title: Hepatitis B virus infection among inpatients of a psychiatric hospital of Mexico.
abstract: BACKGROUND
  The epidemiology of the hepatitis B virus (HBV) infection in psychiatric patients from developing countries is poorly studied. Therefore, we sought to determine the frequency of HBV surface antigen (HBsAg) and HBV surface antibody (HBsAb) serological markers of HBV infection in a population of patients of a psychiatric hospital in Durango City, Durango, Mexico, and to determine whether there are any epidemiological characteristics of the subjects associated with the infection.
  
  
  METHODS
  Out of 150 patients of the psychiatric hospital of Durango City, 99 were examined for HBsAg and HBsAb by AUSZYME MONOCLONAL (Abbott Laboratories, Abbott Park, IL, USA) assay and AUSAB (Abbott Laboratories, Abbott Park, IL, USA) assay, respectively. Epidemiological data from each participant was also obtained. For comparison purposes, 2505 blood donors were examined for HBsAg seropositivity.
  
  
  RESULTS
  Out of the 99 patients studied, twelve showed serological evidence of HBV infection (12.1%); 7 of them (7.1%) were positive for HBsAg, and 5 (5.1%) were positive for HBsAb. Out of the 2505 blood donors, 2 (0.0008%) were HBsAg positive. Seropositivity to HBV markers was associated with an age of 45 years and older (OR = 4.27; 95%CI = 1.02-18.78). Other characteristics as gender, number of hospitalizations, duration of the last hospitalization, and clinical diagnosis were not associated with seropositivity to HBV infection markers. Patients showed a significantly higher HBsAg seropositivity than blood donors (p < 0.0000001).
  
  
  CONCLUSIONS
  HBV was found to be an important infectious agent in the Mexican psychiatric inpatient population studied. Health care strategies for prevention and control of HBV infection in psychiatric hospitals should pay special attention to patients aged forty-five years and older.
authors.affiliation: Facultad de Medicina, Universidad Juárez del Estado de Durango, Durango, Mexico. alvaradocosme@yahoo.com
authors.forename: Cosme
authors.initials: C
authors.lastname: Alvarado Esquivel
authors.forename: Miguel Angel
authors.initials: MA
authors.lastname: Arreola Valenzuela
authors.forename: Miguel Francisco
authors.initials: MF
authors.lastname: Mercado Suárez
authors.forename: Francisco
authors.initials: F
authors.lastname: Espinoza Andrade