Health-related quality of life in current smokers with COPD: factors associated with current smoking and new insights into sex differences

Figures & data

Table 1 Characteristics of adults with COPD and their smoking status (n=10,963)

Characteristics	Unweighted n	Overall mean or proportion (95% CI)	Smoking status
			Current (n=4,576) mean or proportion (95% CI)	Former (n=6,387) mean or proportion (95% CI)
Sociodemographics
Age	10,963	58.5 (57.8–59.2)	52.4 (51.5–53.3)	64.3 (63.3–65.3)
Sex
Male	4,154	46.7 (44.7–48.6)	45.7 (42.8–48.7)	47.6 (45.0–50.1)
Female	6,809	53.3 (51.4–55.3)	54.3 (51.3–57.2)	52.4 (49.9–55.0)
Ethnicity
White non-Hispanic	9,264	80.1 (78.3–81.9)	78.4 (75.7–81.0)	81.7 (79.3–84.2)
Black non-Hispanic	767	8.7 (7.4–10.0)	10.7 (8.6–12.9)	6.8 (5.4–8.2)
Hispanic	278	4.5 (3.5–5.5)	4.4 (3.1–5.7)	4.7 (3.3–6.1)
Othersa	654	6.7 (5.5–7.9)	6.5 (5.1–8.0)	6.8 (4.9–8.7)
Marital status
Married	4,530	47.2 (45.3–49.2)	41.7 (38.9–44.6)	52.5 (50.0–55.0)
Unmarriedb	6,433	52.8 (50.8–54.7)	58.3 (55.4–61.1)	47.5 (45.0–50.0)
Education
Elementary/high school/some college	9,105	89.4 (88.4–90.3)	93.1 (91.9–94.2)	85.8 (84.4–87.2)
College graduate	1,858	10.6 (9.7–11.6)	6.9 (5.8–8.1)	14.2 (12.8–15.6)
Employment
Employed	2,033	24.2 (22.4–26.1)	28.5 (25.7–31.2)	20.2 (17.6–22.8)
Unemployedc	8,930	75.8 (73.9–77.6)	71.5 (68.8–74.3)	79.8 (77.2–82.4)
Exercise
Yes	5,928	57.0 (55.1–58.8)	57.3 (54.5–60.0)	56.7 (54.3–59.1)
No	5,035	43.0 (41.2–44.9)	42.7 (40.0–45.5)	43.3 (40.9–45.7)
Binge drinking
Yes	909	11.4 (10.1–12.6)	15.5 (13.4–17.7)	7.4 (6.3–8.6)
No	10,054	88.6 (87.4–89.9)	84.5 (82.3–86.6)	92.6 (91.4–93.7)
Number of chronic conditions
0	2,875	27.8 (25.9–29.6)	29.8 (27.2–32.3)	25.9 (23.3–28.5)
1	3,932	36.1 (34.3–38.0)	37.0 (34.3–39.8)	35.3 (33.0–37.6)
≥2	4,156	36.1 (34.3–37.9)	33.2 (30.5–36)	38.8 (36.4–41.3)
Having a health plan
Yes	10,054	88.0 (86.5–89.4)	81.4 (78.8–83.9)	94.3 (93.1–95.5)
No	909	12.0 (10.6–13.5)	18.6 (16.1–21.2)	5.7 (4.5–6.9)
Having a primary care provider
Yes	10,294	90.3 (88.7–91.8)	85.0 (82.4–87.5)	95.4 (93.6–97.1)
No	669	9.7 (8.2–11.3)	15.0 (12.5–17.6)	4.6 (2.9–6.4)
Did not see a doctor in the past 12 months due to medical cost
Yes	2,007	24.1 (22.3–25.9)	32.7 (29.8–35.6)	15.9 (13.9–17.9)
No	8,956	75.9 (74.1–77.7)	67.3 (64.5–70.2)	84.1 (82.1–86.1)
Annual checkup
Yes	9,073	78.5 (76.6–80.3)	72.2 (69.4–75.0)	84.5 (82.3–86.7)
No	1,890	21.5 (19.7–23.4)	27.8 (25.0–30.6)	15.5 (13.3–17.7)
Shortness of breath affects quality of life
Yes	7,734	70.4 (68.6–72.2)	71.0 (68.3–73.6)	69.9 (67.6–72.1)
No	3,229	29.6 (27.8–31.4)	29.0 (26.4–31.7)	30.1 (27.9–32.4)
Seen a doctor in the past 12 months for symptoms related shortness of breath, bronchitis, or other COPD, or emphysema flare
Yes	5,248	47.2 (45.3–49.2)	44.3 (41.4–47.1)	50.1 (47.5–52.6)
No	5,715	52.8 (50.8–54.7)	55.7 (52.8–58.6)	49.9 (47.4–52.5)
Visited an emergency room or was admitted to the hospital in the past 12 months because of COPD, chronic bronchitis, or emphysema
Yes	1,937	18.6 (17.1–20.2)	19.2 (16.7–21.6)	18.1 (16.2–20.1)
No	9,026	81.4 (79.8–82.9)	80.8 (78.4–83.3)	81.9 (79.9–83.8)
Takes medications each day to help with COPD
Yes	7,648	66.9 (65.0–68.8)	63.4 (60.6–66.2)	70.2 (67.7–72.8)
No	3,315	33.1 (31.2–35.0)	36.6 (33.7–39.4)	29.8 (27.2–32.3)
Health-related quality of life
General health
Excellent/very good/good	4,668	43.1 (41.1–45.0)	40.4 (37.5–43.3)	45.7 (43.1–48.3)
Fair/poor	6,295	56.9 (55.0–58.9)	59.6 (56.7–62.5)	54.3 (51.7–56.9)
Frequent days of poor physical health
0–13 days	6,185	55.0 (53.1–57.0)	51.7 (48.8–54.6)	58.2 (55.8–60.7)
14–30 days	4,778	45.0 (43.0–46.9)	48.3 (45.4–51.2)	41.8 (39.3–44.2)
Frequent days of poor mental health
0–13 days	8,156	69.0 (67.1–70.8)	58.6 (55.8–61.4)	78.9 (76.7–81.1)
14–30 days	2,807	31.0 (29.2–32.9)	41.4 (38.6–44.2)	21.1 (18.9–23.3)
Frequent days of poor activity limitations
0–13 days	7,572	67.1 (65.3–68.9)	61.3 (58.5–64.1)	72.6 (70.5–74.8)
14–30 days	3,391	32.9 (31.1–34.7)	38.7 (35.9–41.5)	27.4 (25.2–29.5)

Notes:

a Others includes Asian non-Hispanic, American Indian/Alaskan Native non-Hispanic, and other race non-Hispanic.

b Unmarried includes divorced/widowed/separated/never married/member of an unmarried couple.

c Unemployed includes out of work, homemaker or student, retired, unable to work.

Abbreviation: CI, confidence interval.

Table 2 Estimated prevalence odds ratios and 95% CI for health-related quality of life: general health and physical health

Smoking status	“Fair/poor” general health		14–30 days of poor physical health
	UOR (95% CI)	AOR (95% CI)	UOR (95% CI)	AOR (95% CI)
All (n=10,963)
Current	1.2 (1.1–1.5)	1.2 (1.0–1.5)	1.3 (1.1–1.5)	1.3 (1.0–1.5)
Former	Reference	Reference	Reference	Reference
Males (n=4,154)
Current	1.2 (1.0–1.6)	1.5 (1.1–2.0)	1.2 (0.9–1.6)	1.2 (0.9–1.6)
Former	Reference	Reference	Reference	Reference
Females (n=6,809)
Current	1.2 (1.0–1.5)	1.1 (0.9–1.4)	1.4 (1.1–1.7)	1.3 (1.0–1.6)
Former	Reference	Reference	Reference	Reference

Notes: Adjusted for age, sex, ethnicity, marital status, education, employment, chronic conditions, physical activity, binge drinking, health care access and utilization, and COPD-related factors. AOR for males and females was adjusted for all covariates except sex. Significance (P=0.5) is shown in bold.

Abbreviations: AOR, adjusted odds ratio; CI, confidence interval; UOR, unadjusted odds ratio.

Table 3 Estimated prevalence odds ratios and 95% CI for health-related quality of life: mental health and activity limitations

Smoking status	14–30 days of poor mental health		14–30 days of poor activity limitations
	UOR (95% CI)	AOR (95% CI)	UOR (95% CI)	AOR (95% CI)
All (n=10,963)
Current	2.6 (2.2–3.2)	1.8 (1.4–2.2)	1.7 (1.4–2.0)	1.5 (1.3–1.9)
Former	Reference	Reference	Reference	Reference
Males (n=4,154)
Current	2.3 (1.6–3.1)	1.3 (0.9–2.0)	1.7 (1.3–2.2)	1.6 (1.2–2.2)
Former	Reference	Reference	Reference	Reference
Females (n=6,809)
Current	3.0 (2.4–3.6)	2.1 (1.7–2.6)	1.7 (1.4–2.0)	1.5 (1.2–1.9)
Former	Reference	Reference	Reference	Reference

Notes: Adjusted for age, sex, ethnicity, marital status, education, employment, chronic conditions, physical activity, binge drinking, health care access and utilization, and COPD-related factors. AOR for males and females was adjusted for all covariates except sex. Significance (P=0.5) is shown in bold.

Abbreviations: AOR, adjusted odds ratio; CI, confidence interval; UOR, unadjusted odds ratio.

Table 4 Estimated prevalence OR and 95% CI for current smoking (n=10,963)

Characteristics	Overall OR (95% CI)	Males OR (95% CI)	Females OR (95% CI)
Sociodemographics
Age (in years)	0.9 (0.9–1.0)	0.9 (0.9–0.96)	0.9 (0.9–1.0)
Sex
Female	Reference
Male	1.0 (0.8–1.2)	–	–
Ethnicity
White non-Hispanic	Reference	Reference	Reference
Black non-Hispanic	1.2 (0.8–1.8)	1.7 (0.9–3.4)	0.9 (0.6–1.3)
Hispanic	0.6 (0.4–1.1)	0.5 (0.2–1.1)	0.7 (0.4–1.4)
Othersa	0.8 (0.5–1.3)	0.9 (0.5–1.9)	0.8 (0.4–1.3)
Marital status
Married	Reference	Reference	Reference
Unmarriedb	1.5 (1.2–1.8)	1.5 (1.1–2.1)	1.4 (1.1–1.7)
Education
College graduate	Reference	Reference	Reference
Elementary/high school/some college	2.0 (1.5–2.5)	1.7 (1.3–2.4)	2.1 (1.5–3.0)
Employment
Employed	Reference	Reference	Reference
Unemployedc	1.1 (0.9–1.5)	1.6 (1.1–2.4)	0.9 (0.7–1.2)
Exercise
Yes	Reference	Reference	Reference
No	1.2 (1.0–1.4)	1.1 (0.8–1.5)	1.2 (1.0–1.5)
Binge drinking
No	Reference	Reference	Reference
Yes	1.5 (1.1–2.0)	1.8 (1.2–2.9)	1.1 (0.8–1.6)
Number of chronic conditions
0	Reference	Reference	Reference
1	1.0 (0.8–1.4)	1.1 (0.7–1.7)	1.0 (0.7–1.3)
≥2	1.1 (0.8–1.4)	1.1 (0.7–1.7)	1.0 (0.7–1.3)
Having a health plan
Yes	Reference	Reference	Reference
No	1.6 (1.1–2.3)	2.8 (1.5–5.0)	1.1 (0.8–1.7)
Having a primary care provider
Yes	Reference	Reference	Reference
No	1.1 (0.7–1.9)	1.1 (0.5–2.5)	1.1 (0.7–1.8)
Did not see a doctor in the past 12 months due to medical cost
Yes	Reference	Reference	Reference
No	0.0 (0.6–1.1)	0.9 (0.5–1.3)	0.8 (0.6–1.0)
Annual checkup
Yes	Reference	Reference	Reference
No	1.1 (0.9–1.5)	1.0 (0.7–1.6)	1.2 (0.9–1.6)
Shortness of breath affects quality of life
No	Reference	Reference	Reference
Yes	0.9 (0.7–1.2)	0.8 (0.6–1.2)	1.0 (0.8–1.2)
Seen a doctor in the past 12 months for symptoms related shortness of breath, bronchitis, or other COPD, or emphysema flare
Yes	Reference	Reference	Reference
No	1.4 (1.1–1.7)	1.2 (0.8–1.7)	1.6 (1.3–2.0)
Visited an emergency room or was admitted to the hospital in the past 12 months because of COPD, chronic bronchitis, or emphysema
Yes	Reference	Reference	Reference
No	1.1 (0.8–1.4)	1.3 (0.8–2.0)	0.9 (0.7–1.2)
Takes medications each day to help with COPD
Yes	Reference	Reference	Reference
No	1.0 (0.8–1.2)	1.0 (0.7–1.4)	0.9 (0.7–1.2)

Notes:

a Others includes Asian non-Hispanic, American Indian/Alaskan Native non-Hispanic, and Other race non-Hispanic.

b Unmarried includes divorced/widowed/separated/never married/member of an unmarried couple.

c Unemployed includes out of work, homemaker or student, retired, unable to work. Significance (P=0.5) is shown in bold.

Abbreviations: CI, confidence interval; OR, odds ratio.