title: Increased risk of intracerebral hemorrhage among patients with chronic osteomyelitis.
abstract: OBJECTIVE
  Inflammation may provoke cerebral arteriolar ectasia, inducing microaneurysm formation and further promoting intracerebral hemorrhage (ICH). Chronic osteomyelitis (COM) is an inflammatory disorder for which study of its role in ICH is lacking. This study explored whether COM increases the risk of ICH.
  
  
  METHODS
  From Taiwan national insurance inpatient claims, 22,052 patients who were newly diagnosed with COM between 1997 and 2010 were identified; 88, 207 age and sex frequency-matched subjects without COM were selected at random for comparison. Risks of ICH associated with COM and comorbidities, including hypertension, diabetes, hyperlipidemia, chronic kidney disease, and drug abuse, were assessed by the end of 2010.
  
  
  RESULTS
  The incidence of ICH was 1.68 times higher in the COM cohort than in the comparison cohort, with an adjusted hazard ratio (HR) of 1.50 (95% CI 1.29-1.74) estimated in the multivariable Cox model. Age-specific analysis showed that the HR of ICH for COM patients decreased with age, with an adjusted HR of 3.28 (95% CI 1.88-5.75) in the < 40-year age group, which declined to 1.11 (95% CI 0.88-1.40) in the elderly. The incidence of ICH increased with the severity of COM; for those with severe COM the adjusted HR was 4.42 (95% CI 3.31-5.89). For subjects without comorbidities, the incidence of ICH was 1.20-fold (95% CI 1.00-1.45) higher in the COM cohort than in the comparison cohort.
  
  
  CONCLUSIONS
  This study suggests for the first time that COM is an inflammatory factor associated with increased risk of ICH, especially in younger patients.
authors.affiliation: Department of Neurology and.|School of Medicine and.
authors.forename: Chun-Hung
authors.initials: CH
authors.lastname: Tseng
authors.affiliation: Department of Neurology and.|School of Medicine and.
authors.forename: Wei-Shih
authors.initials: WS
authors.lastname: Huang
authors.affiliation: Management Office for Health Data, China Medical University Hospital, Taichung;
authors.forename: Chih-Hsin
authors.initials: CH
authors.lastname: Muo
authors.affiliation: Department of Health Promotion and Health Education, National Taiwan Normal University, Taipei, Taiwan.
authors.forename: Yen-Jung
authors.initials: YJ
authors.lastname: Chang
authors.affiliation: Institute of Clinical Medical Science, China Medical University College of Medicine, Taichung; and.
authors.forename: Fung-Chang
authors.initials: FC
authors.lastname: Sung
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D016022:Case-Control Studies; D002543:Cerebral Hemorrhage / Q000453:epidemiology*; D002908:Chronic Disease; D016208:Databases, Factual; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009313:National Health Programs; D010019:Osteomyelitis / Q000150:complications*; D012307:Risk Factors; D013624:Taiwan / Q000453:epidemiology
keywords: CKD = chronic kidney disease; COM = chronic osteomyelitis; HR = hazard ratio; ICH = intracerebral hemorrhage; IR = incidence rate; IRR = incidence rate ratio; NHI = National Health Insurance; RA= rheumatoid arthritis; SLE = systemic lupus erythematosus; VZV = varicella-zoster virus; chronic infection; chronic osteomyelitis; inflammatory disease; intracerebral hemorrhage; vascular disorders