Abstract
Purpose:
Climate change can lead to an increase in levels and allergenicity of environmental pollen, posing a risk of increase in allergies. We measured the frequency and severity of ocular symptoms and their association with pollen levels across seasons.
Methods:
632 university students and staff in Sydney were invited to complete a self-administered online survey. Eye Allergy Patient Impact Questionnaire (EAPIQ) and Aston University Allergy Questionnaire (AUAQ) were completed in 2012 (spring1) and 2013 (autumn, winter and spring2). Burkard volumetric trap was used for daily grass, weed, tree and total pollen counts. Frequency, troublesomeness, severity of ocular symptoms (dryness, itchiness, need to rub, burning, stinging, redness, watering, swelling/puffiness) and AUAQ symptom severity score (0-21) were compared within (one way ANOVA) and between seasons (repeated measures ANOVA). Bonferroni corrected posthoc analysis was used. Associations between pollen counts and symptoms were examined using Spearman Correlation.
Results:
53 subjects completed all phases (age: 28±11 yrs, range 19-63). Tree, weed and total pollen counts were higher in spring (37±20, 8±4, 61±26 n/m3 respectively) than in other seasons (12±16, 2±2, 19±24 n/m3 respectively) (p<0.05). Grass pollen levels remained constant in spring and autumn (13±7 n/m3) but decreased to 0 in winter (p<0.001). Severity and troublesomeness of dry eyes were higher in spring2 than in autumn (p<0.03). Severity of burning eyes and red eyes were higher in spring2 than in autumn (p<0.01). Symptom severity score was higher in spring2 than in autumn or spring1 (p<0.01). Dry eyes (61-74%) and itchy/burning eyes (50-59%) were reported as the most frequent symptoms in all phases. Frequency and troublesomeness of dry eyes were higher than that of red eyes, watery eyes or swollen/puffy eyes in all seasons (p<0.05). Symptom severity score was correlated with grass (ρ=0.32;p=0.005), weed (ρ=0.35;p=0.002), tree (ρ=0.35;p=0.002) and total (ρ=0.33;p=0.03) pollen count during autumn and only weed pollen count (ρ=0.3;p=0.01) during winter.
Conclusions:
Mild ocular symptoms are frequent in Sydney throughout the year and their severity was higher in spring than in autumn. Further analyses including climatic variables and subject behaviour are required in order to understand the relationship between symptoms and pollen counts.
Keywords: 475 conjunctivitis •
421 anterior segment •
459 clinical (human) or epidemiologic studies: biostatistics/epidemiology methodology