Disease Trajectories and Impact of One Moderate Exacerbation in Gold B COPD Patients

Figures & data

Table 1 Baseline Characteristics of Patients in GOLD B, Split into GOLD B0 and B1

	GOLD B0		GOLD B1		P-value
	n	%	n	%
Patients	4,545		3,908
Sex
Male	2,323	51.1	1,951	49.9	0.276
Female	2,222	48.9	1,957	50.1
Cohabitation status
Not cohabitating	2,398	52.8	1,918	49.1	<0.001
Cohabitating	2,147	47.2	1,990	50.9
Age (years)
Mean age (SD)	70.1 (10.2)		69.9 (10.2)		0.430
40–49	152	3.3	122	3.1	0.712
50–59	599	13.2	551	14.1
60–69	1,264	27.8	1,100	28.1
70–79	1,683	37.0	1,423	36.4
80+	847	18.6	712	18.2
mMRC score
2	2,556	56.2	2,143	54.8	0.422
3	1,347	29.6	1,189	30.4
4	642	14.1	576	14.7
FEV1 (% of predicted)
80+	185	4.1	127	3.2	0.114
50–79	1,722	37.9	1,436	36.7
30–49	1,904	41.9	1,691	43.3
<30	734	16.1	654	16.7
BMI (kg/m2)
<18	458	10.1	380	9.7	0.879
18–24	1,609	35.4	1,373	35.1
25–29	1,328	29.2	1,129	28.9
30–34	728	16.0	644	16.5
35+	422	9.3	382	9.8
Smoking status
Not current smoker	2,903	63.9	2,519	64.5	0.576
Current smoker	1,642	36.1	1,389	35.5
Baseline treatment*
No claims	1,376	30.3	966	24.7	<0.001
LAMA	561	12.3	440	11.3
LABA	163	3.6	150	3.8
LABA/ICS	727	16.0	709	18.1
LABA/LAMA	211	4.6	193	4.9
LABA/LAMA/ICS	1,507	33.2	1,450	37.1
Charlson Comorbidity Index (CCI)
Mean (SD)	0.36 (0.89)		0.36 (0.88)		0.7190

Note: *Medication claimed 4 months prior to index.

Abbreviations: SD, standard deviation; mMRC, modified Medical Research Council; FEV1, forced expired volume in the first second; BMI, body mass index; LAMA, long-acting muscarinic antagonists; LABA, long-acting beta-agonists; ICS, inhaled corticosteroids.

Table 2 Frequency of Moderate and Severe Exacerbations and Death During Each Year of Follow Up and Cumulated Number Events Over All Three Years for GOLD B0 and GOLD B1 Patients

	Year 1		Year 2		Year 3		Total Follow Up*
	n	%	n	%	n	%	n	%
GOLD B0
No exacerbations	1,996	43.9	1,785	39.3	1,477	32.5	681	15.0
1 moderate exacerbation	936	20.6	742	16.3	719	15.8	869	19.1
≥2 moderate exacerbations	502	11.0	470	10.3	398	8.8	619	13.6
≥1 Severe exacerbation	516	11.4	502	11.0	468	10.3	893	19.6
Dead	501	11.0	912	20.1	1,306	28.7	1,306	28.7
OCS censoring**	94	2.1	134	2.9	177	3.9	177	3.9
GOLD B1
No exacerbations	1,284	32.9	1,110	28.4	975	24.9	321	8.2
1 moderate exacerbation	894	22.9	742	19.0	619	15.8	653	16.7
≥2 moderate exacerbations	698	17.9	588	15.0	587	15.0	774	19.8
≥1 Severe exacerbation	537	13.7	563	14.4	455	11.6	888	22.7
Dead	403	10.3	783	20.0	1,121	28.7	1,121	28.7
OCS censoring	92	2.4	122	3.1	151	3.9	151	3.9
p-value	<0.001		<0.001		<0.001		<0.001

Notes: *Cumulated number of events over the three years. Events were counted hierarchical, so an individual will count in the group with most severe events (moderate – severe – dead). **Censoring due to development of an OCS-related diagnosis during follow up (Crohn’s disease [K50], ulcerative colitis [K51], rheumatoid arthritis [M05], emphysema [J43], bronchiectasis [J47], cystic fibrosis [E84] or malignancy [C00–97]).

Abbreviation: OCS, oral corticosteroid.

Table 3 Odds Ratio (OR) of Exacerbations and Death in GOLD B1 Compared with GOLD B0 in Year 1, Year 2 and Year 3 Separately and in All Three Years Combined

	Year 1	Year 2	Year 3	Total Follow Up^§
	OR (95% CI)	OR (95% CI)	OR (95% CI)	OR (95% CI)
1 moderate	1.48 (1.31–1.66)	1.60 (1.41–1.82)	1.29 (1.12–1.47)	1.58 (1.33–1.87)
≥2 moderate	2.13 (1.86–2.44)	2.00 (1.72–2.29)	2.19 (1.88–2.60)	2.60 (2.19–3.08)
≥1 severe	1.60 (1.39–1.84)	1.80 (1.56–2.08)	1.46 (1.25–1.70)	2.08 (1.76–2.45)
Dead*	1.26 (1.08–1.48)	1.42 (1.24–1.62)	1.32 (1.16–1.49)	1.85 (1.57–2.17)

Notes: ^§Cumulated number of events over the three years. Events were cumulated over the three-year period and counted hierarchical, so an individual with multiple events counted in the group with most severe events (moderate – severe – dead). All ORs are adjusted for age, sex, cohabitation status, comorbidity, BMI and smoking. All p-values comparing B0 and B1 were <0.05. *The number of dead patients was cumulated for all three years.

Figure 1 Odds ratio (OR) with 95% CI of exacerbations and death after 3-years follow up in GOLD B1 with GOLD B0 as reference. Analyses adjusted for age, sex, cohabitation status, comorbidity, BMI and smoking.

Abbreviation: OR, odds ratio.

Table 4 Risk of Exacerbation During the Three Year Follow Up, Accounting for Recurrent Events

	Hazard Ratio*	Lower 5% CI	Upper 95% CI	P-value
GOLD B group
B0	Ref
B1	1.214	1.181	1.248	<0.001
Age	1.004	1.003	1.006	<0.001
Sex
Male	Ref
Female	1.041	1.012	1.071	0.0051
Cohabitation status
Not cohabitating	Ref
Cohabitating	1.079	1.050	1.110	<0.001
mMRC symptom score
2	Ref
3	1.055	1.023	1.087	<0.001
4	1.145	1.100	1.191	<0.001
FEV1 (% predicted)
80+	Ref
50–79	1.074	0.984	1.173	0.1095
30–49	1.265	1.160	1.381	<0.001
<30	1.420	1.297	1.555	<0.001
BMI (kg/m^2)
<18	Ref
18–24	0.916	0.873	0.961	<0.001
25–29	0.875	0.832	0.920	<0.001
30–34	0.853	0.807	0.901	<0.001
35+	0.893	0.839	0.951	<0.001
Smoking
Smoking present	Ref
Never smoked	0.853	0.807	0.901	<0.001
Smoking earlier	0.893	0.839	0.951	<0.001
Comorbidity (CCI)	1.010	0.994	1.027	0.2306

Note: *Adjusted for age, sex, cohabitation status, comorbidity, BMI and smoking.

Abbreviations: CI, confidence Interval; mMRC, modified Medical Research Council; FEV1, forced expired volume in the first second; BMI, body mass index.