Affective psychosis and Prader-Willi syndrome.
One in six adults with Prader-Willi syndrome has affective psychosis—screen and refer early.
01Research in Context
What this study did
Doctors looked at the adults with Prader-Willi syndrome (PWS) living in one English county.
They gave full psychiatric exams to see who had mood problems, fears, or psychotic symptoms.
What they found
One in six adults (17 %) had affective psychosis—mood swings plus hallucinations or delusions.
No one in the group had simple anxiety or phobic disorders.
This rate is far higher than in other genetic causes of intellectual disability.
How this fits with other research
Nine years later the same team followed the same people (S et al. 2007). They saw repeated mood episodes, especially in those with the maternal UPD subtype, and warned that standard mood drugs can backfire.
Valdes et al. (2018) used the same case-series method in Williams syndrome and also found hidden major depression with psychosis, showing the pattern repeats across syndromes.
Pakenham et al. (2004) looked at youths with ID and argued most early “psychosis” labels get overturned after careful review. That youth caution does not clash with A et al.—the PWS adults kept their psychosis diagnosis, highlighting age and syndrome matter.
Why it matters
If you serve adults with PWS, add a quick mood-psychosis screen to every annual plan. Watch for sudden belief changes, hallucinations, or sleep-cycle shifts. Early psychiatry referral and team talks can cut crisis admissions and keep community placements stable.
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02At a glance
03Original abstract
Previous studies have demonstrated that maladaptive behaviours are common amongst adults with Prader-Willi syndrome (PWS). Case reports have also previously demonstrated that psychosis can occur amongst adults with PWS. The present study was undertaken in order to gain a better understanding of the psychopathology of the psychosis of PWS. Twenty-three out of 25 adults identified with PWS living in Northamptonshire, UK, agreed to participate. Comprehensive psychiatric assessments (using the PPS-LD), and measures of adaptive and maladaptive behaviours (using the AAMR-ABS) were completed. Comparisons were made for the prevalence of psychiatric disorders against those from a previous epidemiological study of adults with intellectual disability of other aetiologies from a neighbouring county. The PWS group was found to have higher rates of affective disorders (a point prevalence of 17.4%), in which psychotic symptoms were common, but similar rates of schizophrenia/delusional disorders (4.3%) compared with the comparison group. Behaviour disorders were also common. Surprisingly, none of the PWS group was found to have generalized anxiety or phobic disorders. The diagnostic criteria for the episodes including psychotic symptoms are explored. The high rates of affective disorders is of clinical (i.e. treatment) importance as well as being of academic interest with regard to the genetics of psychiatric disorders.
Journal of intellectual disability research : JIDR, 1998 · doi:10.1046/j.1365-2788.1998.4260463.x