Community-acquired pneumonia (CAP) is a common medical illness with a prognosis that ranges from rapid complete recovery to severe medical complications and death. Approximately 4 million adults are diagnosed with CAP in the United States each year, with more than 600, 000 (15%) hospitalized. <sup>16 Garibaldi R.A. Epidemiology of community-acquired respiratory tract infections in adults: Incidence, etiology, and impact Am J Med 1985 ;  78 : 32-37  [cross-ref]

Cliccare qui per andare alla sezione Riferimenti, 27 Medicare and Medicaid statistical supplement Health Care Finance Rev 1995 ;  16 :

Cliccare qui per andare alla sezione Riferimenti</sup> An estimated 4 billion dollars is expended annually on patients with CAP, <sup>8 Dans P.E., Charache P., Fahey M. , e al. Management of pneumonia in the prospective payment era: A need for more clinician and support service interaction Arch Intern Med 1984 ;  144 : 1392-1397

Cliccare qui per andare alla sezione Riferimenti, 16 Garibaldi R.A. Epidemiology of community-acquired respiratory tract infections in adults: Incidence, etiology, and impact Am J Med 1985 ;  78 : 32-37  [cross-ref]

Cliccare qui per andare alla sezione Riferimenti 20 La Force F.M. Community-acquired lower respiratory tract infections: Prevention and cost control strategies Am J Med 1985 ;  78 : 52-57  [cross-ref]

Cliccare qui per andare alla sezione Riferimenti, 27 Medicare and Medicaid statistical supplement Health Care Finance Rev 1995 ;  16 :

Cliccare qui per andare alla sezione Riferimenti</sup> with inpatient therapy costing as much as 20 times that of outpatient antimicrobial therapy.

There is substantial variability in hospital admission rates for adults with CAP, <sup>25 Maryland Department of Health Mental Hygiene, Office of Policy Analysis and Program Evaluation, Division of Medical Practice Patterns Analysis Variations in the use of medical and surgical services by the Maryland population  Rockville, MD: Maryland Department of Health Mental Hygiene (1986). 

Cliccare qui per andare alla sezione Riferimenti, 26 McMahon L.F., Wolfe R.A., Tedeschi P.J. Variation in hospital admissions among small areas: A comparison of Maine and Michigan Med Care 1989 ;  27 : 623-631  [cross-ref]

Cliccare qui per andare alla sezione Riferimenti 31 Roos N.P., Wennberg J.E., McPherson K. Using diagnosis-related groups for studying variations in hospital admissions Health Care Finance Rev 1988 ;  9 : 53-62

Cliccare qui per andare alla sezione Riferimenti, 36 Wennberg J.E., Frieman J.L., Culp W.J. Are hospital services rationed in New Hampshire or over-utilized in Boston? Lancet 1987 ;  1 : 1185-1189  [cross-ref]

Cliccare qui per andare alla sezione Riferimenti</sup> suggesting that clinicians use inconsistent criteria when making the initial site-of-care decision. Some patients at low risk for a poor outcome may be hospitalized but could be safely treated with an initial course of outpatient therapy. Identification of these patients at the time of presentation could reduce admissions and associated health care costs without compromising patient outcomes.

Medical practitioners responsible for the initial site-of-care decision for low-risk patients with CAP consider several clinical and psychosocial factors as very important when selecting the initial site of care. <sup>11 Fine M.J., Hough L.J., Medsger A.R. , e al. The hospital admission decision for patients with community-acquired pneumonia Arch Intern Med 1997 ;  157 : 36-44

Cliccare qui per andare alla sezione Riferimenti</sup> Clinical factors very important in the hospitalization decision include comorbid illness, multilobar infiltrate, poor clinical appearance, and arterial hypoxemia. Conversely, good clinical appearance, normal respiratory status, ability to maintain oral intake, normal mental status, and normal or only mildly abnormal vital signs were very important in the decision to provide outpatient care. Psychosocial factors including patient reliability and adequacy of home support were also rated as very important in the initial site-of-care decision.

Evidence suggests that clinicians apply these factors in a manner that tends to overestimate patient risk of short-term mortality. <sup>11 Fine M.J., Hough L.J., Medsger A.R. , e al. The hospital admission decision for patients with community-acquired pneumonia Arch Intern Med 1997 ;  157 : 36-44

Cliccare qui per andare alla sezione Riferimenti</sup> Among patients with an observed 30-day mortality of less than 1%, practitioners estimated that 5% of outpatients and 41% of inpatients had an expected mortality exceeding 5%. Multivariate analysis revealed that patients with a physician-estimated risk of death in excess of 5% were 18 times more likely to be hospitalized. Physicians often overestimate the potential for short-term mortality and consequently opt for more intensive inpatient therapy.

The decision to hospitalize patients with CAP and at low risk of mortality may be at odds with patient preferences. Empirical evidence showed that 80% of a group of low-risk patients would have preferred outpatient-based care, and most were willing to pay approximately one week's worth of household income to be assured of this preference. <sup>6 Coley C.M., Yi-Hwei L., Medsger A.R. , e al. Preferences for home vs. hospital care among low-risk patients with community-acquired pneumonia Arch Intern Med 1996 ;  156 : 1565-1571

Cliccare qui per andare alla sezione Riferimenti</sup> Better risk assessment by clinicians could yield more highly valued care and ultimately reduce the costs associated with hospitalization for CAP. The author's review the current consensus guidelines and clinical prediction rules now available for assessing patient prognosis and selecting an appropriate initial site of care for adults presenting with CAP.