ABSTRACT
Dry eye symptoms are associated with refractive errors. We aimed to measure the tear evaporation rate (TER) in subjects with refractive errors (RE) using a portable evaporimeter. This nonrandomized, case-control, and observational study included 75 subjects, including 25 subjects aged 18-38 years (28.8 ± 6.8 years) with myopia (-0.75 to -3.75 D) and 25 subjects aged 18-39 years (27.7 ± 5.5 years) with hyperopia (+0.50 to +3.75 D). In addition, a control group of 25 subjects with emmetropic eyes aged 20-30 years (23.6 ± 2.6 years) was recruited. The ocular surface disease index (OSDI) was completed, followed by the TER measurements using a portable evaporimeter. The OSDI score and TER measurements showed dry eye symptoms in 36% and 48% of myopic subjects, respectively. For hyperopic participants, dry eye was observed in 24% and 56% of the subjects based on the OSDI and TER scores, respectively. Significant differences (Mann-Whitney U test; p < 0.001) were found among the OSDI and TER scores recorded within the study (myopic and hyperopic subjects) and control groups. Significant strong positive correlations were detected between the OSDI and TER scores in both myopic (p = 0.004; r = 0.559) and hyperopic (p = 0.001; r = 0.619) subjects. The TER scores were significantly higher in subjects with RE (myopic and hyperopic) as compared with individuals with normal eyes.
ABSTRACT
Diabetes is a very common disease and is considered a risk factor for many diseases such as dry eye. The aim of the current work was to evaluate the tear evaporation rate (TER) in patients with diabetes using a hand-held evaporimeter. This observational, case-control and non-randomized study included 30 male patients with diabetes (17 controlled and 13 uncontrolled) with a mean ± standard deviation (SD) of 33.1 ± 7.9 years. An age-matched (18-43 years; 32.2 ± 6.5 years) control group consisting of 30 male subjects was also enrolled for comparison. Subjects with thyroid gland disorder, a high body mass index, high blood cholesterol, or thalassemia, contact lens wearers, and smokers were excluded. The TER was measured after the completion of the ocular surface disease index (OSDI) by each participant. The OSDI and TER median scores were significantly (Wilcoxon test, p < 0.05) higher in patients with diabetes (median (interquartile range; IQR) = 12.0 (8.3) and 46.4 (36.7) g/m2h, respectively) compared to the subjects within the control group (5.6 (7.0) and 15.1 (11.9) g/m2h, respectively). The median scores for the OSDI and TER measurements were significantly (Wilcoxon test, p < 0.05) higher among uncontrolled diabetes patients (13.0 (11.5) and 53.4 (14.2) g/m2h, respectively) compared to those obtained for patients with controlled diabetes (11.0 (8.0) and 27.3 (32.6) g/m2h, respectively). The tear evaporation rate in patients with diabetes was significantly higher compared to those obtained in subjects without diabetes. Uncontrolled diabetes patients have a higher tear evaporation rate compared to controlled diabetes patients. Therefore, diabetes can lead to eye dryness, since these patients possibly suffer excessive tear evaporation.
