Mindfulness improves negative psychotic symptoms through reducing emotional and social withdrawal

Table 1 Definition of the positive and negative syndrome scale negative subscales

PANSS negative subscale	Definition
Blunted affect	Diminished emotional responsiveness as characterized by a reduction in facial expression, modulation of feelings, and communicative gestures
Emotional withdrawal	Lack of interest in, involvement with, and affective commitment to life’s events
Poor rapport	Lack of interpersonal empathy, openness in conversation, and sense of closeness, interest, or involvement with the others
Social withdrawal	Diminished interest and initiative in social interactions due to passivity, apathy, anergy, or avolition. This leads to reduced interpersonal involvement and neglect of activities of daily living
Difficulty in abstract thinking	Impairment in the use of the abstract-symbolic mode of thinking, as evidenced by difficulty in classification, forming generalizations, and proceeding beyond concrete or egocentric thinking
Lack of spontaneity and flow of conversation	Reduction in the normal flow of communication associated with apathy, avolition, defensiveness, or cognitive deficit
Stereotyped thinking	Decreased fluidity, spontaneity, and flexibility of thinking, as evidenced in rigid, repetitious, or barren thought content

PANSS: Positive and negative syndrome scale.

Table 2 Demographic and clinical features of the sample

	Total sample (n = 52)	IRT (n = 26)	IRT + MBI (n = 26)	Statistics
Age, years	39.71 ± 8.98	40.15 ± 9.38	39.42 ± 6.33	t = 0.292, P = 0.771
Sex
Male	41 (78.8)	21 (80.8)	20 (76.9)	χ2 = 0.115, P = 0.734
Female	11 (21.2)	5 (19.2)	6 (23.1)
Years since diagnosis	14.13 ± 7.66	14.58 ± 8.22	13.69 ± 7.20	t = 0.413, P = 0.682
Education years	12.04 ± 2.08	11.93 ± 1.89	12.15 ± 2.25	t = -0.399, P = 0.691
Diagnosis
Paranoid schizophrenia	23 (44.2)	11 (42.3)	12 (43.2)	χ2 = 0.134, P = 0.999
Undifferentiated schizophrenia	8 (15.4)	4 (15.4)	8 (15.4)
Disorganized schizophrenia	4 (7.7)	2 (7.7)	2 (7.7)
Schizoaffective disorder	11 (21.2)	6 (23.1)	5 (19.2)
Bipolar disorder	4 (7.7)	2 (7.7)	2 (7.7)
Delusional disorder	2 (3.8)	1 (3.8)	1 (3.8)
PANSS
Positive	14.90 ± 5.80	14.69 ± 5.25	15.11 ± 6.40	t = -0.261, P = 0.796
Negative	19.08 ± 4.01	19.16 ± 4.01	19.00 ± 4.09	t = 0.137, P = 0.892
General	36.11 ± 8.61	36.50 ± 9.63	35.74 ± 7.64	t = 0.319, P = 0.751
Total	70.23 ± 15.46	70.85 ± 15.20	69.61 ± 15.90	t = 0.284, P = 0.777

Data are presented as n (%). IRT: Integrated rehabilitation treatment; MBI: Mindfulness-based intervention; PANSS: Positive and negative syndrome scale.

Table 3 Repeated measures analysis of variance on subscales of the positive and negative syndrome scale negative scale

PANSS negative subscale	Factor	F	P	η2
Blunted affect	Treatment	0.67	0.418	0.013
	Time	1.40	0.242	0.027
	Treatment x time	0.72	0.402	0.014
Emotional withdrawal	Treatment	3.01	0.089	0.057
	Time	38.75	< 0.001	0.437
	Treatment x time	25.67	< 0.001	0.339
Poor rapport	Treatment	0.02	0.880	< 0.001
	Time	1.11	0.297	0.022
	Treatment x time	0.12	0.727	0.002
Social withdrawal	Treatment	7.21	0.010	0.126
	Time	10.47	< 0.001	0.264
	Treatment x time	11.78	< 0.001	0.287
Difficulty in abstract thinking	Treatment	0.16	0.692	0.003
	Time	8.05	0.007	0.139
	Treatment x time	0.161	0.248	0.027
Lack of spontaneity and flow of conversation	Treatment	0.37	0.544	0.007
	Time	0.48	0.489	0.009
	Treatment x time	0.12	0.729	0.002
Stereotyped thinking	Treatment	2.32	0.134	0.044
	Time	6.52	0.014	0.115
	Treatment x time	0.01	0.999	< 0.001

PANSS: Positive and negative syndrome scale.

Table 4 Analysis of the interaction components of the repeated measures analysis of variance on subscales of the positive and negative syndrome scale negative

PANSS negative subscale		PRE	POST	F	P	η2
Blunted affect	IRT	2.54 (1.03)	2.77 (0.99)	2.06	0.157	0.039
	IRT + MBI	2.42 (0.94)	2.46 (1.10)	0.06	0.812	0.001
	PRE			0.18	0.296	0.004
	POST			1.12	0.296	0.022
Emotional withdrawal	IRT	3.85 (1.12)	3.69 (1.32)	0.67	0.417	0.013
	IRT + MBI	4.00 (1.36)	2.50 (0.86)	63.75	< 0.001	0.560
	PRE			0.19	0.658	0.004
	POST			14.89	< 0.001	0.230
Poor rapport	IRT	2.38 (0.80)	2.46 (0.90)	0.25	0.622	0.005
	IRT + MBI	2.31 (1.09)	2.46 (1.14)	0.98	0.326	0.019
	PRE			0.08	0.773	0.002
	POST			0.01	0.999	< 0.001
Social withdrawal	IRT	4.08 (1.20)	4.12 (1.24)	0.03	0.857	0.001
	IRT + MBI	3.96 (1.31)	2.65 (0.98)	38.01	< 0.001	0.432
	PRE			0.11	0.742	0.002
	POST			22.20	< 0.001	0.307
Difficulty in abstract thinking	IRT	2.73 (1.18)	2.54 (1.27)	1.39	0.243	0.027
	IRT + MBI	2.73 (1.48)	2.27 (1.18)	8.03	0.007	0.138
	PRE			0.01	0.999	< 0.001
	POST			0.62	0.434	0.012
Lack of spontaneity and flow of conversation	IRT	2.31 (0.88)	2.19 (0.85)	0.55	0.463	0.011
	IRT + MBI	2.42 (1.14)	2.38 (1.06)	0.06	0.806	0.001
	PRE			0.17	0.685	0.003
	POST			0.52	0.474	0.010
Stereotyped thinking	IRT	1.31 (0.55)	1.19 (0.40)	3.26	0.077	0.061
	IRT + MBI	1.15 (0.67)	1.04 (0.20)	3.25	0.078	0.061
	PRE			1.41	0.241	0.027
	POST			3.08	0.086	0.058

Data are presented as n (%). The IRT and IRT + MBI rows show the interaction analysis for the time factor (within subjects). The PRE and POST rows show the interaction analysis for the treatment factor (between subjects). PANSS: Positive and negative syndrome scale; PRE: Pretreatment; POST: Post-treatment; IRT: Integrated rehabilitation treatment; MBI: Mindfulness-based intervention.