Randomized comparison of lipid-containing and non-lipid-containing artificial tears on tear film dynamics over a 3-month period.

PURPOSE: To study the effects of a lipid-containing artificial tear (AT) and a non-lipid-containing AT on tear film dynamics over a 3-month period.

METHODS

Subjects with low lipid layer thickness were randomized to lipid-containing or non-lipid-containing ATs for 3 months. At each visit Ocular Surface Disease Index (OSDI), LipiView, non-invasive and fluorescein tear breakup times, tear lipid layer and aqueous film recordings with EasyTear View+, and corneal staining assessment were performed. Lipid layer thickness and tear thinning rate were calculated using custom LabView programs. Mixed effects models were used to analyze relationships among variables.

RESULTS

Thirty nine subjects completed the study. Mean EasyTear View+ lipid layer thickness with non-lipid-containing AT decreased from baseline (65.1 [61.0, 69.2] nm) to 3 months (58.0 [53.4, 62.7] nm, p = 0.012), whereas mean lipid layer thickness with the lipid-containing AT remained stable (baseline = 59.0 [53.6, 64.4] nm, 3 months = 62.4 [56.1, 68.7] nm, p = 0.30). There was a significant difference in lipid layer thickness change from baseline to 3 months between the lipid-containing (3.4 nm) and non-lipid-containing ATs (-7.1 nm, p = 0.014). Tear thinning rate with the non-lipid-containing AT was faster at 3 months (baseline = 3.01 [2.21, 3.81]%/sec, 3 months = 4.78 [3.62, 5.94]%/sec, p = 0.008), but remained stable with the lipid-containing AT (baseline = 2.84 [1.93, 3.76]%/sec, 3 months = 2.93 [2.15, 3.70]%/sec, p = 0.84). The increase in tear thinning rate from baseline was greater with the non-lipid-containing (1.77%/sec) than the lipid-containing AT (0.09%/sec, p = 0.019). Fluorescein tear breakup time with the non-lipid-containing AT remained stable at 3 months (4.70 [4.14, 5.25] sec) versus baseline (4.23 [3.48, 4.99] sec, p = 0.26), whereas fluorescein tear breakup time with the lipid-containing AT was longer at 3 months (6.33 [4.85, 7.82] sec) versus baseline (4.44 [3.66, 5.22] sec, p = 0.029). There were no significant changes in OSDI score, LipiView lipid layer thickness, non-invasive tear breakup time or corneal staining grade over the 3-month period.

CONCLUSIONS

Patients with lipid deficiency may benefit from lipid-containing AT over the non-lipid-containing AT to stabilize tear lipid thickness and minimize tear thinning while increasing tear breakup time.

TRIAL REGISTRATION: This study was registered at ClinicalTrials.gov (#NCT05705518) on the date of January 20, 2023.