title: Epidemiology of acute primary angle-closure glaucoma in the Hong Kong Chinese population: prospective study.
abstract: OBJECTIVE
  To determine the incidence of acute primary angle-closure glaucoma in the Hong Kong Chinese population, and to identify risk factors for this condition.
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  University teaching hospital, Hong Kong.
  
  
  METHODS
  Patients with acute primary angle-closure glaucoma presenting between 1 March 1998 and 29 February 2000.
  
  
  METHODS
  Demographic data, presenting symptoms and signs, temporal details of the presentation, and precipitating factors. The crude regional incidence was calculated according to the Hong Kong population census of 1991 and the age-specific incidence was calculated.
  
  
  RESULTS
  Seventy-two cases (72 eyes of 72 patients) of acute primary angle-closure glaucoma were recruited. The crude incidence was 10.4 per 100,000 per year in the population aged 30 years and older. Patients at higher risk of attacks were those aged 70 years or older (age-specific incidence, 58.7 per 100,000 per year) and females, who had a relative risk of 3.8 compared with males (95% confidence interval, 1.7-8.4). Only four (5.6%) patients had a positive family history of acute primary angle-closure glaucoma. Seventeen (23.6%) patients were noted to have an upper respiratory tract infection before the attack, and 25 (34.7%) patients had taken antitussive agents. There was a statistically significant inverse correlation between the monthly attack rate and the monthly rate of influenza (Spearman's rank correlation coefficient = -0.388; P=0.031).
  
  
  CONCLUSIONS
  There is a high incidence of acute primary angle-closure glaucoma among Chinese residents of Hong Kong, with elderly females at highest risk. A significant proportion of patients reported upper respiratory tract infection or the use of antitussive medication prior to attacks.
authors.affiliation: Department of Ophthalmology, United Christian Hospital, Hip Wo Street, Kwun Tong, Kowloon, Hong Kong.
authors.forename: J S
authors.initials: JS
authors.lastname: Lai
authors.forename: D T
authors.initials: DT
authors.lastname: Liu
authors.forename: C C
authors.initials: CC
authors.lastname: Tham
authors.forename: R T
authors.initials: RT
authors.lastname: Li
authors.forename: D S
authors.initials: DS
authors.lastname: Lam
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D005260:Female; D015812:Glaucoma, Angle-Closure / Q000453:epidemiology*; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies