To what extent is treatment adherence of psychiatric patients influenced by their participation in shared decision making?

Figures & data

Table 1 Sociodemographic and clinical characteristics of the sample studied (n=967)

Variable	Category	Number of cases	Percentage of the sample
Age, years (mean 49.6±13.8, rank 18–87)	18–30	99	10.2
	30–45	262	27.1
	45–60	406	42.0
	60–75	169	17.5
	>75	30	3.1
Sex	Male	358	37.1
	Female	608	62.9
Educational level	Can read and write	88	9.1
	Primary	334	34.5
	Secondary	359	37.1
	University	186	19.2
ICD-10 diagnosis	Schizophrenia	179	18.5
	Bipolar disorder	118	12.2
	Depressive disorder	462	47.8
	Anxiety disorders	160	16.5
	Personality disorders	30	3.1
	Other diagnoses	18	1.9
History of psychiatric admissions (59.6% involuntary)	No	641	66.3
	1	121	12.5
	2	68	7.0
	3	51	5.3
	≥4	86	8.9
Psychiatrists, n (mean 2.7±2.0, rank 1–15)	1	323	33.4
	2	259	26.8
	3	147	15.2
	4	79	8.2
	≥5	159	16.3
Psychotropic drugs (mean 2.9±1.4 drugs, rank 0–8, polypharmacy 86.2%)	No drugs	21	2.2
	One drug	128	13.2
	Two drugs	260	26.9
	Three drugs	246	25.4
	Four drugs	172	17.8
	Five or more drugs	140	14.5
Treatment	Antidepressants	667	69.0
	Tricyclics	33	3.4
	SSRIs	502	51.9
	SNRIs	340	35.2
	Benzodiazepines	763	79.0
	Antipsychotics	327	33.8
	Conventional	48	5.0
	Atypical	315	32.6
	Mood stabilizers	275	28.4
	Anticholinergics	43	4.4
MMAS-8, (mean 6.3±1.6, rank 0.5–8)	Low adherence (<6)	269	28.3
	Medium adherence (6–<8)	444	46.8
	High adherence (= 8)	236	24.9
CPS, preferred role
Active	Active–active	11	1.1
	Active–collaborative	54	5.6
Collaborative	Collaborative–active	23	2.4
	Collaborative–passive	602	62.3
Passive	Passive–collaborative	246	25.4
	Passive–passive	31	3.2
CPS, experienced role
Active	Active–active	0	0.0
	Active–collaborative	3	0.3
Collaborative	Collaborative–active	4	0.4
	Collaborative–passive	208	21.5
Passive	Passive–collaborative	487	50.4
	Passive–passive	265	27.4

Abbreviations: ICD, International Classification of Diseases; SNRIs, serotonin–norepinephrine reuptake inhibitors; SSRIs, selective serotonin-reuptake inhibitors; CPS, Control Preference Scale; MMAS-8, eight-item self-report Morisky Medication Adherence Scale.

Figure 1 Eight-item self-report Morisky Medication Adherence Scale levels of adherence according to concordance between preferred and experienced participation in decision making.

Table 2 Distribution of preferred and experienced participation, the congruence between both roles, and the relationship with adherence to treatment

	n	%	χ^2	P	High adherence	Medium adherence	Low adherence	χ^2	P
Preferred role
Active	64	6.7			20.3%	40.6%	39.1%
Collaborative	610	64.3	496.02	0.000	24.1%	45.6%	30.3%	11.28	0.024
Passive	275	29			27.6%	50.9%	21.5%
Experienced role
Active	3	0.3			33.3%	66.7%	0
Collaborative	205	21.6	926.87	0.000	26.3%	46.8%	26.8%	1.67	0.796
Passive	741	78.1			24.4%	46.7%	28.9%
Congruence
Matched	486	50.3	0.03	0.872	27.5%	49.1%	23.5%	11.66	0.003
Unmatched	481	49.7			22.2%	44.5%	33.3%
Congruence
Active–active	3	0.6			33.3%	66.7%	0
Collab–collab	208	42.8	247.94	0.000	27.8%	50.9%	21.2%	3.04	0.550
Passive–Passive	275	56.6			27.5%	49.1%	23.5%

Abbreviation: Collab, collaborative.