Comparative study of dry eye syndrome at high altitude and low altitude regions

Abstract

PURPOSE: To study and compare the dry eye syndrome at high altitude (Khaplu Gilgit Baltistan) and low altitude (Lahore Punjab) regions.

METHOD: A cross sectional study has been taken in two groups. The data of group A is taken at height of 2600m (Khaplu Gilgit Baltistan) and the data of group B is taken at low altitude (Lahore Punjab) and compared the dry eye syndrome at high and low altitude regions. One group contains 44 subjects at high altitude and second group also contain 44 subjects at low altitude. In order to collect data the OSDI questionnaire system is used which is a more reliable, authentic tool to find prevalence of dry eye. Scoring system is used to find out end result.

RESULTS: 88 subjects were enrolled in this study. Out of which half of the data i.e. 44 is collected at high altitude region (Khaplu district in Gilgit Baltistan) and the remaining half is taken from low altitude region i.e. from Lahore Punjab. At high altitude region total 44 subjects were enrolled out of which 18 (40.9%) subjects were normal, 9 (20.4%) subjects with mild dry eye syndrome,12 subjects (27.2%) with moderate DES and 5 subjects (11.3%) with severe DES. Similarly, at low altitude (Lahore Pakistan) total 44 subjects were enrolled out of which 30 (68.1%) subjects were normal, 7 (15.9%) subjects with mild dry eye syndrome, 4 subjects (9.0%) with moderate dry eye syndrome and only 3 (6.8%) subjects with severe dry eye syndrome. The incidence of dry eye was found significantly high at high altitude region as compared to low altitude region (Chi-square test, p=0.04). P-value < 0.05, that shows the significant result, so that there is significant difference of DES at high altitude and low altitude regions. There is more risk of occurrence of DES at High altitude.
CONCLUSION: The prevalence of DES at high altitude is significantly higher as compared to low altitude region (p=0.04). Many environmental factors which play role in increasing the incidence of dry eye at high altitude such as high exposure to UV radiation due to height, dry environment, low temperature, low humidity, and wind chill factor.
KEY WORDS: Ocular surface disease index, Khaplu, dry eye syndrome, dry eye