title: Psychiatric hospital beds and prison populations in South America since 1990: does the Penrose hypothesis apply?
abstract: OBJECTIVE
  In 1939, English mathematician, geneticist, and psychiatrist Lionel Sharples Penrose hypothesized that the numbers of psychiatric hospital beds and the sizes of prison populations were inversely related; 75 years later, the question arises as to whether the hypothesis applies to recent developments in South America.
  
  
  OBJECTIVE
  To explore the possible association of changes in the numbers of psychiatric hospital beds with changes in the sizes of prison populations in South America since 1990.
  
  
  METHODS
  We searched primary sources for the numbers of psychiatric hospital beds in South American countries since 1990 (the year that the Latin American countries signed the Caracas Declaration) and compared these changes against the sizes of prison populations. The associations between the numbers of psychiatric beds and the sizes of prison populations were tested using fixed-effects regression of panel data. Economic variables were considered as covariates. Sufficiently reliable and complete data were obtained from 6 countries: Argentina, Bolivia, Brazil, Chile, Paraguay, and Uruguay.
  
  
  METHODS
  The numbers of psychiatric beds and the sizes of prison populations.
  
  
  RESULTS
  Since 1990, the numbers of psychiatric beds decreased in all 6 countries (ranging from -2.0% to -71.9%), while the sizes of prison populations increased substantially (ranging from 16.1% to 273.0%). Panel data regression analysis across the 6 countries showed a significant inverse relationship between numbers of psychiatric beds and sizes of prison populations. On average, the removal of 1 bed was associated with 5.18 more prisoners (95% CI, 3.10-7.26; P = .001), which was reduced to 2.78 prisoners (95% CI, 2.59-2.97; P < .001) when economic growth was considered as a covariate. The association between the numbers of psychiatric beds and the sizes of prison populations remained practically unchanged when income inequality was considered as a covariate (-4.28 [95% CI, -5.21 to -3.36]; P < .001).
  
  
  CONCLUSIONS
  Since 1990, the numbers of psychiatric beds have substantially decreased in South America, while the sizes of the prison populations have increased against a background of strong economic growth. The changes appear to be associated because the numbers of beds decreased more extensively when and where the sizes of prison populations increased. These findings are consistent with and specify the assumption of an association between the numbers of psychiatric beds and the sizes of prison populations. More research is needed to understand the drivers of the capacities of psychiatric hospitals and prisons and to explore reasons for their association.
authors.affiliation: Unit of Social and Community Psychiatry (World Health Organization Collaborating Centre for Mental Health Services Development), Queen Mary University of London, London, England2Department of Psychiatry and Mental Health, Hospital Clínico Universidad de C.
authors.forename: Adrian P
authors.initials: AP
authors.lastname: Mundt
authors.affiliation: Unit of Social and Community Psychiatry (World Health Organization Collaborating Centre for Mental Health Services Development), Queen Mary University of London, London, England.
authors.forename: Winnie S
authors.initials: WS
authors.lastname: Chow
authors.affiliation: Vilardebó Psychiatric Hospital, Montevideo, Uruguay.
authors.forename: Margarita
authors.initials: M
authors.lastname: Arduino
authors.affiliation: Servicios de Salud Mental, Universidad ISALUD, Buenos Aires, Argentina6Hospital de Salud Mental J. A. Esteves, Buenos Aires, Argentina.
authors.forename: Hugo
authors.initials: H
authors.lastname: Barrionuevo
authors.affiliation: Department of Psychiatry and Mental Health, Hospital Clínico Universidad de Chile, Santiago, Chile7Department of Psychiatry, Universidad de los Andes, Santiago, Chile.
authors.forename: Rosemarie
authors.initials: R
authors.lastname: Fritsch
authors.affiliation: Department of Psychiatry, Universidad Nacional de Asunción, San Lorenzo, Paraguay.
authors.forename: Nestor
authors.initials: N
authors.lastname: Girala
authors.affiliation: School of Public Health, Universidad de Chile, Santiago, Chile.
authors.forename: Alberto
authors.initials: A
authors.lastname: Minoletti
authors.affiliation: Psychiatric Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Flávia
authors.initials: F
authors.lastname: Mitkiewicz
authors.affiliation: Department of Psychology, Universidad Privada de Santa Cruz de la Sierra, Santa Cruz de la Sierra, Bolivia.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Rivera
authors.affiliation: Psychiatric Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: María
authors.initials: M
authors.lastname: Tavares
authors.affiliation: Unit of Social and Community Psychiatry (World Health Organization Collaborating Centre for Mental Health Services Development), Queen Mary University of London, London, England.
authors.forename: Stefan
authors.initials: S
authors.lastname: Priebe
mesh_terms: D001118:Argentina / Q000453:epidemiology; D001838:Bolivia / Q000453:epidemiology; D001938:Brazil / Q000453:epidemiology; D002677:Chile / Q000453:epidemiology; D006778:Hospitals, Psychiatric / Q000191:economics / Q000706:statistics & numerical data*; D006801:Humans; D008605:Mental Health Services / Q000331:legislation & jurisprudence / Q000706:statistics & numerical data / Q000639:trends; D010239:Paraguay / Q000453:epidemiology; D011330:Prisons / Q000191:economics / Q000706:statistics & numerical data*; D014583:Uruguay / Q000453:epidemiology