Deficit schizophrenia: Concept and validity

Abstract

Byline: Sandeep. Grover, Parmanand. Kulhara First effort to distinguish and characterise psychotic illnesses was made by Emil Kraepelin,[sup] [1] who on the basis of observations of longitudinal course, categorised psychotic illnesses into 'dementia praecox' and 'manic-depressive psychosis'. Many attempts were subsequently made to further characterise schizophrenia (dementia praecox), which culminated in the realisation that it is a heterogeneous disorder that has significant variability in clinical profiles, course and outcome. By 1980, to reduce the heterogeneity of this complex disorder, researchers tried to identify homogeneous subtypes in the hope to facilitate the identification of links between symptoms and putative neurobiological basis of aetiology. The division of symptoms as positive or negative and categorisation of schizophrenia as positive and negative subtypes[sup] [2] and type I and type II[sup] [3] became popular. However, researchers noticed that negative symptoms as described by Crow were not inherent to the disorder alone, but may also be due to neuroleptic medications, depression and environmental factors. This ushered in the concept of primary and secondary negative symptoms. To better understand primary negative symptoms and in a quest to homogenise a separate subtype of schizophrenia, Carpenter et al.[sup] [4] gave the concept of deficit and non-deficit schizophrenia. Concept of Deficit Schizophrenia According to Carpenter et al. ,[sup] [4] the term 'deficit symptoms' should be used to refer specifically to those negative symptoms that are present as enduring traits. According to these authors, deficit symptoms may be present during and in-between episodes of exacerbation of positive symptoms. These deficit symptoms occur regardless of the patient's medication status and are not specifically responsive to anticholinergic drugs or antipsychotic drug withdrawal. It was further conceptualised that the presence of poor premorbid adjustment preceding initial psychotic episode may be manifestations of the deficit syndrome. In contrast, in non-deficit type of schizophrenia, negative symptoms may be present but demonstrate greater fluctuation, lack of persistence and temporal association with possible underlying causes like dysphoric states, drug status, etc. The patient with deficit symptoms may also have changes in symptom intensity and superimposed secondary negative symptoms, but a core of primary and enduring negative symptoms must be present. According to Carpenter et al. ,[sup] [4] this approach to deficit symptoms requires clinical judgment based on longitudinal observation rather than a cross-sectional assessment to establish the presence or absence of the symptoms. To further stress their concept, they operationalised the diagnostic criteria for deficit schizophrenia, which is shown in [Table 1]. Carpenter et al. conceptualised that those patients who met only criterion 1 can be designated as schizophrenia without negative symptoms . Patients, who meet criteria 1 and 2 and possibly 4, but not criterion 3, can be designated as schizophrenia with secondary negative symptoms . Only those patients who satisfy all four criteria should be designated as schizophrenia with deficit syndrome . Those patients meeting criteria 1, 2 and 3, but not criterion 4, could either be schizophrenia with primary, non-enduring negative symptoms though these patients with passage of time may satisfy full criteria for schizophrenia with deficit syndrome and thus become schizophrenia with deficit syndrome . To further distinguish deficit syndrome from primary, non-enduring negative symptoms, the authors[sup] [4] suggested certain conditions for those patients who meet criteria 1, 2 and 3, but not criterion 4 for schizophrenia with deficit syndrome. It was recommended that patients who had two or more prior periods of primary negative symptom (criteria 1, 2 and 3 for schizophrenia with deficit syndrome) followed by at least 3 months of remission of negative symptoms and where the current period of primary negative symptoms is of duration of 4 months or less should be considered to have primary deficit state. …