Study: Topical insulin for dry eye in diabetics. But why?
Before reading this abstract, I glanced through a news report that came up in my Google feed, suggesting that this freshly published study indicated topical insulin may be a good dry eye treatment for diabetics.
Then I read the abstract, and thought, what the !@#$?
According to the abstract, this randomized double-blind study compared use of topical insulin and artificial tears four times daily in diabetics with dry eye and found:
BOTH improved symptoms (OSDI scores)
BOTH made clinical signs WORSE (Schirmer, TBUT)
Apparently the study authors, in the study itself, recommended considering topical insulin dissolved in normal saline as an artificial tear substitute for cost management purposes, which makes sense, and I’m all for practical ways to manage symptoms.
But… how is it that WORSENING clinical signs isn’t raising a red flag here?
By the way, I’d really, really like to know what “standard artificial tears” are. CMC? PEG? Or HA, which is standard outside the US and, unlike the others, actually works pretty well?
Short-Term Results of Trial of Topical Insulin for Treatment of Dry Eyes in Diabetics. Aniah et al, Eye Contact Lens. 2019 May 22.
To assess the short-term effects of topical insulin (TI) 1 unit/drop 4 times per day for 4 weeks on the symptoms and signs of diabetic with dry eye disease (DED).
In this randomized, double-blind interventional study, diabetics with DED aged 18 to 60 years were randomly assigned to TI or standard artificial tears (SAT). Baseline Ocular Surface Disease Index (OSDI), Schirmer I test (ST), tear break-up time (TBUT), and ocular Sjögren's International Collaborative Clinical Alliance (SICCA) score were compared 4 weeks after treatment.
A total of 160 participants (involving 320 eyes) received either TI (n=80) or SAT (n=80). After 4 weeks of treatment, a significant number of participants in both TI and SAT groups showed improvement in their OSDI score, 66% and 63%, respectively (P=0.0001), but were not significantly better than each other (P=0.453). However, most participants in both groups showed worsening of ST and TBUT (P>0.05). Most of the participants in both groups showed no change in their ocular SICCA score (P>0.05).
The study has shown a significant and similar improvement in the OSDI score for TI 1 unit/drop four times daily and SAT in treating diabetics with DED. Further research is required to understand the long-term effects of TI on the ocular surface