Low prevalence of psychoses among the Hutterites, an isolated religious community.
OBJECTIVE
The authors estimated the prevalence of psychoses among the Hutterites in Manitoba, Canada, who lived in 102 communal farms or colonies. The study stemmed from an earlier epidemiological survey of North American Hutterite colonies (1950-1953), in which a low prevalence of psychoses was documented.


METHODS
Psychiatrically ill individuals identified during the previous survey were rediagnosed with DSM-IV criteria. A current provincial health insurance claims database was queried anonymously for the period June 1992-May 1997, and the prevalence rate of disease among Hutterites, identified by distinctive surnames and unique postal addresses, was compared with the rate in the entire population of the province of Manitoba and in a comparison group of persons with Hutterite surnames but with addresses outside the Hutterite colonies.


RESULTS
The annual prevalence of schizophrenia among the communal Hutterites, estimated from the database search by using ICD-9 criteria, was consistent with the prevalence found in the prior epidemiological survey (annual mean of 1.2/1,000 population, compared with 1.3/1,000 in the prior survey). The database search yielded a significantly lower prevalence for schizophrenia and other functional psychoses among communal Hutterites as well as among the comparison group, compared to the total Manitoba population. There was also lower prevalence for affective psychoses and adjustment reaction disorders among the communal Hutterites, compared to the total Manitoba population. Rates for neurotic disorders were elevated both among the communal Hutterites and the comparison group.


CONCLUSIONS
The prevalence of specific psychoses was reduced among the Hutterites, although neurotic disorders were more prevalent. These findings suggest some specificity, although possible artifacts such as ascertainment bias must be considered. Further research is needed to examine genetic and environmental factors that may contribute to reduced prevalence of specific psychoses among the Hutterites.
Nimgaonkar
V L
VL
Department of Psychiatry, University of Pittsburgh School of Medicine, PA, USA. nimga+@pitt.edu
Fujiwara
T M
TM
Dutta
M
M
Wood
J
J
Gentry
K
K
Maendel
S
S
Morgan
K
K
Eaton
J
J
D017668:Age of Onset; D001714:Bipolar Disorder / Q000453:epidemiology / Q000235:genetics; D002170:Canada / Q000453:epidemiology; D004641:Emigration and Immigration / Q000706:statistics & numerical data; D005190:Family; D018703:Founder Effect; D005828:Genetics, Population; D006801:Humans; D008350:Manitoba / Q000453:epidemiology; D009497:Neurotic Disorders / Q000453:epidemiology / Q000235:genetics; D015995:Prevalence; D011618:Psychotic Disorders / Q000453:epidemiology* / Q000235:genetics*; D012559:Schizophrenia / Q000453:epidemiology / Q000235:genetics; D012737:Sex Factors; D014481:United States / Q000453:epidemiology