title: Incidence of Non-Traumatic Subconjunctival Hemorrhage in a Nationwide Study in Taiwan from 2000 to 2011.
abstract: OBJECTIVE
  To determine the nationwide incidence of non-traumatic subconjunctival hemorrhage (NTSCH) in Taiwan from 2000-2011 and to analyze the risk factors for NTSCH using a case-control analysis.
  
  
  METHODS
  This is a population-based cohort administrative database study. Randomly selected 1,000,000 residents from the Taiwan National Health Insurance Research Database in 2000 and followed for 12 years to determine the population incidence of NTSCH. Individuals with the first diagnosis of subconjunctival hemorrhage were identified by the corresponding International Classification of Diseases code (ICD) 372.72. Traumatic subconjunctival hemorrhages (ICD-9 codes 921, 871, 850-854 and 959.01) were excluded. The association of NTSCH with various demographic factors, comorbidities and use of medications was studied by a population based case-control analysis using data of 2008-2011.
  
  
  RESULTS
  A total of 67,720 patients with a first-time diagnosis of NTSCH were identified during the 12 years period. The mean annual incidence was 65 per 10,000 individuals (crude incidence) and 60 per 10,000 individuals (age- and sex-standardized incidence). The incidence rate of NTSCH was higher in women than in men, [men-women ratio: 0.80 (95% confidence interval: 0.78-0.81)]. The age-specific incidence decreased from childhood to the group of teenagers, after which it increased to a maximal value of 136.2 per 10,000 people in the age group of 60-69 years. Case-control analysis showed that comorbidities of hypertension, purpura and thrombocytopenia, and the use of aspirin were significantly associated with the risk of NTSCH.
  
  
  CONCLUSIONS
  This study indicates that NTSCH is a common eye disease that occurs once in 167 individuals in a general East Asian population per year. It occurs more often in women than in men and the age-specific incidence peaked in the age group of 60-69 years. Hypertension, purpura and thrombocytopenia, and the use of aspirin are the major risk factors for NTSCH.
authors.affiliation: Department of Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, Icahn School of Medicine at Mount Sinai, New York, NY, United States of America; Department of Ophthalmology, Show Chwan Memorial Hospital, Changhua, Taiwan.
authors.forename: Dan-Ning
authors.initials: DN
authors.lastname: Hu
authors.affiliation: Institue of Clinical and Medical Science, China Medical University, Taichung, Taiwan; Management Office for Health Data, China Medical University and Hospital, Taichung, Taiwan.
authors.forename: Chih-Hsin
authors.initials: CH
authors.lastname: Mou
authors.affiliation: Department of Ophthalmology, Show Chwan Memorial Hospital, Changhua, Taiwan; Institute of Electrical and Computer Engineering, National Chiao Tung University, Hsinchu, Taiwan.
authors.forename: Shih-Chun
authors.initials: SC
authors.lastname: Chao
authors.affiliation: Department of Ophthalmology, Show Chwan Memorial Hospital, Changhua, Taiwan.
authors.forename: Ching-Yang
authors.initials: CY
authors.lastname: Lin
authors.affiliation: Department of Ophthalmology, Show Chwan Memorial Hospital, Changhua, Taiwan.
authors.forename: Chan-Wei
authors.initials: CW
authors.lastname: Nien
authors.affiliation: Department of Ophthalmology, Show Chwan Memorial Hospital, Changhua, Taiwan.
authors.forename: Pei-Tzu
authors.initials: PT
authors.lastname: Kuan
authors.affiliation: Department of Ophthalmology, Medical Faculty Mannheim of the Ruprecht-Karls-University, Heidelberg, Germany.
authors.forename: Jost B
authors.initials: JB
authors.lastname: Jonas
authors.affiliation: Institue of Clinical and Medical Science, China Medical University, Taichung, Taiwan; Management Office for Health Data, China Medical University and Hospital, Taichung, Taiwan.
authors.forename: Fung-Chang
authors.initials: FC
authors.lastname: Sung
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001241:Aspirin / Q000009:adverse effects; D002648:Child; D015897:Comorbidity; D003228:Conjunctiva / Q000098:blood supply / Q000473:pathology; D003229:Conjunctival Diseases / Q000139:chemically induced / Q000453:epidemiology* / Q000473:pathology; D005130:Eye Hemorrhage / Q000139:chemically induced / Q000453:epidemiology* / Q000473:pathology; D005260:Female; D006306:Health Surveys; D006801:Humans; D006973:Hypertension / Q000453:epidemiology* / Q000473:pathology; D015994:Incidence; D008297:Male; D008875:Middle Aged; D010975:Platelet Aggregation Inhibitors / Q000009:adverse effects; D011693:Purpura / Q000453:epidemiology* / Q000473:pathology; D012307:Risk Factors; D013624:Taiwan / Q000453:epidemiology; D013921:Thrombocytopenia / Q000453:epidemiology* / Q000473:pathology
chemical_list: D010975:Platelet Aggregation Inhibitors; D001241:Aspirin