Abstract: From preserved tears to preservative free hyaluronate tears
Always hard to pass up a study on preservatives in eyedrops, but… the utility of this particular study escapes me entirely.
Hasn’t this been amply proven? Don’t we all know by now that preservatives, on dry eyes especially, are Bad Things?
What is the point of comparing preserved vs unpreserved if the active ingredients are also different? How do you know to what extent the improvement is attributable to the absence of preservative versus the presence of a superior lubricating substance?
Clin Ophthalmol. 2018 Aug 23;12:1519-1525. doi: 10.2147/OPTH.S160053. eCollection 2018.
Nasser L, Rozycka M, Gomez Rendon G, Navas A.
Dry eye disease (DED) is a chronic, multifactorial disease of the ocular surface leading to discomfort, visual disturbance, and tear film instability, with potential damage to the ocular surface.
The aim of this study was to assess the clinical benefit of a switch from preserved to preservative-free artificial tears (ATs) containing hyaluronate in patients with DED.
MATERIALS AND METHODS:
This is a nationwide, multicenter, noninterventional, and transversal observational survey.
The mean age was 51.0±15.4 years, ranging from 6 to 96 years. The majority (61.4%) was female. The mean Ocular Surface Disease Index (OSDI) before the switch was surprisingly high at 56.0±23.5, and 73.0% of the patients had superficial punctate keratitis (SPK). The mean duration of use of preserved ATs before the switch was 15.8±12.1 months. OSDI scores and the presence of SPK correlated with the patients' ages but were independent of the duration of treatment with the preserved AT. The patients using ATs containing "soft" or "vanishing" preservatives presented exactly the same clinical pattern (level of OSDI and frequency of SPK) as those using ATs containing classical preservatives such as benzalkonium chloride (BAK). After switching to preservative-free AT containing hyaluronate (Hyabak®), the OSDI of 97.0% of the patients improved, decreasing from an average of 56.0 to an average of 28.2, with 23% of patients reporting a normal value of OSDI. The SPK frequency as well improved dramatically, with a frequency of positive fluorescein staining dropping from 73% to 46.1% of patients. A total of 94.0% of the patients considered that they preferred being treated with the preservative-free AT.
In patients suffering from DED and treated with a preserved AT, switching to a preservative-free AT provides clinical benefit by decreasing the severity of DED and reducing the prevalence of SPK, even after only 3 weeks of daily use of the preservative-free AT.