RESUMO
To detect mechanisms of tear-film adaptation to a dry climate, we investigated co-workers in our hospital with air-conditioned rooms. Three groups were formed according to the time of occupancy (6 months to 2 years, 2-4 years, and 4-6 years) and were compared with a control group. The number of patients with frequent dry-eye complaints increased up to 48%, reaching a steady state after 2-4 years. The breakup time was slightly reduced (decrease, 17.5%; P < 0.01) and also reached a steady state after 2-4 years. The tear-ferning test, however, showed a highly significant improvement (P < 0.01). A slight reduction in the Schirmer test was found. Our study indicates that improved tear quality is important for adaptation to long-standing increased evaporation of the tear film.
