Bacteria: the eyelid and eyelashes harbor bacteria, biofilm and sometimes, demodex mites. These factors release toxins onto the lid margin that mix with the tear film and create irritation.
Lid function: if eyelids do not fully seal at night, there can be areas of exposure that cause dry eye symptoms. In addition, if eyelids don’t fully touch during a blink (incomplete blink), the tear film will be unstable.
Environmental: The blink rate drop by at least 50% when doing near activities (reading, working on screens, looking at a phone, etc). Lighting and air quality will also impact comfort.
Systemic disease: underlying systemic conditions (especially inflammatory or autoimmune diseases) increase overall inflammation in the body and ocular surface. Lack of sleep and poor diet are also risk factors.
Corneal compromise: Anything that could cause corneal changes (ie previous contact lens wear, LASIK or refractive surgery, cataract surgery) can increase dry eye symptoms.
Underlying systemic conditions (especially inflammatory or autoimmune conditions)
Certain OTC or prescription medications
Environmental conditions (windy, dry, dusty)
Occupational conditions (increased screen use)
Previous or current contact lens wear
Surgeries like LASIK or cataract surgery