Perceived advantages and disadvantages of substance use in a dual diagnosis population with severe mental disorders and severe substance use disorder. Considering the self-medication hypothesis

Figures & data

Figure 1. Comparison DUDIT-E and DrugCheck items on domains affected and type of problems.

Table 1. Demographics and descriptive features of the population by DUDIT-E or DrugCheck questionnaire respectively.

		Total	Questionnaire filled in
			None		DrugCheck		DUDIT-E
		N	N	%	N	%	N	%
Total		1076	339		607		130
Main diagnostic group	F2 Schizophrenia, schizotypal and delusional disorders	432	150	44.2	223	36.7	59	45.4
	F3 Mood [affective] disorders	228	65	19.2	138	22.7	25	19.2
	F4 Neurotic, stress-related and somatoform disorders	115	36	10.6	73	12.0	6	4.6
	F6 Disorders of adult personality and behaviour	134	36	10.6	74	12.2	24	18.5
	Other diagnosis	167	52	15.3	99	16.3	16	12.3
Gender	Male	726	236	69.6	403	66.4	87	66.9
	Female	350	103	30.4	204	33.6	43	33.1
Age group	18–29 years	328	106	31.3	177	29.2	45	34.6
	30–39 years	305	90	26.5	185	30.5	30	23.1
	40–49 years	282	90	26.5	159	26.2	33	25.4
	50 Years or above	161	53	15.6	86	14.2	22	16.9
Year of admission	2010–2011	323	140	41.3	183	30.1	.
	2012–2013	294	81	23.9	213	35.1	.
	2014–2015	258	59	17.4	198	32.6
	2016–2017	201	59	17.4	13	2.1	129	99.2
Length of stay	<30 days	235	146	43.1	74	12.2	15	11.5
	30–90 days	296	85	25.1	167	27.5	44	33.8
	90 + days	545	108	31.9	366	60.3	71	54.6
Substances used on a weekly basis according to DrugCheck or DUDIT-E	Alcohol	276	.		217	35.7	59	45.4
	Opiates	81	.		70	11.5	11	8.5
	Cannabis	207	.		150	24.7	57	43.8
	Cocaine	85	.		68	11.2	17	13.1
	Hallucinogenes	3	.		3	0.5	.
	Solvents	6	.		5	0.8
	Sleeping/tranquilizers	214	.		177	29.2	37	28.5
	Pain	86	.		70	11.5	16	12.3
Substance-related diagnosis	Alcohol	548	157	46.3	325	53.5	66	50.8
	Opiates	216	63	18.6	140	23.1	13	10.0
	Cannabis	526	157	46.3	304	50.1	65	50.0
	Hypnotics	193	55	16.2	125	20.6	13	10.0
	Cocaine	195	44	13.0	118	19.4	33	25.4
	Other stimulants	158	53	15.6	89	14.7	16	12.3
	Hallucinogenics	18	9	2.7	9	1.5	.
	Solvents	4	–	–	–	–	–	–
	Multiple	79	26	7.7	43	7.1	10	7.7

Table 2. Ranking of problems listed on the DrugCheck questionnaire according to percentage answering ‘some’ or ‘a lot’.

N = range 566–585 depending on question (not all questions answered in all cases) ‘Have you, within the last three months….’	Some or a lot (%)
Felt depressed?	64.3
Did (substance) cause any money problems for you?	55.1
Been uninterested in your usual activities?	54.5
Were there problems at home or with your family because of (substance)?	53.9
Had strange thoughts?	53.2
Been suspicious or distrustful of others?	47.6
Did (substance) make you have problems at work, or at school (College/University/training courses)?	41.7
Has (substance) caused any health problems or injuries?	38.0
Did you have any arguments or fights because of (substance)?	29.9
Did you have housing problems because of (substance)?	28.0
Forgotten to take your medication?*	25.9
Have you done anything ‘risky’ or ‘outrageous’ after using (substance) (e.g. driving under the influence; unprotected sex; sharing needles)?	23.1
Has (substance) caused any trouble with the law, or the police?	18.1

*Add-on question specifying for dual diagnosis patients.

Table 3. Ranking of experienced negative consequences reported on the DUDIT-E questionnaire (two different scales) according to most often experienced to the least often experienced.

Question (n = 125–128 depending on question) What is negative for you	Every week or daily or almost daily (%)	Very/absolutely
In the past year, I’ve had trouble at work due to use of substances	50.8
In the past year, I’ve been to the doctor or hospital due to use of substances	14.8
In the past year, I’ve argued or been violent due to use of substances	9.0
In the past year, I’ve had problems with the police due to use of substances	1.6
Do you experience ruined financial situation?		67.8
Do you experience decreased health?		52.5
Do you experience destruction of family life?		50.0
Do you experience passiveness?		49.2
Do you experience difficulty with concentration?		45.8
Do you experience avoiding social contact?		44.9
Do you experience less contact with friends?		44.9
Do you experience that everything is chaotic?		40.7
Do you experience anxiety?		32.2
Do you experience being inconsiderate?		27.1
Do you experience decreased sexual interest?		22.9
Do you experience suicidal thoughts?		17.8
Do you experience headache, nausea, or vomiting?		14.4

Table 4. Ranking of positive effects of using preferred substance reported on the DUDIT-E questionnaire.

Positive effects of using preferred substance (n = 126–129 depending on question)	Very/absolutely (%)
Relaxation	67.5
Improved sleep	48.8
Control of negative emotions (anger depression)	43.9
Feeling happy	37.4
On the substance I function better socially	31.7
Feeling normal	30.9
Decreased pain	30.1
Life without substance is dull	27.6
Increased creativity	26.0
Increased activity (e.g cleaning, work)	26.0
Increased self-confidence	26.0
Getting a sensation everything will be alright	24.4
Feeling strong	23.6
Better contact with others	20.3
On substance I feel part of group	17.1
I love everybody in the world	14.6
I get more out of life	11.4

Figure 2. Average number of problems listed on the Drugcheck questionnaire according to primary diagnosis and substances used weekly. *T-test against the remainder. **Test of trend.