DIMENSIONAL SCHIZOPHRENIA: NOT AN EASY TRANSITION

Recently, several authors have argued in favor of extending the less common clinical phenotype of schizophrenia to a vulnerability phenotype of schizophrenia in the general population. It has been proposed that high levels in any of four different symptom dimensions (affective, psychosis, negative and cognitive) would lead to clinical assessment, identification of correlated symptoms in other dimensions and finally, the diagnosis of schizophrenia. Being so, we would expect to find such a dimensional pattern in the previous diagnoses of schizophrenic patients. We examined previous contacts of a large cohort of patients diagnosed, according to the International Classification of Diseases (ICD-10), with schizophrenia (n = 26,163) in public mental health centers of Madrid (Spain) from 1980 to 2008. Of those patients, 56.7% received another diagnosis prior to schizophrenia. Non-schizophrenia diagnoses within the category of ‘schizophrenia, schizotypal and delusional disorders’ were common (F2; 40.0%). The other most frequent prior diagnoses were ‘neurotic, stress-related and somatoform disorders’ (F4; 47.3%), ‘mood disorders’ (F3; 41.4%), and ‘disorders of adult personality and behavior’ (F6; 20.8%). We then examined the probability of progression to schizophrenia, considering also time proximity. The strongest associations were between several F2 spectrum diagnoses with schizophrenia. However, some affective disorders (F3x) were also linked with schizophrenia but anxiety (F4) or personality disorders (F6) were not. Our findings support two of the previously described dimensions (psychotic, affective) in the development of schizophrenia. Several limitations of the dimensional model will be discussed in view of these findings.