What Are the Survival Rates for Patients With COPD?

Answering the most common question

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The most common question patients ask after being diagnosed with a disease is an easy one to guess:  how long do I have to live?  Although some diseases have very predictable courses, COPD is not one of them.  Unfortunately, there are many things that weigh into a determination of how long patients live, that even clinical experts have difficulty predicting survival in COPD patients.  This article will discuss five basic questions that may help when trying to determine life expectancy, although it is important to keep in mind that every patient is an individual and there is no hard-and-fast rule for how long a patient with COPD might live.

The factors that need to be accounted for include:

  • Are you still smoking?  Patients who continue to smoke despite a diagnosis of COPD have a worse prognosis (1). A large research study that monitored patients and their outcomes over 15 years, called the Lung Health Study, established that quitting smoking lowered the rate with which lung function declined.  This means that for patients who continue to smoke will likely have shorter lifespans than those who quit smoking. 
  • How severe is your COPD?  The severity of COPD is determined by pulmonary function tests, (aka spirometry).  A common classification system is the GOLD (Global Obstructive Lung Disease) Criteria.  The GOLD guidelines classify COPD severity into four stages (mild, moderate, severe, very severe).  The higher the stage, the worse the long-term outcome.   One study found that 24% of patients with very severe COPD died within three years of the study.  15% of the patients with severe COPD and 11% of the patients with moderate COPD died within three years of that study (2).  The trends in lung function also signal patients who have poorer prognoses.  Many clinicians monitor lung function number called “FEV-1” that is obtained during spirometry or pulmonary function testing.  If this number starts steadily declining, this may be a sign that a patient is doing poorly.
  • Are you able to exercisePatients who survive the longest with COPD are ones who are able to exert themselves (called ‘exercise capacity’) without profound shortness of breath.  The better one’s exercise capacity is, the longer patients tend to live with COPD.  Clinicians use various symptom severity scores to assess and track patient symptoms over time.  The BODE index is one such score.  The BODE index is scored on a 10-point scale and takes into account lung function (the FEV-1), the results of a 6-minute walk test, body mass index (BMI) and the feelings of shortness of breath.  Higher scores on the BODE index places patients at higher risk of death.
  • How many exacerbations and/or hospitalizations due to COPD do you have per year? Patients whose COPD does not flare up in the form of exacerbations and those who do not frequently require hospitalization tend to live longer than patients who have recurrent exacerbations or hospitalizations.  In general, the number of exacerbations/hospitalizations are related to the severity of COPD, but not always.  Patients who have mild COPD but are frequently hospitalized may have similar prognoses to those with very severe COPD.  Patients who are hospitalized more than 2-3 times per year confer a larger risk of death than those who are hospitalized less often.
  • What other medical problems do you have? Many patients with COPD also have other medical problems.   Patients with COPD may have lung cancer, obstructive sleep apnea, cardiovascular disease, obesity, osteoporosis and others.  These conditions may occur in patient with any level of COPD severity.  Treating and/or controlling these other conditions is important to improve survival and decrease hospitalizations.      

    The Bottom Line:

    • Survival of patients with COPD is very variable.  It is almost impossible to predict how long a patient will live with COPD.
    • Factors that worsen the prognosis of COPD include: severity of disease, decrease in exercise capacity, number of exacerbations and/or hospitalizations, other medical problems and smoking status.
    • Patients with COPD who quit smoking live longer than patients with COPD who continue to smoke.

    REFERENCES

    1. Anthonisen NR. Lessons from the Lung Health Study. Proceedings of the American Thoracic Society 2004;1:143-5.
    2. The TORCH study “Toward a Revolution in COPD Health.
    3. Celli et. all.  The Body-Mass Index, Airflow Obstruction, Dyspnea, Exercise Capacity Index in COPD. NEJM,  350;  10, 2004.
    4. GOLD Guidelines- Global Strategy for the Diagnosis, Management, and prevention of COPD; 2014

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