Abstract
Purpose: :
To report study design in a project examining dietary, environmental and genetic epidemiology of glaucoma.
Methods: :
The European Prospective Investigation of Cancer (EPIC) is a pan–European study of the role of dietary, lifestyle and genetic factors in cancer and other diseases of ageing. The EPIC Norfolk project enrolled 25,633 participants aged 45 to 74 years between 1993–97, with a first re–examination between 1997–2000. Particpants represent a broad spectrum of social and economic backgrounds, as well as urban versus rural living. Repeated examinations included height, weight, blood pressure, urinalysis and spirometry. Blood assays including full blood count, HbA1c and lipid profile, vitamin C, TSH and free T4. DNA has been stored. Seven day diet diaries have been completed twice. Questionnaires have been used to record physical activity (EPAQ2) and psycho–social status (HLEQ). A third healthcheck will commence January 2006 involving 10,000 participants, including assessment eyes and vision; specifically: LogMAR visual acuity, refractive error, axial dimensions, optic nerve head topography (HRT II), peripapillary retinal nerve fibre layer (GDx), digital disc and macular photography, intraocular pressure (ORA) on all subjects, with visual field testing (HFA2) on those with raised IOP or abnormal optic nerve anatomy. These methods have been assessed in a pilot study.
Results: :
To date, 275 people have participated in a pilot study of ocular examination. Of these there are 267 (97%) with IOP measures, 248 (90%) with GDx. The commonest reasons for incomplete GDx data were instrument failure and inability of subjects to align with fiaxtion target. Commenced after the start of the pilot study, a further 127 have undergone optic disc tomography by HRT II.
Conclusions: :
The main phase of this examination of community–based subjects will commence in January 2006, running for approximately 5 years.
Keywords: clinical (human) or epidemiologic studies: biostatistics/epidemiology methodology • clinical (human) or epidemiologic studies: risk factor assessment • clinical (human) or epidemiologic studies: natural history