients hospitalized beyond reaching clinical stability and 8.0 days in the remaining 113 medium- and high-risk patients (P < .001). Frequently cited medical services that "probably" or "definitely" would have allowed earlier discharge to occur included availability of home intravenous antimicrobial infusion (26%) and home visits by nurses (20%). CONCLUSIONS: Physicians believed that diagnostic evaluation or treatment of comorbid illness, completion of a standard course of antimicrobial therapy, and delays with arrangements for long-term care delayed hospital discharge in clinically stable patients. Addressing the efficiency of these aspects of inpatient medical care, as well as providing home treatment programs, could decrease the length of hospital stay in patients with community-acquired pneumonia.

Ambulatory patients with community-acquired pneumonia: the frequency of atypical agents and clinical course.

OBJECTIVES: To determine the etiology of community-acquired pneumonia in patients treated in an ambulatory setting, using serological methods, and to compare presenting symptoms, radiographic manifestations, and clinical outcomes of patients with pneumonia of "atypical" and undetermined etiology. PATIENTS AND METHODS: This prospective cohort study was conducted in emergency room and outpatient facilities of Victoria General Hospital, Halifax, Nova Scotia, and in offices of participating family doctors based in Halifax. One hundred forty-nine adults with acute onset of one or more symptoms or signs suggestive of pneumonia and radiographic evidence of pneumonia who provided informed consent were enrolled. Patients known to be HIV positive or who had been discharged from a hospital within the previous 10 days were ineligible for enrollment. Demographic features and clinical data were collected by direct patient interview and chart review by trained research nurses. Outcome measures included quantitative evaluation of pneumonia-specific symptoms, and responses to the Short Form 36 Health Survey at presentation and at 30 days after presentation. Information was also collected on each patient's health prior to pneumonia, as well as the time until each patient's self-reported return to work and to usual activities. The etiology of pneumonia was determined by testing acute and convalescent serum samples for antibodies to Legionella pneumophila serogroup 1, Mycoplasma pneumoniae, Chlamydia pneumoniae, Chlamydia psittaci, Coxiella burnetii, adenovirus, respiratory syncytia virus, influenza viruses A and B, and parainfluenza viruses 1, 2, 3. RESULTS: The study population consisted of 149 patients, 54 (36%) of whom were men, with a mean age (+/- SD) of 41 +/- 15 years. An etiological diagnosis was made in 74 (49.7%) patients using serological methods. Etiological agents included M pneumoniae 34 (22.8%); C pneumoniae 16 (10.7%); M pneumoniae and C pneumoniae 5 (3.4%); C burnetii 4 (2.7%); influenza A virus 4 (2.7%); and other agents 6% (7.4%). Three patients (2%) had a conventional bacterial etiology, and 72 patients (48.3%) had pneumonia of undetermined etiology. Patients with pneumonia of known (atypical) and undetermined etiology were similar in terms of age, gender, race, education, employment, and comorbidity. Despite a higher proportion of patients with pneumonia of known etiology reporting sweats, chills, and headache at presentation, the two groups were similar for symptom severity and bother. The patients with pneumonia of undetermined etiology were more likely to have multilobar pneumonia (P < 0.02). Both patients with atypical pneumonia and those with pneumonia of undetermined etiology suffered severe deterioration of physical functioning with a marked but incomplete recovery at 30 days. Those with atypical pneumonia had higher physical functioning and general mental health scores at 30 days. CONCLUSIONS: Nearly half the cases of ambulatory community-acquired pneumonia are due to "atypical" agents. It is not possible to reliably distinguish patients with atypical pneumonia from those with pneumonia of undetermined etiology by clinical features at baseline. The outcomes in terms of resolution of symptoms, functional status, return to work, and return to usual activities are essentially similar in the two groups.

Do pulmonary radiographic findings at presentation predict mortality in patients with community-acquired pneumonia?

BACKGROUND: Previous studies have reported conflicting results on whether pulmonary radiographic findings predict mortality for patients with community-acquired pneumonia (CAP). OBJECTIVE: To determine whether pulmonary radiographic findings at presentation are independently associated with 30-day mortality in patients with suspected CAP. METHODS: This study was conducted as part of the Pneumonia Patient Outcomes Research Team multicenter, prospective cohort study of ambulatory and hospitalized patients with clinical and radiographic evidence of CAP. For each patient with CAP, a structured data form was completed by a panel of radiologists to evaluate the radiographic pattern of infiltrate, number of lobes involved, presence of pleural effusion, and 8 other radiographic characteristics. Cox proportional hazards models were used to evaluate the independent association between radiographic findings and 30-day mortality, while controlling for patient demographic, clinical, and laboratory characteristics with a known association with this outcome. RESULTS: Of 2287 patients enrolled in the Pneumonia Patient Outcomes Research Team cohort study, 1906 patients (83.3%) had a pulmonary radiographic infiltrate confirmed by the radiology panel. Overall, 30-day mortality in this cohort was 4.9%. Univariate regression analyses demonstrated the following radiographic characteristics to be significantly associated with 30-day mortality: (1) bilateral pleural effusions (risk ratio [RR], 7.0; 95% confidence interval [CI], 3.9-12.6); (2) a pleural effusion of moderate or greater size (RR, 3.4; 95% CI, 1.4-8.4); (3) 2 or more lobes involved with infiltrate (RR, 2.5; 95% CI, 1.6-3.8); (4) bilateral infiltrate (RR, 2.8; 95% CI, 1.9-4.2); (5) bronchopneumonia (RR, 1.6; 95% CI, 1.0-2.7); and (6) air bronchograms (RR, 0.5; 95% CI, 0.2-0.9). Multivariate analysis of radiographic features and other clinical characteristics showed the presence of bilateral pleural effusions (RR, 2.8; 95% CI, 1.4-5.8) was independently associated with mortality. CONCLUSIONS: In patients with CAP, the presence of bilateral pleural effusions is an independent predictor of short-term mortality. This finding, which is available at presentation, can help guide physicians' assessment of prognosis in CAP.

Preferences for home vs hospital care among low-risk patients with community-acquired pneumonia.

OBJECTIVE: To measure preferences for initial outpatient vs hospital care among low-risk patients who were being actively treated for community-acquired pneumonia (CAP). METHODS: Study patients included 159 patients with CAP, 57 (36%) initially hospitalized, who were identified as being at low risk for early mortality using a validated prediction model. Subjects were enrolled from university and community health care facilities located in Boston, Mass, Halifax, Nova Scotia, and Pittsburgh, Pa, participating in the Pneumonia Patient Outcome Research Team prospective cohort study of CAP. Three utility assessment techniques (category scaling, standard gamble, and willingness to pay) were used to measure the strength of patient preferences for the site of care for low-risk CAP. At the time of initial therapy or during the early recuperative period, patient preferences were assessed across a spectrum of potential clinical outcomes using 7 standardized pneumonia clinical vignettes. RESULTS: Responses to the 7 pneumonia scenarios indicated that most patients consistently preferred outpatient-based therapy. This pattern was observed regardless of whether patients had actually been treated initially at home or in a hospital. Patients (74%) who stated that they generally preferred home care for low-risk CAP were willing to pay a mean of 24% of 1 month's household income to be assured of this preference. Preference for home care, as measured by the category scaling and the willingness to pay, persisted after adjustment for sociodemographic and baseline health status covariates. Sixty nine percent of interviewed patients said that their physician alone determined whether they would be treated in the hospital or at home. Only 11% recalled being asked if they had a preference for either site of care. CONCLUSIONS: Most patients, even those treated initially in a hospital, who were at low risk for mortality from CAP prefer outpatient treatment. However, most physicians appear not to involve patients in the site-of-care decision. More explicit discussion of patient preferences for the location of care would likely yield more highly valued care by patients as well as less costly treatment for CAP.