DES can lead to various consequences, some of which are potentially dangerous.
The most common consequence of dry eye syndrome is patients giving up on using contact lenses and switching back to glasses. The unpleasant symptoms discourage contact lens users from wearing them and unless they are really set on the use of contact lenses, they often don't seek professional help and simply go back to using spectacles. This situation could be avoided with proper education provided by the eye care practitioner during the first contact lens fitting session.
Another consequence of DES, is decreased work productivity. Research shows that people with dry eye syndrome often engage in presenteeism (they come to work, but their productivity is significantly affected by their condition) and that there is a great difference between patients with dry eye and healthy individuals in terms of work productivity. What is more, this has a serious impact on the financial situation of their employers, as the yearly cost of productivity lost due to dry eye syndrome is approximately $740 per person. In addition, the costs of dry eye treatment are lower than the costs of decreased productivity, so effective diagnosis and treatment is economically beneficial.
Several studies showed that functional visual acuity (representing the quality of vision that patients experience when doing their everyday tasks, e.g. driving a car or reading a book) is significantly worse in dry eye patients, even though visual acuity measured during an optometrists exam may seem very good. One study measured driving performance among healthy individuals and those affected by DES and the results showed that dry eye patients had significantly worse vision while driving than healthy participants, especially regarding such situations as roundabout or crossroad approaches. In addition, dry eye patients reacted to changes on the road more slowly.