Laughter therapy in the management of dry eyes

In a randomised controlled trial (n=299, China)

• laughter exercise was non-inferior to 0.1% sodium hyaluronic acid in relieving subjective symptoms at 8 weeks (mean change ocular surface disease index score:−10.5 vs −8.83 points, respectively, mean difference −1.45, 95% CI−5.08 to 2.19; p=0.43)
  
• participants in the control group applied artificial tears, 0.1% sodium hyaluronic acid eyedrops, to both eyes four times daily for eight weeks
  
• drawing from previously established methods of laughter therapy, researchers adapted and developed the laughter exercise to optimally engage the ocular muscles of participants, who were instructed to perform the exercise four times daily for eight weeks
  • at the baseline visit, a video showed the execution of the exercise
    • specifically, laughter exercise required them to vocalise and repeat the phrases as “Hee hee hee, hah hah hah, cheese cheese cheese, cheek cheek cheek, hah hah hah hah hah hah” 30 rounds each time, lasting for at least five minutes

Reference:

1. Li J, Liao Y, Zhang S, Jin L, Congdon N, Fan Z et al. Effect of laughter exercise versus 0.1% sodium hyaluronic acid on ocular surface discomfort in dry eye disease: non-inferiority randomised controlled trial. BMJ 2024; 386:e080474