title: Lower Vitamin D Level and Distinct Tear Cytokine Profile Were Observed in Patients with Mild Dry Eye Signs but Exaggerated Symptoms.
abstract: OBJECTIVE
  Dry eye is associated with inflammation, pain, and discomfort. Vitamin D is known to modulate immune responses and pain. This study investigates the level of serum vitamin D and tear-inflammatory proteins with relation to exaggerated symptoms in patients with mild dry eye.
  
  
  METHODS
  Patients with mild dry eye signs (Dry Eye Workshop [DEWS] severity grade 1) but with exaggerated symptoms and healthy controls (n= 19, each) were recruited for this cross-sectional study. Schirmer's Test I (mm), tear film break-up time (TBUT; secs), and ocular surface disease index (OSDI) score were recorded. Serum vitamin D level and tear cytokine levels were measured.
  
  
  RESULTS
  The mean OSDI score in the patient cohort (46 ± 3) was significantly higher than controls (8.4 ± 1.6). TBUT was lower (7.6 ± 0.3 secs) in patients compared with controls (11.0 ± 0.9 secs). Mean Schirmer's Test I value in patients (19.3 ± 1.4 mm) was lower than in controls (30.6 ± 1.9 mm). An inverse correlation was observed between serum vitamin D levels and OSDI score (r= -0.569;P= 0.01). Significantly higher levels of interleukin (IL)-17A/F, interferon (IFN)-γ, monocyte chemotactic protein (MCP)-1, intercellular adhesion molecule (ICAM)-1, IL-4, IL-10, and decreased IL-2 concentrations was observed in the tears of patients compared with controls (P< 0.05).
  
  
  CONCLUSIONS
  Decreased serum vitamin D was associated with exaggerated symptoms in dry eye patients with mild dry eye signs. In addition, altered tear cytokine profile was also observed in these patients.
  
  
  CONCLUSIONS
  Vitamin D measurements would aid in the diagnosis and management of dry eye.
authors.affiliation: Cornea and Refractive Surgery Division, Narayana Nethralaya Eye Hospital, Bangalore, India.
authors.forename: Rohit
authors.initials: R
authors.lastname: Shetty
authors.affiliation: GROW Research Laboratory, Narayana Nethralaya Foundation, Bangalore, India.
authors.forename: Swaminathan
authors.initials: S
authors.lastname: Sethu
authors.affiliation: GROW Research Laboratory, Narayana Nethralaya Foundation, Bangalore, India.
authors.forename: Priyanka
authors.initials: P
authors.lastname: Chevour
authors.affiliation: Cornea and Refractive Surgery Division, Narayana Nethralaya Eye Hospital, Bangalore, India.
authors.forename: Kalyani
authors.initials: K
authors.lastname: Deshpande
authors.affiliation: Cornea and Refractive Surgery Division, Narayana Nethralaya Eye Hospital, Bangalore, India.
authors.forename: Natasha
authors.initials: N
authors.lastname: Pahuja
authors.affiliation: Cornea and Refractive Surgery Division, Narayana Nethralaya Eye Hospital, Bangalore, India.
authors.forename: Harsha
authors.initials: H
authors.lastname: Nagaraja
authors.affiliation: Cornea and Refractive Surgery Division, Narayana Nethralaya Eye Hospital, Bangalore, India.
authors.forename: Narendra
authors.initials: N
authors.lastname: Pindipapanahalli
authors.affiliation: GROW Research Laboratory, Narayana Nethralaya Foundation, Bangalore, India.
authors.forename: Arkasubhra
authors.initials: A
authors.lastname: Ghosh
keywords: dry eye; inflammation; ocular surface; tears; vitamin D