title: Incidence of herpes zoster and associated events including stroke--a population-based cohort study.
abstract: BACKGROUND
  More detailed understanding of herpes zoster (HZ) is called for in the context of an increasing observed frequency of disease, and ongoing discussions regarding potential consequences of the disease. Thus, population-based data on incidence and complications of HZ are needed.
  
  
  METHODS
  We conducted a register-based cohort study in Västra Götaland County (population 1.5 million) in Sweden. We collected data on all patients diagnosed with HZ during the years 2008 to 2010 from population-based registers. Incidence rates (IR) of HZ and related complications were calculated and stratified by age and sex.
  
  
  RESULTS
  There were 13 269 new HZ cases during the study period. Overall, the IR of herpes zoster in both genders was 3.25 (95% CI: 3.16-3.34) per 1000 person years in 2010. The incidence was consistently higher in women than in men and in older than in young. A history of immunosuppression was more common than in the general population. The incidence was highest in individuals over 80 years of age (IR 9.2 per 1000 person years, 95% CI: 8.8-9.6) during 2008-2010. The most common complications to HZ were ocular engagement and postherpetic neuralgia; risks for stroke and sepsis were significantly elevated during the one year following diagnosis, especially in the youngest age group of patients 0-39 years.
  
  
  CONCLUSIONS
  Herpes zoster is more common in women, the elderly and immunosuppressed individuals. We verify a population-based association between herpes zoster and risk for stroke and sepsis, which may merit concern.
authors.affiliation: Department of Laboratory Medicine, Karolinska Institutet, S-141 86, Stockholm, Sweden. Karin.sundstrom@ki.se.
authors.forename: Karin
authors.initials: K
authors.lastname: Sundström
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, S-141 86, Stockholm, Sweden. caroline.weibull@ki.se.
authors.forename: Caroline E
authors.initials: CE
authors.lastname: Weibull
authors.affiliation: Division of Clinical Pharmacology, Dept. of Laboratory Medicine, Karolinska Institutet, S-141 86, Stockholm, Sweden. karin.soderberg-lofdal@karolinska.se.
authors.forename: Karin
authors.initials: K
authors.lastname: Söderberg-Löfdal
authors.affiliation: Department of Infectious Diseases, Institute of Biomedicine, University of Gothenburg, S-405 30, Gothenburg, Sweden. tomas.bergstrom@microbio.gu.se.
authors.forename: Tomas
authors.initials: T
authors.lastname: Bergström
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, S-141 86, Stockholm, Sweden. par.sparen@ki.se.
authors.forename: Pär
authors.initials: P
authors.lastname: Sparén
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, S-141 86, Stockholm, Sweden. lisen.arnheim.dahlstrom@ki.se.
authors.forename: Lisen
authors.initials: L
authors.lastname: Arnheim-Dahlström
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006562:Herpes Zoster / Q000150:complications* / Q000191:economics / Q000453:epidemiology*; D014645:Herpesvirus 3, Human / Q000276:immunology; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D051474:Neuralgia, Postherpetic / Q000453:epidemiology / Q000821:virology; D012042:Registries; D018805:Sepsis / Q000453:epidemiology / Q000209:etiology / Q000821:virology; D020521:Stroke / Q000453:epidemiology / Q000821:virology; D013548:Sweden / Q000453:epidemiology; D055815:Young Adult
chemical_list: D007166:Immunosuppressive Agents