outpatients with cardiorespiratory disease25 and the
Dyspnea-12 in patients with asthma26 and found that
the affective aspect of dyspnea can signiﬁcantly inﬂuence
the impact of dyspnea on health status, irrespective of
the intensity of breathlessness.
In those with PRISm, there was a strong, positive
association between higher values for the FEV1/FVC
ratio and dyspnea. For the PRISm group, a higher
FEV1/FVC ratio may reﬂect diminished lung
compliance due to interstitial lung disease and/or
respiratory system restriction due to obesity, which
could contribute to worse dyspnea. Conversely, the
association of dyspnea with the FEV1/FVC ratio was in
the opposite direction for those with asthma or COPD,
and a lower FEV1/FVC ratio correlated with worse
dyspnea, as expected.
Our study complements the literature by focusing on
adults with undiagnosed respiratory symptoms who
were randomly selected and recruited through active
case ﬁnding in the community. This increases the
generalizability of our results to a broader population.
Our dyspnea questions were derived from widely used
and validated respiratory health questionnaires, and
our dyspnea assessment measure is a weighted average
of responses to these validated questions.
Consequently, the measure has an immediate
interpretation in terms of the lived day-to-day
experience of individuals.
Our study has limitations. We did not undertake
reliability/reproducibility testing of our questionnaire.
The dyspnea impact assessment score was statistically
associated with increased health care utilization, lower
quality of life, and reduced work productivity; therefore,
by virtue of this analysis, our questionnaire has
construct validity. However, further attempts at external
validation of the questionnaire using an independent
data set would be important. Health care utilization
during the preceding 12 months was assessed on entry
into the study, and there is potential for impaired recall
of events. Our study may have missed asthma in some
participants because bronchial challenge testing was not
conducted on those who tested negative for airﬂow
obstruction or BD responsiveness. A previous study
showed that an additional diagnostic step incorporating
TABLE 8] Unadjusted and Adjusted Dyspnea Associations With Health Care Use
Measure
Unadjusted Adjusted
Dyspnea OR (95% CI) P Value Dyspnea OR (95% CI) P Value
In the past 12 mo, did you visit your general
practitioner or a nurse practitioner or another
physician at a walk-in clinic for any breathing
problems?
1.011 (1.007-1.014) < .001 1.011 (1.007-1.014) < .001
In the past 12 mo, did you visit an emergency
department for any breathing problems?
1.015 (1.009-1.021) < .001 1.015 (1.009-1.022) < .001
In the past 12 mo, were you hospitalized for any
breathing problems or respiratory illness?
1.021 (1.006-1.037) .006 1.023 (1.007-1.039) .005
Data are presented as OR (95% CI) withP values. Adjusted values are adjusted for age, sex, and BMI.
TABLE 9] Unadjusted and Adjusted Dyspnea Associations With Work Productivity (WPAI)
Measure
Unadjusted Adjusted
Dyspnea OR (95% CI) P Value Dyspnea OR (95% CI) P Value
Are you currently employed
(working for pay)?
0.995 (0.992-0.998) .002 0.993 (0.990-0.997) < .001
Measurea
Dyspnea Coefﬁcient
(95% CI) P Value
Dyspnea Coefﬁcient
(95% CI) P Value
Absenteeism 0.061 (0.040-0.083) <.001 0.066 (0.044-0.089) < .001
Presenteeism 0.334 (0.293-0.375) <.001 0.349 (0.306-0.392) < .001
Work productivity loss 0.368 (0.323-0.413) <.001 0.383 (0.336-0.430) < .001
Activity impairment 0.503 (0.463-0.544) <.001 0.501 (0.458-0.544) < .001
ORs and regression coefﬁcients are presented with 95% CIs andP values. Adjusted coefﬁcients are adjusted for age, sex, and BMI. WPAI¼ Work Pro-
ductivity and Activity Impairment questionnaire.
aMeasures calculated from WPAI questions.21
1306 Original Research [ 166#6 CHEST DECEMBER 2024 ]