Asthma, Chronic Obstructive Pulmonary Disease, and Mortality in the U.S. Population

Figures & data

Table 1  Characteristics of analyzed population at baseline (n = 15,203) with deaths (n = 4,542) at up to 18 years of follow-up

	N	% (weighted)	Person-Years of Follow-up	Deaths per 1,000 Person Years (weighted)
Sex
Female	8,093	52.5	105,557	14.1
Male	7,110	47.5	89,247	14.8
Age Group, Years
25–44	6,577	51.8	96,975	2.4
45–54	1,990	15.9	28,372	8.5
55–64	2,147	13.3	28,283	19.0
65–74	2,260	11.6	25,233	45.6
75–84	1,669	5.9	12,839	103.3
85 +	560	1.5	3,104	172.7
Body Mass Index, kg/m^2
< 18.5	255	1.9	2,837	21.4
18.5–24	4,925	38.3	64,293	11.4
25–29	4,978	31.8	64,807	13.9
> = 30	3,701	22.1	49,434	14.6
Missing	1,344	6.0	13,434	39.5
Education, Years
< 12	6,645	26.6	80,772	25.4
12	4,178	30.6	54,782	14.2
> 12	4,380	42.8	59,250	8.4
Race/Ethnicity
White	6,691	77.4	80,683	15.3
Black	4,121	10.6	53,663	16.0
Mexican-American	3,804	4.9	52,652	8.4
Other	587	7.4	7,806	7.4
Smoking Status
Never	7,126	44.0	92,826	14.1
Former	3,987	26.6	47,832	19.9
Current	4,090	29.4	54,147	11.6
Respiratory Disease
COPD/Asthma	357	2.7	4,028	28.3
COPD only	815	5.3	8,735	36.1
Asthma only	709	5.3	9,187	11.7
None	13,322	86.7	172,854	13.1
Lung Function Status*
Obstructed	1,205	7.5	12,169	45.2
Restricted	1,635	7.7	19,717	25.1
Symptoms	3,727	26.4	48,717	13.5
No Testing	2,045	10.2	21,445	34.3
Normal	6,591	48.3	92,757	6.3

*Lung function status, as defined in methods.

Table 2  Characteristics of analyzed population at baseline (n = 15,203) by respiratory disease status

	COPD/Asthma	COPD Only	Asthma Only	None
	n = 357	n = 815	n = 709	n = 13,322
	% (weighted)	% (weighted)	% (weighted)	% (weighted)
Sex
Female	62.0	61.3	50.6	51.7
Mean Age (Standard Error)	50.9 (1.1)	56.0 (0.8)	44.9 (0.8)	47.0 (0.4)
Body Mass Index, kg/m^2
< 18.5	2.5	4.1	2.6	1.7
18.5–24	33.1	37.6	34.7	36.7
25–29	24.5	25.6	31.2	32.5
> = 30	32.4	23.0	24.6	21.5
Missing	7.5	9.7	6.9	5.7
Education, Years
<12	35.4	38.2	25.7	25.7
12	32.3	34.6	27.7	30.5
>12	32.3	27.2	46.6	43.8
Race/Ethnicity
White	78.6	88.2	79.1	76.6
Black	9.5	7.0	10.9	10.9
Mexican-American	2.2	2.2	3.3	4.9
Other	9.7	2.7	6.8	7.6
Smoking Status
Never	41.0	40.9	31.6	28.2
Former	31.4	35.8	25.5	26.0
Current	27.6	23.2	42.9	45.8
Lung Function Status*
Obstructed	30.9	24.3	13.3	5.4
Restricted	8.5	8.2	7.5	7.7
Symptoms	44.0	38.0	46.4	23.9
No Testing	8.2	12.3	10.7	10.1
Normal	8.4	17.3	22.0	53.0

*Lung function status, as defined in methods.

Table 3  Results from logistic regression model predicting the presence of Stage 2 obstruction (FEV₁/FVC < 70% and FEV₁< 80% predicted) in 13,871 subjects

	Odds Ratio (95% Confidence Interval)
Sex
Male	1.29 (1.04, 1.61)
Female	1
Age	1.06 (1.05, 1.07)
Body Mass Index, kg/m^2
<18.5	2.62 (1.59, 4.29)
18.5–24	1
25–29	0.78 (0.62, 1.00)
>= 30	0.95 (0.75, 1.20)
Education, Years
<12	1.41 (1.13, 1.78)
12	1.46 (1.15, 1.86)
>12	1
Race/Ethnicity
White	1
Black	0.76 (0.60, 0.96)
Mexican-American	0.58 (0.43, 0.77)
Other	1.16 (0.65, 2.08)
Smoking Status
Never	1
Former	2.03 (1.60, 2.58)
Current	4.30 (3.24, 5.71)
Respiratory Disease
COPD/Asthma	7.64 (5.08, 11.49)
COPD only	3.50 (2.52, 4.85)
Asthma only	3.70 (2.67, 5.13)
None	1.00 (1.00, 1.00)

Figure 1  Results from adjusted logistic regression model predicting the presence of Stage 2 obstruction (FEV₁/FVC < 70% and FEV₁< 80% predicted), demonstrating the interaction between smoking status and reported lifetime history of asthma, COPD, or both.

Figure 2  Results from Cox proportion hazard models. Curves are adjusted for sex, age, body mass index, education, race/ethnicity, and smoking status at baseline.

Table 4  Results from Cox Proportional hazards survival models on baseline sample- mortality follow-up of up to 18 years.

	Hazards Ratio (95% Confidence Interval)	Hazards Ratio (95% Confidence Interval)
Sex	A	B
Male	1.35 (1.23, 1.49)	1.35 (1.23, 1.48)
Female	1	1
Age	1.10 (1.09, 1.11)	1.10 (1.09, 1.10)
Body Mass Index, kg/m^2
<18.5	1.96 (1.46, 2.63)	1.71 (1.24, 2.36)
18.5–24	1	1
25–29	0.93 (0.83, 1.04)	0.92 (0.81, 1.03)
> = 30	1.11 (0.99, 1.24)	1.04 (0.92, 1.17)
Missing	1.57 (1.37, 1.80)	1.74 (1.39, 2.19)
Education, Years
<12	1.36 (1.18, 1.57)	1.31 (1.14, 1.50)
12	1.42 (1.25, 1.60)	1.37 (1.22, 1.55)
>12	1	1
Race/Ethnicity
White	1	1
Black	1.32 (1.19, 1.47)	1.34 (1.20, 1.49)
Mexican-American	1.01 (0.87, 1.18)	0.94 (0.81, 1.10)
Other	0.71 (0.59, 0.87)	0.68 (0.56, 0.82)
Smoking Status
Never	1	1
Former	1.28 (1.14, 1.44)	1.22 (1.09, 1.37)
Current	2.06 (1.83, 2.31)	1.82 (1.62, 2.04)
Respiratory Disease
COPD/Asthma	1.83 (1.34, 2.49)	1.45 (1.06, 1.98)
COPD only	1.44 (1.28, 1.62)	1.28 (1.13, 1.45)
Asthma only	1.16 (0.94, 1.42)	1.04 (0.85, 1.27)
None	1	1
Lung Function Status *
Obstructed		2.07 (1.80, 2.37)
Restricted		1.95 (1.69, 2.25)
Symptoms		1.32 (1.18, 1.49)
No Testing		1.25 (1.01, 1.55)
Normal		1

*Lung function status, as defined in methods.

Model A adjusts for all factors except Disease Stage and Model B adjusts for all factors.

Figure 3  Results from Cox proportion hazard models. Curves are adjusted for sex, age, body mass index, education, race/ethnicity, smoking status and lung function status at baseline.