However, 1,415 either did not attend or were unable to
complete adequate spirometry. Ultimately, 2,857 (67%)
of those eligible underwent both pre- and post-BD
spirometry.
Of these 2,857 participants, 2,090 (73.2%) had normal
spirometry, 265 (9.3%) had undiagnosed asthma, 330
(11.5%) had undiagnosed COPD, and 172 (6.0%) had
PRISm based on post-BD spirometry. Of the 595
individuals with spirometric evidence of asthma or
COPD, 253 were independently assessed by a
pulmonologist. In 245 of these 253 cases (97%), the
independent physician diagnosis agreed with the study
diagnosis of asthma or COPD.
Individuals in the COPD group were generally older
a n dm o r el i k e l yt ob em a l ec o m p a r e dw i t ha l lo t h e r
study groups (Table 1). All groups, including healthy
control participants, had mean BMIs in the overweight
o ro b e s er a n g e s .T h eP R I S mg r o u pw a sh e a v i e s tw i t ha n
average BMI of 34.7, and 22% of PRISm patients met
BMI criteria for morbid obesity. Compared with all
other groups, those with COPD were the most likely to
have active or previous tobacco use, with the highest
average total pack-years of 32.7. The control group had
the lowest number of people with active or previous
tobacco use.
Table 2 shows mean responses to the 15 dyspnea
questions for each disease classiﬁcation and presents
question weights (PCA scoring coefﬁcients) used for
calculating the dyspnea impact assessment.
Individuals with PRISm reported the highest dyspnea
impact, with a signiﬁcantly greater mean score (63.0;
95% CI, 59.5-66.4) than those with undiagnosed
asthma or COPD (Table 3). Those with undiagnosed
asthma or COPD had similar mean scores (56.6;
95% CI, 53.9-59.3 and 57.5; 95% CI, 55.1-59.9,
respectively), followed by those with normal
spirometry (51.8; 95% CI, 50.7-52.8). All four groups
reported signiﬁcantly more impactful dyspnea than
the control group (mean score, 13.8; 95% CI, 11.8-
15.7). Table 3 shows between-group differences in
mean dyspnea impact assessments for each pair of
disease outcomes. Figure 2 compares box plots of the
dyspnea impact assessment values across disease
classiﬁcations.
Table 4 presents the association of dyspnea with
patient-speci ﬁc risk factors. Dyspnea impact increased
with younger age, being female, higher BMI, higher
smoking and smoke exposure history, and total work
TABLE 2] (Continued)
Questions About Dyspnea From CAT and SGRQ
Control Group
(n ¼ 231)
Normal Spirometry
Group (n ¼ 2,090)
Asthma Group
(n ¼ 265)
COPD Group
(n ¼ 330)
PRISm Group
(n ¼ 172)
Q13 (weight¼ 0.132) My breathing makes it dif ﬁcult to do things such as
climbing up hills, carrying things up stairs, light
gardening such as weeding, dancing, bowling, orgolﬁng, %
85 45 9 6 9 7 4
Q14 (weight¼ 0.123) My breathing makes it dif ﬁcult to do things such as
carrying heavy loads, digging the garden or shoveling
snow, jogging, or walking at 5 km/h, playing tennis orswimming, %
13 65 71 78 81
Q15 (weight¼ 0.108) My breathing makes it dif ﬁcult to do things such as very
heavy manual work, running, cycling, swimming fast,
or playing competitive sports, %
17 74 79 85 88
Data are presented as mean (SD) for Q1, Q2, and Q3 (total), and Q3 to Q15 were presented to participants as yes or no questions, where percentages of participants who answered yes are shown. Question weights
(principal component analysis scoring coefﬁcients) used for calculating the dyspnea assessment are shown below individual questions. CAT¼ COPD Assessment Test; PRISm¼ preserved ratio impaired spirometry;
Q ¼ question; SGRQ ¼ St. George’s Respiratory Questionnaire.
1302 Original Research [ 166#6 CHEST DECEMBER 2024 ]