Psychiatric Unit, Virgen del Camino Hospital, Pamplona, Spain
Correspondence: Dr Manuel J. Cuesta, Psychiatric Unit of Virgen del Camino Hospital, E-31008 Pamplona, Spain. Fax + 34 948 429924; e-mail: mj.cuesta.zorita{at}cfnavarra.es
Declaration of interest Funded by the Spanish National Health Service (grant FIS 97/0480).
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ABSTRACT |
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Aims To investigate whether insight changes with time, and how it relates to patients' psychopathology, and to examine the correlations between insight scales in patients with psychoses.
Method Seventy-five consecutively admitted in-patients with schizophrenia, affective disorder with psychotic symptoms, or schizoaffective disorder were examined after remission of an acute episode and at follow-up (>6 months). Three different scales were used to assess insight.
Results To some extent, insight into past episodes improved over time in patients with psychosis, regardless of diagnosis. Few significant relationships between insight and psychopathology remained stable at follow-up. The higher the negative and disorganisation dimensions at baseline, the less did attitudes to treatment vary when tested at follow-up. No predictive value for variability of psychopathological dimensions was found for insight dimensions. The insight scales used were highly intercorrelated, suggesting that they measure the same construct.
Conclusions Insight and psychopathology seem to be semi-independent domains.
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INTRODUCTION |
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In the past decade, interest has increasingly focused on translating definitions of lack of insight into specific instruments, but until now, no consensus has been reached. However, multidimensional models have achieved agreement on the dimensions underlying it, and at least three (non-exclusive) are widely accepted: awareness of illness, awareness of symptoms, and cooperation with treatment.
We carried out a longitudinal study aimed at answering three questions. (a) Is the insight of patients with psychoses stable during the course of psychosis? (b) Are relationships between the psychopathological dimensions and the dimensions of lack of insight at baseline the same as during follow-up? (c) Are insight scales intercorrelated?
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METHOD |
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Procedure and assessment measures
Participants gave informed consent to enter the study. Patients with a
history of an organic central nervous disorder, drug or alcohol misuse in the
past year or learning disability were excluded. The Comprehensive Assessment
Schedule History (CASH; Andreasen et
al, 1992) was used as a semi-structured interview to assess
psychopathology at baseline and at follow-up. Interrater reliability for
positive and negative symptom scales has been reported as good to excellent
(Peralta et al,
1992). Liddle's three-dimensional model
(Liddle, 1987), with the
addition of depressive and manic dimensions, was chosen for the analysis of
psychopathological status.
Three instruments for insight assessment were used: the Scale to Assess Unawareness of Mental Disorder (SUMD) (Amador et al, 1991, 1994), the Insight and Treatment Attitudes Questionnaire (ITAQ) (McEvoy et al, 1981), and three insight items from the Manual for Assessment and Documentation in Psychopathology (AMDP) (Guy & Ban, 1979). Insight assessment took place in two sessions; the AMDP insight items and the SUMD in the first session, and the ITAQ in the second. The SUMD was assessed by M.J.C., AMDP items were scored by M.J.C. and V.P. and the ITAQ by A.Z. For AMDP insight items, high interrater reliability between two raters has been reported previously (Cuesta & Peralta, 1994). Each evaluator was blind to the results of the others.
The SUMD is a 20-item semi-structured interview which evaluates global insight, insight into illness and insight into symptoms. It comprises three ratings each for global insight into current and past illness: general awareness of having a mental disorder, need for psychiatric treatment, and social consequences of the disorder. Moreover, by averaging responses referring to 17 psychopathological signs and symptoms, which were scored on a 5-point scale, four additional scales were obtained: patients' current and past awareness, and current and past attributional patterns. In our study, past ratings referred to the period of recent hospitalisation, and current awareness was rated according to current state (i.e. moderate or severe) of positive and negative symptoms. The psychometric properties of the SUMD scale and comparison with other instruments have been described elsewhere (Amador et al, 1991; Amador & Seckinger, 1997; Baier et al, 1998).
The ITAQ consists of a semi-structured interview of 11 items. Each item is scored from 0 (no insight) to 2 (good insight) and the total score is used as an insight measure. This questionnaire encompasses recognition of mental disorder (first five items) and attitudes to medication, hospitalisation and follow-up evaluation (six items) (McEvoy et al, 1989a).
The third instrument was extracted from the Spanish version of the Manual for Assessment and Documentation in Psychopathology (AMDP; (López-Ibor, 1980). The AMDP is a comprehensive psychopathological inventory of 100 items. Symptoms are rated from 0 (absent) to 3 (severe). Although it is not a specific scale, it includes three items for the assessment of insight (not feeling ill, lack of insight and uncooperativeness), which partly resemble the three insight dimensions reported in David's model (David, 1990; David et al, 1992).
Patients were recruited for follow-up assessment after a period of at least 6 months; they had to have been clinically stabilised for at least 3 months. The same psychopathological and insight assessment procedures were administered at followup. If patients suffered another acute episode, then a further 6 months had to elapse before follow-up.
Statistical analysis
First, we inspected for any possible bias resulting from the fact that the
follow-up sample was smaller, by comparing the baseline epidemiological,
psychopathological and insight measures of patients who had not returned for
follow-up with those who remained in the study. Parametric contrasts between
baseline and follow-up insight scores were used to examine changes in insight
over time in the total sample. To ascertain changes in insight longitudinally
and any influences of patients' diagnosis, repeated measures of multivariate
analysis of variance (MANOVA) were carried out, with diagnosis as the
between-subject factor and time of assessment as the withinsubject factor.
Longitudinal relationships between psychopathology and insight were analysed
in three ways. First, crosssectional Pearson correlation coefficients between
insight and psychopathological variables at baseline and follow-up were
examined. Second, correlations between scores for changes in psychopathology
and changes in insight were obtained. Third, multiple regression analysis
assessed whether insight at baseline predicts a change in psychopathology and
whether psychopathology at baseline predicts a change in insight at follow-up.
A stepwise variable selection method was used; variables were entered into the
model at a probability of F=0.05, and were removed at
F=0.1.
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RESULTS |
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Psychopathological differences among the three groups of people with
psychotic disorders were mostly due to the process of diagnostic
classification. Schizoaffective patients were older (F=3.38,
P0.03) and had had a greater number of episodes (F=8.11,
P
0.0007) than patients with schizophrenia or affective disorders
(Table 1).
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Insight in the total sample and in diagnostic groups
At baseline assessment, a large proportion of patients showed moderate to
severe lack of awareness of having a mental disorder: the figure varied
between 49% and 66%, depending on the instrument used and the item
considered.
Taking the sample as a whole, four SUMD measures showed a significant
improvement over time, after applying the Bonferroni inequality correlation to
account for a high number of statistical tests
(Bland & Altman, 1995). The
P-value for statistical significance was 0.0035, since 14
statistical procedures were run together. Patients improved in past awareness
of mental disorder (t=-3.57, P
0.001), past awareness of
the effect achieved by medication (t=-3.68, P
0.001), and
past awareness of the social consequences of mental disorder
(t=-3.79, P
0.001). There was an improvement in current
awareness of the social consequences of mental disorder (t=-3.53,
P
0.001). The item not feeling ill on the AMDP also
showed improvement over time (t=3.12, P
0.003).
Significant differences between the diagnostic groups were obtained in
three scores on the SUMD scale: current attribution (F=7.66,
P0.002), current awareness of mental disorder (F=10.3,
P
0.001) and current awareness of the social consequences of
mental disorder (F=6.76, P
0.003). In addition, there
were significant differences in two AMDP items: not feeling ill
(F=6.69, P
0.003) and lack of insight (F=7.85,
P
0.001). Post-hoc contrasts demonstrated that patients with schizophrenia
were more unaware than patients with affective disorders, though patients with
schizophrenia were less aware than patients with schizoaffective disorder in
only two insight ratings (current awareness of social consequences of mental
disorder; and not feeling ill (AMDP), both at baseline assessment). No
differences were found between schizoaffective and affective patients.
Significant differences associated with improvement over time were only found
in two SUMD items, namely past awareness of mental disorder (F=11.9,
P
0.002) and past awareness of the social consequences of mental
disorder (F=10.6, P
0.002). There were no significant
diagnosis-by-time interactions (Table
2).
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Dimensions of insight and psychopathological dimensions
Cross-sectional Pearson correlation coefficients were examined between
psychopathological and insight dimensions at both assessment points. The
P-value for statistical significance after Bonferroni correction was
set at 0.15 (corresponding to P
0.002 for 5x14
correlation matrices), since a more liberal statistical criterion is allowed
in exploratory analysis (Bland &
Altman, 1995). At baseline assessment the psychotic dimension was
significantly associated with greater disturbances in both current
(r=0.47, 0.27-0.63, P
0.001) and past attribution of
illness (r=0.43, 0.22-0.59, P
0.001). The negative
dimension was related to greater disturbances in current awareness of mental
disorder (r=-0.41, 0.20-0.58, P
0.001), current awareness
of effect achieved by medication (r=0.41, 0.20-0.58,
P
0.001), current awareness of the social consequences of mental
disorder (r=0.44, 0.23-0.60, P
0.001), and with two items
of the AMDP: not feeling ill (r=0.35, 0.13-0.53, P
0.002)
and lack of insight (r=0.39, 0.17-0.56, P
0.002). The
only item to which the disorganisation dimension was significantly related was
disturbances on current awareness of effect achieved by medication
(r=-0.39, 0.17-0.56, P
0.001). No significant
associations were found between insight scores and affective dimensions. At
follow-up the pattern of associations was rather different, since only
negative and disorganisation dimensions were significantly associated with
failure of insight. The negative dimension was significantly associated with
lack of current awareness of mental disorder (r=0.41, 0.16-0.60,
P
0.002) and not feeling ill (r=0.40, 0.15-0.60,
P
0.002); and the disorganisation dimension with lack of awareness
of past mental disorders (r=0.52, 0.29-0.68, P
0.001),
awareness of effect achieved by medication (current r=0.40,
0.15-0.60, P
0.0002 and past r=0.47, 0.23-0.65,
P
0.002) and current awareness of the social consequences of
mental disorder (r=0.48, 0.24-0.66, P
0.001)
(Table 3).
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To find out whether changes in insight might be accounted for by
improvement in clinical status, correlations between change scores in
psychopathological dimensions (baseline minus follow-up psychopathological
dimensions) and change scores in insight measures (baseline minus follow-up
insight scores) were obtained. All correlation coefficients were lower than
r=0.48 (P0.005), when the critical value for
P
0.005 after Bonferroni correction was
0.0035.
To assess whether variability in psychopathology dimensions and in insight disturbances differed from each other, multiple regression analysis (stepwise method) was used. Specifically, we tested whether insight at baseline predicts any change in psychopathology dimensions over time, and whether psychopathology at baseline predicts change in insight over time. To avoid the use of a large number of statistical procedures regarding insight, the 14 insight measures were condensed through factor analysis, by the principal components method with an oblimin rotation. Two factors were obtained at baseline (76.9% explained variance), representing a general awareness dimension, with high loading on all SUMD items (eigenvalue=9.44, 67.5% explained variance), and a second factor reflecting attitudes to treatment, which had high weightings on the ITAQ total score and the AMDP refusal of treatment item, and moderate loading of the AMDP not feeling ill and the AMDP lack of insight items (eigenvalue=1.31, 9.4% explained variance). Both factors showed a considerable overlap, since they were highly associated (r=-0.42). Factor scores of insight at baseline were included as dependent variables in separate equation regressions and each variance score of the five psychopathological dimensions (baseline minus follow-up scores), as independent variables. Neither of the two insight summary scores predicted changes in psychopathological dimensions. A second set of multiple regression analyses was conducted to test whether psychopathological dimensions at baseline predict change in insight over time. Higher levels of negative dimension at baseline (B=0.33, 0.15-0.50, R2=0.21, F=14.67, P=0.0003) and higher levels of disorganisation dimension at baseline (B=0.21, 0.06-0.35, R2=0.14, F=8.62, P=0.0049) predicted lower degrees of variance in the attitudes to treatment dimension of insight.
Relationships between insight scales
To verify whether baseline insight scores would predict identical insight
scores at follow-up, multiple regressions were performed. Baseline measures of
insight were good predictors of identical followup insight score, ranging
between R2=0.26 and R2=0.44.
R2 coefficients were statistically significant after
Bonferroni correction, with the exception of the AMDP refusal of
treatment item, which did not enter the regression equation
(R2=0.25, P0.059). Correlational analysis
between identical measures of insight at the two assessment points gave
similar results (data shown in bold in the diagonal of
Table 4). Moreover, scales of
insight were highly intercorrelated, both at baseline and at follow-up.
Correlation coefficients ranged from r=0.35 and r=0.86 at
baseline assessment, and between r=0.55 and r=0.89 at
follow-up, except for the refusal of treatment item, which showed few
significant associations with the remaining insight measures
(Table 4).
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DISCUSSION |
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As regards diagnosis, patients suffering from schizophrenia showed poorer insight than patients with affective disorders but few significant differences from schizoaffective sufferers. Our results not only reemphasised that lack of insight is a prevalent feature of functional psychoses, as cross-sectional studies have found (McEvoy et al, 1989a,b; Amador & Strauss, 1993; Cuesta & Peralta, 1994; Amador et al, 1994; David et al, 1995; Jorgensen, 1995; Kemp & Lambert, 1995; Sanz et al, 1998), but also provided evidence of improvement over time in certain dimensions of insight.
There is, at first glance, a contradiction between an improvement in global insight measures in the total sample and the conclusions drawn from the analysis of diagnostic groups, since whenever the three different diagnostic groups were considered, most improvements vanished. Nevertheless, certain aspects of awareness regarding the past episode (unawareness of the effect achieved by medication and unawareness of the consequences of mental disorder) significantly improved in the long term when compared with the baseline assessment. It seems that patients with psychotic disorders were more concerned with particular circumstances of the past episode, such as the need for treatment and the need for admission, than with complete insight into their illness or symptoms. This agrees with the findings of a study which demonstrated an improvement over time on SUMD misattribution of past symptoms only in those patients who had been hospitalised (Smith et al, 1998).
Dimensions of insight and psychopathological dimensions
Psychopathological dimensions and insight did not show an identical pattern
of relationships at the two assessment points, and no cross-sectional
associations between changes in scores of insight and changes in scores of
psychopathological dimensions were found. Only three out of 14 insight ratings
showed stable significant relationships with psychopathological dimensions:
current awareness of mental disorder and the AMDP not
feeling ill item with the negative dimension, and current
awareness of the effect achieved by medication with the disorganisation
dimension. Otherwise, it was found that baseline negative and disorganisation
dimensions seemed to account for the variability in the attitudes to the
treatment dimension at follow-up. However, psychopathological dimensions
seemed to be independent of a general awareness insight dimension, and
baseline insight factor scores were not predictive of any change in
psychopathological dimensions. The data suggest that insight dimensions are
correlated to a certain extent with negative and disorganisation dimensions,
and that the remitting course of insight dimensions differed from that of
positive and affective symptoms. Moreover, there were semiindependent
longitudinal relationships between negative and disorganisation dimensions and
one of the two insight dimensions, since these psychopathological dimensions
showed unidirectional predictive associations with attitudes to
treatment. These semi-independent patterns of associations between the
insight and psychopathological dimensions partly confirm our previous
hypothesis that psychopathological and insight dimensions are unrelated
domains (Cuesta & Peralta,
1994; David et al,
1995). Moreover, studies reporting factor analysis of the whole
range of psychotic symptoms, where the insight dimension was extracted as an
independent dimension with respect to psychotic and affective symptoms
(Peralta & Cuesta, 1994;
van Os et al, 1996) provided support for at least partial independence of insight and
psychopathology. In addition, pooling together this study's baseline
assessments of insight and psychopathology (14 insight baseline scorings and
five psychopathological dimensions) and performing a factor analysis by the
principal components methods, we extracted four factors (76.2% of explained
variance) (data not shown): (by order of appearance) general awareness,
positivenegativedisorganisation, refusal of treatment (loading
significantly only this item), and a depressivemanic factor. However,
other factors contributing to insight, such as preexisting attitudes, cannot
be disregarded in this study, since it has been reported that personality
traits may to some extent explain the variability of insight in schizophrenia
(Lysaker et al,
1999).
An alternative explanation for the scarcity of stable associations may be that the relationships between insight and symptoms are not always linear. To examine this possibility, associations between ITAQ total score and psychopathological domains were inspected using curve-fit analysis procedures, and the curvilinear fits obtained were non-significant.
Unlike other studies (Kim et al, 1997), in this study we detected no associations between affective dimensions and insight. However, other authors have reported that depressed mood enables patients to understand their disorder better (Amador et al, 1991; Sanz et al, 1998; Smith et al, 1998). Two explanations might account for this discrepancy. First, it has been reported that insight instruments are not all equally able to detect associations with depressed mood (Sanz et al, 1998). Second, relationships between depressive mood and increasing awareness of symptoms and disorder may be somewhat tautological, since patients who are more aware of their disturbances are also more likely to be depressed (Amador et al, 1994).
Relationships between insight scales
Results of insight measures at baseline were highly correlated with those
of the same insight measures at follow-up, except for baseline refusal of
treatment (AMDP). However, only weak significant correlations have been
reported in another longitudinal study
(David et al, 1995).
Differences in design between the two studies may account for this
discrepancy, since David and colleagues assessed insight during an acute
episode, and in our study this assessment was performed after remission of the
acute episode. Moreover, insight scales achieved concurrent validity, since,
in the absence of a gold standard for measuring insight, scores
from different scales with an equivalent purpose and content were strongly
associated (Salvador-Carulla,
1996).
Therefore, as far as the insight scales are concerned, it seems that the discrepancies found between studies are due more to methodological factors, such as selection of patients or course and phase of illness, than to great differences between the scales. This suggests that the choice of a particular insight scale is a question of the aims and preferences of investigators or clinicans. Nevertheless, the information gathered through multi-dimensional instruments better reflects the different components of the construct insight, and their use should be encouraged. Those instruments, such as the SUMD and SAI scales (Schedule of Assessment of Insight: David, 1990), permit a deeper understanding of relationships with other psychopathological domains, and, in the case of the SUMD scale, enable us to detect improvement in insight into past episodes. On the other hand, the ITAQ, which includes many items referring to treatment compliance, may be more appropriate for surveillance of some patients. Finally, multi-dimensional instruments provide a privileged approach for research on associations between insight dimensions and putative neurobiological processes.
Limitations
Certain limitations of the present study must be borne in mind. First, the
insight scales were administered blind with respect to each other, except for
the SUMD scale, which was evaluated by only one rater, who was not completely
blind to the assessment of insight with the AMDP inventory. However, when the
sample was split into those patients assessed by the partially blind rater and
those evaluated by the completely blind rater on the SUMD scale, the results
did not change substantially.
Second, the evaluators of psychopathology were not blind to insight assessments; however, it is impossible to assess insight without knowing the psychopathological status. This potential bias could only be solved by means of selfassessment instruments, but all that is available is a brief and limited self-report scale for the assessment of insight (Birchwood et al, 1994).
Third, the period between the two evaluations varied substantially across the sample (between 6 months and 2 years). However, in our study we emphasised the stability of psychotic symptoms, in order to carry out the assessment sessions outside acute episodes.
Fourth, one quarter of the patients in the sample were not available for the second assessment. This is quite usual in follow-up studies of patients with psychosis, but limits the generalisability of our results, since one would suppose that more severely ill patients were more likely to have been lost to follow-up. In this respect, we could not find significant differences in psychopathological backgrounds between those patients who continued, and those who discontinued, the study, except for a slight but significant increase in one insight item (not feeling ill).
Finally, two statistical points should be borne in mind. Certain results from correlational procedures should be considered as exploratory, because of the large number of correlation analyses carried out, and definitive confirmation of insight as independent of symptoms awaits studies using confirmatory factor analysis.
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Clinical Implications and Limitations |
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LIMITATIONS
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Received for publication December 3, 1999. Revision received February 23, 2000. Accepted for publication March 24, 2000.