Table A-2.

COPD: Correlations with Prevalent Comorbid Conditions

	COPD			Comorbid Condition
	Co1	Co2	Co3	CC1	CC2
COPD (N=274)
Co1 Shortness of breath^a
Co2 COPD severity	0.60
Co3 COPD QOL impact	0.62	0.84
Obesity (N=78)
Ob1 Body mass index	0.12	0.10	0.15
Ob2 Obesity severity	0.13	0.31	0.32	0.67
Ob3 Obesity QOL impact	0.25	0.38	0.45	0.68	0.82
Asthma (N=138)
As2 Asthma severity	0.44	0.67*	0.67*	---
As3 Asthma QOL impact	0.52*	0.72*	0.79*	---	0.86
Diabetes (N=59)
Di2 Diabetes severity	0.08	0.32	0.31	---
Di3 Diabetes QOL impact	0.25	0.45	0.50	---	0.76
Osteoarthritis (N=82)
OA2 OA severity	0.08	0.21	0.27	---
OA3 OA QOL impact	0.19	0.24	0.36	---	0.80
Allergies-chronic (N=126)
Allc2 Allergy-chronic severity	0.18	0.41	0.41	---
Allc3 Allergy-chronic QOL impact	0.20	0.41	0.52*	---	0.75
Allergies-seasonal (N=146)
Alls2 Allergy-seasonal severity	0.24	0.43	0.48	---
Alls3 Allergy-seasonal QOL impact	0.19	0.38	0.47	---	0.81
Chronic back problems (N=115)
Bp2 Back severity	0.38	0.45	0.46	---
Bp3 Back QOL impact	0.37	0.46	0.52*	---	0.86
Depression (N=66)
De2 Depression severity	0.32	0.58*	0.56*	---
De3 Depression QOL impact	0.27	0.55*	0.51	---	0.87
Hearing, trouble (N=81)
He2 Hearing severity	0.10	0.19	0.15	---
He3 Hearing QOL impact	0.13	0.22	0.28	---	0.52
Hypertension (N=168)
Hy2 Hypertension severity	0.16	0.39	0.35	---
Hy3 Hypertension QOL impact	0.30	0.51	0.51	---	0.59
Hypothyroidism (N=52)
Th2 Hypothyroidism severity	0.02	0.41	0.42	---
Th3 Hypothyroidism QOL impact	0.14	0.42	0.41	---	0.66
Joint problems, hip/knee (N=94)
Hk2 Hip/knee severity	0.25	0.25	0.26	---
Hk3 Hip/knee QOL impact	0.26	0.25	0.29	---	0.87
Osteoporosis (N=52)
Os2 Osteoporosis severity	0.06	0.22	0.17	---
Os3 Osteoporosis QOL impact	0.16	0.24	0.24	---	0.74
Vision, trouble (N=61)
Vi2 Vision severity	0.19	0.29	0.28	---
Vi3 Vision QOL impact	0.20	0.31	0.32	---	0.76

CC1 = Symptom measure for comorbid condition; CC2 = Severity measure for comorbid condition.

Higher scores on severity and impact items indicate greater disease severity or greater disease impact.

Shortness of breath defined in Table 1. Higher scores indicate greater shortness of breath.

Heterotrait correlations r>0.51 (absolute value) failed convergent-discriminant 1-tailed test. Median (r=0.62) correlation from convergent triangle selected for convergent-discriminant comparisons.