Aug. 9, 2004 -- The mind may have some power to help tame asthma.
Biofeedback is a system that uses electronic monitoring devices that feed information back to an individual to teach him or her to control body functions that normally happen automatically. An example of biofeedback would be the use of a heart rate monitor to control the heart's rapidly beating pulse when someone does a form of exercise.
Studies have shown that biofeedback may influence heart rate variability, which in turn may improve lung function and airway flow resistance seen in patients with asthma.
Researchers studied 94 adults with asthma. After stabilizing all the participants with an asthma-controlling medicine, researchers split them into four groups.
The first group used heart rate variability (HRV) biofeedback and breathing exercises. The second group just used HRV biofeedback. The third followed a placebo program with bogus content -- "subliminal suggestions designed to help asthma" plus biofeedback, and the fourth group received no treatment.
Participants in the first three groups attended 10 weekly biofeedback sessions and were asked to practice at home for 20 minutes twice daily. HRV biofeedback groups were sent home with a monitor that analyzed heart rate.
People in the HRV biofeedback groups were able to significantly reduce the amount of inhaled steroid medications they needed to control their asthma symptoms. HRV biofeedback groups showed an improvement in their asthma's severity.
The breathing exercises done by the first group didn't add any extra advantage, suggesting that the improvement was caused by the biofeedback alone.
The placebo and comparison groups did not show improvements in asthma severity.
"HRV biofeedback appears to be promising as an adjunctive treatment for asthma, and it appears to maintain the condition of asthma patients with a reduced dose of inhaled steroids," write the researchers in the journal CHEST.
Biofeedback was explored as a complement to other treatments, not a replacement for medications.
More study is needed before biofeedback is recommended to people with asthma. In particular, the researchers want to know if the results hold for a longer time and how biofeedback works. Until then, they voice caution about putting their findings into practice.