Abstract
Purpose: :
(1) to perform a cross-sectional study to evaluate the prevalence of dry eye disease (DED) symptoms in a population-representative cohort of British women from the Twins UK cohort, (2) to examine if there is any association of DED symptoms with (a) tear osmolarity and (b) pain sensitivity.
Methods: :
To date, 311 female subjects from the UK general population were questioned about use of ocular lubricants. Dry eyes symptoms were evaluated using the ocular surface disease index (OSDI) and the short questionnaire dry eyes syndrome (SQ DES). Tear osmolarity of both eyes was measured with the TearLabTM Osmolarity System (San Diego, CA). Temperature pain threshold level was measured. The prevalence of DED was evaluated using recommended thresholds. DED symptoms against clinical outcomes were evaluated using logistic regression and Spearman's rank correlation.
Results: :
Median age (25th, 75th percentile) of this population sample was 50 (40, 61) years. 9.0% [95% CI 5.8-12.2%] used ocular lubricants. Prevalence of DED in this sample was 12.3% [95% CI 8.6-15.9] using SQ DES criteria, 20.3% [95% CI 15.8-24.8%] using OSDI criteria (threshold 15), and 38.0% [95% CI 33.3-42.7%] based on tear osmolarity (threshold 316 mOsms/L for highest score among both eyes). Prevalence reduced to 23.2% [95% CI 15.1-31.2%] using an osmolarity threshold value of 322 mOsml/l. Logistic regression showed an OR of 2.62 (p=0.002) and 2.19 (p=0.009) for having DED diagnosis using OSDI criteria, when having a tear osmolarity above 322 and 316, respectively. Correlation of osmolarity with OSDI score was low (r=0.13, p=0.02). No association between pain threshold level and OSDI symptoms score was found (r=-0.05, p=0.52).
Conclusions: :
Prevalence of DED in the general population is highly dependent on the test used, ranging from 9.0 to 38.0% in this sample of middle-aged women. Our results show that in a general population high tear osmolarity is a moderate predictor of having dry eyes symptoms. Our results do not support the hypothesis that subjects with dry eye disease symptoms have lower pain sensitivity thresholds than those without symptoms.
Keywords: clinical (human) or epidemiologic studies: prevalence/incidence • cornea: tears/tear film/dry eye