Testing the hypothesis of subtypes of nonadherence in schizophrenia and schizoaffective disorder: A prospective study

Table 1 Sociodemographic, clinical, and treatment-related characteristics of the sample at admission and differences between unintentional and intentional nonadherent patients

	Total non-adherence (n = 64)	Unintentional (n = 32)	Intentional (n = 32)	P value
Age (yr)	40.6 ± 9.6	44.4 ± 10.1	36.8 ± 7.4	0.001
Sex (male)	39 (60.9)	23 (71.9)	16 (50.0)	0.073
Marital status				0.522
Married or stable relationship	12 (18.8)	5 (15.6)	7 (21.9)
Single, separated, divorced, or widowed	52 (81.2)	27 (84.4)	25 (78.1)
Educational level				< 0.001
Primary or lower	34 (53.1)	25 (78.1)	9 (28.1)
Secondary or higher	30 (46.9)	7 (21.9)	23 (71.9)
Socio-economic level				0.376
Low	49 (76.6)	26 (81.2)	23 (71.9)
Medium-High	15 (23.4)	6 (18.8)	9 (28.1)
Employment situation				0.162
Active	5 (7.8)	1 (3.1)	4 (12.5)
No active	59 (92.2)	31 (96.9)	28 (87.5)
Cohabitation				0.794
Living with family	41 (64.1)	20 (62.5)	21 (65.6)
Living alone	23 (35.9)	12 (37.5)	11 (34.4)
Length of admission (d)	23 (14-32)	25 (14-35)	21 (14-26)	0.179
Length of the disorder (yr)	11 (5-19)	11 (5-20)	10 (6-17)	0.577
Number of previous psychiatric admissions	2.0 (1.0-5.0)	1.0 (1.0-4.0)	3.0 (1.0-5.2)	0.036
Time since last hospitalization (yr)	2.0 (1.1-5.0)	2.0 (1.0-7.3)	2.0 (1.3-3.0)	0.435
ICD diagnosis				0.079
Schizophrenia	35 (54.7)	21 (65.6)	14 (43.8)
Schizoaffective disorder	29 (45.3)	11 (34.4)	18 (56.2)
Current substance use or abuse	36 (56.2)	18 (56.2)	18 (56.2)	1
History of substance use or abuse	44 (68.8)	22 (68.8)	22 (68.8)	1
Daily doses (oral antipsychotic)	1.0 (1.0-2.0)	1.0 (1.0-2.0)	1.0 (1.0-2.0)	0.243
Psychotropic pills per day	6 (4-8)	6 (4-8)	5 (3-9)	0.479
Attitude towards treatment				0.664
Negative	41 (64.1)	19 (59.4)	22 (68.8)
Neutral	15 (23.4)	9 (28.1)	6 (18.8)
Positive	8 (12.5)	4 (12.5)	4 (12.5)

Data are means ± SD, frequencies (%) and medians (IQR).

Table 2 Psychopathological, treatment-related, and other characteristics of nonadherent patients during hospitalization and at 6 mo post discharge, and differences between unintentional and intentional nonadherence

	Hospitalization				6 mo
	Total Nonadherence (n = 64)	Unintentional (n = 32)	Intentional (n = 32)	P value	Total nonadherence (n = 64)	Unintentional (n = 32)	Intentional (n = 32)	P value
Amador insight scale, general disorder awareness	11 (9-15)	11 (9-15)	11 (9-15)	0.634	9 (9-11)	9 (6-11)	9 (9-13)	0.467
Mental disorder	5 (3-5)	5 (3-5)	5 (3-5)	0.750	3.0 (3.0-5.0)	3.0 (2.0-4.5)	3.0 (3.0-5.0)	0.177
Effects of the medication	3.0 (3.0-5.0)	3.0 (3.0-5.0)	3.0 (3.0-5.0)	0.638	3.0 (2.0-3.0)	3.0 (2.2-3.0)	3.0 (2.5-4.0)	0.907
Social consequences	3.0 (3.0-5.0)	3.0 (3.0-5.0)	4.0 (3.0- 5.0)	0.441	3.0 (2.0-5.0)	3.0 (2.2-4.8)	3.0 (2.5-5.0)	0.861
CGI-SCH severity. Total score	11 (10-13)	11 (10-13)	10 (9-12)	0.086	10 (9-12)	12 (10-13)	9 (8-10)	0.003
Psychotic symptoms	3.0 (3.0-3.0)	3.0 (3.0-3.0)	3.0 (3.0- 3.0)	0.645	2.0 (2.0- 3.0)	3.0 (2.0-3.0)	2.0 (2.0-3.0)	0.118
Negative symptoms	2.0 (1.0-2.2)	2.0 (1.0-2.2)	2.0 (1.0-2.2)	0.186	2.0 (1.0-2.0)	2.0 (2.0-3.0)	2.0 (1.0-2.0)	< 0.001
Depressive symptoms	1.0 (1.0-2.0)	1.0 (1.0-2.0)	1.0 (1.0-2.0)	0.413	1.0 (1.0-2.0)	1.0 (1.0-2.0)	1.0 (1.0-2.0)	0.346
Cognitive symptoms	2.0 (1.0-2.0)	2.0 (2.0-2.0)	1.0 (1.0-2.0)	< 0.001	2.0 (1.0-2.0)	2.0 (2.0-2.8)	1.0 (1.0-2.0)	< 0.001
Global severity	3.0 (3.0-3.0)	3.0 (3.0- 3.0)	3.0 (2.8-3.0)	0.679	3.0 (2.0-3.0)	3.0 (2.0-3.0)	2.0 (2.0-3.0)	0.210
SCIP. Total score	49 (40-55)	42 (32-52)	52 (46-59)	0.002	48 (41-59)	42 (33-49)	56 (48-62)	< 0.001
Verbal learning-immediate	13 (10-15)	12 (9-15)	13 (11-15)	0.073	15 (11-17)	13 (10-16)	15 (12-18)	0.032
Working memory	16 (13-20)	14 (11-18)	18 (16-21)	0.004	17 (14-20)	14 (12-17)	19 (17-20)	0.001
Verbal fluency	10 (8-13)	10 (7-11)	12 (9-14)	0.022	11 (8-12)	10 (7-11)	11 (8-13)	0.045
Verbal learning-delayed	4.0 (2.0-5.0)	3.0 (2.0-4.0)	4.0 (3.0-5.0)	0.003	4.0 (3.0-5.0)	3.0 (1.2-4.0)	5.0 (4.0-6.0)	< 0.001
Processing speed	4.0 (3.0-6.0)	3.0 (2.0-5.0)	5.0 (3.0-7.0)	0.004	4.0 (3.0-5.0)	3.0 (2.0-4.0)	5.0 (4.0-6.0)	< 0.001
Type of antipsychotic treatment				0.114				0.114
Oral	22 (34.4)	8 (25.0)	14 (43.8)		22 (34.4)	8 (25.0)	14 (43.8)
Injectable or injectable + oral	42 (65.6)	24 (75)	18 (56.2)		42 (65.6)	24 (75)	18 (56.2)
Supervision of the treatment	40 (65.6)	21 (67.7)	19 (63.3)	0.717	51 (79.7)	29 (90.6)	22 (68.8)	0.03
SDM-Q-9. total score	17 (9-23)	10 (8-19)	20 (11-30)	0.010	18 (11-21)	17 (10-21)	18 (14-22)	0.235
BMQ, beliefs about medicines, general	22 (18-27)	22 (20-27)	22 (17-25)	0.509	22 (18-26)	22 (18-26)	22 (16-25)	0.623
BMQ, beliefs about medicines, specific	6 (5-7)	6 (6-7)	6 (5-7)	0.142	31 (26-34)	31 (27-35)	30 (26-34)	0.479
DAI	3.0 (-3.0-7.0)	3.0 (-1.0-5.0)	1.0 (-3.0-7.0)	0.914	1.0 (-3.0-3.0)	1.0 (-3.0-6.5)	1.0 (-3.0-3.0)	0.374
Morisky-Green test	2.0 (2.0-3.0)	2.0 (1.8-2.2)	2.0 (2.0-3.0)	0.302	2.0 (2.0-3.0)	2.0 (2.0-3.0)	2.5 (2.0-3.0)	0.084
BARS	100 (100-100)	100 (100-100)	100 (100-100)	0.329	55 (30-74)	60 (20-78)	50 (40-70)	0.586
Knowledge of the treatment at 1 h1	75 (58-92)	67 (58-75)	83 (75-92)	< .001
Knowledge of the treatment at 20 d1	79 (62-92)	65 (42-77)	83 (81-92)	< .001
Knowledge of the treatment at 6 mo1					80 (60-90)	60 (40-70)	90 (80-100)	< 0.001

Data are means ± SD, frequencies (%) and medians (IQR).

¹There were 3 lost cases regarding knowledge of the treatment (n = 61; unintentional, n = 30; intentional, n = 31). Knowledge of the treatment: Knowledge of the treatment, diagnosis, and follow-up from the time of instruction. The values represent means of percentages. BMQ: Beliefs about medicines questionnaire; CGI-SCH: Clinical Global Impression–Schizophrenia; IQR: Inter-quartile range; SCIP: Screen for Cognitive Impairment in Psychiatry; SDM-Q-9: Shared Decision Making Questionnaire; SD: Standard deviation; DAI: Drug attitude inventory; BARS: Brief adherence rating scale.

Table 3 Variables associated with nonadherence according to intentionality after multivariate logistic regression (reference: Unintentional nonadherence)

	P value1	AIC2	Odds ratio (95%CI)
Low educational level	< 0.001	52.1	26.1 (2.819; 241)
Non-psychiatric treatment at 6 mo	0.003	47.7	15.8 (1.790; 139)
Treatment knowledge at 6 mo, mean	< 0.001	64.9	0.904 (0.853; 0.957)

¹Likelihood ratio test.

²If the variable is removed. AIC for the full model = 41.1; AIC is a measure of lack of fit. The removal of any variable leads to a model with more lack of fit. AIC: Akaike information criterion.