Respiratory symptom perception differs in obese women with strong or mild breathlessness during constant load exercise.

Chest

PubMedID: 23989732

Bernhardt V, Babb TG. Respiratory symptom perception differs in obese women with strong or mild breathlessness during constant load exercise. Chest. 2014;145(2):361-9.
ABSTRACT BACKGROUND
During constant load exercise, some otherwise healthy obese women report substantially more dyspnea on exertion (DOE) than others. The objective of this study was to investigate whether qualitative differences exist between the sensations of dyspnea felt by these women.

METHODS
78 women were categorized based on their Ratings of Perceived Breathlessness (RPB, Borg 0-10 scale) after 6 minutes of 60W cycling. 34 women rated RPB=4 (+DOE) (34±7yr, 36±5BMI) and 22 women rated RPB=2 (-DOE) (32±7yr, 37±4BMI). 22 women rated RPB=3 (RPB=3) (34±7yr, 34±4BMI) and were grouped separately to allow for a better delineation of the +DOE and -DOE groups. After the exercise test, subjects were asked to pick three of fifteen statements that best described their respiratory sensations.

RESULTS
The +DOE and -DOE groups were differentially (p<0.05) characterized by the respiratory clusters "Breathing more" (82% of -DOE vs 41% of +DOE), "Shallow" (36% vs 6%), and "Heavy" (14% vs 53%). All four descriptors in the cluster "Work/Effort" were more frequently chosen by +DOE than -DOE women. Although relative exercise intensity was higher in the +DOE women (75±13% vs 67±10% of peakV.O2, 41±10 vs 31±8L/min as %MVV, 83±7 vs 76±7% of peak HR), none of these variables were significantly associated with RPB.

CONCLUSIONS
Not only is the intensity of dyspnea significantly different between these groups, but also the self-reported qualitative aspects of their dyspnea. +DOE women reported an increased sensation of the work of breathing relative to -DOE women, which may be associated with the elevated RPB.