Background  Sleep apnea hypopnea syndrome (SAHS) is a common sleep disorder associated with a variety of eye diseases. In recent years, researchers have gradually paid attention to the relationship between SAHS and dry eye syndrome.

  Objective  To evaluate the changes of tear film function in patients with SAHS by Keratograph 5M ocular surface comprehensive analyzer.

  Methods  Forty patients who were diagnosed with OSAHS initially and 30 healthy volunteers were enrolled. Sleep monitoring and Keratograph 5M ocular surface comprehensive analysis were performed respectively.

  Results  Compared with the control group, the first tear breakup time, average tear breakup time and central tear river height decreased in the SAHS group, while the scores of loss degree of upper and lower meibomian glands increased, but the differences were not statistically significant (P>0.05). With the increase of obstruction severity, there was obvious absence of meibomian gland (P<0.05). With the increasing degree of hypoxia, the time of tear film rupture was shortened and the meibomian gland loss increased (P<0.05). Conclusion Keratograph 5M ocular surface comprehensive analyzer can objectively and intuitively evaluate the tear film status of SAHS patients. The more severe obstruction and hypoxia is, the more meibomian gland integrity is destroyed, resulting in the decline of tear film function.