title: [Prevalence of cataract in 35-64 years old Kaunas city population].
abstract: The aim of the study was to determine the prevalence of lens opacity among 35-64 years old Kaunas population as well as to evaluate the stage and type of age-related cataract and its distribution in the groups of age and gender.
  
  
  METHODS
  The material of our study was Kaunas city population aged 35 to 64 years who participated in the scientific Monitoring of Trends and Determinants in Cardiovascular Disease (MONICA-4) study during 2001-2002 in the Laboratory of Population Researches, Institute of Cardiology of Kaunas University of Medicine. During this study random sampling method was used for grouping of 1354 persons according to the age and gender (596 males and 759 females). A total of 2708 lens were examined using the Lens Opacity Classification System (LOCS III) after dilatation of pupils. All the investigated persons were divided into decade age groups: 35-44, 45-54 and 55-64 years. All of them were divided into two groups: with cataract and without. Those who had cataract were divided into three groups according to the three stages of disease. All lenses were divided into seven groups: clear lens, posterior subcapsular, nuclear, cortical and mixed cataract, aphakia and pseudophakia.
  
  
  RESULTS
  The lens opacities were present in 106 (17.8%) males and 141 (18.6%) females. The lens opacities of both eyes were observed in 91.3% of investigated persons. In all groups with cataract, the 1st stage comprised 71.6%, 2nd--22.5% and 3rd--6.0% of cases. The prevalence of cataract in decade aged groups according to the stages, respectively in men and women was: among 35-44 years old--1st stage cataract 4.0% and 3.5%, 2nd--unidentified in both groups, 3rd stage--1.0% and unidentified; 45-54 years old--1st stage 9.7% and 9.7%, 2nd--1.0% and 1.1%, 3rd--1.5% and 0.4%; among aged of 55-64 years--the 1st stage as 23.8% and 26.0%, 2nd--9.9% and 11.8%, 3rd--2.0% and 1.5%. In both groups the nuclear cataract dominated (68.2%); in male group--72.4% and female--65.0%. Mixed type comprised 18.3% of cases, respectively 17.9% in males and 18.6% in females, cortical--10.7%, respectively--7.7% and 12.9%; posterior subcapsular--2.8%, respectively--2.8% and 3.4%.
  
  
  CONCLUSIONS
  The lens opacities were found in 17.8% of males and 18.6% of females among investigated 35-64 years old population of Kaunas city. In the groups of both genders domination of nuclear cataract and the 1st stage of all forms of cataract was observed. The incidence of cataract increases significantly with age.
authors.affiliation: Institute for Biomedical Research, Kaunas University of Medicine, Eiveniu 4, 50009 Kaunas, Lithuania. florentinaboj@yahoo.com
authors.forename: Florentina
authors.initials: F
authors.lastname: Bojarskiene
authors.forename: Alvydas
authors.initials: A
authors.lastname: Paunksnis
mesh_terms: D000328:Adult; D000367:Age Factors; D002386:Cataract / Q000145:classification / Q000175:diagnosis / Q000453:epidemiology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D015994:Incidence; D008097:Lithuania / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012737:Sex Factors