A study of COPD patients found that, on average, their exercise capacity declined over time and that just 5% enrolled in pulmonary rehabilitation, an intervention that has been shown to improve outcomes.
Exercise capacity is a routine concern for specialists who deal with chronic obstructive pulmonary disease (COPD). They discuss how to measure it, its impact on quality of life, the need for effective interventions to increase it, and how frustrating the issue is for patients and health care providers alike. Without effective COPD management, and often despite effective management, exercise capacity tends to decline over time. When this happens, overall health status declines as well. Declining exercise capacity is also linked to increasing health care costs, failing prognoses, and risk of death.
A team of researchers working under the auspices of Spain’s Phenotype and Course of COPD Study Group examined the relationship between hospital admissions and exercise capacity decline in patients with COPD. Their hypothesis was based on the fact that each hospitalization negatively affects functional status and health outcomes; patients suffer loss of muscle tone, spend more time in bed, and are exposed to the possibility of hospital-acquired morbidities.
The researchers enrolled 342 clinically stable COPD patients (92% male, average age 68 years) during their first hospitalization due to COPD exacerbation to look at clinical and functional variables. Approximately a third of participants were current smokers. The researchers measured participants' exercise capacity using the 6-minute walk distance (6MWD). The annual rate of change was calculated by subtracting follow-up 6MWD from baseline 6MWD and dividing by follow-up time (mean 1.7 years). In addition, the researchers tracked hospitalizations using centralized administrative databases.
The researchers reported their results
online on January 3, 2014, in the European Respiratory Journal
. Although around 20% of patients demonstrated increased exercise capacity during follow-up, on average the participants’ 6MWD declined approximately 21.9 meters per year. In addition, 153 (45%) patients were hospitalized at least once, half of whom were admitted for COPD-related causes.
Among patients admitted for COPD-related causes, 53% experienced clinically significant 6MWD loss, compared with 29% of those admitted for non-respiratory conditions. After adjusting for confounders, patients who had more than 1 hospitalization for any reason had average annual 6MWD declines that were 26.1 meters greater than those who were not hospitalized. Total duration of hospital stay and the time from hospital discharge to the second evaluation were unrelated to the annual 6MWD decline.
One especially significant finding was that just 5% of participants had enrolled in pulmonary rehabilitation programs at follow-up. Pulmonary rehabilitation, an intervention proven to reduce hospitalizations and deaths and improve quality of life for people with recent COPD flare-ups, is a critical step for patients that should be used routinely. Clinicians need to promote pulmonary rehabilitation for COPD patients who are hospitalized, ideally enrolling them within days of discharge.
Ms. Wick is a visiting professor at the University of Connecticut School of Pharmacy and a freelance writer from Virginia.