Fast Fact and Concept #141: Prognosis in End-Stage COPD

Authors: Julie Wilson Childers, Bob Arnold and J Randall Curtis

Prognostic variables in COPD patients are not well described, thus decision making regarding when to move away from aggressive life-sustaining treatments is challenging. This Fast Fact will review currently available COPD prognostic.

Ambulatory COPD patients The forced expiratory volume in one second (FEV 1) has traditionally been used to assess COPD severity. A FEV 1 of less than 35% of the predicted value represents severe disease; 25% of these patients will die within two years and 55% by four years. A number of other studies have shown that age, low body mass index (BMI), and low PaO 2 were independent predictors that correlated to reduced survival time. A scale consisting of body mass index (BMI), exercise capacity, and subjective estimates of dyspnea, has been shown to help predict survival over 1-3 years (Celli 2004):

*MMRC dyspnea scale range from 0 (none) to 4 (4 dyspnea when dressing or undressing).

Note: these variables do not appear to help predict prognosis within six months of death.

Hospitalized COPD patients Mortality statistics vary for patients admitted with COPD exacerbation depending on age, functional status, co-morbidities, and physiological variables such as hypoxia and hypercarbia. Roughly 10% of patients admitted with a paCO 2 >50 will die during the index hospitalization, 33% will die within six months, and 43% die within one-year (Connors 1996). Patients with less severe COPD have lower in-hospital mortality rates (Patil 2003). COPD patients who require mechanical ventilation have an-hospital mortality of ~ 25% (Seneff 1995; Nevins 2001). Poor prognostic factors include: co-morbid illnesses, severity of illness (APACHE II score), low serum albumin and/or low hemoglobin. Previous mechanical ventilation, failed extubation, or intuba tionfor greater than 72 hours all increase mortality (Nevins 2001). In one study, patients ventilated more than 48 hours had a 50% one year survival; functional status and severity of illness were associated with short term mortality while age and co-morbidities were associated with one year mortality (Celli 2004).

NHPCO criteria for hospice admission in COPD include factors such as cor pulmonale and pO2 <55 while on oxygen, albumin < 2.5 gm/dl, weight loss of > 10%, progression of disease, and poor functional status. However, a study showed when using these factors, 50% of the patients were still alive at six months, implying that the NHPCO criteria have a limited role in predicting six month mortality and thus should be used with caution in determining hospice eligibility under the Medicare Hospice Benefit (Fox 1999).

Summary

COPD is a heterogeneous disease without a simple prognostic trajectory. For ambulatory patients, their age, degree of dyspnea, weight loss (BMI), functional status and FEV1 are relevant prognostic factors for predicting 1-3 year survival. For hospitalized patients, the same factors are relevant; in addition, the need for prolonged or recurrent mechanical ventilation is predictive of shorter prognosis.

1. Celli BR, Cote CG, Marin JM, et al. The body-mass index, airflow obstruction, dyspnea, and exercise capacity index in chronic obstructive pulmonary disease. New England Journal of Medicine. 2004 Mar 4;350(10):1005-12.
2. Connors AF Jr, Dawson NV, Thomas C, et al: Outcomes following acute exacerbation of severe chronic obstructive lung disease. The SUPPORT investigators (Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatments). Am J Respir Crit Care Med 154:959-967, 1996.
3. Fox E, Landrum-McNiff K, Zhong Z, Dawson NV, Wu AW, Lynn J. Evaluation of prognostic criteria for determining hospice eligibility in patients with advanced lung, heart, or liver disease. JAMA. 1999 Nov 3;282(17):1638-45.
4. Nevins ML, Epstein SK.. Predictors of outcome for patients with COPD requiring invasive mechanical ventilation. Chest 2001; 119:1840-9.
5. Plant PK, Owen JL, Elliott MW. Early use of non-invasive ventilation for acute exacerbations of chronic obstructive pulmonary disease on general respiratory wards: a multicentre randomised controlled trial. Lancet 2000;355:1931–1935.
6. M. G. Seneff; D. P. Wagner; R. P. Wagner; et al. Hospital and 1-year survival of patients admitted to intensive care units with acute exacerbation of chronic obstructive pulmonary disease. JAMA, Dec 1995; 274: 1852 - 1857.

Copyright/Referencing Information : Users are free to download and distribute Fast Facts for educational purposes only. Citation for referencing: Childers JW, Arnold R, Curtis JR . Prognosis in End Stage COPD. Fast Fact and Concept #141 August 2005. End-of-Life / Palliative Education Resource Center www.eperc.mcw.edu.

Fast Facts were edited by David Weissman MD, Palliative Care Center, Medical College of Wisconsin until January 2007.  For comments/questions write to the current editor, Drew Rosielle MD: drosiell@mcw.edu. The complete set of Fast Facts is available at EPERC: www.eperc.mcw.edu

Disclaimer: Fast Facts provide educational information, this information is not medical advice. Health care providers should exercise their own independent clinical judgment. Some Fast Fact information cites the use of a product in dosage, for an indication, or in a manner other than that recommended in the product labeling. Accordingly, the official prescribing information should be consulted before any such product is used.

Creation Date: 8/2005

Purpose: Self-Study Guide, Teaching

Audience(s)

ACGME Competencies: Med Knowledge, Patient Care, Systems Based Practice

Keyword(s): prognosis; chronic pulmonary diseases

Specific Disease and Organ System Category(s): Chronic pulmonary diseases