NO DIFFERENCE BETWEEN VOLITIVE AND EXPRESSIVE NEGATIVE SYMPTOMS FOR EARLY TREATMENT RESPONSE IN FIRST EPISODE OF PSYCHOSIS ANTIPSYCHOTIC NAIVE PATIENTS

Abstract Background Negative symptoms are associated with a range of poor clinical and real-life functioning outcomes in people with schizophrenia. The division of negative symptoms into two separate factors, named “expressive deficits” and “social amotivation” could enable more accurate analysis and the development of new therapeutic tools. We aim to investigate whether the different symptoms that make up the negative dimension at baseline differently predict treatment response in first episode psychosis (FEP) antipsychotic naïve patients. Methods Patients with FEP (n=80), without previous use of antipsychotics, were recruited at an emergency service in São Paulo, Brazil, between 2014 and 2019. Individuals were assessed at admission and after 10 weeks of follow-up. Patients with schizophrenia, schizoaffective disorder and schizophreniform disorder were included. The diagnosis was confirmed using the Structured Clinical Interview for DSM-IV Disorders (SCID-I). Patients were evaluated with the Positive and Negative Syndrome Scale (PANSS) at the baseline and after 10 weeks of treatment. The “expressive deficits” factor was defined as the sum of the six following items of the PANSS: N1 (blunted affect), N3 (poor rapport), N6 (lack of spontaneity and flow of conversation), G5 (mannerisms and posturing), G7 (motor retardation), G13 (disturbance of volition). The “social amotivation” factor was defined as the sum of N2 (emotional withdrawal), N4 (passive/apathetic social withdrawal) and G16 (active social avoidance). To evaluate treatment response, we used the difference between the PANSS score at baseline and after ten weeks of follow-up (delta-PANSS). We performed three linear regressions, one using the “expressive deficits” factor, one using the “social amotivation” factor and another using the total negative symptom score at baseline. Results The mean age was 26.01 years old (SD ± 7.2), and the majority was male (58.75%). “Expressive deficits” (p=0.005, R-squared=0.084, F-test=8.28, β=8.24, df=78), “social amotivation” (p=0.009, R-squared=0,072, F-test=7.14, β=5.59, df=78); and negative symptoms (p=0.002, R-squared=0.105, F-test=10.23, β=9.08, df=78) at baseline behaved similarly in relation to delta-PANSS. All measures of negative symptoms are highly correlated to PANSS total at both time points. Discussion The results were different from our initial hypothesis of worse outcome for patients with higher expressive negative symptoms. We found that negative symptoms overall and both subdomains are highly correlated to PANSS total in acute phase in early stages, what can explain the association to better outcomes with antipsychotic treatment. Longer follow-up can help us to investigate whether differences between the subdomains of negative symptoms can be observed in more stable patients.