Epidemiology of Psychosis

Chris Gale

Otago Registrar Training Group

Feb 2011.

Methodologies used.

● Population surveys.● General population.● High risk populations.● Screener and re-interview.

● Case records (raw or capture | release).● Comprehensive national records● Insurance and prescribing● Admission and outpatient

● Complications of psychosis.

Early intervention surveys: CAMEO study. (Cheng, in press)

● Urban and rural Cambridgeshire.

● Number of people referred to early psychosis.

● Early psychosi defined by Melbourne Criteria.● 1 week psychotic symptoms

● Less than six months treatment.

● PANSS score & clinician consensus diagnosis.

● The rate seems to be dependant on age and gender.● This may be an artifact of second

criteria (no treatment)

CAMEO Results.

● Highly variable crude rates around England.

● However, when corrected for age and gender, prevalence of early psychosis around 5 per 10 000.

Contact prevelance and capture-recapture

Atypical Metabolic: 6 to 8 Weeks.

● The average weight gain after 6 to 8 weeks taking olanzapine was 5 to 6 kg,18, 26, which was significantly higher than the average weight gained while taking risperidone (4 kg) or haloperidol (3 kg).

● A significant increase in fasting and postprandial blood glucose levels and the incidence of diabetes The largest effects were seen for olanzapine, then risperidone and haloperidol.

● At 8 weeks, there was a significant increase in insulin level, insulin resistance, and glucose, cholesterol, triglyceride, and C peptide levels across clozapine, olanzapine, risperidone, and sulpiride combined but no significant difference between drugs.

Foley, Arch Gen Psychiatry, in press.

Atypical Metabolic: By 3 to 4 Months.

● Increase in cholesterol and fasting insulin levels was found after 3 to 4 months taking olanzapine in 1 study but not another.

● No significant increase was found in fasting triglyceride, glucose,or leptin levels

● A significant increase in absolute fat mass; percentage of body fat and waist to hip ratio, suggesting central deposition of body fat; and C peptide level while taking olanzapine.

Foley, Arch Gen Psychiatry, in press.

Atypical Metabolics – by six months to one year.

● Gain in intra-abdominal fat was nonsignificantly higher with risperidone (27 cm2) than olanzapine (18 cm2).

● By 1 Year.

● There was no significant difference in weight gain across different antipsychotics.

● This ranking of antipsychotics was reflected in other weight-related changes, such as 4-kg or more weight increase,36 7% or more weight increase, increasing BMI, and the incidence of metabolic syndrome, but not for intra-abdominal fat.

● Orally disintegrating tablets of olanzapine were associated with significantly less weight gain than standard tablets, as was adjunctive reboxetine but not fluoxetine.

● A significant increase in insulin level, insulin resistance, and total and LDL cholesterol, triglyceride, leptin, and ghrelin levels. Weight gain was significantly correlated with insulin and leptin levels

● An elevation in fasting glucose level in 1 study but not in 2 others

Foley, Arch Gen Psychiatry, in press.

Range of average weight gain over 12 months

Olanzapine 10 – 14 kg

Amisulpride 10 kg

Quetiapine 10 kg

Risperidone 8 – 9 kg

Haloperidol 4 – 7 kg

Chlorpromazine 6 kg

Ziprasadone 5 kg

Perphenazine 1 kg.

Prevalence of psychosis?Type Per 10 000 Reference

Contact Early Psychosis 5 CAMEO Study (Cheng, in press)

Contact (non maori) 7.6 Wellington data, MOH (cited by Kake)

Contact (capture | recapture): non maori.

35 Wellington clinical data set (Kake, 2008).

Latent class analysis fully structured interview (lifetime).

20 NZMHS, Gale, submitted.

CIDI screen with clinician recoding,

150 USA NCS-R, Kessler 2005

12-month, clinician reinterview.

14 USA NCS-R. Kessler 2005

Lifetime, clinician reinterview 31 USA NCS-R. Kessler 2005

Fully structured interviews I: clinician reinterview

Symptom profile, Diagnosis psychosis, US NCR

Comorbidity

● 87.9% of respondents with lifetime NAP met criteria for at least one other lifetime disorder

● 74.2% of respondents with 12-month NAP met criteria for at least one other 12-month disorder.

● The highest lifetime odds-ratios are:

● bipolar disorder (11.4)

● OCD (26.0)

● The highest 12-month odds-ratios are:

● panic disorder (14.7)

● drug dependence (15.8)

● Variation in the ORs across disorders is not reliable due to the very wide confidence intervals.

● The ORs with having high comorbidity:

● three or more hierarchy-free diagnoses in addition to NAP

– 30.4 lifetime

– 17.2 12-month

● larger than those associated with any individual disorder.

Disability Clinical Interview.

● Two to four times greater risk of impaired.● Basic Functioning● Cognition● Days out of role● Social function● Work function.

Clinician reinterview...

● Estimated rate non affective psychosis 15/1000 from structured interview → 3/1000 with structured clinical interview.

● Non significant correlation of clinician reassignment of screening question text with reinterview results.

● Delusions and Halluncinations most highly correlated with psychosis.

● BUT

● SCID modified to have first question same as screener in CIDI.

● Very expensive project, not replicated.

Fully structured interviews II: Latent Class analysis

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

Visions Voices Thoughtinsertion

Thoughtcontrol

Telepathy Persecution

Pro

bab

ilit

y

'Psychotic''Hallucinatory''Normal'

Copyright restrictions may apply.

Dutta, R. et al. Arch Gen Psychiatry 2010;67:1230-1237.

Distribution of Patients, Deaths, and Suicides in the 3 Geographic Catchment Areas

Copyright restrictions may apply.

Dutta, R. et al. Arch Gen Psychiatry 2010;67:1230-1237.

Rate Ratios for Suicide According to Sex, Age of Onset, Calendar Period, and Geographic Center

References.● Cheng F, Kirkbride JB, Lennox BR, et al. Administrative incidence of psychosis assessed in an early

intervention service in England: first epidemiological evidence from a diverse, rural and urban setting. Psychol Med. 2010 Dec 23:1-10. [Epub ahead of print]

● Foley DL, Morley KI. Systematic Review of Early Cardiometabolic Outcomes of the First Treated Episode of Psychosis. Arch Gen Psychiatry. 2011 Feb 7. [Epub ahead of print

● Kake TR, Arnold R, Ellis P. Estimating the prevalence of schizophrenia among New Zealand Maori: a capture-recapture approach. Aust N Z J Psychiatry. 2008 Nov;42(11):941-9]