title: Increased hospitalizations among sarcoidosis patients from 1998 to 2008: a population-based cohort study.
abstract: BACKGROUND
  Diagnostic and treatment approaches for sarcoidosis have changed dramatically over the past decade. Yet, the most recent reports of trends in hospitalizations of sarcoidosis patients are over ten years old. The objectives of this study were to determine the incidence of sarcoidosis among hospitalized patients and to analyze recent trends and seasonality of hospitalizations in sarcoidosis patients.
  
  
  METHODS
  We performed a retrospective cohort study of the Nationwide Inpatient Sample from 1998 through 2008. We identified all hospitalizations with a primary or secondary diagnosis of sarcoidosis (ICD-9-CM code 135). Incidence was modeled as a seasonal time series about a linear trend.
  
  
  RESULTS
  Time series analysis of the monthly number of hospitalizations revealed a distinct positive linear trend. Over the study period, the number of hospitalized patients with sarcoidosis increased from 37,516 to 70,947 cases. Trends were most pronounced in patients older than 55 years (p < 0.0001), African Americans (p < 0.0001), females (p = 0.0289), and non-Medicaid populations (p < 0.0001). Hospitalizations are seasonal with highest incidence in January through March.
  
  
  CONCLUSIONS
  Hospitalizations among sarcoidosis patients have almost doubled during the past decade, with disproportionate rate increases in African Americans, women, and older patients. The rate also increases among patients with insurance other than Medicaid. This study indicates the need for heightened surveillance of sarcoidosis patients given the unknown consequences of evolving treatment approaches. Our results point to a need for research investigating risk factors for hospitalization, including medications, co-morbidities, demographics, and socioeconomic status.
authors.affiliation: Department of Internal Medicine, University of Iowa, 200 Hawkins Drive, Iowa City, IA 52242, USA. alicia-gerke@uiowa.edu
authors.forename: Alicia K
authors.initials: AK
authors.lastname: Gerke
authors.forename: Ming
authors.initials: M
authors.lastname: Yang
authors.forename: Fan
authors.initials: F
authors.lastname: Tang
authors.forename: Joseph E
authors.initials: JE
authors.lastname: Cavanaugh
authors.forename: Philip M
authors.initials: PM
authors.lastname: Polgreen
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D017281:Cost of Illness; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data / Q000639:trends*; D006801:Humans; D015994:Incidence; D038801:International Classification of Diseases; D016015:Logistic Models; D008297:Male; D008484:Medicaid / Q000706:statistics & numerical data*; D008875:Middle Aged; D012189:Retrospective Studies; D012507:Sarcoidosis / Q000453:epidemiology* / Q000208:ethnology; D012621:Seasons; D017678:Sex Distribution; D014481:United States / Q000453:epidemiology