Detection of Acetylsalicylic Acid and Omega-3 Fatty Acids in Schirmers' Test Strips Using Mass Spectrometry

Study Overview
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Brief Summary
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Evaluation of tear fluid production using Schirmers' tests is a well-known and frequently used examination method in ophthalmology. Schirmers' test objectively indicates the tear fluid production over five minutes by insertion of a filter paper strip in the lower conjunctival fornix. Commonly, this method is used to quantify tear fluid production, but not tear fluid composition. The development of novel, very precise analytical methods opens up new possibilities in the use and application of Schirmers' test strips. A recently introduced analytical method is mass spectrometry. This method allows the detection and quantification of proteins, lipids, and metabolites in very low amounts of samples. Whether systemically ingested agents such as omega-3 fatty acids or acetylsalicylic acid can be detected in tear fluid using this method remains unclear. The aim of this study is to investigate the detectability of 2 different agents (acetylsalicylic acid and omega-3 fatty acids) in Schirmers' test strips from healthy subjects after intake for 1 week by use of untargeted mass spectrometry. Participating healthy subjects will receive either acetylsalicylic acid or omega-3 fatty acids.

Official Title
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Detection of Acetylsalicylic Acid and Omega-3 Fatty Acids in Schirmers' Test Strips Using Mass Spectrometry and Correlations With Tear Film and Blood Flow Parameters in Healthy Adults: an Open-label Pilot Study

Conditions
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Dry Eye

Intervention / Treatment
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* Drug: Aspirin 500Mg Tab
* Dietary Supplement: Dr. Böhm® Omega 3 complex 870 mg


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Men and women age of at least 18 years to 60 years Written informed consent prior to study-related procedures Normal ophthalmic findings No use of eye drops including topical lubricants in the 4 weeks before screening Exclusion Criteria: Participation in a clinical trial in the 3 weeks preceding the study Symptoms of a clinically relevant illness in the 3 weeks before the first study day Presence or history of a severe medical condition as judged by the clinical investigator Intake of any drugs or dietary supplements within three weeks before the first study day (except contraceptives) TFBUT <10 sec. Glaucoma in the medical history Ocular infection or clinically significant inflammation Ocular surgery in the 3 months preceding the study Pregnancy, planned pregnancy or lactating Known hypersensitivity to any component of the study medication

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Aspirin® 500 mg tablets<br>Dose: 1 tablet per day starting from visit 2 until visit 3, intake in the evening Ingredients: 500 mg acetylsalicylic acid, Cellulose powder, maize starche | Drug: Aspirin 500Mg Tab<br>* Dose: 1 tablet per day starting from visit 2 until visit 3, intake in the evening<br>|
| Experimental: Dr. Böhm® Omega 3 complex 870 mg<br>Dose: 2 tablets per day starting from visit 2 until visit 3, intake in the evening | Dietary Supplement: Dr. Böhm® Omega 3 complex 870 mg<br>* Dose: 2 tablets per day starting from visit 2 until visit 3, intake in the evening<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Concentration of omega-3 fatty acids/ASS detectable in Schirmer's tear strips using mass spectrometry |  | one week | 
| Change of nAUC (normalised area under the curve) of tear fluid metabolics from baseline to follow-up visit using mass spectrometry |  | one week | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| To evaluate the influence of omega-3 FA/ASS on lipid layer thickness | Lipid layer thickness will be measured by LipiView and expressed as nanometers | one week | 
| To evaluate the influence of omega-3 FA/ASS on corneal sensation | Corneal sensation as measured by a Cochet-Bonnet aesthesiometer will be expressed as milimeters | one week | 
| To evaluate the influence of omega-3 FA/ASS on tear film break up time | Tear film break up time will be measured clinically and expressed as seconds | one week | 
| To evaluate the influence of omega-3 FA/ASS on Schirmer-1 test | Schirmer-1 test will be expressed as milimetres/5 minutes | one week | 
| To evaluate the influence of omega-3 FA/ASS on choroidal perfusion | choroidal perfusion will be measured using a LSFG device and expressed as mean blur rate | one week | 
| To evaluate the influence of omega-3 FA/ASS on central macular thickness | central macular thickness will be measured by OCT and expressed as µm | one week | 
| To evaluate the influence of omega-3 FA/ASS on vessel density as assessed by optical coherence tomography angiography | vessel density will be measured by OCTA | one week | 
| To evaluate the influence of omega-3 FA/ASS on tear film osmolarity | tear film osmolarity will be measured by TearLab and expressed as mOsm/L | one week | 
| Concentration of omega-3 fatty acids/ASS detectable in finger sweat samples and blood samples using mass spectrometry |  | one week |