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Scale for Lifetime Course of Psychotic Illness: A longitudinal scale for psychotic illnesses Dr V Balain1, Dr L Palaniyappan1, Dr R Dangi2, Prof P Liddle1 1. University of Nottingham 2. Nottinghamshire Healthcare NHS Trust Background: Quantifying psychiatric signs and symptoms in psychotic illness has always been a challenge. The care provided to patients with psychiatric illnesses has changed with time. Pioneers of classification of psychiatric illnesses (Kahlbaum, Kraepelin, Bleular) observed patients in asylums over long periods of time. In the last thirty years asylum care has given way to community based care. Most of the patients with chronic psychotic illnesses who would have earlier been in asylums are now cared for in the community or residential settings under the care of rehabilitation services. Mental health professionals practicing today are not able to observe patients in the community over long periods as patients are reviewed at specific intervals or at the time of crisis. Most rating scales currently available for psychotic illnesses are cross sectional e.g. Positive and Negative Symptom Scale (PANSS; Kay 1991), Scale for Assessment of Negative Symptoms (SANS ; Andreason 1984a), Brief Psychiatric rating Scale (BPRS; Overall & Gorham 1962). Although they can be repeated over a period of time to measure change in symptomatology, they fail to provide longitudinal picture of various symptoms which patients with psychotic illnesses experience. Particular challenge has been to devise a scale which measures lifetime prevalence of signs and symptoms in patients with psychotic illnesses. We aim to develop and test a new scale which can inform clinicians working in rehabilitation services about the persistence of symptom factors of psychotic symptoms over the lifetime course of illness. Kraepelinian dichotomy has dominated the classification of psychotic illness and has provided the foundation for classification for over a century. Current evidence fails to provide a point of rarity between psychotic illnesses (Peralta et al 2007; Craddock et al 2005; Crow 1995). Therefore the move is towards dimensional approach to psychotic illnesses, away from concepts of Kraepelinian dichotomy. We aim to develop this scale for patients with a diagnosis of schizophrenia, schizoaffective and bipolar affective disorder type 1, based on continuum diagnosis of psychotic illnesses. These patients constitute majority of patients under the care of rehabilitation services. Aim: To test inter-rater reliability and external validity of the new Scale for Lifetime Course of Psychotic Illness (Addendum 1). We aim to study whether the total persistence scores or persistence of individual symptom factors can predict cognitive impairment (speed of processing) and subtle thought disorder during period of stability. We also aim to investigate if persistence of psychotic symptoms predicts structural changes in the brain by using VBM (Voxel Based Morphometry) to measure loss of grey matter. Method: We used factor analysis data for nineteen psychotic symptoms which are included in the scale- Signs and Symptoms in Psychotic Illness (SSPI; Liddle et al 2002). Factor analysis of these symptoms revealed five symptom factors which accounted for loading of these symptoms and were included in our scale. The five symptom factors are- Anxiety/depression, Psychomotor poverty, Disorganisation, Reality distortion and Psychomotor excitation. Loss of Insight was added as the sixth symptom factor (Addendum 1). 70 patients with a DSM-IV diagnosis of schizophrenia, schizoaffective and bipolar affective disorder Type 1 disorders were recruited in stable phase of illness. Stability was defined as no change in Global Assessment of Functioning (GAF of DSM-IV; American Psychiatric Association 1994) score for at least 6 weeks. Diagnosis was established by discussions in consensus meetings of co-investigators and using computer programme OPCRIT (McGuffin & Farmer 1991). Their case notes were used to score individual episodes (0, 1, 2 or 9) and persistence of these symptom factors over lifetime (0 to 6, Total 0-36) (Addendum 1). Social and Occupational Functioning Assessment Scale (SOFAS; Goldman et al 1992) was used to assess their social functioning, Digit- symbol test for cognitive functioning and Thought & Language Index (TLI; Liddle et al 2002) to identify subtle thought disorder. Structural 3 Tesla MRI scans of these patients were performed on the day of study participation. Inter-rater reliability was established for total persistence score and individual symptom factors using intraclass correlation (ICC). Two raters scored 25 cases independently after attending training and consensus meetings for scoring. SOFAS score was obtained from videos of patients. Two raters independently scored the videos to establish inter-rater reliability for SOFAS score. Intraclass correlation (ICC) was used to establish interrater reliability. Interrater reliability was achieved using ICC for TLI scores with four independent raters. Data was analysed for distribution and where it was found to be non-normal, log transformation was used and kurtosis & skewness of distribution analysed. To establish external validity Pearson correlation coefficients were calculated for relationship between total persistence & individual symptom factor persistence scores with SOFAS. Correlations were calculated to rule out possible confounding variables (duration of illness & chlorpromazine equivalent doses). Multiple regression was used to identify symptom factors which independently influenced SOFAS scores. Similar analysis was performed to test the hypothesis that persistence of psychotic symptoms leads to impaired cognitive performance (Digit Symbol test score) and subtle thought disorder (TLI scores). Voxel Based Morphometry analysis was done using SPM 8 (Friston 2007) to reorient images, normalise anatomical data and to segment grey matter, white matter & cerebrospinal fluid. Spatial smoothing was applied and an explicit masking technique was used for image analysis. Intracranial volume was introduced as a confounding variable. Grey matter differences were calculated using Total persistence and individual symptom factors as covariates. Results: Interrater reliability analysis- Intraclass correlation (ICC) for six symptom factors and total persistence score ranged from 0.68 to 0.90. ICC for SOFAS was 0.83. This indicated that the scale was reliable. External validity analysis- SOFAS score was significantly correlated with Total persistence and Psychomotor poverty, Disorganisation, Reality distortion & Loss of Insight symptom factors. Multiple regression revealed that Psychomotor poverty and Loss of insight independently had negative relationship with SOFAS scores. The above analysis proves that the scale is reliable and valid measure of persistence of psychotic symptoms. Cognitive impairment analysis (Digit-Symbol test scores) – Correlation coefficient for Total persistence was -0.22 (p=0.033). Multiple regression revealed higher Psychomotor poverty (-0.248 p=0.034) and Reality Distortion (-0.244 p=0.036) predicted poorer performance on cognitive task. Subtle thought disorder (TLI) - Multiple regression showed that there was a negative association between Total persistence and persistence scores of Disorganistion & Loss of insight symptom factors and subtle thought disorder. VBM analysis-Patients with greater persistence scores, with chlorpromazine doses as a nuisance covariate, have less grey matter in frontal lobe, mid cingulate and medial parietal lobe (pFDR=0.048 T =3.14). Greater loss of grey matter is found in midcingulate, medial parietal and temporal lobe in patients with higher scores for Kraepelinian persistence (Disorganisation, Psychomotor poverty, and Reality distortion). Discussion: Scale for Lifetime Course of Psychotic Illness is a reliable scale and also achieved external validity. The persistence scores obtained confirm the importance of negative symptoms (Milev et al 2005) and loss of insight (Sitzer et al 2008) as being the predictors of social functioning. The scores were also informative in predicting the cognitive functioning (Puig et al 2008) and subtle thought disorder (Bowie et al 2008). The scale also informs us about structural changes in the brain related to persistence of psychotic symptoms. This scale can be used to develop better understanding of not only the persistence of psychotic symptoms over lifetime. It also provides individual relapse episode symptom factor data, medications used and duration of these episodes. It is a helpful scale to predict the prognosis and assist clinicians in biopsychosocial recovery of patient. Its use is particularly relevant for rehabilitation psychiatry professionals as it provides a longitudinal picture for patients with often long history of various symptoms of psychotic illness. This scale helps in providing information about their illness to patients and a relative in a non-stigmatising way as it does not use any diagnostic ‘pigeon holes’.