Exercise is part of many programs to help patients with chronic obstructive pulmonary disease (COPD) breathe more easily. However, it can be hard to tell how much exercise these patients are getting.
Pulmonary rehabilitation is a program to help COPD patients improve symptoms and quality of life. It usually involves training on breathing techniques, exercise, education and counseling. One way to see if pulmonary rehabilitation is helping patients is to measure levels of daily physical activity.
In a recent study, researchers wanted to see how the use of pedometers (motion sensors that measure steps taken) related to daily physical activity in patients with COPD.
Results showed that daily physical activity, or the amount of steps taken per day, increased after patients underwent pulmonary rehabilitation and started wearing a pedometer.
Patients with more severe COPD took fewer steps per day than those with less severe disease. Physical activity levels varied with every patient, depending on the status of their COPD, weather and their daily schedule.
The study also showed that the use of pedometers was associated with improved exercise tolerance and quality of life.
The study was conducted by Nicoleta Bertici and fellow researchers at the University of Medicine and Pharmacy Victor Babe in Romania.
The research included 74 older patients with COPD in stages II, III and IV. COPD stage II is when symptoms, such as moderate cough and shortness of breath, start to appear. Stage IV - the last stage of COPD - is when symptoms are at their worst.
Using pedometers, Bertici and colleagues measured participants' daily physical activity for a period of seven days before and six months after a pulmonary rehabilitation program. The researchers also measured physical activity in a group of 21 patients with stable COPD who did not do the pulmonary rehabilitation program.
Results showed that the amount of steps taken per day varied widely among all the patients in the study, with a minimum of 964 steps per day and a maximum of 17,420 steps.
On average, patients with COPD stage IV had the lowest levels of physical activity, with an increase from 2,476 to 3,112 steps per day. Still, these patients had the highest increase over six months of pulmonary rehabilitation. In other words, these patients with severe COPD had the most improvement in daily physical activity.
Patients with COPD stage III increased daily physical activity by 597 steps per day, starting at an average of 5,627 steps per day and ending with 6,224 steps per day.
Patients with COPD stage II had the lowest increase in daily physical activity, starting at an average of 8,724 steps per day and ending at 9,264 steps per day - an increase of 540 steps per day.
According to the authors, patients with COPD stage II had the lowest increase probably because they already had the best levels of daily physical activity.
The researchers also found a link between the use of pedometers and the six-minute walk test (6MWT) and St. George's Respiratory Questionnaire. The 6MWT is used to measure exercise tolerance in patients with COPD. St. George's Respiratory Questionnaire measures health status of patients with chronic airflow limitation. It may give doctors and researchers an idea of COPD patients' symptom levels, disease activity and disability.
"Daily physical activity decreased with increasing COPD stage. It is fluctuant from subject to subject, depending on the clinical status, body mass index (a measure of body fat), weather/season, profession and daily schedule. Wearing pedometers is very easy and motivational, provided that patients realize that they are being 'watched,'" the authors wrote.
Because all these factors play a role in levels of physical activity, the authors said it can be difficult to objectively measure and establish recommended physical activity levels for each stage of COPD.
"But, at an individual level, these simple instruments (pedometers) proved their utility, allowing self-monitoring. We suggest that a 10 percent decrease in average daily physical activity should be taken as an alarming signal for the outcome of these patients," the authors concluded.
The study was published February 5 in Multidisciplinary Respiratory Medicine. The authors declared that they had no competing interests.