In 1996, a questionnaire was distributed to 4000 Australian commercial pilo
ts for the quantification of symptoms of dry eye. The 1246 respondents rang
ed in age from 18-71 years (mean age 40.4 years), and 98.2% were men. Sympt
oms of dry eye during flight were reported by 901 (72.3%, 95% CI = 69.7-74.
8) while only 67 (5.4%, 95% CI = 4.2-6.8) reported dry eye independent of f
light. In univariate analyses, the following factors were associated with d
ry eye in flight: age, use of distance glasses, smoking, average weekly num
ber of flight hours, type of aircraft usually flown, and normal cruising al
titude. In a multiple logistic regression model, only the class of aeroplan
e (large jets vs propeller-driven planes) (OR = 1.75, 95% CI = 1.34-2.28) a
nd estimated number of flight hours per week (OR = 1.58, 95% CI = 1.34-1.86
) were related to dry eye symptoms. In conclusion, self-reported symptoms o
f dry eye are common in Australian pilots and are associated with aeroplane
class and flying time.