First Admission For Psychosis Research Articles

Long-Term Course of Remission and Recovery in Psychotic Disorders.

Understanding prognosis is critical to anticipating public health needs and providing care to individuals with psychotic disorders. However, the long-term course of remission and recovery remains unclear. In this study, the most common trajectories of illness course are described for a cohort of individuals followed for 25 years since first admission for psychosis. Participants are from the Suffolk County Mental Health Project, an epidemiological study of first-admission psychosis. Data for the present study was collected from six follow-ups, with 311 individuals assessed at the 25-year follow-up. Common patterns of remission and recovery were assessed in the baseline cohort of 591 individuals and the subsample from the 25-year follow up. In the baseline cohort and the 25-year subsample, the most common trajectory for individuals with schizophrenia spectrum disorders was no remission and no recovery. Among individuals with other psychotic disorders, in both the baseline and 25-year cohorts, the modal pattern was one of intermittent remission and recovery. Individuals with other psychotic disorders were more likely to experience stable remission (15.1%) and stable recovery (21.1%), outcomes that were rare among individuals with schizophrenia spectrum disorders (0% and 0.6%, respectively). The modal longitudinal pattern for individuals with other psychoses is one of multiple transitions into and out of symptomatic and functional recovery. Engagement in a long-term health care plan may help individuals detect and respond to these changes. Sustained remission and recovery are rare among people with schizophrenia spectrum disorders. Efforts should be directed toward developing more effective treatments for this population.

Long-term trajectories of clinical staging in first-episode psychosis and their associated cognitive outcome: A 21-year follow-up study

Cognitive deficits are already present before psychosis onset but are a key feature of first-episode psychosis (FEP). The objective of this study was to investigate the cognitive outcomes of a cohort of FEP patients who were diagnosed using the clinical staging approach and were followed for up to 21 years.We analyzed data from 173 participants with first-admission psychosis who were followed-up for a mean of 20.9 years. The clinical staging assessment was adapted from the clinical staging framework developed by McGorry et al.1 Cognitive assessment was performed using the MATRICS Consensus Cognitive Battery (MMCB) at the end of follow-up.FEP patients who were longitudinally diagnosed in the lowest clinical stages (stages 2A and 2B) showed better performance in attention, processing speed, and MCCB overall composite score than those in the highest clinical stages (stages 4A and 4B). There was a significant linear trend association between worsening of all MCCB cognitive functions and MCCB overall composite score and progression in clinical staging. Furthermore, the interval between two and five years of follow-up appears to be associated with deficits in processing speed as a cognitive marker.Our results support the validation of the clinical staging model over a long-term course of FEP based on neuropsychological performance. A decline in some cognitive functions, such as processing speed, may facilitate the transition of patients to an advanced stage during the critical period of first-episode psychosis.

A clinical staging model of psychotic disorders based on a long-term follow-up of first-admission psychosis: A validation study

We examined the empirical validity of a staging model of psychotic disorders primarily based on their long-term course. The model distinguished 6 consecutive stages (2A, 2B, 3A, 3B, 4A, 4B) based on symptom recurrence, persistence and progression, such as functional decline. We analyzed data from 243 participants with first-admission psychosis who were followed-up for a mean of 20.9 years and assessed for 22 baseline variables, 23 construct-related variables and 31 outcome variables. Later stages scored significantly poorer than early stages on most validators by showing generally medium to large effect sizes and a dose-response pattern, thus confirming the validity of the model. For each set of validators, differences between consecutive stages were especially evident for stages 2 and 3A, although many variables from each validation realm also differentiated between the consecutive stages 3A and above. Baseline predictors including familial load of schizophrenia, neurodevelopmental impairment, childhood adversity, treatment delay, negative symptoms, neurological impairment and poor early response to treatment, independently accounted for 49.9% of the variance of staging. A staging model of psychosis based primarily on its long-term course has sound construct, outcome and predictive validity, which may inform about stage indicators and predictors of clinical stages from psychosis onset.

Long-Term Outcomes of First-Admission Psychosis: A Naturalistic 21-Year Follow-Up Study of Symptomatic, Functional and Personal Recovery and Their Baseline Predictors.

This study was aimed at characterizing long-term outcomes of first-admission psychosis and examining their baseline predictors. Participants were assessed at baseline for 38 candidate predictors and re-assessed after a median follow-up of 21 years for symptomatic, functional, and personal recovery. Associations between the predictors and the outcomes were examined using univariate and multivariate Cox regression models. At baseline, 623 subjects were assessed for eligibility, 510 met the inclusion/exclusion criteria and 243 were successfully followed-up (57.3% of the survivors). At follow-up, the percentages of subjects achieving symptomatic, functional, and personal recovery were 51.9%, 52.7%, and 51.9%, respectively; 74.2% met at least one recovery criterion and 32.5% met all three recovery criteria. Univariate analysis showed that outcomes were predicted by a broad range of variables, including sociodemographics, familial risk, early risk factors, premorbid functioning, triggering factors, illness-onset features, neurological abnormalities, deficit symptoms and early response to treatment. Many of the univariate predictors became nonsignificant when entered into a hierarchical multivariate model, indicating a substantial degree of interdependence. Each single outcome component was independently predicted by parental socioeconomic status, family history of schizophrenia spectrum disorders, early developmental delay, childhood adversity, and mild drug use. Spontaneous dyskinesia/parkinsonism, neurological soft signs and completion of high school remained specific predictors of symptomatic, functional, and personal outcomes, respectively. Predictors explained between 27.5% and 34.3% of the variance in the outcomes. In conclusion, our results indicate a strong potential for background and first-episode characteristics in predicting long-term outcomes of psychotic disorders, which may inform future intervention research.

Predicting Long-Term Outcomes in First-Admission Psychosis: Does the Hierarchical Taxonomy of Psychopathology Aid DSM in Prognostication?

The Hierarchical Taxonomy of Psychopathology (HiTOP) is an empirical, dimensional model of psychological symptoms and functioning. Its goals are to augment the use and address the limitations of traditional diagnoses, such as arbitrary thresholds of severity, within-disorder heterogeneity, and low reliability. HiTOP has made inroads to addressing these problems, but its prognostic validity is uncertain. The present study sought to test the prediction of long-term outcomes in psychotic disorders was improved when the HiTOP dimensional approach was considered along with traditional (ie, DSM) diagnoses. We analyzed data from the Suffolk County Mental Health Project (N = 316), an epidemiologic study of a first-admission psychosis cohort followed for 20 years. We compared 5 diagnostic groups (schizophrenia/schizoaffective, bipolar disorder with psychosis, major depressive disorder with psychosis, substance-induced psychosis, and other psychoses) and 5 dimensions derived from the HiTOP thought disorder spectrum (reality distortion, disorganization, inexpressivity, avolition, and functional impairment). Both nosologies predicted a significant amount of variance in most outcomes. However, except for cognitive functioning, HiTOP showed consistently greater predictive power across outcomes-it explained 1.7-fold more variance than diagnoses in psychiatric and physical health outcomes, 2.1-fold more variance in community functioning, and 3.4-fold more variance in neural responses. Even when controlling for diagnosis, HiTOP dimensions incrementally predicted almost all outcomes. These findings support a shift away from the exclusive use of categorical diagnoses and toward the incorporation of HiTOP dimensions for better prognostication and linkage with neurobiology.

Dynamic interplay between life events and course of psychotic disorders: 10-year longitudinal study following first admission.

Life events (LEs) are a risk factor for first onset and relapse of psychotic disorders. However, the impact of LEs on specific symptoms - namely reality distortion, disorganization, negative symptoms, depression, and mania - remains unclear. Moreover, the differential effects of negative v. positive LEs are poorly understood. The present study utilizes an epidemiologic cohort of patients (N = 428) ascertained at first-admission for psychosis and followed for a decade thereafter. Symptoms were assessed at 6-, 24-, 48-, and 120-month follow-ups. We examined symptom change within-person and found that negative events in the previous 6 months predicted an increase in reality distortion (β = 0.07), disorganized (β = 0.07), manic (β = 0.08), and depressive symptoms (β = 0.06), and a decrease in negative symptoms (β = -0.08). Conversely, positive LEs predicted fewer reality distortion (β = -0.04), disorganized (β = -0.04), and negative (β = -0.13) symptoms, and were unrelated to mood symptoms. A between-person approach to the same hypotheses confirmed that negative LEs predicted change in all symptoms, while positive LEs predicted change only in negative symptoms. In contrast, symptoms rarely predicted future LEs. These findings confirm that LEs have an effect on symptoms, and thus contribute to the burden of psychotic disorders. That LEs increase positive symptoms and decrease negative symptoms suggest at least two different mechanisms underlying the relationship between LEs and symptoms. Our findings underscore the need for increased symptom monitoring following negative LEs, as symptoms may worsen during that time.

Apolipoprotein E-ε4 allele predicts escalation of psychotic symptoms in late adulthood

BackgroundResearch on a putative link between apolipoprotein-ε4 allele (APOE-ε4) and schizophrenia has been inconclusive. However, prior studies have not investigated the association between APOE-ε4 and symptom trajectories, nor has the existing literature taken into account the potentially moderating effect of age in genetic association studies. MethodsThe association between APOE-ε4 and four symptom dimensions was investigated in a longitudinal study of 116 individuals with schizophrenia initially assessed during their first admission for psychosis and evaluated five times over the following 20years. A meta-analysis identified 29 case-control studies of APOE-ε4 allele frequency in schizophrenia, which were analyzed using random-effects meta-regression to test the potentially moderating effect of age. ResultsLongitudinal models identified a specific association between APOE-ε4 and symptom trajectories, showing that APOE-ε4 portends worsening severity of hallucinations and delusions in late adulthood among people with schizophrenia, at a rate of a 0.46 standard deviation increase per decade. Meta-analysis showed a significant effect of age: the association between APOE-ε4 and schizophrenia was not detectable in younger people but became pronounced with age, such that APOE-ε4 increased the odds of diagnosis by 10% per decade. ConclusionsTaken together, the meta-analysis and longitudinal analysis implicate APOE-ε4 as an age-related risk factor for worsening hallucinations and delusions, and suggest APOE-ε4 may play an age-mediated pathophysiological role in schizophrenia. The presence of an APOE-ε4 allele may also identify a subgroup of patients who require intensive monitoring and additional targeted interventions, especially in mid-to late-life.

Primary psychosis with comorbid drug abuse and drug-induced psychosis: Diagnostic and clinical evolution at follow up.

The study reports a follow-up assessment of 48 patients with concomitant drug abuse at the first admission for psychosis. We focused on the diagnostic distinction between primary psychosis with concomitant drug abuse and drug induced psychosis, to observe whether the diagnoses are stable over time and whether the clinical course significantly differs. The study examined 25 primary psychotic disorder with comorbid drug abuse and 23 drug-induced psychotic disorder patients. Diagnostic and psychopathological assessments were made at baseline and at follow-up. Mean follow-up period was 4.96 years. Patients with comorbid Drug Abuse exhibited higher scores in the item Unusual Content of Thought at baseline than drug-induced psychotic disorder patients: 5.48 vs 4.39 while the two patients groups did not differ in any of the BPRS items evaluated at follow-up. The primary psychosis with comorbid drug abuse and the substance induced psychosis groups were similar regarding diagnostic stability, and a diagnosis of schizophrenia at follow-up occurred similarly. There was no evidence that Drug Induced psychotic patients' symptoms tend to improve more after cessation of drug abuse. An earlier age of onset was found in primary psychotic patients, particularly for patients diagnosed as affected by schizophrenia at follow up. These results might reflect the uncertainty of the distinction between Primary and Drug Induced Psychosis and the difficulties in applying the DSM IV-TR criteria for diagnosing comorbid drug use disorders and psychotic disorders.

Impact of universal health coverage on urban–rural inequity in psychiatric service utilisation for patients with first admission for psychosis: a 10-year nationwide population-based study in Taiwan

ObjectiveTo examine the disparities in psychiatric service utilisation over a 10-year period for patients with first admission for psychosis in relation to urban–rural residence following the implementation of universal health...

Duration of unspecific prodromal and clinical high risk states, and early help-seeking in first-admission psychosis patients.

Prevention of psychosis requires both presence of clinical high risk (CHR) criteria and early help-seeking. Previous retrospective studies of the duration of untreated illness (i.e. prodrome plus psychosis) did not distinguish between prodromal states with and without CHR symptoms. Therefore, we examined the occurrence of CHR symptoms and first help-seeking, thereby considering effects of age at illness-onset. Adult patients first admitted for psychosis (n=126) were retrospectively assessed for early course of illness and characteristics of first help-seeking. One-hundred and nine patients reported a prodrome, 58 with CHR symptoms. In patients with an early illness-onset before age 18 (n=45), duration of both illness and psychosis were elongated, and CHR symptoms more frequent (68.9 vs. 33.3%)compared to those with adult illness-onset. Only 29 patients reported help-seeking in the prodrome; this was mainly self-initiated, especially in patients with an early illness-onset. After the onset of first psychotic symptoms, help-seeking was mainly initiated by others. State- and age-independently, mental health professionals were the main first point-of-call (54.0%). Adult first-admission psychosis patients with an early, insidious onset of symptoms before age 18 were more likely to recall CHR symptoms as part of their prodrome. According to current psychosis-risk criteria, these CHR symptoms, in principle, would have allowed the early detection of psychosis. Furthermore, compared to patients with an adult illness-onset, patients with an early illness-onset were also more likely to seek help on their own account. Thus, future awareness strategies to improve CHR detection might be primarily related to young persons and self-perceived subtle symptoms.

Clinical significance of auditory target P300 subcomponents in psychosis: Differential diagnosis, symptom profiles, and course

BackgroundReduced auditory target P300 amplitude is a leading biomarker for psychotic disorders, although its relevance for differential diagnosis and link to specific clinical features (symptom profiles, functional impairment, and course) are unclear. This study aims to clarify the clinical significance of auditory target P300 using concurrent and retrospective clinical data from a longitudinal cohort with psychosis. Methods92 cases from an epidemiological study of first-admission psychosis were assessed using an auditory oddball paradigm at 15-year follow-up along with 44 never-psychotic adults. Subcomponents of auditory target P300 amplitude (i.e., a central positive P3a, a parietal positive P3b, and a frontal negative slow wave) were isolated using temporal–spatial principal component analysis. ResultsP3a amplitude was blunted across psychotic disorders relative to non-psychotic adults. P3b amplitude was reduced in schizophrenia specifically, including cases initially misclassified at baseline. The frontal negative slow wave did not distinguish among groups. P3b amplitude reduction was associated with several clinical features at the concurrent assessment, as well as previous time points, including recovery from psychosis even 5years earlier and functioning even 15years earlier. ConclusionsAuditory target P300 amplitude yields both a schizophrenia-specific component (i.e., P3b) and a transdiagnostic psychosis component (i.e., P3a). The P3b component may also shed light on prognosis, real-world functioning, and course, as well as help to reduce misdiagnosis of psychotic disorders. Prospective studies are needed to test whether P3b tracks or predicts clinical status.

An incongruent reality: The N400 in relation to psychosis and recovery

BackgroundCognitive impairments and delusions are hallmarks of schizophrenia, and are thought to be due in part to abnormalities in semantic priming. The N400, a neural measure of semantic processing, is found to be reduced in schizophrenia. However, it is unclear if individuals with other psychoses (e.g., mood disorders or substance abuse with psychotic features) also show this impairment, and whether N400 reduction relates to real-world functioning and recovery. MethodsEighty-nine individuals from the Suffolk County Mental Health Project, a longitudinal study of first-admission psychosis, and 35 healthy adults were assessed using matched, related, and unrelated picture–word pairs to elicit the N400. Patients' real-world functioning, symptomatology, and recovery were tracked since first hospitalization; EEG assessment was completed during year 15 of the study. ResultsParticipants with schizophrenia had slower reaction times and reduced N400 to semantically incongruent stimuli relative to healthy participants. Schizophrenia and other psychoses did not differ on N400, suggesting that N400 abnormalities characterize psychosis broadly. When grouped by recovery status, patients who remained ill had a significantly blunted N400, while those who recovered did not differ from healthy adults. Few patients with schizophrenia achieved recovery; therefore recovery results are limited to the other psychosis group. Furthermore, reduced N400 and increased reaction times correlated with greater psychotic symptoms, worse global assessment of functioning scores, unemployment, and impaired social functioning. ConclusionsAbnormalities in the N400 are not specific to schizophrenia; in addition, the N400 may be a useful neural correlate of recovery and real-world functioning across psychotic disorders.

Different rates of first admissions for psychosis in migrant groups in Paris.

The association between migration and psychosis has been reported in the past decades in many European countries. Despite large-scale migration into France, epidemiological data on the incidence of psychosis in this population are lacking. In this study, we compare the incidence rates of first admission for psychosis among natives and first generation migrants. Two-hundred and fifty-eight patients aged 15+ with first admission for psychosis were identified in the catchment area of the 20th district of Paris between 2005 and 2009. Standardised incidence rates and incidence rate ratios were calculated for migrant and native groups. We found higher rates of admissions for psychosis in the migrant group (IRR 2.9, 95 % CI 0.9-9.8) compared to individuals born in France. Among migrants, incidence was higher in individuals from Sub-Saharan Africa compared to natives (IRR 7.1, CI 95 % 2.3-21.8), whereas the incidence was similar for those from Europe (IRR 1.2, CI 95 % 0.3-5.1) and from North Africa (IRR 1.4, CI 95 % 0.4-5.6). Our findings suggest that Sub-Saharan migrants were identified as the most vulnerable migrant group for developing psychosis in France, but additional work is warranted to confirm these trends.

Who Is Paying the Price? Loss of Health Insurance Coverage Early in Psychosis

Who Is Paying the Price? Loss of Health Insurance Coverage Early in Psychosis

Diagnostic Shifts During the Decade Following First Admission for Psychosis

Diagnostic shifts have been prospectively examined in the short term, but the long-term stability of diagnoses has rarely been evaluated. The authors examined diagnostic shifts over a 10-year follow-up period. A cohort of 470 first-admission patients with psychotic disorders was systematically assessed at baseline and at 6-month, 2-year, and 10-year follow-ups. Longitudinal best-estimate consensus diagnoses were formulated after each assessment. At baseline, the diagnostic distribution was 29.6% schizophrenia spectrum disorders, 21.1% bipolar disorder with psychotic features, 17.0% major depression with psychotic features, 2.4% substance-induced psychosis, and 27.9% other psychoses. At year 10, the distribution changed to 49.8%, 24.0%, 11.1%, 7.0%, and 8.1%, respectively. Overall, diagnoses were changed for 50.7% of study participants at some point during the study. Most participants who were initially diagnosed with schizophrenia or bipolar disorder retained the diagnosis at year 10 (89.2% and 77.8%, respectively). However, 32.0% of participants (N=98) originally given a non-schizophrenia diagnosis had gradually shifted to a schizophrenia diagnosis by year 10. The second largest shift was to bipolar disorder (10.7% of those not given this diagnosis at baseline). Changes in the clinical picture explained many diagnostic shifts. In particular, poorer functioning and greater negative and psychotic symptom ratings predicted a subsequent shift to schizophrenia. Better functioning and lower negative and depressive symptom ratings predicted the shift to bipolar disorder. First-admission patients with psychotic disorders run the risk of being misclassified at early stages in the illness course, including more than 2 years after first hospitalization. Diagnosis should be reassessed at all follow-up points.

Is poor premorbid functioning a risk factor for suicide attempts in first-admission psychosis?

Background While poor premorbid functioning is associated with poorer outcomes in psychotic illnesses, little is known about whether it is also a risk factor for suicide attempts. Objective The current study examined the association of premorbid functioning and suicide attempts in a county-wide cohort of first-admission inpatients. Method Data were derived from participants of the Suffolk County Mental Health Project ( n = 444) over the course of 48-month follow-up. Premorbid functioning was estimated and categorized (good vs. poor/declining) using the Premorbid Adjustment Scale (PAS). Results Poorer premorbid functioning was significantly associated with increased likelihood of a suicide attempt prior to first psychiatric hospital admission. Specifically, 33.0% of participants with poor/declining premorbid functioning had a history of suicide attempts compared to 23.5% with good premorbid functioning. Among participants with a prior attempt ( n = 126), poor premorbid functioning was significantly associated with an increased likelihood of additional attempts during the four years after first hospitalization. Conclusion Identifying those with poor premorbid functioning and prior histories of attempts could help clinicians target high-risk patients. Thus, greater attention to persons with both risk factors may form the basis for early interventions aimed towards reducing the risk for subsequent suicide attempts.

Cannabis and First-Episode Psychosis: Different Long-term Outcomes Depending on Continued or Discontinued Use

Objective: To examine the influence of cannabis use on long-term outcome in patients with a first psychotic episode, comparing patients who have never used cannabis with (a) those who used cannabis before the first episode but stopped using it during follow-up and (b) those who used cannabis both before the first episode and during follow-up. Methods: Patients were studied following their first admission for psychosis. They were interviewed at years 1, 3, and 5. At follow-up after 8 years, functional outcome and alcohol and drug abuse were recorded. Patients were classified according to cannabis use: 25 had cannabis use before their first psychotic episode and continuous use during follow-up (CU), 27 had cannabis use before their first episode but stopped its use during follow-up (CUS), and 40 never used cannabis (NU). Results: The 3 groups did not differ significantly in symptoms or functional outcome at baseline or during short-term follow-up. The CUS group exhibited better long-term functional outcome compared with the other 2 groups and had fewer negative symptoms than the CU group, after adjusting for potential confounders. For the CUS group, the effect size was 1.26 (95% confidence interval [CI] = 0.65 to 1.86) for functional outcome and −0.72 (95% CI = −1.27 to −0.14) for negative symptoms. All patients experienced improvements in positive symptoms during long-term follow-up. Conclusion: Cannabis has a deleterious effect, but stopping use after the first psychotic episode contributes to a clear improvement in outcome. The positive effects of stopping cannabis use can be seen more clearly in the long term.

Antecedents and Patterns of Suicide Behavior in First-Admission Psychosis

Persons with psychotic illnesses have an increased risk for suicide, especially early in the illness. Sufficient knowledge allowing for early recognition is lacking. To describe suicide behaviors before and during the 4 years following first psychiatric hospitalization, examine associations of demographic and psychiatric risk factors, and develop a suicide risk index. Data came from the Suffolk County Mental Health Project, a first-admission cohort (n = 529). Cox regression was used to study associations of risk factors to suicide behaviors; a summary suicide behavior risk index was also tested. Prior to first admission, 28.0% (n = 148) of the cohort had attempted suicide. During the 4-year follow-up, 13.6% (n = 72) of the cohort attempted suicide (29.7% of those with previous attempts and 7.3% making their first attempt) and 3 respondents died of suicide. The significant predictors at index admission of subsequent attempts were prior attempts or ideation, severity of depressive symptoms and thought disorder, lifetime substance abuse, and younger age. Suicide ideation was predicted by the same variables with the addition of insight into illness and with the exception of age at admission. A 3-category risk index was created; 61.1% of those who made a suicide attempt were in the highest risk group (n = 44/72). The current study confirms and extends previous research showing that risk factors early in the course of illness are predictive of subsequent ideation and attempts. The risk index may be a useful adjunct in identifying individuals likely to benefit from preventive interventions.

SOCIAL COGNITION AND NEUROCOGNITION AS INDEPENDENT DOMAINS IN PSYCHOSIS

Objective. To explore whether baseline memory and executive deficits predicted poor social and clinical outcome over the 2 years following a first admission for psychosis, regardless of categorical diagnosis.Method. Cognitive functioning was assessed in first-admitted subjects with psychosis (n=35) with a neuropsychological battery of tests measuring executive, language and memory functions. Social and clinical outcome were assessed at 6-monthly intervals over a two-year follow-up using multiple sources of information.Results. A dose–response relationship was found between visual and verbal memory performance at first admission and clinical outcome over the 2-year follow-up: the poorer the memory performance, the more likely the risk of presenting with psychotic symptoms and rehospitalization. Poor baseline performance on the WCST executive function predicted better medication adherence. No association was found between cognitive performance and occupational or residential outcome.Conclusion. Cognitive performance was a better predictor of clinical than social outcome in this sample of first-episode patients. The association between cognitive deficits and poor social outcome may be more marked in subjects with chronic psychosis than in first-episode subjects. The finding that cognitive deficits predict better medication adherence is in need of further exploration.

Elevated Plasma Dopamine Metabolites in Cannabis Psychosis

Back to table of contents Previous article Next article Letters to the EditorFull AccessElevated Plasma Dopamine Metabolites in Cannabis PsychosisMALCOLM B. BOWERS M.D.JOSHUA T. KANTROWITZ M.D.,MALCOLM B. BOWERS M.D.Search for more papers by this authorJOSHUA T. KANTROWITZ M.D.Search for more papers by this author,Published Online:1 Oct 2007https://doi.org/10.1176/appi.ajp.2007.07010217AboutSectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InEmail To The Editor: Cannabis has received increasing attention as a risk factor for the development of psychotic states (1) . There are relatively little data related to the biochemical profile in cannabis psychosis (2 , 3) . We report on five consecutive cases of first-admission psychosis associated with documented cannabis use. For comparison, we used a consecutive series of first-admission psychosis and a group of nonpsychotic inpatients treated during the same period. We collected plasma for homovanillic acid on the first morning after admission following an overnight fast. The first-admission cannabis psychosis group (N=5) had a mean age of 21.2 years. Urine tests were positive for cannabis subjects on admission. The comparison groups had urine samples negative for cannabinoids on admission. The first-episode psychosis group (N=15) had a mean age of 20.4 years, and the nonpsychotic group (N=17) had a mean age of 32.0 years. The psychosis groups did not significantly differ in age, race, sex, or level of psychosis. The degree of psychosis was rated as moderate on the four positive symptom items of the Brief Psychiatric Rating Scale.Plasma homovanillic acid was measured using gas chromatography mass spectrometry with deuterated internal standards. Homovanillic acid levels were compared using a Student’s t test. Plasma homovanillic acid values were as follows: cannabis psychosis group, 24.8 ng/ml (SD=2.9); first-episode group, 15.1 ng/ml (SD=3.1); and nonpsychotic group, 9.6 ng/ml (SD=2.1). Homovanillic acid values for the cannabis group were significantly higher relative to the first-episode group (p<0.001) and the nonpsychotic group (p<0.001). Homovanillic acid values for the first-episode group were significantly higher when compared with the nonpsychotic group (p<0.001). To our knowledge, this is the first report of elevated plasma homovanillic acid in cannabis-related psychosis, although we are aware of a report of elevated urinary homovanillic acid following cannabis administration to a volunteer population (2) . In this small case series of patients with first-episode psychosis associated with cannabis use, plasma homovanillic acid was significantly higher than values for each of the comparison groups. There are several possibilities for this result. First, plasma homovanillic acid is elevated in a number of newly admitted psychosis patients (4) , which was the case in our first-episode psychosis group. However, plasma homovanillic acid was even higher in the cannabis group. Second, acute cannabis administration can produce increased dopamine activity in animals and humans (2 , 3) . Third, individuals with cannabis psychosis may also have a genetic vulnerability that can lead to increased dopaminergic activity (1) . New Haven, Conn.The authors report no competing interests.This letter (doi: 10.1176/appi.ajp.2007.07010217) was accepted for publication in July 2007.Reprints are not available; however, Letters to the Editor can be downloaded at http://ajp.psychiatryonline.org.