Objectively Quantifying the Shrinking Worlds of People With Chronic Dyspnea: A National, Online Survey

Chronic dyspnea is subjective but with objective (measurable) consequences. It is often poorly assessed because people have modified their lifestyles to avoid exertion that generates dyspnea.

This study sought any relationship between respondents' self-reported long-term breathlessness limiting exertion (hereafter chronic dyspnea) and distance travelled from the room in which they slept, frequency of mobilizing, and any assistance required.

This was a national, cross-sectional, online survey of 10,033 Australian adults conducted using the Qualtrics platform, reflecting the most recent national census. Demographic data were collected in addition to the modified Medical Research Council (mMRC) breathlessness scale, duration of dyspnea in people with mMRC ≥ 1 and the Life-Space Assessment scores (0-120 with higher scores reflecting three factors combined: frequency with which a person moves from the room in which they sleep, the furthest distance they achieve and whether they need assistance to achieve this). A regression model adjusted for age, sex, rurality, socio-economic status, and smoking.

A total of 8181 respondents had valid data: mean age 46.0 years (standard deviation ± 18.6); 29.3% mMRC ≥ 1, with more women reporting more intense dyspnea. Respiratory conditions were the most prevalent underlying cause. Using ANOVA, mean Life-Space Assessment scores reduced significantly as dyspnea increased (mMRC 0, 69.2; mMRC 1, 59.1; mMRC 2, 47.1; mMRC 3-4, 38.9; P < 0.0001). The regression model revealed an association (P < 0.001) between dyspnea and Life-Space Assessment scores decreasing from mMRC 0 by a mean of 9.3 (standard error [SE] 0.83) to mMRC 1; 20.3 (SE 1.2) to mMRC 2; and 27.9 (SE 1.8) to mMRC 3-4.

Although potentially intuitive, this study quantified the association of people's reduced spatial footprints at each level of self-reported chronic dyspnea severity, reflecting their shrinking worlds.