Therapeutic effects of acupuncture in typical dry eye: a systematic review and meta-analysis

Acupuncture is a treatment option for dry eye syndrome (DES), but its efficacy remains still controversial. We assessed the effectiveness of this treatment for typical DES without specific aetiologies. Eight databases up through June 2018 were searched for randomized clinical trials (RCTs) comparing treatments of acupuncture with artificial tears. The risk of bias was assessed using Cochrane criteria, and a random effects model was used for meta-analyses on tear-film breakup time (BUT), Schirmer test, corneal fluorescein staining (CFS), ocular surface disease index, visual analogue scale and score of symptoms (SOS). Subgroup and sensitivity analyses were conducted to explore the heterogeneity, and publication bias was assessed by funnel plot using Egger's test. Twenty-one RCTs in 19 studies (n = 1542 eyes) met our eligible criteria. The results demonstrated the superiority of acupuncture in improving the symptoms of BUT, Schirmer test, CFS and SOS, compared to artificial tears acting alone. The BUT and Schirmer test were also more improved in acupuncture combination with artificial tears than artificial tears alone. Further subgroup analyses suggest that acupuncture applied at 2.0-3.0 times per week for 21-30 days may be optimal for treating typical DES. This provides useful information for guiding acupuncture in the clinical trials.