Table 1.

Prevalence of psychiatric disorders among COPD patients. Abbreviations: COPD, chronic obstructive pulmonary disease.

Reference	Study Type	Disease	Subjects (n)	Reported Prevalence
[12]	Case-control study	Generalized anxiety disorder	COPD = 74 Controls = 74	5.41% 1.35%
		Major depressive episode	COPD = 74 Controls = 74	2.70% 0
		Panic disorder	COPD = 74 Controls = 74	4.05% 0
		Substance dependence	COPD = 74 Controls = 74	16.21% 1.35%
[26]	Metanalysis	Depression	COPD = 5552 Controls = 5211	27.1% [25.9–28.3] * 10.0% [9.2–10.8] *
[25]	Review	Depression and anxiety	-	Depression: 10–42% Anxiety: 10–19%
[33]	Observational study	Depression	Chronic bronchitis = 1440 Emphysema = 518 Controls = 32,509	8.7% (6.8–10.7) § 7.5% (4.7–10.2) 3.6% (3.3–3.8)
		Bipolar disorder	Chronic bronchitis = 1440 Emphysema = 518 Controls = 32,509	3.3% (2.1–4.6) - 0.8% (0.7–0.9)
		Panic disorder	Chronic bronchitis = 1440 Emphysema = 518 Controls = 32,509	6.5% (4.6–8.3) - 1.8% (1.6–2.0)
		Social phobia	Chronic bronchitis = 1440 Emphysema = 518 Controls = 32,509	7.2% (5.3–9.1) 6.5% (3.7–9.2) 2.8% (2.5–3.0)
		Substance dependence	Chronic bronchitis = 1440 Emphysema = 518 Controls = 32,509	7.9% (5.0–10.8) - 2.8% (2.6–3.0)
[31]	Metanalysis	Generalized anxiety disorder	COPD inpatients = 358 COPD outpatients = 333	10–55% 13–46%

* Data expressed as mean and 95% confidence interval. ^§ Data expressed as relative percentage and 95% confidence interval.