The Role of Complement Factor H Polymorphism in the Regulation of Choroidal Vascular Tone in Young Healthy Subjects

The Role of Complement Factor H Polymorphism in the Regulation of Choroidal Vascular Tone in Young Healthy Subjects

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.

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