Survey of cataract rate and surgical coverage in agricultural and pastoral area of Chifeng Keshenketeng in Inner Mongolia

Abstract

Background Cataract is a leading blinding eye disease,and the prevalence of cataract varies in different regions. Objective The present study was to investigate the incidence of cataract,surgical coverage rate of cataract and postoperative visual acuity,and to propose a strategy for blindness prevention in Chifeng Keshiketengqi. Methods This is a cross-sectional survey of research.A random cluster sampling method was performed in 12 populated areas in Keshiketengqi.Inhabitants over 50 years in the region were included in this survey.This study was approved by the Ethic Committee of Inner Mongolia People' s Hospital.Informed consents were obtained orally from all the subjects.Disease history,visual acuity,intraocular pressure and regular ophthamological examinations were performed.The inclusion criteria of a pilot study and detailed protocol were employed to calculate the incidence rate of cataract.The questionnaire survey was simultaneously adopted to analyze the cataract-related factors.The surgical coverage rate of cataract in this area was calculated. Results In a total 4234 inhabitants,3826 subjects participated in the survey with a response rate of 90.36％.Cataract was found in 1200 participants with an incidence rate of 31.39％.Age,the female gender and illiteracy were identified as risk factors for cataract (x2 =101.005,P =0.000 ;x2 =58.853,P =0.000 ;x2 =12.037,P =0.007 ).The prevalence rates of cataract were 36.98％ and 33.56％ for illiterates and women,respectively.The incidence rate in the Mongol population was significantly higher than that of the Han population ( 34.83％ vs.29.76％ ) (x2 =9.734,P =0.001 ).The cataract surgery rate increased yearly since 1998.When the vision acuity of the fellow eye was ＜0.1,the surgery coverage rate was 20.60％,but the rates were lower in female,illiterates and the Mongol population (x2 =1.993,P =0.038 ;x2 =16.463,P =0.044 ;x2 =8.523,P =0.029).When a pinhole visual acuity of ＜0.05 was determined as the criteria of blindness,the surgical coverage rate was 28.36％.The cataract surgical coverage rates for Han and Mongolian were 30.67％ and 24.53％,respectively,with a significant difference between them (x2 =12.951,P=0.000).The social burden rate was 3.34％ in this area,with a majority of females,illiterates and the Mongol population ( P＜0.05 ).Conclusions In agricultural and pastoral areas of Chifeng Keshiketengqi,the ≥50 years old population has a high rate of cataract blindness and low surgery coverage rate.Surgery is still the preferred way for cataract treatment. Key words: Cataract; Blindness prevention; Prevalence; Epidemiology; National minority