Study: Incomplete blinking doubles dry eye risk
According to this study, people with an incomplete blink:
Tended to have dry eye according to TFOS DEWS II diagnostic criteria
Had higher OSDI scores
Had increased meibomian gland dropout
Had poorer lipid layer thickness and tear film stability
Ocul Surf. 2018 Jun 5. pii: S1542-0124(18)30026-0. doi: 10.1016/j.jtos.2018.06.001.
Wang MTM, Tien L, Han A, Lee JM, Kim D, Markoulli M, Craig JP.
To investigate the influence of blinking on tear film parameters, ocular surface characteristics, and dry eye symptomology.
A total of 154 participants were recruited in an age, gender and ethnicity-matched cross-sectional study, of which 77 exhibited clinically detectable incomplete blinking, and 77 did not. Blink rate, dry eye symptomology, tear film parameters, and ocular surface characteristics were assessed in a single clinical session.
Overall, a higher proportion of participants exhibiting incomplete blinking fulfilled the TFOS DEWS II dry eye diagnostic criteria (64% versus 44%, p = 0.02), with an odds ratio (95% CI) of 2.2 (1.2-4.2) times. Participants exhibiting incomplete blinking had higher Ocular Surface Disease Index scores (18 ± 13 versus 12 ± 9, p = 0.01), and greater levels of meibomian gland dropout (41.3 ± 15.7% versus 27.5 ± 14.1%, p < 0.001). Furthermore, poorer tear film lipid layer thickness, non-invasive tear film stability, expressed meibum quality, eyelid notching, and anterior blepharitis grades were also observed in those exhibiting incomplete blinking (all p < 0.05). Blink rate did not correlate significantly with any ocular surface parameters (all p > 0.05).
Incomplete blinking was associated with a two-fold increased risk of dry eye disease. The greater levels of meibomian gland dropout, as well as poorer expressed meibum quality and tear film lipid layer thickness, observed would suggest that incomplete blinking may predispose towards the development of evaporative dry eye.