Negative and positive self-thoughts predict subjective quality of life in people with schizophrenia

Figures & data

Table 1 Participants’ demographic data

	Schizophrenia	Control	Statistical value	P-value	Effect size
N (men/women)	36 (16/20)	37 (17/20)	x^Citation2=0.02	P=0.90	Ø,0.01
Age (years)	42.86 (9.40)	43.32 (9.77)	t=−0.21	P=0.84	d=0.05
Education (years)	14.03 (1.86)	15.16 (2.15)	u=464.00	P=0.02	r=−0.28
Premorbid IQ (JART)	98.72 (9.69)	109.51 (6.03)	t=−5.70	P<0.01	d=1.34
IQ (WAIS: Vocabulary, Matrix Reasoning)	88.69 (15.66)	105.92 (14.11)	t=−4.94	P<0.01	d=1.16
Duration of illness	16.04 (7.12)
Dose of antipsychotics (mg/day)	444.67 (327.16)
PANSS
Positive syndrome	13.14 (3.59)
Negative syndrome	15.33 (4.14)
CDSS	3.33 (2.92)
DIEPSS	1.47 (1.95)
BACS
Verbal memory	35.39 (12.57)	45.49 (8.91)	u=353.00	P<0.01	r=−0.41
Working memory	16.58 (3.49)	21.11 (3.97)	t=−5.17	P<0.01	d=1.21
Motor speed	67.67 (14.12)	81.03 (11.44)	t=−4.45	P<0.01	d=1.04
Attention and speed of information processing	51.47 (10.47)	66.70 (8.41)	u=146.50	P<0.01	r=−0.67
Verbal fluency (total)	37.39 (10.06)	46.46 (9.12)	t=−4.04	P<0.01	d=0.95
Executive function	16.97 (2.30)	18.76 (1.83)	u=356.00	P<0.01	r=−0.41
Composite score	−1.20 (0.76)
ATQ-R
Negative automatic thought	67.64 (29.62)	46.08 (12.22)	t=4.05	P<0.01	d=0.96
Positive automatic thought	18.19 (6.99)	19.92 (7.67)	u=555.00	P=0.22	r=−0.14
DPS	41.50 (8.70)	35.24 (8.80)	t=3.05	P<0.01	d=0.72
QLS
Interpersonal relationship	24.31 (8.48)	40.19 (8.72)	u=129.50	P<0.01	r=−0.69
Instrumental role	14.89 (7.39)	21.89 (3.11)	u=292.00	P<0.01	r=−0.50
Intrapsychic foundations	24.50 (10.48)	37.35 (6.15)	u=181.50	P<0.01	r=−0.63
Common objects and activities	6.94 (1.41)	8.05 (1.31)	u=412.00	P<0.01	r=−0.34
Total score	70.64 (22.54)	107.49 (15.68)	u=111.00	P<0.01	r=−0.72
SQLS
ME	13.25 (4.95)	10.92 (3.92)	t=2.24	P=0.03	d=0.52
PS	25.14 (12.74)	17.32 (7.91)	t=3.14	P<0.01	d=0.74
SS	9.33 (9.21)	5.87 (4.98)	u=514.50	P=0.09	r=−0.20

Note: Bold values indicate significant differences between two groups at the level of 0.05.

Abbreviations: ATQ-R, Automatic thoughts Questionnaire-Revised; BACS, Brief Assessment of Cognition in Schizophrenia; CDSS, Calgary Depression Scale for Schizophrenia; DIEPSS, Drug-induced Extrapyramidal Symptoms Scale; DPS, Defeatist Performance Belief Scale; JART, Japanese Adult Reading Test; ME, Motivation and Energy; PANSS, Positive and Negative Syndrome Scale; PS, Psychosocial; QLS, Quality of Life Scale; SS, Symptoms and Side effects; SQLS, Schizophrenia Quality of Life Scale; WAIS, Wechsler Adult Intelligence Scale.

Table 2 Relationship between objective quality of life and clinical variables

	Interpersonal relationship	P-value	Instrumental role	P-value	Intrapsychic foundations	P-value	Common objects and activities	P-value	Total	P-value
PANSS
Positive symptom	−0.21	P=0.36	0.05	P=0.84	−0.23	P=0.24	0.13	P=0.59	−0.16	P=0.45
Negative symptom	−0.23	P=0.30	−0.14	P=0.65	−0.44	P=0.07	0.02	P=0.99	−0.34	P=0.09
CDSS
Depression	−0.07	P=0.76	−0.05	P=0.84	−0.29	P=0.14	−0.22	P=0.35	−0.21	P=0.32
DIEPSS
Side effect	−0.38	P=0.14	−0.24	P=0.37	−0.38	P=0.07	−0.34	P=0.14	−0.44	P=0.02
BACS
Verbal memory	0.19	P=0.36	−0.11	P=0.66	0.12	P=0.58	0.27	P=0.22	0.10	P=0.65
Working memory	0.30	P=0.21	0.11	P=0.66	0.16	P=0.46	0.31	P=0.20	0.25	P=0.31
Motor speed	0.35	P=0.14	0.41	P=0.14	0.40	P=0.07	0.34	P=0.14	0.48	P=0.02
Attention and speed of information processing	0.15	P=0.50	0.26	P=0.36	0.30	P=0.14	0.28	P=0.21	0.31	P=0.12
Verbal fluency (total)	0.29	P=0.21	0.17	P=0.64	0.35	P=0.09	0.47	P=0.03	0.36	P=0.08
Executive function	−0.02	P=0.93	−0.02	P=0.90	0.09	P=0.65	−0.002	P=0.99	0.05	P=0.82
Composite score	0.37	P=0.14	0.28	P=0.35	0.40	P=0.07	0.47	P=0.03	0.45	P=0.02
DPS
Defeatist performance belief	−0.08	P=0.76	0.14	P=0.65	−0.02	P=0.93	−0.19	P=0.38	−0.002	P=0.99
ATQ-R
Negative automatic thought	−0.25	P=0.30	−0.28	P=0.35	−0.29	P=0.14	−0.003	P=0.99	−0.32	P=0.10
Positive automatic thought	0.41	P=0.14	0.29	P=0.35	0.36	P=0.08	0.20	P=0.37	0.48	P=0.02

Notes: Bold values indicate significant correlations at the level of 0.05.

Abbreviations: ATQ-R, Automatic Thoughts Questionnaire-Revised; BACS, Brief Assessment of Cognition in Schizophrenia; CDSS, Calgary Depression Scale for Schizophrenia; DIEPSS, Drug-induced Extrapyramidal Symptoms Scale; DPS, Defeatist Performance Belief Scale; PANSS, Positive and Negative Syndrome Scale; QLS, Quality of Life Scale.

Table 3 Relationship between subjective quality of life and clinical variables

	ME	P-value	PS	P-value	SS	P-value
PANSS
Positive symptom	0.13	P=0.51	0.18	P=0.68	0.32	P=0.17
Negative symptom	0.35	P=0.11	0.03	P=0.95	−0.01	P=0.96
CDSS
Depression	0.30	P=0.16	0.56	P<0.01	0.32	P=0.17
DIEPSS
Side effect	0.17	P=0.41	−0.05	P=0.95	0.14	P=0.55
BACS
Verbal memory	−0.01	P=0.98	0.11	P=0.95	−0.10	P=0.68
Working memory	−0.26	P=0.20	−0.16	P=0.68	−0.26	P=0.19
Motor speed	−0.36	P=0.11	−0.31	P=0.25	−0.22	P=0.27
Attention and speed of information processing	−0.28	P=0.18	−0.13	P=0.80	−0.27	P=0.19
Verbal fluency (total)	−0.22	P=0.28	−0.10	P=0.80	−0.27	P=0.19
Executive function	0.09	P=0.67	−0.11	P=0.80	−0.02	P=0.96
Composite score	−0.28	P=0.18	−0.19	P=0.68	−0.29	P=0.19
DPS
Defeatist performance belief	0.34	P=0.11	0.34	P=0.19	0.48	P=0.02
ATQ-R
Negative automatic thought	0.38	P=0.11	0.65	P<0.01	0.55	P<0.01
Positive automatic thought	−0.51	P=0.03	−0.03	P=0.95	−0.32	P=0.17

Notes: Bold values indicate significant correlations at the level of 0.05.

Abbreviations: ATQ-R, Automatic Thoughts Questionnaire-Revised; BACS, Brief Assessment of Cognition in Schizophrenia; CDSS, Calgary Depression Scale for Schizophrenia; DIEPSS, Drug-induced Extrapyramidal Symptoms Scale; DPS, Defeatist Performance Belief Scale; ME, Motivation and Energy; PANSS, Positive and Negative Syndrome Scale; PS, Psychosocial; SS, Symptoms and Side effects.

Table 4 Results of the general linear modeling analysis

Response variable	Explanatory variable	Estimate (β)	P-value	GLM used
QLS
Common objects	Composite score	0.15	P=0.02	Gamma
Total score	Side effect	−4.01	P=0.03	Gaussian
SQLS
ME	PAT	−0.34	P<0.01	Gaussian
PS	NAT	0.21	P<0.01	Gaussian
	Depression	1.51	P=0.03	Gamma
SS	NAT	0.01	P<0.01

Abbreviations: GLM, generalized linear model; ME, Motivation and Energy; NAT, negative automatic thought; PAT, positive automatic thought; PS, Psychosocial; QLS, Quality of Life Scale; SQLS, Schizophrenia Quality of Life Scale; SS, Symptoms and Side effects.

KatschnigHSchizophrenia and quality of lifeActa Psychiatr Scand2000102s4073337

 Web of Science ®Google Scholar