Clinical trial NCT02102880: The Role of Complement Factor H Polymorphism in the Regulation of Choroidal Vascular Tone in Young Healthy Subjects
Official title: The Role of Complement Factor H Polymorphism in the Regulation of Choroidal Vascular Tone in Young Healthy Subjects
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Age-Related Macular Degeneration
Keywords: Genetic Association Studies
Lead sponsor: Medical University of Vienna
Sponsor class: OTHER
First posted: 2014-04-03
Enrollment: 220
Sex: ALL
Minimum age (years): 18
Maximum age (years): 45
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: OTHER

Brief summary: Age related macular degeneration (AMD) is a multifactorial disease with a strong genetic component. Given that it is known that impaired regulation of choroidal vascular tone is present in patients with AMD, the current study seeks to investigate whether genetic polymorphisms in risk alleles for AMD are associated with altered choroidal blood flow regulation in healthy subjects. For this purpose a total of 220 healthy volunteers will be included. Choroidal blood flow regulation will be evaluated by measuring choroidal blood flow during isometric exercise. In addition, flicker induced vasodilatation will be studied and retinal vessel calibers will assessed, as well as retinal thickness and macular pigment optical density.


Eligibility criteria: Inclusion Criteria:

* Men and women aged between 18 and 45 years, nonsmokers
* Normal findings in the medical history and physical examination unless the investigator considers an abnormality to be clinically irrelevant
* Systolic blood pressure \< 160 mmHg, diastolic blood pressure \< 90 mmHg
* Normal ophthalmic findings, ametropia less than 3 diopters

Exclusion Criteria:

* Regular use of medication
* Abuse of alcoholic beverages
* Participation in a clinical trial in the 3 weeks preceding the study
* Treatment in the previous 3 weeks with any drug (except hormonal contraceptives)
* Symptoms of a clinically relevant illness in the 3 weeks before the first study day
* Blood donation during the previous 3 weeks
* History or family history of epilepsy
* Pregnancy, planned pregnancy or lactating

Primary outcomes:
measure: Choroidal blood flow during isometric exercise (LDF)
timeFrame: 1 day
Secondary outcomes:
measure: Flicker induced vasodilatation, expressed as percent change to baseline (DVA)
timeFrame: 1 day
measure: Genotyping (PCR)
timeFrame: 1 day
measure: Retinal vessel calibers and AV- ratio (DVA)
timeFrame: 1 day
measure: Laser Speckle Flowmetry (LSFG)
timeFrame: 1 day
Other outcomes:
Locations:
city: Vienna
country: Austria
facility: Department of Clinical Pharmacology, Medical University of Vienna
Study officials:
References:
citation: Calzetti G, Fondi K, Bata AM, Luft N, Wozniak PA, Witkowska KJ, Bolz M, Popa-Cherecheanu A, Werkmeister RM, Schmidl D, Garhofer G, Schmetterer L. Assessment of choroidal blood flow using laser speckle flowgraphy. Br J Ophthalmol. 2018 Dec;102(12):1679-1683. doi: 10.1136/bjophthalmol-2017-311750. Epub 2018 Feb 22.
citation: Witkowska KJ, Bata AM, Calzetti G, Luft N, Fondi K, Wozniak PA, Schmidl D, Bolz M, Popa-Cherecheanu A, Werkmeister RM, Garhofer G, Schmetterer L. Optic nerve head and retinal blood flow regulation during isometric exercise as assessed with laser speckle flowgraphy. PLoS One. 2017 Sep 12;12(9):e0184772. doi: 10.1371/journal.pone.0184772. eCollection 2017.