Characteristics Associated with Accelerated Lung Function Decline in a Primary Care Population with Chronic Obstructive Pulmonary Disease

Figures & data

Figure 1 Study design.

Table 1 Baseline Characteristics of Study Participants in Both FEV₁ and FVC Cohorts

Baseline Characteristics	FEV1 Cohort N (%) or Median (IQR) N=72,683	FVC Cohort N (%) or Median (IQR) N=50,649
Patient demographics
Age	67 (60–75)	67 (60–75)
Gender (male)	39,266 (54.0)	27,389 (54.1)
Smoking status
Smoker	43,902 (60.4)	30,584 (60.4)
Ex-smokers	26,781 (39.6)	20,065 (39.)
Index of Multiple Deprivation*
1 (most deprived)	10,897 (15.0)	7327 (14.5)
2	13,700 (18.9)	9375 (18.5)
3	14,455 (19.9)	10,178 (20.1)
4	16,085 (22.1)	11,398 (22.5)
5 (least deprived)	17,502 (24.1)	12,338 (24.4)
Symptoms
Breathlessness	11,997 (16.5)	17,052 (33.7)
Chronic cough	25,129 (34.6)	28,997 (57.3)
Sputum production	5104 (7.0)	6501 (12.8)
Comorbidities
Anxiety	5181 (7.1)	3763 (7.4)
Depression	5818 (8.0)	4015 (7.9)
GORD	3744 (5.2)	2715 (5.4)
Body Mass Index *
Underweight	2353 (4.1)	1908 (4.1)
Normal	20,445 (35.5)	15,713 (33.4)
Overweight	20,017 (34.8)	16,165 (34.4)
Obese	14,49 (25.6)	13,230 (28.1)
Bronchiectasis	1869 (2.6)	1404 (2.8)
Lung cancer	348 (0.5)	237 (0.5)
Heart failure	4532 (6.2)	3086 (6.1)
Stroke	2757 (3.8)	1818 (3.6)
Myocardial infarction	5030 (6.9)	3506 (6.9)
Asthma	21,855 (30.1)	18,718 (37.0)
COPD severity
mMRC dyspnoea*
0	8098 (20.8)	6252 (20.7)
1	15,887 (40.9)	12,440 (41.2)
2	9550 (24.6)	7411 (24.6)
3	4533 (11.7)	3532 (11.7)
4	787 (2.0)	543 (1.8)
Airflow obstruction*
Mild	18,267 (25.4)	13,398 (27.2)
Moderate	33,452 (46.5)	22,663 (46.0)
Severe	16,522 (22.9)	10,853 (22.0)
Very severe	3777 (5.2)	2407 (4.9)
AECOPD frequency in 1st year
None	30,178 (41.5)	20,790 (41.1)
1 moderate	17,665 (24.3)	12,286 (24.3)
2 moderate	9618 (13.2)	6782 (13.4)
≥3 moderate	11,339 (15.6)	8169 (16.1)
1 severe, any moderate	3126 (4.3)	2127 (4.2)
≥2 severe, any moderate	757 (1.0)	495 (1.0)
COPD medications
ICS combinations	38,615 (53.1)	28,089 (55.5)
Non-ICS combinations	34,068 (46.9)	22,560 (44.5)
Mean first FEV1 or FVC in L (SD)	1.7 (0.7)	2.7 (1.0)
Mean FEV1/FVC ratio*	0.6 (0.7)	0.6 (0.7)

Notes: *IMD: FEV₁ cohort=49,279, FVC cohort=34,795; BMI: FEV₁ cohort N=57,564, FVC cohort N=47,016; MRC dyspnoea: FEV₁ cohort N=38,855, FVC cohort N=30,178; Airflow obstruction FEV₁ N=72,018, FVC cohort N=49,321; FEV1/FVC ratio: FEV1 cohort N=49,601, FVC cohort N=49,601.

Abbreviations: GORD, gastro-oesophageal reflux disease; mMRC, modified Medical Research council; AECOPD, exacerbations of COPD; ICS, inhaled corticosteroid.

Figure 2 COPD patients included in the FEV₁ and FVC cohorts.

Figure 3 Distribution of the change in FEV₁ and FVC^{1. 1}Panel (A) shows the distribution in the change in FEV1 in 72,683 patients. Panel (B) shows the distribution in the change in FVC in 50,649 patients.

Table 2 Baseline Characteristics Associated with Accelerated Decline. Numbers are Adjusted OR (95% CI)

	Odds of Being a Fast FEV1 Decliner (OR (95% CI)) N=30,609	P value	Test for Trend	Odds of Being a Fast FVC Decliner (OR (95% CI)) N=28,021	P value	Test for Trend
Age	1.01 (1.00–1.01)	0.001		1.03 (1.03–1.03)	<0.001
Gender (Males)	0.91 (0.83–1.00)	0.050		0.48 (0.45–0.51)	<0.001
Current smoking	1.15 (1.07–1.23)	<0.001		1.03 (0.98–1.09)	0.268
IMD
1 (most deprived)	Ref	Ref	0.015	Ref	Ref	0.016
2	1.00 (0.90–1.11)	0.976		1.01 (0.93–1.10)	0.787
3	1.04 (0.93–1.16)	0.482		0.98 (0.90–1.07)	0.609
4	1.01 (0.91–1.12)	0.878		0.98 (0.90–1.06)	0.616
5 (least deprived)	1.15 (1.04–1.27)	0.009		1.15 (1.06–1.25)	0.001
Breathlessness	1.27 (1.15–1.39)	<0.001		1.03 (0.98–1.09)	0.248
Cough	1.07 (0.99–1.16)	0.079		0.91 (0.86–0.96)	0.001
Sputum	1.06 (0.92–1.21)	0.424		1.13 (1.05–1.22)	0.001
Asthma	0.93 (0.86–1.01)	0.079		1.05 (0.99–1.12)	0.081
Myocardial infarction	0.94 (0.84–1.06)	0.311		1.05 (0.95–1.16)	0.304
Stroke	1.10 (0.95–1.28)	0.206		1.05 (0.92–1.20)	0.459
Heart failure	0.88 (0.77–1.00)	0.057		1.12 (1.01–1.25)	0.036
Lung cancer	1.19 (0.78–1.12)	0.419		0.95 (0.66–1.36)	0.786
Bronchiectasis	0.91 (0.74–1.12)	0.364		1.18 (1.01–1.38)	0.036
GORD	0.96 (0.84–1.10)	0.552		1.02 (0.92–1.14)	0.691
Anxiety	0.93 (0.82–1.05)	0.231		1.07 (0.97–1.19)	0.169
Depression	1.09 (0.97–1.22)	0.150		1.14 (1.03–1.25)	0.012
Body mass index
Normal	Ref	Ref	<0.001	Ref	Ref	<0.001
Underweight	1.16 (0.98–1.37)	0.084		1.27 (1.17–1.45)	<0.001
Overweight	0.85 (0.79–0.91)	<0.001		0.89 (0.84–0.95)	<0.001
Obese	0.84 (0.78–0.91)	<0.001		0.90 (0.84–0.96)	0.001
mMRC
0	Ref	Ref	0.947	Ref	Ref	0.556
1	1.02 (0.94–1.11)	0.676		1.06 (0.99–1.13)	0.107
2	1.15 (1.05–1.27)	0.003		1.23 (1.14–1.33)	<0.001
3	1.20 (1.07–1.35)	0.003		1.30 (1.18–1.43)	<0.001
4	1.15 (0.90–1.48)	0.272		1.39 (1.14–1.70)	0.001
Airflow obstruction
Mild	Ref	Ref	<0.001	Ref	Ref	<0.001
Moderate	0.74 (0.67–0.81)	<0.001		1.07 (1.01–1.14)	0.031
Severe	0.91 (0.77–1.07)	0.232		1.19 (1.10–1.29)	<0.001
Very severe	0.65 (0.47–0.90)	0.010		1.47 (1.27–1.69)	<0.001
AECOPD frequency
0	Ref	Ref	0.001	Ref	Ref	0.188
1 moderate, 0 severe	1.04 (0.96–1.12)	0.322		1.07 (1.01–1.14)	0.028
2 moderate, 0 severe	1.09 (0.99–1.20)	0.079		1.03 (0.95–1.12)	0.443
≥3 moderate, 0 severe	1.18 (1.07–1.29)	0.001		1.15 (1.07–1.24)	<0.001
1 severe, any moderate	1.10 (0.93–1.29)	0.277		1.28 (1.12–1.45)	<0.001
≥2 severe, any moderate	1.11 (0.77–1.60)	0.576		1.55 (1.19–2.02)	0.001
COPD medication
Non-ICS combinations	Ref	Ref		Ref	Ref
ICS-combinations	1.11 (1.04–1.19)	0.002		1.04 (0.99–1.10)	0.142

Notes: For variables breathless, cough, sputum, asthma, MI, stroke, HF, lung cancer, bronchiectasis, GORD, anxiety and depression, the reference groups are not having the symptom/comorbidity. For smoking status, the reference group is ex-smoking patients.

Abbreviations: IMD, Index of Multiple Deprivation; GORD, gastro-oesophageal reflux disease; mMRC, modified Medical Research council; AECOPD, exacerbations of COPD; ICS, inhaled corticosteroid.