Table 1.

Characteristics of Chinese individuals receiving methadone maintenance treatment (MMT) for heroin dependence and prevalence rates of attempted suicide by different characteristics.

Characteristics		n	One-month attempted suicide				Lifetime attempted suicide
			Number	%	χ2	P	Number	%	χ2	P
Gender	Male	412	35	8.5			127	30.8
	Female	191	22	11.5	1.259	0.262	79	41.4	8.475	0.004
Age (years)**	20–39	327	41	12.5			131	40.1
	40–59	276	16	5.8	7.495	0.006	75	27.2	10.737	0.001
Education	Primary school or lower	64	16	25.0			37	57.8
	Middle school or higher	539	41	7.6	18.255	<0.001	169	31.4	18.875	<0.001
Marital status	Married	295	25	8.5			94	31.9
	Non-married*	308	32	10.4	0.48	0.488	112	36.4	1.529	0.616
Employment status	Yes	317	20	6.3			100	31.5
	No	286	37	12.9	6.701	0.010	106	37.1	1.898	0.168
Self-rated economic status	Good	149	7	4.7			40	26.8
	Fair	314	27	8.6			99	31.5
	Poor	140	23	16.4	11.722	0.003	67	47.9	13.495	0.001
Route of past heroin administration	Smoking	96	1	1.0			11	11.5
	Injecting	507	56	11.0	9.16	0.002	196	38.7	21.701	<0.001
Duration of past heroin use (years)**	≤10	373	41	11.0			119	31.9
	>10	230	16	7.0	2.535	0.111	87	37.8	2.049	0.152
Duration of MMT (months)**	≤24	240	20	8.3			71	29.6
	>24	363	37	10.2	0.546	0.460	145	39.9	6.657	0.010
Methadone dose (md/d)**	≤70	273	30	10.9			110	40.3
	>70	330	27	8.2	1.797	0.180	96	29.1	7.428	0.006
Depressive symptoms	No	399	21	5.3			128	32.1
	Yes	204	36	17.6	22.586	<0.001	78	38.2	2.495	0.114
Anxiety symptom	No	384	20	5.2			105	27.3
	Yes	219	37	16.9	18.285	<0.001	101	46.1	18.853	<0.001
Pain	No	280	23	8.2			85	30.4
	Yes	323	34	10.5	0.749	0.387	121	37.5	3.286	0.070
Loneliness	No	226	11	4.9			79	35.0
	Yes	337	46	13.6	14.109	<0.001	126	37.4	0.328	0.567
Antisocial personality disorder	No	381	17	4.5			97	25.5
	Yes	222	40	18.0	29.212	<0.001	109	49.1	33.679	<0.001

*”Non-married” includes never-married, remarried, cohabitating, separated/divorced, and widowed.

**Continuous variables were dichotomized by a median split approach.