Age- and Sex-related Patterns of Care and Outcome in the United States |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
 |
ABSTRACT |
|---|
TOP
ABSTRACT
INTRODUCTION
METHODS
RESULTS
DISCUSSION
REFERENCES
|
|---|
Community-acquired pneumonia (CAP) is a frequent cause of hospital admission and death among elderly patients, but there is little information on age- and sex-specific incidence, patterns of care
(intensive care unit admission and mechanical ventilation), resource
use (length of stay and hospital costs), and outcome (mortality).
We conducted an observational cohort study of all Medicare recipients, aged 65 years or older, hospitalized in nonfederal U.S. hospitals in 1997, who met ICD-9-CM-based criteria for CAP. We identified 623,718 hospital admissions for CAP (18.3 per 1,000 population
65 years), of which 26,476 (4.3%) were from nursing homes and
of which 66,045 (10.6%) died. The incidence rose five-fold and mortality doubled as age increased from 65-69 to older than 90 years.
Men had a higher mortality, both unadjusted (odds ratio [OR]: 1.21 [95% CI: 1.19-1.23]) and adjusted for age, location before admission, underlying comorbidity, and microbiologic etiology (OR: 1.15 [95% CI: 1.13-1.17]). Mean hospital length of stay and costs per
hospital admission were 7.6 days and $6,949. For those admitted
to the intensive care unit (22.4%) and for those receiving mechanical ventilation (7.2%), mean length of stay and costs were 11.3 days and $14,294, and 15.7 days and $23,961, respectively. Overall
hospital costs were $4.4 billion (6.3% of the expenditure in the elderly for acute hospital care), of which $2.1 billion was incurred by
cases managed in intensive care units. We conclude that in the
hospitalized elderly, CAP is a common and frequently fatal disease
that often requires intensive care unit admission and mechanical
ventilation and consumes considerable health care resources. The
sex differences are of concern and require further investigation.
| |
INTRODUCTION |
|---|
|
TOP
ABSTRACT
INTRODUCTION
METHODS
RESULTS
DISCUSSION
REFERENCES
|
|---|
Keywords: pneumonia; intensive care; health resources; cost; age; sex
Over the last decade, community-acquired pneumonia (CAP) has been the focus of many quality improvement and cost containment efforts (1-6). Most of these efforts have centered on reducing unnecessary care for low-risk, uncomplicated cases, possibly contributing to the reported decline in average hospital length of stay (LOS) for CAP (1, 6). There has been arguably less focus on the standardization of care for sicker, high-risk patients, such as the elderly or those requiring mechanical ventilation. One explanation may be the logistic difficulty of standardizing the more complex care required for sicker patients. It is also possible that there is less concern for inappropriate care in this group or that such patients represent only a small proportion of the total number of CAP cases. However, recent data indicate that in the elderly both the incidence and mortality of CAP are rising (7).
Other data suggest sex may also be an important determinant of incidence and mortality. In animal studies, female sex hormones seem protective in sepsis (8, 9). Clinical data, however, are conflicting. Crabtree and coworkers found women who develop nosocomial pneumonia fare worse than men after adjusting for age and severity of illness (10). Others found either no sex effect on mortality (11) or better outcomes in women (12).
These data raise important questions regarding the current care of patients hospitalized with CAP. We conducted a study of all hospitalized cases of CAP in 1997 among the Medicare population aged 65 years or older. The objective of our study was to provide a contemporary assessment of the incidence, patterns of care, and outcome of hospitalized CAP in the elderly U.S. population and to determine differences by age and sex.
| |
METHODS |
|---|
|
TOP
ABSTRACT
INTRODUCTION
METHODS
RESULTS
DISCUSSION
REFERENCES
|
|---|
Data Sources
We linked four databases: a patient database (the 1997 Medicare Provider Analysis and Review hospital discharge database [MedPAR]; Centers for Medicare and Medicaid Services [CMS], Washington, DC); a population database (CB97-64, Population Estimates Program; U.S. Bureau of the Census, Washington DC); and two hospital databases (the 1997 Provider Specific File and Hospital Cost Report Minimum Dataset; CMS, Washington, DC). MedPAR contains all discharge records for Medicare beneficiaries using inpatient services at nonfederal acute-care hospitals or at skilled nursing facilities. MedPAR is created from Common Working File (CWF) claims records and validated through the National Claims History (NCH) Medicare Quality Assurance System (available at: www.cms.hhs.gov). For each discharge record, we selected age, sex, admission and discharge diagnosis and procedure codes (International Classification of Diseases, ninth revision, clinical modification [ICD-9-CM]) (13), source of admission, discharge status, hospital and intensive care unit (ICU) LOS, and hospital charges. To calculate costs, hospital charges were multiplied by the hospital-specific cost-to-charge ratio and expressed as 1997 U.S. dollars. We used 1997 U.S. census estimates to generate incidence rates (14).
Patient Selection
We selected all patients 65 years of age or older hospitalized in acute-care hospitals with a diagnosis of CAP. CAP was defined as either bacterial pneumonia (ICD-9-CM codes 481, 482, 485, or 486), listed both as the admission diagnosis and discharge diagnosis, or bacterial pneumonia, listed as a discharge diagnosis coupled with a pulmonary complaint at admission (respiratory failure [518.81], chronic obstructive pulmonary disease [COPD] [496], respiratory abnormality [786.09], complicated COPD [491.21], food/vomit pneumonitis [507.0], acute bronchitis [466.0], asthma without status asthmaticus [493.90], hemoptysis [786.3], or other pulmonary insufficiencies [518.82]). We excluded all patients transferred from other hospitals with the diagnosis of pneumonia (n = 7,300). We did not exclude nursing home residents, a population included in the most recent official statement of the American Thoracic Society on "Guidelines for the Management of Adults with Community-acquired Pneumonia" (15).
Patient Classification
We organized patients by age, sex, location before hospital admission, microbiological etiology, and underlying illness, defined as a Charlson-Deyo comorbidity index greater than zero (16) (see Table E1 in online data supplement). We defined a "complex course" of pneumonia as one involving ICU admission or mechanical ventilation. We determined the incidence of nonpulmonary organ dysfunction using a previously developed ICD-9-CM-based scheme (17) and classified pulmonary complications using specific ICD-9-CM codes.
Data Analyses
We analyzed incidence, case number, comorbidity, distribution of complex cases, LOS, costs, overall mortality, and mortality within age and sex. We categorized baseline characteristics as needed. We present means and medians for continuous data and counts and rates for categorical data. Univariate analyses were conducted by Wilcoxon-Mann-Whitney test and by Chi-square test. We developed a generalized logit link (mathematical transformation) regression (18) for hospital mortality using all baseline characteristics as covariates. The model was constructed on one half of the data and validated on the other half. Performance was assessed by the likelihood ratio statistic (R2L) and the Hosmer-Lemeshow C statistic (19). Crude and adjusted odds ratios for mortality were recalculated for the entire cohort. We managed data using Visual FoxPro (Microsoft Corp, Redmond, WA) and conducted analyses using Data Desk (Data Description Inc, Ithaca, NY).
| |
RESULTS |
|---|
|
TOP
ABSTRACT
INTRODUCTION
METHODS
RESULTS
DISCUSSION
REFERENCES
|
|---|
Nationwide, we identified 623,718 cases of hospitalized CAP in the elderly population. Pneumonia was diagnosed both at admission and discharge in 79.3% of the study cohort. The remaining 20.7% had a diagnosis of pneumonia at discharge coupled with a pulmonary complaint on admission. Characteristics of the entire study cohort are provided in Table 1. The mean age of the study population was 77 years. More than two thirds had an underlying disease, with congestive heart failure, chronic pulmonary disease, and diabetes mellitus reported most commonly. In more than two thirds of all cases, no specific microbiologic etiology was identified. Women comprised slightly more than half of the study cohort, were older (77.7 versus 76.2 years, p < 0.001), and were less likely to suffer from underlying illness (Charlson-Deyo comorbidity index 1.01 versus 1.18, p < 0.001). Men were more likely to suffer from gram-negative infections (14.3% versus 11.5%, p < 0.001) and less likely to have an unspecified etiology (71.5% versus 76.3%, p < 0.001).
|
Nursing home residents, who comprised almost 5% of the study cohort, were older (mean age 80 versus 76.8 years, p < 0.001), more likely to be women (58.1% versus 53.4%, p < 0.001), more likely to suffer from underlying illness (Charlson-Deyo comorbidity index 1.09 versus 1.22, p < 0.001), and less likely to have an etiology specified (67.5% versus 70.6%, p < 0.001). The frequency of gram-negative enteric infections among nursing home residents was slightly higher than for the remainder of the cohort (10.1% versus 9.6%, p < 0.001).
Generally, those listed with pneumonia at discharge only were similar to those diagnosed with pneumonia at both discharge and admission (mean age 75.5 versus 77.3 years, p < 0.001; male 48.1% versus 46.1%, p < 0.001; Charlson-Deyo comorbidity index 1.13 versus 1.08, p < 0.001; no etiology specified 66.2% versus 71.5%, p < 0.001; enteric gram-negative etiology 9.9% versus 9.5%, p < 0.001), although differences remained significant because of large sample size.
Incidence
The incidence of hospitalized CAP in those 65 years of age or older was 18.3 cases per 1,000 population. The age-specific number of cases and incidence are shown in Figure 1. The incidence rose more than five-fold with age from 8.4 per 1,000 in those aged 65-69 years to 48.5 per 1,000 in those aged 90 years and older. The number of cases, however, fell beyond age 80 because of the age distribution of the underlying population. Although there were more women in the study cohort, the incidence rate was higher in men (19.4 versus 15.6 cases per 1,000 population, p < 0.001). This higher incidence persisted across all age groups such that men had an incidence similar to that of women five years older (Figure 2).
|
Number of
cases.
|
Hospital Course
We identified 140,226 complex cases, of whom 95,589 (68.2%) received ICU care alone, 41,355 (29.5%) received ICU care and mechanical ventilation, and 3,282 (2.3%) received mechanical ventilation outside the ICU, presumably in intermediate care facilities. Overall, complex cases represented 22.5% of the entire cohort. Younger cases were more likely to be complex, with the proportion dropping from 26.7% in those aged 65-69 years to 14.7% in those aged 90 years and older (Figure 3). Men were also more likely to be managed with a complex course, both overall (24.4% versus 20.8%, p < 0.001) and across all age groups (Figure 2). Not surprisingly, patients who incurred a complex course were more likely to have underlying disease (Charlson-Deyo comorbidity index 1.26 versus 1.05, p < 0.001) and to develop pulmonary complications (12.8% versus 8.3%, p < 0.001) or nonpulmonary organ dysfunction (7.6% versus 4.7%, p < 0.001) (Table 2).
|
occurrence rate; 
hospital mortality.
|
Mortality
The hospital mortality for the entire cohort was 10.6% (n = 66,045). Hospital mortality doubled with age from 7.8% in those aged 65-69 years to 15.4% in those aged 90 years and older (Figure 1). Mortality was higher in nursing home residents (17.6 versus 10.3%, p < 0.001). Mortality was also higher in patients with an underlying illness (11.9% versus 7.6%, p < 0.001) and varied with microbiologic etiology. Mortality was higher in men than in women, both overall (11.6% versus 9.8%, p < 0.001) and within age groups (Figure 2). Crude odds ratios for mortality for different baseline characteristics are provided in Table 1. The mortality model performed well with the link parameter set at 15 (R2L = 64.8, Hosmer-Lemeshow C statistic = 31.0 [8 df], and area under the receiver operating characteristic [ROC] curve = 0.654 [maximal ROC for data = 0.6786] for the development set, and R2L = 64.98 and Hosmer-Lemeshow C statistic = 66.0 [8 df] for the validation set). In the validation cohort, there were 33,114 actual deaths and 33,076 predicted deaths (standardized mortality ratio = 0.999 [95% CI 0.985-1.014]). Odds ratios for mortality adjusted for baseline characteristics are provided in Table 1. As expected, increasing age, residence in a nursing home, and comorbidity remained significant predictors of death after adjustment. Adjusted odds for death were also increased for men, although this effect was small (OR: 1.15, 95% CI 1.13-1.17).
Crude odds ratios for mortality of pulmonary and nonpulmonary complication for simple and complex course of pneumonia are provided in Table 2. Not surprisingly, patients with a complex course of pneumonia had a much higher mortality (22.5% versus 7.1% for complex versus simple course, p < 0.001), as did patients developing acute organ dysfunction (23.2% versus 9.9% for any organ dysfunction versus no organ dysfunction, p < 0.001). Of note, mortality for patients 90 years of age and older was 15.4% overall, 30.2% for complex cases, and 55.4% for those receiving mechanical ventilation.
Most deaths occurred early, with one out of four (n = 18,023) occurring within 48 hours of hospital admission (Figure 4). Patients dying early during the hospital course were older (79.6 versus 78.3, p < 0.001) and more likely to be nursing home residents (8.2% versus 6.7%, p < 0.001).
|
Resource Use and Costs of Care
Mean LOS and cost per hospital admission were 7.6 days and $6,949. Patients with a complex course, especially those receiving mechanical ventilation, had much higher LOS and costs (Table 3). There was a small decrease in LOS and a large decrease in costs with age (7.7 days and $7,768 for those aged 65-69 years versus 7.4 days and $5,683 for those aged 90 years and older, p < 0.001 for both comparisons), mainly due to a higher proportion of complex cases in younger patients (26.7% for those aged 65-69 years versus 14.7% for those over 90 years of age, p < 0.001). Mean LOS was similar for men and women (7.6 versus 7.7 days) but mean costs were higher for men ($7,206 versus $6,726, p < 0.001), mainly due to the higher likelihood for men to be managed with a complex course (24.4% versus 20.8%, p < 0.001). Overall, nonsurvivors had higher LOS and costs compared with survivors (9.1 and $11,795 versus 7.5 and $6,375, respectively, p < 0.001 for both comparisons), primarily because nonsurvivors were more likely to incur complex courses.
|
Burden of Hospitalized CAP on the Medicare Hospital Budget
In 1997, Medicare covered 34 million Americans. During that year, there were 10 million acute care hospital admissions, accounting for 69 million hospital days, 8.5 million ICU days, $70 billion hospital costs, and 536,173 hospital deaths. Patients hospitalized with CAP accounted for 6.2% of admissions (623,718), 6.3% of costs ($4.4 billion), 7% of hospital days (4.8 million), 7.4% of ICU days (633,232), and 12.3% of hospital deaths (66,044). The percentage of hospital admissions attributable to CAP increased with age from 4.5% in those aged 65- 69 years to 9.7% for those aged 90 years and older. One out of five cases had a complex course, and half of the hospital costs attributable to hospitalized CAP ($2.1 billion) were incurred by patients with a complex course. Expenses for nonsurvivors totaled $779 million, of which 73.8% were spent in nonsurvivors of ICU care.
| |
DISCUSSION |
|---|
|
TOP
ABSTRACT
INTRODUCTION
METHODS
RESULTS
DISCUSSION
REFERENCES
|
|---|
Our study reinforces prior findings (20, 21) that CAP is a major clinical problem in the U.S. and further suggests that the burden of this disease will grow substantially in the coming years. Many patients hospitalized with CAP were very sick, as evidenced by the common use of intensive care, life support, and the high mortality rates. Even in the oldest patients, there was a strong commitment to provide aggressive care. We also present new information on important variations in process of care and outcome by age and sex. Men were more likely to be hospitalized with CAP, more likely to receive intensive care or life support, and more likely to die.
Assuming the U.S. census projected population estimates and a constant age-specific incidence of hospitalized CAP, we forecast the annual number of cases to rise to 750,000 in the year 2010, and 1 million in the year 2020, due to the disproportionate growth of the elderly population.
To initiate mechanical ventilation for a 90-year old patient with pneumonia may seem aggressive or even excessive. Yet we found such care was provided commonly and that almost half of the patients older than 90 years who received mechanical ventilation were discharged alive, supporting the belief that such care for the critically ill elderly patient is often justified (22, 23). It is probable, however, that many factors other than the patient's severity of respiratory failure influence the decision to initiate mechanical ventilation. A decrease in hospital costs with age, which was due to a lower proportion of complex cases in the oldest patients, was not explained by less severe disease. Presumably, therefore, it reflected greater use of advanced directives or limitations on care. Certainly, the decision to provide intensive care varied widely in prior studies of patients with CAP (24, 25), raising the possibility that the decision to provide intensive care or life support may be strongly influenced by local practice patterns. Just as prior efforts have sought to standardize and improve the hospital admission decision (2, 4, 26, 27), we recommend efforts to standardize and improve decisions to provide intensive care and life support. A better understanding of the long-term survival and quality of life after complex hospital care for these patients will also be essential.
The differences we observed between men and women are consistent with animal (8, 9) and human (12) studies suggesting that females are less likely to develop sepsis or to die from it but conflict with those observed in nosocomial pneumonia (10). The reasons for these discrepancies are not clear. Prior clinical studies were from single centers without population-based incidence rates, potentially leading to selection bias. Sex differences may not simply be due to biologic differences but also to many other factors, such as access to care (28). For example, a sex bias in the hospital admission decision could both explain the reduced incidence of hospitalized CAP in women and confound interpretation of hospital mortality rates. Further research on sex differences should focus on differences in both the biological response to infection and patterns of health care delivery.
The large number of deaths on day one of hospital admission is of concern. Presumably, the decision to hospitalize implies that a patient can receive elements of care that improve outcome yet cannot be provided easily elsewhere (e.g., intravenous antibiotics, life support, or certain diagnostic tests). Many of these elements of care are not expected to reverse a patient's course in one day. Some of the early hospital deaths, therefore, might have been averted had patients been hospitalized sooner. In other instances, death may have been considered inevitable and preceded by withdrawal of support. If so, it may have been more appropriate to avoid hospital admission in the first place. In other words, the high number of early deaths suggests many patients received hospital care that was either too late or inappropriate. Currently, the focus on improving the hospital admission decision has been limited to decreasing hospital care for low risk cases (2, 4). We recommend expanding that focus to explore earlier hospitalization for high-risk patients and better options for patients requiring end-of-life care.
Our study has limitations. We relied on administrative data,
which are restricted in quality and detail (29). This may have resulted in incorrect identification of patients with CAP. However, using selection criteria based on both the admission diagnosis and all discharge diagnoses minimized inclusion of nosocomial pneumonia (a confounder in prior ICD-9-CM-based CAP studies) and avoided exclusion of patients with a complicated course,
where the principal discharge diagnosis was not pneumonia
(e.g., respiratory failure or tracheotomy). Patients who had a
pulmonary complaint as reason for hospital admission and who
developed pneumonia in the hospital (e.g., COPD) might have
been misclassified as CAP. However, such misclassification was
unlikely, especially in surgical patients
the group at highest risk
for nosocomial pneumoniabecause surgery is often postponed
when surgical patients have pulmonary complaints. The data
curtailed our ability to assess the extent to which differences in
severity of illness explained differences in mortality rates. The
data also restricted our exploration of processes of care, such as
the use and timing of different procedures (e.g., bronchoscopy).
The high incidence of pneumonia that was either unspecified or
attributed to gram-negative organisms might have been due in
part to coding biases. If our study cohort had included patients
from Veteran Administration hospitals, which account for 5%
of all U.S. hospital admissions and the majority of whom are
males, our finding of a higher incidence of pneumonia in men
would have been further magnified. Although hospital-specific cost-to-charge ratios have been shown to compare well to detailed cost accounting methods for estimating true costs (30), we
did not capture the cost of physician services, outpatient services, and home health care services, which account for roughly
one quarter of the total cost for a hospitalized pneumonia episode (31). By extrapolation, a more comprehensive estimate of
the national costs for hospitalized CAP in the elderly population
would be $6.4 billion. Despite these limitations, administrative
data provide a valuable opportunity to understand population-based information on incidence, patient characteristics, delivery
of care, outcome, and resource use.
In conclusion, hospitalized CAP in the elderly is a common, expensive, and frequently fatal disease. There were considerable differences between men and women, which require further investigation. A quarter of all patients required intensive care or life support. Therefore, optimal care must include a focus on early, appropriate decision-making, not only regarding hospital admission, but also regarding the use of intensive care services. The anticipated growth of the elderly U.S. population will dramatically increase the national burden of this disease in the near future.
| |
Footnotes |
|---|
Correspondence and requests for reprints should be addressed to Derek C. Angus, M.D., M.P.H., Room 604 Scaife Hall, Critical Care Medicine, University of Pittsburgh, 200 Lothrop Street, Pittsburgh, PA 15213; E-mail: angusdc{at}ccm.upmc.edu
(Received in original form March 8, 2001 and accepted in revised form January 2, 2002).
This article has an online data supplement, which is accessible from this issue's table of contents online at www.atsjournals.org
Acknowledgments:
Supported in part by an unrestricted educational grant from AMGEN, Inc. by R01
GM61992-01, National Institute of General Medical Sciences (D. C. Angus) and by
the Stiefel-Zangger Foundation, University of Zürich, Zürich, Switzerland (V. Kaplan).
| |
References |
|---|
|
TOP
ABSTRACT
INTRODUCTION
METHODS
RESULTS
DISCUSSION
REFERENCES
|
|---|
1. McCormick D, Fine MJ, Coley CM, Marrie TJ, Lave JR, Obrosky DS, Kapoor WN, Singer DE. Variation in length of hospital stay in patients with community-acquired pneumonia: are shorter stays associated with worse medical outcomes? Am J Med 1999; 107: 5-12 [Medline].
2.
Fine MJ,
Auble TE,
Yealy DM,
Hanusa BH,
Weissfeld LA,
Singer DE,
Coley CM,
Marrie TJ,
Kapoor WN.
A prediction rule to identify low-risk patients with community-acquired pneumonia.
N Engl J Med
1997;
336:
243-250
3.
Gleason PP,
Kapoor WN,
Stone RA,
Lave JR,
Obrosky DS,
Schulz R.
Singer DE, Coley CM, Marrie TJ, Fine MJ. Medical outcomes and antimicrobial costs with the use of the American Thoracic Society guidelines for outpatients with community-acquired pneumonia.
JAMA
1997;
278:
32-39
4.
Marrie TJ,
Lau CY,
Wheeler SL,
Wong CJ,
Vandervoort MK,
Feagan BG.
A controlled trial of a critical pathway for the treatment of community acquired pneumonia. CAPITAL Study Investigators. Community-Acquired Pneumonia Intervention Trial Assessing Levofloxacin.
JAMA
2000;
283:
749-755
5. Gilbert K, Gleason PP, Singer DE, Marrie TJ, Coley CM, Obrosky DS, Lave JR, Kapoor WN, Fine MJ. Variations in antimicrobial use and cost in more than 2,000 patients with community-acquired pneumonia. Am J Med 1998; 104: 17-27 [Medline].
6. Weingarten SR, Riedinger MS, Hobson P, Noah MS, Johnson B, Giugliano G, Norian J, Belman MJ, Ellrodt AG. Evaluation of a pneumonia practice guideline in an interventional trial. Am J Respir Crit Care Med 1996; 153: 1110-1115 [Abstract].
7. National Center for Health Statistics. Health, United States, 1999 (with Health and Aging Chartbook). Hyattsville, MD: National Center for Health Statistics; 2000.
8. Zellweger R, Wichmann MW, Ayala A, Stein S, DeMaso CM, Chaudry IH. Females in proestrus state maintain splenic immune functions and tolerate sepsis better than males. Crit Care Med 1997; 25: 106-110 [Medline].
9. Angele MK, Schwacha MG, Ayala A, Chaudry IH. Effect of gender and sex hormones on immune responses following shock. Shock 2000; 14: 81-90 [Medline].
10.
Crabtree TD,
Pelletier SJ,
Gleason TG,
Pruett TL,
Sawyer RG.
Gender-dependent differences in outcome after the treatment of infection in
hospitalized patients.
JAMA
1999;
282:
2143-2148
11. Wichmann MW, Inthorn D, Andress H-J, Schildberg FW. Incidence and mortality of severe sepsis in surgical intensive care patients: the influence of patient gender on disease process and outcome. Intensive Care Med 2000; 26: 167-172 [Medline].
12.
Schroder J,
Kahlke V,
Staubach KH,
Zabel P,
Stuber F.
Gender differences in human sepsis.
Arch Surg
1998;
133:
1200-1205
13. Fetter RB, Thompson JD, Averill RA. The New ICD-9-CM Diagnosis Related Group Classification Scheme: Users Manual. New Haven, CT: Health Systems Management Group, School of Management, Yale University; 1981.
14. US Bureau of Census. Population Estimates Program. Washington, DC: US Bureau of Census; 1990. Report No. CB97-64.
15. American Thoracic Society. Guidelines for the management of adults with community-acquired pneumonia. Am J Respir Crit Care Med 2001;163:1730-1754.
16. Deyo RA, Cherkin DC, Ciol MA. Adapting a clinical co-morbidity index for use with ICD-9 CM administrative databases. J Clin Epidemiol 1992; 45: 613-619 [Medline].
17. Angus DC, Linde-Zwirble WT, Lidicker J, Clermont G, Carcillo J, Pinsky MR. Epidemiology of severe sepsis in the United States: analysis of incidence, outcome, and associated costs of care. Crit Care Med 2001; 29: 1303-1310 [Medline].
18. Generalized logit link. In: Proceedings of the International Conference on Health Policy Research; December 3, 1995; Boston, MA.
19. McCullagh P, Nelder JA. Generalized Linear Models. London: Chapman & Hall; 1989.
20. Lave JR, Lin CJ, Fine MJ, Hughes-Cromwick P. The cost of treating patients with community-acquired pneumonia. Semin Respir Med 1999; 20: 189-197 .
21. Niederman MS, McCombs JS, Unger AN, Kumar A, Popovian R. The cost of treating community-acquired pneumonia. Clin Ther 1998; 20: 820-837 [Medline].
22.
Chelluri L,
Grenvik AN,
Silverman M.
Intensive care for critically ill elderly: mortality, costs, and quality of life. Review of the literature.
Arch Intern Med
1995;
155:
1013-1022
23. Chelluri L, Pinsky MR, Grenvik AN. Outcome of intensive care of the "oldest-old" critically ill patients. Crit Care Med 1992; 20: 757-761 [Medline].
24. Ortqvist AB, Sterner G, Nilsson JA. Severe community-acquired pneumonia: factors influencing need of intensive care treatment and prognosis. Scand J Infect Dis 1985; 17: 377-386 [Medline].
25. Feagan BG, Marrie TJ, Lau CY, Wheeler SL, Wong CJ, Vandervoort MK. Treatment and outcomes of community-acquired pneumonia at Canadian hospitals. CMAJ 2000; 162: 1415-1420 . [Medline]
26. Fine MJ. Pneumonia in the elderly: the hospital admission and discharge decisions. Semin Respir Infect 1990; 5: 303-313 [Medline].
27. Fine MJ, Smith DN, Singer DE. Hospitalization decision in patients with community-acquired pneumonia: a prospective cohort study. Am J Med 1990; 89: 713-721 [Medline].
28.
Giles WH,
Anda RF,
Casper ML,
Escobedo LG,
Taylor HA.
Race and
sex differences in rates of invasive cardiac procedures in US hospitals.
Data from the National Hospital Discharge Survey.
Arch Intern Med
1995;
155:
318-324
29. Iezzoni LI. Using administrative diagnostic data to assess the quality of hospital care. Pitfalls and potential of ICD-9-CM. Int J Technol Assess Health Care 1990; 6: 272-281 [Medline].
30. Shwartz M, Young DW, Siegrist R. The ratio of costs to charges: how good a basis for estimating costs? Inquiry 1995; 32: 476-481 .
31. Whittle J, Lin CJ, Lave JR, Joyce DZ, Young WW, Hough LJ, Kapoor WN. Relationship of provider characteristics to outcomes, process, and costs of care for community-acquired pneumonia. Med Care 1998; 36: 977-987 [Medline].
This article has been cited by other articles:
 |
|
 |
|
  M. Cabre, M. Serra-Prat, E. Palomera, J. Almirall, R. Pallares, and P. Clave Prevalence and prognostic implications of dysphagia in elderly patients with pneumonia Age Ageing, January 1, 2010; 39(1): 39 - 45. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Torres and R. Menendez Meeting the old man's friend Thorax, December 1, 2009; 64(12): 1016 - 1017. [Full Text] [PDF]
|
|
|
|
|
|
S Ewig, N Birkner, R Strauss, E Schaefer, J Pauletzki, H Bischoff, P Schraeder, T Welte, and G Hoeffken New perspectives on community-acquired pneumonia in 388 406 patients. Results from a nationwide mandatory performance measurement programme in healthcare quality Thorax, December 1, 2009; 64(12): 1062 - 1069. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. McCabe, C. Kirchner, H. Zhang, J. Daley, and D. N. Fisman Guideline-Concordant Therapy and Reduced Mortality and Length of Stay in Adults With Community-Acquired Pneumonia: Playing by the Rules Arch Intern Med, September 14, 2009; 169(16): 1525 - 1531. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 I. Watanabe, S. Kuriyama, M. Kakizaki, T. Sone, K. Ohmori-Matsuda, N. Nakaya, A. Hozawa, and I. Tsuji Green tea and death from pneumonia in Japan: the Ohsaki cohort study Am. J. Clinical Nutrition, September 1, 2009; 90(3): 672 - 679. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R Menendez, R Martinez, S Reyes, J Mensa, X Filella, M A Marcos, A Martinez, C Esquinas, P Ramirez, and A Torres Biomarkers improve mortality prediction by prognostic scales in community-acquired pneumonia Thorax, July 1, 2009; 64(7): 587 - 591. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Singanayagam, J.D. Chalmers, and A.T. Hill Severity assessment in community-acquired pneumonia: a review QJM, June 1, 2009; 102(6): 379 - 388. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A Capelastegui, P P Espana, J M Quintana, A Bilbao, R Menendez, R Zalacain, and A Torres Development of a prognostic index for 90-day mortality in patients discharged after admission to hospital for community-acquired pneumonia Thorax, June 1, 2009; 64(6): 496 - 501. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Kothe, T. Bauer, R. Marre, N. Suttorp, T. Welte, K. Dalhoff, and the Competence Network for Community-Acquired Pneu Outcome of community-acquired pneumonia: influence of age, residence status and antimicrobial treatment Eur. Respir. J., July 1, 2008; 32(1): 139 - 146. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Reyes, R. Martinez, J. M. Valles, E. Cases, and R. Menendez Determinants of hospital costs in community-acquired pneumonia Eur. Respir. J., May 1, 2008; 31(5): 1061 - 1067. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R Menendez, M Cavalcanti, S Reyes, J Mensa, R Martinez, M A Marcos, X Filella, M Niederman, and A Torres Markers of treatment failure in hospitalised community acquired pneumonia Thorax, May 1, 2008; 63(5): 447 - 452. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Guo, J. Liu, A. J. Collins, and R. N. Foley Pneumonia in incident dialysis patients--the United States Renal Data System Nephrol. Dial. Transplant., February 1, 2008; 23(2): 680 - 686. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. B. Kornum, R. W. Thomsen, A. Riis, H.-H. Lervang, H. C. Schonheyder, and H. T. Sorensen Type 2 Diabetes and Pneumonia Outcomes: A population-based cohort study Diabetes Care, September 1, 2007; 30(9): 2251 - 2257. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Valencia, J. R. Badia, M. Cavalcanti, M. Ferrer, C. Agusti, J. Angrill, E. Garcia, J. Mensa, M. S. Niederman, and A. Torres Pneumonia Severity Index Class V Patients With Community-Acquired Pneumonia: Characteristics, Outcomes, and Value of Severity Scores Chest, August 1, 2007; 132(2): 515 - 522. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Pepersack and S. de Breucker Could geriatric comprehensive assessment predict the outcome of pneumonia in the very old? Age Ageing, July 1, 2007; 36(4): 455 - 459. [Full Text] [PDF]
|
|
|
|
|
|
R. Menendez, S. Reyes, R. Martinez, P. de la Cuadra, J. Manuel Valles, and J. Vallterra Economic evaluation of adherence to treatment guidelines in nonintensive care pneumonia Eur. Respir. J., April 1, 2007; 29(4): 751 - 756. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. P. Espana, A. Capelastegui, I. Gorordo, C. Esteban, M. Oribe, M. Ortega, A. Bilbao, and J. M. Quintana Development and Validation of a Clinical Prediction Rule for Severe Community-acquired Pneumonia Am. J. Respir. Crit. Care Med., December 1, 2006; 174(11): 1249 - 1256. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. F. Shorr, M. Bodi, A. Rodriguez, J. Sole-Violan, J. Garnacho-Montero, J. Rello, and for the CAPUCI Study Investigators Impact of antibiotic guideline compliance on duration of mechanical ventilation in critically ill patients with community-acquired pneumonia. Chest, July 1, 2006; 130(1): 93 - 100. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Christ-Crain, D. Stolz, R. Bingisser, C. Muller, D. Miedinger, P. R. Huber, W. Zimmerli, S. Harbarth, M. Tamm, and B. Muller Procalcitonin Guidance of Antibiotic Therapy in Community-acquired Pneumonia: A Randomized Trial Am. J. Respir. Crit. Care Med., July 1, 2006; 174(1): 84 - 93. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Dremsizov, G. Clermont, J. A. Kellum, K. G. Kalassian, M. J. Fine, and D. C. Angus Severe sepsis in community-acquired pneumonia: when does it happen, and do systemic inflammatory response syndrome criteria help predict course? Chest, April 1, 2006; 129(4): 968 - 978. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. S. Niederman, C. Feldman, and G. A. Richards Combining information from prognostic scoring tools for CAP: an American view on how to get the best of all worlds. Eur. Respir. J., January 1, 2006; 27(1): 9 - 11. [Full Text] [PDF]
|
|
|
|
|
|
A. Capelastegui, P. P. Espana, J. M. Quintana, I. Areitio, I. Gorordo, M. Egurrola, and A. Bilbao Validation of a predictive rule for the management of community-acquired pneumonia Eur. Respir. J., January 1, 2006; 27(1): 151 - 157. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. M. Fry, D. K. Shay, R. C. Holman, A. T. Curns, and L. J. Anderson Trends in Hospitalizations for Pneumonia Among Persons Aged 65 Years or Older in the United States, 1988-2002 JAMA, December 7, 2005; 294(21): 2712 - 2719. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. M. File Jr and J. S. Tan Pneumonia in Older Adults: Reversing the Trend JAMA, December 7, 2005; 294(21): 2760 - 2763. [Full Text] [PDF]
|
|
|
|
 |
|
 D. Aronsky, P. J. Haug, C. Lagor, and N. C. Dean Accuracy of Administrative Data for Identifying Patients With Pneumonia American Journal of Medical Quality, November 1, 2005; 20(6): 319 - 328. [Abstract] [PDF]
|
|
|
|
|
|
E. B. Milbrandt and D. C. Angus What's in a Day? Chest, November 1, 2005; 128(5): 3091 - 3093. [Full Text] [PDF]
|
|
|
|
 |
|
 E. P. Rivers, L. McIntyre, D. C. Morro, and K. K. Rivers Early and innovative interventions for severe sepsis and septic shock: taking advantage of a window of opportunity Can. Med. Assoc. J., October 25, 2005; 173(9): 1054 - 1065. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Menendez, A. Torres, R. Zalacain, J. Aspa, J. J. Martin-Villasclaras, L. Borderias, J. M. Benitez-Moya, J. Ruiz-Manzano, F. R. de Castro, J. Blanquer, et al. Guidelines for the Treatment of Community-acquired Pneumonia: Predictors of Adherence and Outcome Am. J. Respir. Crit. Care Med., September 15, 2005; 172(6): 757 - 762. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. Martin-Harris, M. B. Brodsky, Y. Michel, C. L. Ford, B. Walters, and J. Heffner Breathing and Swallowing Dynamics Across the Adult Lifespan Arch Otolaryngol Head Neck Surg, September 1, 2005; 131(9): 762 - 770. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. N. Hansel, B. Merriman, E. F. Haponik, and G. B. Diette Hospitalizations for Tuberculosis in the United States in 2000: Predictors of In-Hospital Mortality Chest, October 1, 2004; 126(4): 1079 - 1086. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. L. Colice, M. A. Morley, C. Asche, and H. G. Birnbaum Treatment Costs of Community-Acquired Pneumonia in an Employed Population Chest, June 1, 2004; 125(6): 2140 - 2145. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Ohkubo, N. Chapman, B. Neal, M. Woodward, T. Omae, and J. Chalmers Effects of an Angiotensin-converting Enzyme Inhibitor-based Regimen on Pneumonia Risk Am. J. Respir. Crit. Care Med., May 1, 2004; 169(9): 1041 - 1045. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Yamazaki, S. Ogura, A. Ishizaka, T. Oh-hara, and M. Nishimura Bronchoscopic Microsampling Method for Measuring Drug Concentration in Epithelial Lining Fluid Am. J. Respir. Crit. Care Med., December 1, 2003; 168(11): 1304 - 1307. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. E. Marik and D. Kaplan Aspiration Pneumonia and Dysphagia in the Elderly Chest, July 1, 2003; 124(1): 328 - 336. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. A. Jackson, K. M. Neuzil, O. Yu, P. Benson, W. E. Barlow, A. L. Adams, C. A. Hanson, L. D. Mahoney, D. K. Shay, W. W. Thompson, et al. Effectiveness of Pneumococcal Polysaccharide Vaccine in Older Adults N. Engl. J. Med., May 1, 2003; 348(18): 1747 - 1755. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Metersky, D. C. Angus, and W. T. Linde-Zwirble Estimated frequency of nursing facility-acquired pneumonia? Am. J. Respir. Crit. Care Med., May 1, 2003; 167(9): 1287 - 1288. [Full Text] [PDF]
|
|
|
|
|
|
R. Zalacain, A. Torres, R. Celis, J. Blanquer, J. Aspa, L. Esteban, R. Menendez, R. Blanquer, and L. Borderias Community-acquired pneumonia in the elderly: Spanish multicentre study Eur. Respir. J., February 1, 2003; 21(2): 294 - 302. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. J. Tobin Critical Care Medicine in AJRCCM 2002 Am. J. Respir. Crit. Care Med., February 1, 2003; 167(3): 294 - 305. [Full Text] [PDF]
|
|
|
|
|
|
M. J. Tobin Tuberculosis, Lung Infections, Interstitial Lung Disease, and Journalology in AJRCCM 2002 Am. J. Respir. Crit. Care Med., February 1, 2003; 167(3): 345 - 355. [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Proc. Am. Thorac. Soc. | Am. J. Respir. Cell Mol. Biol. |