Effects of Aerobic Exercise on Tear Secretion and Tear Film Stability in Dry Eye Patients

Abstract Background: To study the effects of aerobic exercise (AE) on tear secretion and tear film stability in dry eye patients.Methods: Firstly we observed Schirmer Ⅰ test and 6 tear compositions detected by ELISA in 34 eyes of dry eye patients and 34 eyes of normal subjects before and after AE. Then we observed 30 eyes of dry eye patients and 30 eyes of normal subjects before and after AE, the evaluated variables included tear meniscus height (TMH), first and average non-invasive tear breakup time (F-NITBUT and A-NITBUT), lipid layer thickness (LLT), number of incomplete and complete blinks, partial blink rate (PBR) and visual acuity.Results: In dry eye group, compared with baseline, Schirmer Ⅰ test at 0 minutes after AE increased significantly (P < 0.001), F-NITBUT and A-NITBUT at every time point after AE prolonged significantly (P < 0.001, P = 0.007, P = 0.036; P < 0.001, P = 0.001, P = 0.044), number of incomplete blinks and PBR at 10 minutes after AE decreased significantly (P < 0.001; P < 0.001) while number of complete blinks increased significantly (P < 0.001), visual acuity at 10 and 20 minutes after AE improved significantly (P = 0.017, P = 0.021). The overall oxidative stress marker 8-hydroxy-2’-deoxyguanosine at 0 minutes after AE decreased significantly compared with baseline (P = 0.040).Conclusion: AE promotes tear secretion and improves tear film stability in dry eye patients. AE may be a potential treatment for dry eye.Trial registration: Chinese Clinical Trial Registry, ChiCTR2000038673. Registered 27 September 2020, http://www.chictr.org.cn/showproj.aspx?proj=57282