S132. SAMPLING BIAS IN STUDIES OF FIRST-EPISODE PSYCHOSIS – A FOLLOW-UP STUDY

Abstract Background Attrition rates and sampling bias in controlled clinical studies are a concern when evaluating the relevance of the results to a specific patient population in a real-life clinical / treatment setting. Dropout rates in studies on psychotic disorders are high and many eligibility criteria may lead to bias in study samples. We wanted to analyze how representative are the patient samples typically included in first-episode psychosis studies such as the Turku Early Psychosis (TEPS) study by using a platform of 3772 consecutive admissions to clinical psychiatric services of Turku Psychiatry. Methods TEPS study was started in 2011 as a part of a larger study on psychosis treatment processes in Turku Psychiatric services. Each patient, inpatient and outpatient, went through initial clinical screening by the treatment group which was followed by a structured evaluation if the screen for first-episode psychosis was positive. Between Oct 2011 and June 2016 there were 195 patients with first-episode psychosis (FEP) suitable to the TEPS study. Of them 102 were willing and 93 were not willing to participate or were not reached in a baseline structured evaluation. Using patient records, we compared if these two groups differed in terms of clinical variables, treatment or prognosis during a 1-year follow-up. Time of hospital stay, involuntary vs. voluntary admission, coercive measures during the hospital care, re-hospitalizations and drop-out from the clinical care during the follow-up were used as outcomes. Results Non-participating (NTP) group had higher rate of involuntary care than participating (TP) group (70 % vs 62 %) as well as higher rate of coercion during the treatment and higher rate of re-admissions during the follow-up than the TP group (36 % vs 22 % and 41 % vs 34 %, respectively) but these differences did not reach statistical significance. During the one-year follow-up NTP group had a significantly higher rate of dropping out from the clinical care than participating TP group (48 % vs 30 %, p=0.01). NTP group had also higher rate of dropping out of clinical treatment mainly because of patient non-adherence (33 % vs 16 %, p=0.03). Discussion Nearly half (47 %) of the intent-to-study FEP patients were not reached or declined to participate in our study. Non-participating patients had a slightly more severe illness and poorer treatment adherence during one-year follow-up. The clinical differences were not as marked as we expected. E.g. involuntary care, inpatient care and more coercion during the follow-up were not significantly different between NTP and TP groups. Nevertheless, the data suggest considerable differences between participating and non-participating patients with first-episode psychosis which should be taken in to account when evaluating the generalizability of the results for an unselected group of psychotic patients in ‘real-life’ clinical care.

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Exploring the relationship between recency and frequency of cannabis use and diminished expression and apathy as two dimensions of negative symptoms in first episode psychosis. A one-year follow-up study

Schizophrenia Research ◽

10.1016/j.schres.2021.08.004 ◽

2021 ◽

Vol 236 ◽

pp. 89-96

Author(s):

Henrik Myhre Ihler ◽

Trine Vik Lagerberg ◽

Siv Hege Lyngstad ◽

Ingrid Melle ◽

Kristin Lie Romm

Keyword(s):

Negative Symptoms ◽

First Episode Psychosis ◽

Two Dimensions ◽

Cannabis Use ◽

First Episode ◽

Follow Up Study ◽

Episode Psychosis ◽

One Year ◽

The Relationship

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Volumetric and morphological characteristics of the hippocampus are associated with progression to schizophrenia in patients with first-episode psychosis

European Psychiatry ◽

10.1016/j.eurpsy.2017.06.006 ◽

2017 ◽

Vol 45 ◽

pp. 1-5 ◽

Cited By ~ 16

Author(s):

R. Sauras ◽

A. Keymer ◽

A. Alonso-Solis ◽

A. Díaz ◽

C. Molins ◽

...

Keyword(s):

Morphological Changes ◽

Morphological Characteristics ◽

First Episode Psychosis ◽

First Episode ◽

Control Group ◽

Subcortical Structures ◽

Episode Psychosis ◽

Left Hippocampus ◽

One Year

AbstractBackground:Abnormalities in the hippocampus have been implicated in the pathophysiology of psychosis. However, it is still unclear whether certain abnormalities are a pre-existing vulnerability factor, a sign of disease progression or a consequence of environmental factors. We hypothesized that first-episode psychosis patients who progress to schizophrenia after one year of follow up will display greater volumetric and morphological changes from the very beginning of the disorder.Methods:We studied the hippocampus of 41 patients with a first-episode psychosis and 41 matched healthy controls. MRI was performed at the time of the inclusion in the study. After one year, the whole sample was reevaluated and divided in two groups depending on the diagnoses (schizophrenia vs. non-schizophrenia).Results:Patients who progressed to schizophrenia showed a significantly smaller left hippocampus volume than control group and no-schizophrenia group (F = 3.54; df = 2, 77; P = 0.03). We also found significant differences in the morphology of the anterior hippocampus (CA1) of patients with first-episode psychosis who developed schizophrenia compared with patients who did not.Conclusions:These results are consistent with the assumption of hyperfunctioning dopaminergic cortico-subcortical circuits in schizophrenia, which might be related with an alteration of subcortical structures, such as the hippocampus, along the course of the disease. According with these results, hippocampus abnormalities may serve as a prognostic marker of clinical outcome in patients with a first-episode psychosis.

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Diagnostic Stability and Clinical Characteristics in First-episode Psychosis

European Psychiatry ◽

10.1016/s0924-9338(09)71352-5 ◽

2009 ◽

Vol 24 (S1) ◽

pp. 1-1

Author(s):

D. Berge ◽

A. Mane ◽

P. Salgado ◽

O. Vilarroya ◽

A. Merino ◽

...

Keyword(s):

First Episode Psychosis ◽

First Episode ◽

Schizophreniform Disorder ◽

Schizophrenia Spectrum Disorders ◽

Diagnostic Stability ◽

Episode Psychosis ◽

Hospitalization Period ◽

Wide Variability ◽

One Year

Introduction:Diagnostic stability in first-episode psychosis shows a wide variability between studies. Amini and cols reported a 50% rate of patients schizophreniform disorder shifting to schizophrenia during the first 12 months period. We report the preliminary follow-up results of our recently ongoing first- episode psychosis unit.Methods:Forty-six patients admitted for a first-episode psichosis to our Inpatient Psychiatric Unit from January 2006 to January 2008 were recruited. Clinical and socio-demographic characteristics were registered during admission period and during the follow-up period.Results:At admission 52% of the first-episode subjects had a diagnosis of psychosis NOS and 32% a schizophreniform disorder diagnosis. after discharge, most of the patients (72%) had a diagnosis of schizophreniform disorder, 16% psychosis NOS and 8% brief psychotic disorder. Six months later, half of the followed-up patients had a schizophreniform disorder diagnosis, and 23% had a diagnosis of schizophrenia. 30% of the patients were drop-outs, mainly referred to other out-patient services. Patients shifting to schizophrenia were younger, predominantly male (75% vs 50% in non-schizophrenia shift), had a lower proportion of university studies and presented a longer hospitalization period at admission. No differences in familial history of psychosis and cannabis use were found. after one-year follow-up period, 50% preserved a schizophreniform disorder diagnosis and 30% were diagnosed as schizophrenia.Conclusions:Schizophrenia spectrum disorders have a high stability in first-episode psychosis during first year follow-up. as in previous studies, male gender is one of the factors that best predicts the shift to schizophrenia.

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