***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: IMPORTANCE An increased risk for psychosis is observed in people with hearing impairment . According to the social defeat hypothesis , the long-term experience of exclusion leads to enhanced baseline activity and /or sensitization of the dopamine system and puts the individual at increased risk for psychosis . OBJECTIVE To investigate whether young adults with severe hearing impairment ( SHI ) experience more feelings of social defeat , show greater dopamine release in response to dexamphetamine , and report a stronger subjective reaction to this substance than normal-hearing young adults and to examine whether dopamine release is associated with both self-reported social exclusion and dexamphetamine-induced psychotic experiences . DESIGN , SETTING , AND PARTICIPANTS A sample of 19 participants with SHI and 19 smoking- , age- , and sex-matched healthy controls underwent single-photon emission computed tomography with iodine 123-labeled iodobenzamide as a radiotracer before and after an amphetamine challenge at an academic hospital . EXPOSURES Dexamphetamine sulfate ( 0.3 mg/kg ) administered intravenously . MAIN OUTCOMES AND MEASURES Baseline D2/3 receptor binding and endogenous dopamine release . RESULTS The participants with SHI reported experiencing more feelings of social defeat ( U=109 , z=-2.09 , P=.04 ) and loneliness ( U=87.5 , z=-2.72 , P=<.001 ) than did healthy controls , but they did not differ from healthy controls with regard to baseline psychotic symptoms ( U=156.5 , z=-0.70 , P=.48 ) . There were no significant group differences in baseline D2/3 receptor binding . However , repeated- measures multivariate analysis of covariance with age ( in months ) and tobacco smoking ( in pack-years ) as covariates showed that there was a greater amphetamine-induced striatal dopamine release among the participants with SHI than among the healthy controls ( F1,34=4.55 , P=.04 ) . After amphetamine administration , the participants with SHI reported more changes in affect than the healthy controls , but not a greater increase in psychotic symptoms . Likewise , reports of social exclusion and an increase in psychotic symptoms were not associated with dopamine release . CONCLUSIONS AND RELEVANCE Our study presents preliminary evidence of dopamine sensitization in a socially excluded group of people with hearing impairment . If replicated by future studies in other excluded groups , this finding may have major implication s for our underst and ing of the underlying mechanism and for prevention of psychotic disorders BACKGROUND Childhood risk factors for the development of adult schizophrenia have proved to have only modest and nonspecific effects , and most seem unrelated to the adult phenotype . We report the first direct examination of the longitudinal relationship between psychotic symptoms in childhood and adulthood . METHODS We analyzed prospect i ve data from a birth cohort ( N = 761 ) , in which children were asked about delusional beliefs and hallucinatory experiences at age 11 years , and then followed up to age 26 years .  Structured diagnostic interviews were employed at both ages and self-report of schizophreniform symptoms was augmented by other data sources at age 26 years . RESULTS Self-reported psychotic symptoms at age 11 years predicted a very high risk of a schizophreniform diagnosis at age 26 years ( odds ratio , 16.4 ; 95 % confidence interval , 3.9 - 67.8 ) . In terms of attributable risk , 42 % of the age-26 schizophreniform cases in the cohort had reported 1 or more psychotic symptoms at age 11 years . Age-11 psychotic symptoms did not predict mania or depression at age 26 years , suggesting specificity of prediction to schizophreniform disorder . The link between child and adult psychotic symptoms was not simply the result of general childhood psychopathology . CONCLUSION These findings provide the first evidence for continuity of psychotic symptoms from childhood to adulthood BACKGROUND Research mostly conducted in the UK and northern Europe has established that there are high rates of first-episode psychosis ( FEP ) in large cities and immigrant population s ; moreover , psychosis has been found to be associated with cannabis use and early trauma . The present study aim ed to evaluate the incidence rate of FEP and the distribution of several risk factors ( e.g. age , ethnicity , substance abuse ) in Bologna , Italy . METHOD The Bologna FEP ( BoFEP ) study is an 8-year prospect i ve study . All FEP patients , 18 - 64 years old , consecutively referred to the West Bologna Community Mental Health Centre ( CMHC ) from 2002 to 2009 were evaluated . Sociodemographic information , migration history and clinical data were collected through an ad-hoc schedule . Psychiatric diagnoses were recorded using the Schedule for Clinical Assessment of Neuropsychiatry ( SCAN ) . RESULTS The overall incidence rate ( IR ) in the BoFEP study was 16.4 per 100 000 person-years [ 95 % confidence interval ( CI ) 13.9 - 18.9 ] . The incidence was higher in young people , men and migrants ( MI ) . CONCLUSIONS The IR of FEP found by the Bologna study is lower than that found by other European studies . However , as in other studies , the incidence was higher in certain groups . This heterogeneity has implication s for policy and mental health service development , and for underst and ing the aetiology of psychosis PURPOSE Clinical ly , one of the most consistent clinical findings among migrant patients is an increase in the rate of psychosis . The aim of the present study was to confirm this finding in Belgium by comparing second-generation Moroccan migrant patients with Belgian patients , matched for the variables of age and gender . SUBJECTS AND METHOD We conducted a cross-sectional survey on 272 patients admitted in a psychiatric emergency unit during the year 1998 . We used univariate and multivariate analyses to compare the two subgroups . RESULTS Multivariate analyses showed that migrant patients lived more often with their parental family and that they presented a higher rate of admission for psychotic disorders and a lower rate of employment . DISCUSSION Our findings add to the growing body of results showing increased incidence of psychosis among immigrants to European countries , but several factors have to be taken into account , particularly with regard to selection biases and differences in help-seeking behaviour and in family perception of the mental illness . CONCLUSION Our results are compatible with the hypothesis that unemployment is a contributing factor in the risk for psychosis among migrant groups . Further studies would be needed to better explain some of our results , particularly the role played by the families of migrant patients 
    Output:
    
Across all research design s , the risks of NAPD and SPS were consistently increased among male , not female immigrants from the Maghreb .
Conclusions The marked gender gap in psychosis risk among migrants from the Maghreb appears a consistent finding , foremost among the Moroccan-Dutch .