Table 3.

Demographic and clinical correlates independently associated with smoking by diagnoses.

	Schizophrenia			Bipolar disorder			Major depressive disorders
	P value	OR	95% C.I.	P value	OR	95% C.I.	P value	OR	95% C.I.
Male gender	<0.001	31.0	12.0–80.2	<0.001	16.3	7.9–33.3	<0.001	32.2	6.0–171.7
Married/cohabitating	0.31	1.5	0.6–3.3	0.93	0.9	0.4–2.1	0.18	3.2	0.5–18.3
First episode	0.12	1.7	0.8–3.6	0.01	0.3	0.1–0.7	0.11	0.2	0.03–1.4
Living alone	0.06	2.6	0.9–7.4	0.001	5.4	1.9–15.1	0.99	<0.001	—
Personal income (>3000 RMB)	0.40	1.4	0.6–3.3	0.03	2.2	1.07–4.7	0.42	1.7	0.4–7.4
Health insurance	0.90	1.0	0.5–2.0	<0.001	4.8	2.2–10.7	0.24	2.5	0.5–12.7
Major medical conditions	0.96	0.9	0.4–2.3	0.10	0.4	0.1–1.1	0.32	2.4	0.4–14.0
Family history of psychiatric disorders	0.74	1.1	0.5–2.1	0.97	0.9	0.4–1.9	0.93	0.9	0.2–4.0
Education (years)	0.31	0.9	0.8–1.0	0.01	0.8	0.7–0.9	0.7	0.9	0.7–1.1
Age of onset (years)	0.01	1.04	1.008–1.08	0.21	1.0	0.9–1.0	0.03	0.9	0.8–1.0
Length of illness (years)	0.89	1.0	0.9–1.04	0.90	1.0	0.9–1.0	0.14	0.9	0.9–1.0
Number of admissions	0.06	1.1	0.9–1.2	0.45	1.0	0.9–1.2	0.49	0.7	0.4–1.5
SCL-90 total	0.27	1.0	0.9–1.0	0.82	1.0	0.9–1.0	0.5	1.003	0.9–1.0

Bolded values: <0.05; SCL-90 = Symptom Checklist-90; SF-12 = Medical Outcomes Study Short Form; OR = Odds ratio; Due to collinearity between age and age of onset in schizophrenia, between age and age of onset and length of illness in bipolar disorder and between age and age of onset and length of illness in major depressive disorders, age was not entered as independent variable in the above multiple logistic regression analyses.