title: Characteristics of herpes zoster-associated hospitalizations in Madrid (SPAIN) before vaccine availability.
abstract: OBJECTIVE
  This study aimed to estimate the frequency of hospitalizations due to herpes zoster (HZ) and to describe their clinical characteristics by sex and age group.
  
  
  METHODS
  Descriptive population-based cross-sectional study of hospital admissions due to HZ from 2003 to 2013 among residents in the Autonomous Community of Madrid. Sex, age, comorbidities, length of stay and outcomes were collected and described. Crude and age-adjusted cumulative incidence rates, and stratified by sex and age, were estimated. Robust Poisson regression analysis was used to calculate the incidence rate ratios by age group.
  
  
  RESULTS
  2039 hospitalizations were identified (51.0% in women). Complicated HZ caused 48.7% of them (50.9% in women). The hospitalization rate was 2.98/100,000 person-years and 7.19/1000 cases of HZ in primary care. Both rates were significantly higher in men, except in the extreme age groups. An immunosuppression-associated comorbidity was identified in 32.8% of the cases and was less common in patients ≥75 years of age. The median length of stay was 6 days, and in-hospital mortality was 1.4%.
  
  
  CONCLUSIONS
  Hospitalization rates due to HZ were higher in men and increased with age. In two out of every three cases, a comorbidity that potentially caused immunosuppression could not be identified. These cases could benefit from vaccination.
authors.affiliation: Subdirectorate for Health Promotion and Prevention, Madrid Regional Health Authority, C/ San Martín de Porres, 6, 28035, Madrid, Spain. Electronic address: maria.estebanv@salud.madrid.org.
authors.forename: María D
authors.initials: MD
authors.lastname: Esteban-Vasallo
authors.affiliation: Subdirectorate for Health Promotion and Prevention, Madrid Regional Health Authority, C/ San Martín de Porres, 6, 28035, Madrid, Spain.
authors.forename: M Felicitas
authors.initials: MF
authors.lastname: Domínguez-Berjón
authors.affiliation: Area of Preventive Medicine and Public Health, Rey Juan Carlos University, Avda. de Atenas, s/n - 28922 Alcorcón, Madrid, Spain.
authors.forename: Ángel
authors.initials: Á
authors.lastname: Gil de Miguel
authors.affiliation: Subdirectorate for Health Promotion and Prevention, Madrid Regional Health Authority, C/ San Martín de Porres, 6, 28035, Madrid, Spain.
authors.forename: Jenaro
authors.initials: J
authors.lastname: Astray-Mochales
authors.affiliation: Subdirectorate for Health Promotion and Prevention, Madrid Regional Health Authority, C/ San Martín de Porres, 6, 28035, Madrid, Spain.
authors.forename: Luis M
authors.initials: LM
authors.lastname: Blanco-Ancos
authors.affiliation: Area of Preventive Medicine and Public Health, Rey Juan Carlos University, Avda. de Atenas, s/n - 28922 Alcorcón, Madrid, Spain.
authors.forename: Ruth
authors.initials: R
authors.lastname: Gil-Prieto
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D002908:Chronic Disease; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D006562:Herpes Zoster / Q000150:complications / Q000453:epidemiology*; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D013030:Spain / Q000453:epidemiology; D055815:Young Adult
keywords: Chronic conditions; Comorbidity; Epidemiology; Herpes zoster; Hospitalization; Immunosuppression; Incidence