Can CAPTURE be used to identify undiagnosed patients with mild-to-moderate COPD likely to benefit from treatment?

Figures & data

Figure 1 The CAPTURE™ (COPD assessment in primary care to identify undiagnosed respiratory disease and exacerbation risk) questionnaire.

Notes: Scoring: No =0; Yes =1; Item 5: 0, 1, 2. Scores are summed. © Cornell University, University of Kentucky Research Foundation, and Evidera, Inc. All rights reserved.

Table 1 Demographic characteristics by groupa

Characteristic	n=160		p-value
	COPDb (n=73)	No COPDc (n=87)
Age (years)
Mean (SD)	65.2 (9.1)	58.1 (10.5)	<0.0001
Range	49–85	40–88
Sex, n (%) male	40 (55)	26 (30)	0.0014
Ethnic background, n (%)
Not Hispanic or Latino	68 (99)	84 (99)	1.000
Racial background, n (%)d
White	66 (90)	73 (84)	0.2250a
Non-white	7 (10)	14 (16)
Employment, n (%)
Employed (full- or part-time)	15 (21)	55 (63)	<0.0001
Not employed	58 (79)	32 (37)
Retired	37 (51)	22 (25)
Disabled	18 (25)	3 (3)
Otherse	3 (4)	7 (8)
Education status, n (%)			0.0006
High school or less	36 (49)	18 (21)
Some college, vocational training	14 (19)	22 (25)
College degree or more	23 (32)	47 (54)

Notes:

a English-speaking with informed consent and spirometry.

b COPD, FEV₁ 60%–80% predicted, and no history of exacerbations >12 months.

c No known diagnosis or treatment for COPD and FEV₁/FVC ≥0.70.

d Subject self-identified; American Indian or Alaskan Native (1,1), Asian (0,1), Black or African American (11, 5), and others (2,0).

e Others: homemaker, unemployed, and not specified.

Abbreviation: FEV₁, forced expiratory volume in 1 second.

Table 2 Clinical characteristics by groupa

Characteristic	n=160		p-value
	COPDb (n=73)	No COPDc (n=87)
Smoking history, n (%)			<0.0001
Never or <100 cigarettes	2 (3)	51 (59)
Former	48 (66)	28 (32)
Current	23 (32)	8 (9)
Spirometry
FEV1, median	2.0	2.6	<0.0001
Mean (SD)	2.1 (0.6)	2.6 (0.7)
FEV1% predicted	70.0	93.0	<0.0001
Mean (SD)	74.0 (12.4)	89.7 (14.6)
FEV1/FVC, mean (SD)	0.6 (0.1)	0.8 (0.1)	<0.0001
Peak flow (PEF)	316.1 (102.86)	403.5 (109.00)	<0.0001
mMRC dyspnea scale (0–4 scale)
Median	2	1	<0.0001
Mode (n, %)	1 (34; 46)	0 (71; 82)
mMRC >2	20 (28)	5 (6)
CAT™ (0–40 scale)
Median	15.0	4.0	<0.0001
Mean (SD)	15.6 (8.0)	5.5 (5.4)
CAT >10, n (%)	57 (78)	13 (15)	<0.0001
mMRC >2 or CAT >10, n (%)	57 (78)	15 (17)	<0.0001
mMRC >2 and CAT >10, n (%)	20 (28)	3 (3)	<0.0001
Comorbid conditions (any), n (%) yes	73 (100)	76 (87)	0.0010
Self-report activity on most days, n (%)			0.0524
Sit, lie down, walk around home	38 (52)	32 (37)
Very active or exercise	35 (48)	55 (63)

Notes:

a English-speaking subjects with informed consent and spirometry.

b COPD, FEV₁ 60%–80% predicted, and no history of exacerbations >12 months.

c No known diagnosis or treatment for COPD and FEV₁/FVC ≥0.70.

Abbreviations: CAT, COPD Assessment Test; FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity; mMRC, modified Medical Research Council dyspnea scale; PEF, peak expiratory flow.

Table 3 Performance properties for questionnaire, PEF, and CAPTURE for differentiating COPD from no COPD

A
Milder COPDa (n=73) versus no COPDb (n=87)
Property	Questionnaire	PEFc		CAPTUREd
	Score >2	350/250 threshold	450/350 threshold	350/250 threshold	450/350 threshold
Sensitivity (%)	83.6	38.4	83.6	39.7	71.2
Specificity (%)	67.8	90.8	66.7	93.1	83.9
Error (%)	25.0	33.1	25.6	31.3	21.9
B
Severe, high-risk COPDa (n=186) versus no COPDb (n=87)^Citation1
Property	Questionnaire	PEFc	CAPTUREd
	Score >2	350/250 threshold	350/250 threshold
Sensitivity (%)	95.7	88.0	89.7
Specificity (%)	67.8	90.8	93.1
Error (%)	13.2	11.1	9.2
C
Full range of COPDa (n=259) versus no COPDb (n=87)
Property	Questionnaire	PEFc		CAPTUREd
	Score <2	350/250 threshold	450/350 threshold	350/250 threshold	450/350 threshold
Sensitivity (%)	92.3	73.9	94.2	75.5	88.0
Specificity (%)	67.8	90.8	66.7	93.1	83.9
Error (%)	13.9	21.8	12.8	20.1	13.0

Notes:

a (A) COPD, FEV₁ 60–80% predicted and no history of exacerbations >12 months;

b No known diagnosis or treatment for COPD and FEV₁/FVC ≥ 0.70;

c Peak expiratory flow (PEF) rate, liters per minute (L/min), thresholds: males/females;

d CAPTURE = Questionnaire + PEF.

a (B) COPD, FEV₁ < 60% predicted or exacerbation risk;

b No known diagnosis or treatment for COPD and FEV₁/FVC ≥ 0.70;

c Peak expiratory flow (PEF) rate, liters per minute (L/min), thresholds: males/females;

d CAPTURE = Questionnaire + PEF.

a (C) Medical diagnosis and treatment for COPD; FEV₁/FVC < 0.70;

b No known diagnosis or treatment for COPD and FEV₁/FVC ≥ 0.70;

c Peak expiratory flow (PEF) rate, liters per minute (L/min), thresholds: males/females (n=344);

d CAPTURE = Questionnaire + PEF.

Abbreviations: CAPTURE, COPD Assessment in Primary Care to Identify Undiagnosed Respiratory Disease and Exacerbation Risk; FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity; PEF, peak expiratory flow.

Figure 2 ROC and AUC by group.

Notes: (A) milder^a (n=73) versus No COPD^b (n=87); (B) severe, high-risk COPD^c (n=186) versus no COPD^d (n=87); (C) all COPD^e (n=259) versus no COPD^f (n=87). ^aCOPD, FEV₁ 60%–80% predicted and no history of exacerbations >12 months. ^bNo known diagnosis or treatment for COPD and FEV₁/FVC ≥0.70. ^cFEV₁ <60% or exacerbation risk. ^dNo known diagnosis or treatment for COPD and FEV₁/FVC ≥0.70.^{1 e}Medical diagnosis and treatment for COPD; FEV₁/FVC <0.70. ^fNo known diagnosis or treatment for COPD and FEV₁/FVC ≥0.70.
Abbreviations: AUC, area under the curve; CAPTURE™, COPD Assessment in Primary Care to Identify Undiagnosed Respiratory Disease and Exacerbation Risk; FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity; PEF, peak expiratory flow; ROC, receiver operating characteristics.

Table S1 Demographic characteristics of former smokers (N=76) by group

Characteristic	Former smokers (N=76)		p-value
	COPDb (n=48)	No COPDc (n=28)
Age (years)
Mean (SD)	67.4 (7.9)	62.0 (11.1)	0.0284
Range	51–85	40–88
Sex, n (%) male	24 (50)	10 (36)	0.2270
Ethnic background, n (%)
Not Hispanic or Latino	46 (98)	28 (100)	1.000
Racial background, n (%)d
White	44 (92)	25 (89)
Non-white	4 (8)	3 (11)	0.7039
Employment, n (%)
Employed (full- or part-time)	10 (21)	10 (21)	0.0052
Not employed/otherse	38 (79)	38 (79)
Education status, n (%)
High school or less	22 (46)	22 (46)	0.0934
Some college, vocational training	9 (19)	9 (19)
College degree or more	17 (35)	17 (35)

Notes:

a English-speaking with informed consent and spirometry;

b COPD, FEV₁ 60%–80% predicted and no history of exacerbations >12 months;

c No known diagnosis or treatment for COPD and FEV₁/FVC ≥0.70;

d Subject self-identified; non-white: American Indian or Alaskan Native (1, 1), Asian (0, 1), Black or African American (1, 2), others (1, 0).

e Others: homemaker, unemployed, and not specified.

Abbreviations: FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity.

Table S2 Clinical characteristics of former smokers (N=76) by group

Characteristic	COPDb (n=48)	No COPDc (n=28)	p-value
Spirometry, mean (SD)
FEV1, median	1.9	2.4	0.0023
Mean (SD)	2.0 (0.6)	2.5 (0.7)
FEV1% predicted, median	68.0	85.0	0.0020
Mean (SD)	73.5 (13.2)	85.0 (17.3)
FEV1/FVC	0.60 (0.06)	0.78 (0.06)	<0.0001
Peak flow (PEF)	320.9 (114.7)	396.3 (85.0)	0.0035
mMRC (0–4 scale)
Median	1	0	<0.0001
Mode (n, %)	1 (24, 51)	0 (25, 89)
mMRC >2, n (%)	12 (26)	1 (4)	0.0243
CAT™
Median	15.0	5.0	<0.0001
Mean (SD)	14.5 (6.6)	5.5 (4.7)
CAT >10, n (%)	38 (79)	5 (18)	<0.0001
mMRC >2 and CAT >10, n (%)	12 (26)	1 (4)	0.0243
mMRC >2 or CAT >10, n (%)	38 (79)	5 (18)	<0.0001
Comorbid conditions (any), n (%), yes	48 (100)	25 (89)	0.0466
Self-report activity on most days, n (%)
Sit, lie down, walk around home	26 (54)	10 (36)	0.1202
Very active or exercise	22 (46)	18 (64)

Notes:

a English-speaking subjects with informed consent and spirometry;

b COPD, FEV₁ 60%–80% predicted and no history of exacerbations >12 months;

c no known diagnosis or treatment for COPD and FEV₁/FVC ≥0.70.

Abbreviations: CAT, COPD Assessment Test; FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity; GOLD, Global Initiative for Chronic Obstructive Lung Disease; mMRC, modified Medical Research Council dyspnea scale.

Table S3 Performance of the questionnaire, PEF, and CAPTUREc for differentiating COPDa (n=48) from No COPDb (n=28) in former smokers (N=76)

Property	Questionnaire	PEFc		CAPTUREc (Questionnaire +PEF)
	Score >2	350/250 threshold	450/350 threshold	350/250 threshold	450/350 threshold
Sensitivity (%)	87.5	33.3	81.3	39.6	70.8
Specificity (%)	67.9	92.9	57.1	96.4	85.7
Error (%)	19.7	44.7	27.6	39.5	23.7

Notes:

a COPD, FEV₁ 60%–80% predicted, and no history of exacerbations >12 months;

b no known diagnosis or treatment for COPD and FEV₁/FVC ≥ 0.70.

c PEF rate (L/min), thresholds: males/females.

Abbreviations: FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity; PEF, peak expiratory flow.

Table S4 Performance properties of PEF thresholds for differentiating milder cases of COPDa from patients without COPDb by sex

Males (n=66)
Property	PEF threshold (L/min)c
	350	375	400	425	450d	475	500
Sensitivity (%)	37.5	52.5	65.0	80.0	80.0	82.5	85.0
Specificity (%)	88.5	88.5	80.8	69.2	65.4	53.8	50.0
Error (%)	42.4	33.3	28.8	24.2	25.8	28.8	28.8
Females (n=94)
Property	PEFc threshold (L/min)
	250	275	300	325	350d	375
Sensitivity (%)	39.4	66.7	69.7	75.8	87.9	93.9
Specificity (%)	91.8	86.9	85.2	80.3	67.2	42.6
Error (%)	26.6	20.2	20.2	21.3	25.5	39.4

Notes:

a COPD, FEV₁ 60%–80% predicted and no history of exacerbations >12 months.

b No known diagnosis or treatment for COPD and FEV₁/FVC ≥0.70.

c PEF rate, L/min.

d Selected threshold.

Abbreviations: FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity; PEF, peak expiratory flow.

Table S5 Prevalence of dyspnea and health status by CAPTURE™ Responsea in patients with COPDb (N=73)

Characteristic	CAPTURE (PEF 350/250)c Diagnostic testing recommended			CAPTURE (PEF 450/350)d Diagnostic testing recommended
	Yes, n=29 (40%)	No, n=44 (60%)	p-levele	Yes, n=52 (70%)	No, n=21 (30%)	p-levele
mMRC >2, n (%)	12 (43)	8 (18)	0.0227	19 (37)	1 (5)	0.0042
CAT™ >10, n (%)	26 (90)	31 (70)	0.0817	45 (86)	12 (57)	0.0060
mMRC >2 and CAT >10, n (%)	12 (43)	8 (18)	0.0227	19 (37)	1 (5)	0.0042

Notes:

a Questionnaire+PEF results suggest that further diagnostic evaluation is warranted (yes/no).

b COPD, FEV₁ 60%–80% predicted, and no history of exacerbations >12 months.

c Sensitivity=39.7%; specificity=93.1%; error=31.3% for milder patients versus no COPD.

d Sensitivity=71.2%; specificity=83.9%; error=21.9% for milder patients versus no COPD.

e Chi-square (χ²) or Fisher’s exact (cell n<5).

Abbreviations: CAT, COPD Assessment Test; FEV₁, forced expiratory volume in 1 second; mMRC, modified Medical Research Council dyspnea scale; PEF, peak expiratory flow.

MartinezFManninoDLeidyNKA new approach for identifying patients with undiagnosed chronic obstructive pulmonary diseaseAm J Respir Crit Care Med2017195674875627783539

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