Socioeconomic circumstances and incidence of chronic obstructive pulmonary disease (COPD) in an urban population in Sweden

Figures & data

Table 1. Characteristics of the Malmö inhabitants aged 40–89 years and MPP cohort participants.

Malmö inhabitants (N = 117,479)
	Incident COPD (n = 2,877)	Non-COPD (n = 114,602)	p value
Age (mean ± SD)	65.7 ± 10.3	60.9 ± 3.3	<0.001
Age groups (%)
40–49	7.8	26.1
50–59	19.1	21.0
60–69	34.9	23.0
70–79	29.7	19.9
80–89	8.5	9.9
Sex (%)			<0.001
Women	52.5	55.4
Men	47.5	44.6
Annual income (SEK) (mean ± SD)	1091.6 ± 639.4	1316.9 ± 1969.3	<0.001
Income groups (mean ± SD)
Q1	473.4 ± 170.0	434.0 ± 190.6
Q2	933.9 ± 137.5	940.4 ± 140.4
Q3	1379.2 ± 130.3	1396.7 ± 132.9
Q4	2223.7 ± 735.1	2476.7 ± 3606.7
Housing status (%)			<0.001
Self-owned	46.8	55.7
Rented	49.7	40.3
Others	3.5	4.0
Marital status (%)			<0.001
Single	11.2	13.7
Married	48.7	54.9
Divorced	22.3	16.8
Widowed	17.9	14.6
Country of birth (%)			0.764
Swedish born	84.1	84.3
Foreign born	15.9	15.7
MPP (n = 27,358)
	Incident COPD	Non-COPD	p value
	(n = 2,294)	(n = 25,064)
Age (mean ± SD)	47.0 ± 6.7	44.4 ± 7.2	<0.001
Age groups (%)
<40	29.9	17.8
40–50	53.3	56.4
>50	16.7	25.9
Sex (%)			<0.001
Women	32.0	26.8
Men	68.0	73.2
Occupation (%)			<0.001
Low	70.7	61.6
Middle	12.1	18.0
High	5.4	10.4
Own company	6.7	7.0
Retired and others	5.1	3.0
Annual income (SEK) (mean ± SD) income groups (mean ± SD)	1000.8 ± 511.6	1127.4727.1	<0.001
Q1	497.5 ± 223.8	479.2 ± 235.6
Q2	919.4 ± 70.4	824.2 ± 69.9
Q3	1138.8 ± 68.9	1144.2 ± 69.4
Q4	1693.4 ± 659.7	1804.2 ± 1018.7
Marital status (%)			<0.001
Single	10.2	13.6
Divorced	19.3	12.8
Widowed	2.9	1.8
Married	67.7	71.7
Country of birth (%)			0.649
Swedish born	84.9	85.2
Foreign born	15.1	14.8
Smoking status (%)			<.001
Never smoker	9.9	37.3
Former smoker	9.5	18.1
Current smoker	80.6	44.6
BMI (mean ± SD)	24.2 ± 3.8	24.4 ± 3.5	<0.001
BMI groups (%)
<18.5	3.7	1.8
18.5–24.9	58.9	58.6
25–29.9	30.1	33.0
>30	7.3	6.7
Forced Expiratory volume in 1 sec (FEV1) (mean ± SD)	2.7 ± 0.9	3.3 ± 0.8	<0.001

Values expressed are means ± standard deviation (SD) or percentages.

Table 2. Incidence of COPD in relation to socioeconomic circumstances and other risk factors among the Malmö inhabitants aged 40–89 years (N = 117,479).

	Incident COPD
	N of COPD(per 1,000 p-y)	HR^a(95% CI)	p value
Annual income
Q4	400 (0.88)	Reference
Q3	704 (1.64)	1.70 (1.50–1.92)	<0.001
Q2	957 (2.58)	2.23 (1.97–2.53)	<0.001
Q1	816 (2.45)	2.10 (1.83–2.40)	<0.001
Housing status
Self-owned	1,345 (1.48)	Reference
Rented	1,430 (2.30)	1.41 (1.30–1.52)	<0.001
Marital status
Married	1,400 (1.53)	Reference
Single	322 (1.47)	1.06 (0.94–1.21)	0.342
Divorced	641 (2.28)	1.61 (1.46–1.78)	<0.001
Widowed	514 (3.01)	1.30 (1.16–1.46)	<0.001
Country of birth
Sweden	2,419 (1.83)	Reference
Foreign born	458 (1.72)	1.02 (0.92–1.13)	0.686
Age group
40–49	224 (0.43)	Reference
50–59	549 (1.44)	3.51 (3.00–4.11)	<0.001
60–69	1,005 (2.64)	6.30 (5.43–7.31)	<0.001
70–79	855 (3.62)	8.65 (7.40–10.12)	<0.001
80–89	244 (3.31)	8.19 (6.71–9.99)	<0.001
Sex
Women	1,510 (1.71)	Reference
Men	1,367 (1.94)	1.73 (1.60–1.88)	<0.001

^a Model including age, sex, marital status, annual income, housing status and country of birth P-y: person-years; HR: hazard ratio; CI: confidence interval.

Figure 1. Incidence of hospitalization for COPD in relation to occupation in the MPP cohort.

Figure 2. Incidence of hospitalization for COPD in relation to income in the MPP cohort.

Table 3. Incidence of COPD in the MPP cohort in relation to socioeconomic circumstances and other risk factors (n = 27,358).

	Incident COPD
		Model 1^a		Model 2^b
	N of COPD (per 1,000 p-y)	HR (95% CI)	p value	HR (95% CI)	p value
Occupation
High	124 (1.48)	Reference		Reference
Middle	278 (1.89)	1.23 (0.99–1.52)	0.056	1.13 (0.91–1.40)	0.268
Low	1,621 (3.30)	1.82 (1.49–2.12)	<0.001	1.35 (1.11–1.65)	0.003
Own company	153 (2.68)	1.40 (1.09–1.80)	0.007	1.21 (0.94–1.55)	0.134
Retired and others	118 (5.57)	2.36 (1.79–3.11)	<0.001	1.58 (1.20–2.07)	0.001
Annual income
Q4	418 (1.85)	Reference		Reference
Q3	571 (2.66)	1.20 (1.05–1.38)	0.006	1.06 (0.92–1.21)	0.360
Q2	681 (3.55)	1.53 (1.33–1.76)	<0.001	1.17 (1.01–1.34)	0.031
Q1	624 (3.74)	1.62 (1.40–1.89)	<0.001	1.29 (1.11–1.50)	0.001
Marital status
Married	1,552 (2.67)	Reference		Reference
Single	233 (2.16)	1.01 (0.88–1.16)	0.855	0.96 (0.83–1.10)	0.562
Divorced	442 (4.49)	1.71 (1.46–2.02)	<0.001	1.41 (1.27–1.58)	<0.001
Widowed	67 (5.17)	1.59 (1.20–2.11)	0.001	1.38 (1.07–1.77)	0.013
Country of birth
Sweden	1,947 (2.84)	Reference		Reference
Foreign born	347 (3.03)	0.99 (0.88–1.12)	0.964	0.93 (0.82–1.04)	0.183
Age group
<40	408 (1.59)	Reference		Reference
40–50	1,293 (3.02)	2.14 (1.91–2.39)	<0.001	1.53 (1.36–1.72)	<0.001
≥50	525 (5.06)	4.47 (3.82–5.24)	<0.001	2.71 (2.31–3.19)	<0.001
Sex
Women	733 (3.53)	Reference		Reference
Men	1,561 (2.64)	1.31 (1.15–1.49)	<0.001	1.50 (1.29–1.74)	<0.001
BMI
18.5–24.9	1,333 (2.8)	–	–	Reference
<18.5	126 (5.05)	–	–	1.45 (1.16–1.81)	<0.001
25–29.9	668 (2.63)	–	–	0.91 (0.83–1.01)	0.060
>30	167 (3.54)	–	–	1.06 (0.90–1.24)	0.238
FEV1	–	–	–	0.36 (0.34–0.38)	<0.001
Smoking status
Never smoker	227 (0.76)	–	–	Reference
Former smoker	218 (1.53)	–	–	1.61 (1.34–1.94)	<0.001
Current smoker	1,849 (5.12)	–	–	5.65 (4.91–6.50)	<0.001

^a Model 1 including age, sex, occupation, marital status, annual income and country of birth.

^b Model 2 including age, sex, occupation, marital status, annual income, country of birth, plus BMI, forced expiratory volume in 1 second and smoking status.

P-y: person-years; HR: hazard ratio; CI: confidence interval; FEV1: Forced Expiratory volume in 1 second.